BU-304a: Safety Concerns with Li-ion

Learn what causes Li-ion to fail and what to do in case of fire.

Safety of lithium-based batteries has attracted much media and legal attention. Any energy storage device carries a risk, as demonstrated in the 1800s when steam engines exploded and people got hurt. Carrying highly flammable gasoline in cars was a hot topic in the early 1900s. All batteries carry a safety risk, and battery makers are obligated to meet safety requirements; less reputable firms are knowns to make shortcuts and it’s “buyer beware!”

Lithium-ion is safe but with millions of consumers using batteries, failures are bound to happen. In 2006, a one-in-200,000 breakdown triggered a recall of almost six million lithium-ion packs. Sony, the maker of the lithium-ion cells in question, points out that on rare occasion microscopic metal particles may come into contact with other parts of the battery cell, leading to a short circuit within the cell.

Battery manufacturers strive to minimize the presence of metallic particles. The semiconductor industry has spent billions of dollars to find ways in reducing particles that reduce the yield in wafers. Advanced cleanrooms are Class 10 in which 10,000 particles larger than 0.1µm per cubic meter are present (ISO 4 under ISO 14644 and ISO 14698). In spite of this high cleanliness, particle defects still occur in semiconductor wafers. Class 10 reduces the particles count but does not fully eliminate them.

Battery manufacturers may use less stringently controlled cleanrooms than the semiconductor industry. While a non-functioning semiconductor simply ends up in the garbage bin, a compromised Li-ion can make its way into the workforce undetected and deteriorate without knowing. Resulting failures are especially critical with the thinning of the separators to increase the specific energy.

Cells with ultra-thin separators of 24µm or less (24-thousandth of an mm) are more susceptible to impurities than the older designs with lower Ah ratings. Whereas the 1,350mAh cell in the 18650 package could tolerate a nail penetration test, the high-density 3,400mAh can ignite when performing the same test. (See BU-306: What is the Function of the Separator?) New safety standards direct how batteries are used, and the UL1642 Underwriters Laboratories (UL) test no longer mandates nail penetration for safety acceptance of lithium-based batteries.

Li-ion using conventional metal oxides is nearing its theoretical limit on specific energy. Rather than optimizing capacity, battery makers are improving manufacturing methods to enhance safety and increase calendar life. The real problem lies when on rare occasions an electrical short develops inside the cell. The external protection peripherals are ineffective to stop a thermal runaway once in progress. The batteries recalled in 2006 had passed the UL safety requirements — yet they failed under normal use with appropriate protection circuits.

There are two basic types of battery failures. One occurs at a predictable interval-per-million and is connected with a design flaw involving the electrode, separator, electrolyte or processes. These defects often involve a recall to correct a discovered flaw. The more difficult failures are random events that do not point to a design flaw. It may be a stress event like charging at sub-freezing temperature, vibration, or a fluke incident that is comparable to being hit by a meteor.  

Let’s examine the inner workings of the cell more closely. A mild short will only cause elevated self-discharge and the heat buildup is minimal because the discharging power is very low. If enough microscopic metallic particles converge on one spot, a sizable current begins to flow between the electrodes of the cell, and the spot heats up and weakens. As a small water leak in a faulty hydro dam can develop into a torrent and take a structure down, so too can heat buildup damage the insulation layer in a cell and cause an electrical short. The temperature can quickly reach 500C (932F), at which point the cell catches fire or it explodes. This thermal runaway that occurs is known as “venting with flame.” “Rapid disassembly” is the preferred term by the battery industry.

Uneven separators can also trigger cell failure. Poor conductivity due to dry areas increases the resistance, which can generate local heat spots that weaken the integrity of the separator. Heat is always an enemy of the battery.

Most major Li-ion cell manufacturer x-ray every single cell as part of automated quality control. Software examines anomalies such as bent tabs or crushed jelly rolls. This is the reason why Li-ion batteries are so safe today, but such careful manufacturing practices may only be offered with recognized brands.

Why Batteries Fail

Quality lithium-ion batteries are safe if used as intended. However, a high number of heat and fire failures had been reported in consumer products that use non-certified batteries, and the hoverboard is an example. This may have been solved with the use of certified Li-ion on most current models. A UL official at a meeting in the Washington, D.C. area said that no new incident of overheating or fire had been reported since Li-ion in hoverboards was certified. Fires originating in the Samsung Galaxy Note 7 were due to a manufacturing defect that had been solved. The main-ship battery in the Boeing 787 Dreamliner also had defects that were resolved.

Incorrect uses of all batteries are excessive vibration, elevated heat and charging Li-ion below freezing. (See BU-410: Charging at High and Low Temperature.) Li-ion and lead acid batteries cannot be fully discharged and must be stored with a remaining charge. While nickel-based batteries can be stored in a fully discharged state with no apparent side effect, Li-ion must not dip below 2V/cell for any length of time. Copper shunts form inside the cells that can lead to elevated self-discharge or a partial electrical short. If recharged, the cells might become unstable, causing excessive heat or showing other anomalies.

Heat combined with a full charge is said to induce more stress to Li-ion than regular cycling. Keep the battery and a device away from sun exposure and store in a cool place at a partial charge. Exceeding the recommended charge current by ultra-fast changing also harms Li-ion. Nickel-cadmium is the only chemistry that accepts ultra-fast charging with minimal stress. (See BU-401a: Fast and Ultra-fast Chargers.)

Li-ion batteries that have been exposed to stresses may function normally but they become more sensitive to mechanical abuse. The liability for a failed battery goes to the manufacturer even if the fault may have been caused by improper use and handling. This worries the battery manufacturers and they go the extra mile to make their products safe. Treat the battery as if it were a living organism by preventing excess stress. 

With more than a billion mobile phones and computers used in the world every day, the number of accidents is small. By comparison, the National Oceanic and Atmospheric Administration say that your chance of being struck by lightning in the course of a lifetime is about 1 in 13,000. Lithium-ion batteries have a failure rate that is less than one in a million. The failure rate of a quality Li-ion cell is better than 1 in 10 million.

Industrial batteries, such as those used for power tools, are generally more rugged than those in consumer products. Besides solid construction, power tool batteries are maximized for power delivery and less on energy for long runtimes. Power Cells have a lower Ah rating than Energy Cells and are in general more tolerant and safer if abused.

Battery Safety in Public addresses concerns with consumer batteries. One of the most accident-prone batteries is Li-ion in an 18650 cell with an unfamiliar brand name. These batteries made available for vaping do not have the same quality and safety as a recognized brand name. Li-ion is safe if made by a reputable manufacturer, but there have been a number fires and injuries with cells that developed defects and caught fire while carrying in clothing and while traveling. An onboard fire forced a WestJet plane to return to the airport in 2018 soon after takeoff. The burning e-cigarette battery was illegally placed in baggage as spare and checked in. The plane’s cargo bay is not accessible when in flight and a burning battery requires an unscheduled landing. The U.S. Federal Aviation Administration recorded 206 incidents involving Li-ion batteries between 1991 and 2018.

What to Do When a Battery Overheats or Catches Fire

If a Li-ion battery overheats, hisses or bulges, immediately move the device away from flammable materials and place it on a non-combustible surface. If at all possible, remove the battery and put it outdoors to burn out. Simply disconnecting the battery from charge may not stop its destructive path.

A small Li-ion fire can be handled like any other combustible fire. For best result use a foam extinguisher, CO2, ABC dry chemical, powdered graphite, copper powder or soda (sodium carbonate). If the fire occurs in an airplane cabin, the FAA instructs flight attendants to use water or soda pop. Water-based products are most readily available and are appropriate since Li-ion contains very little lithium metal that reacts with water. Water also cools the adjacent area and prevents the fire from spreading. Research laboratories and factories also use water to extinguish Li-ion battery fires.

Crew can’t access the cargo areas of a passenger aircraft during flight. To assure safety in case of a fire, planes rely on fire suppression systems. Halon is a common fire suppressant, but this agent may not be sufficient to extinguish a Li-ion fire in the cargo bay. FAA tests found that the anti-fire halon gas installed in airline cargo areas can’t extinguish a battery fire that combines with other highly flammable material, such as the gas in an aerosol can or cosmetics commonly carried by travelers. However, the system prevents the blaze from spreading to adjacent flammable material such as cardboard or clothing.

A large Li-ion fire, such as in an EV, may need to burn out. Water with copper material can be used, but this may not be available and is costly for fire halls. Increasingly, experts advise using water even with large Li-ion fires. Water lowers combustion temperature but is not recommended for battery fires containing lithium-metal.

When encountering a fire with a lithium-metal battery, only use a Class D fire extinguisher. Lithium-metal contains plenty of lithium that reacts with water and makes the fire worse. As the number of EVs grows, so must the methods to extinguish such fires.

CAUTION Do not use a Class D fire extinguisher to put out other types of fires; make certain regular extinguishers are also available. With all battery fires, allow ample ventilation while the battery burns itself out.

During a thermal runaway, the high heat of the failing cell inside a battery pack may propagate to the next cells, causing them to become thermally unstable also. A chain reaction can occur in which each cell disintegrates on its own timetable. A pack can thus be destroyed in a few seconds or over several hours as each cell is being consumed. To increase safety, packs should include dividers to protect the failing cell from spreading to the neighboring one. Figure 1 shows a laptop that was damaged by a faulty Li-ion battery.

Suspected Li-ion battery destroys laptop

Figure 1: Li-ion battery suspected to have destroyed the laptop.
The owner says the laptop popped, hissed, sizzled and began filling the room with smoke.

Source: Shmuel De-Leon

The gas released by a venting Li-ion cell is mainly carbon dioxide (CO2). Other gases that form through heating are vaporized electrolyte consisting of hydrogen fluoride (HF) from 20–200mg/Wh, and phosphoryl fluoride (POF3) from 15–22mg/Wh. Burning gases also include combustion products and organic solvents.

The knowledge on the toxicity of burning electrolyte is limited and toxicity can be higher than with regular combustibles. Ventilate the room and vacate area if smoke and gases are present. Gas and smoke in a confined area such as an aircraft, submarine and mine shaft will present a potential health risk.

While lithium-based batteries are heavily studied for safety, nickel- and lead-based batteries also cause fires and are being recalled. The reasons are faulty separators resulting from aging, rough handling, excessive vibration and high-temperature. Lithium-ion batteries have become very safe and heat-related failures occur rarely when used correctly.


Hydrogen fluoride (HF) is a colorless gas or liquid substance. It is the principal source of fluorine, a feedstock for pharmaceuticals, polymers (Teflon) and assisting petrochemical industries. Hydrogen fluoride is a highly dangerous gas, forming corrosive and penetrating hydrofluoric acid with moisture. In large quantities, gas can cause blindness by destruction of the corneas.

Phosphoryl fluoride (POF3) is a colorless gas that hydrolyzes rapidly.

Lithium hexafluorophosphate (LiPF6) is an inorganic compound in the form of white crystalline powder serving as electrolyte in Li-ion batteries.


Simple Guidelines for Using Lithium-ion Batteries

Last Updated 2019-01-23

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Comments (126)

On November 3, 2011 at 4:50am
JasonsRobot  wrote:

Lithium0ion batteries are safest just because their manufacturing process and techniques are truly based of professional use. Its hardly you hear of any heat failure of it. batteries promise long life time come with high percentage of energy failure.

On January 16, 2013 at 2:58am
antoinecoca wrote:

Would anyone know which certifications and norms the Li-Ion battery must comply with when imported in Europe?

On October 28, 2013 at 4:04am
Maria wrote:


I would like to know if someone has data about how hot could a Lithium ion battery culd actually burn? (for large scale fires).

Tks in advanced.

On May 28, 2014 at 10:10am
Louis wrote:

Can I charge Li-ION 4500mAh 3.7V Battery with my “regular” Ni-Cd / Ni-MH RadioShack charger, if so what setting works the best, if any.


On July 19, 2014 at 8:07pm
Brendon wrote:

@Louis:  Definitely not!  Li-Ion is a very different chemistry from NiCd ard NiMH.  Each chemistry requires the use of a charger specifically designed for it.

On July 31, 2014 at 4:43am
j wrote:

We have a lithium fire extinguisher at work… how does it do it? DHL will send batteries by air somehow… there needs to be a way to send batteries safely…

On September 22, 2014 at 8:29pm
BB wrote:

someone played a joke on me by putting a lithium ion battery for a power tool in my oven.  I didn’t know and preheated my oven to 450 degrees before I smelled the plastic melting and discovered it.  How dangerous was this?  Could it have exploded and injured me??

On November 4, 2014 at 8:07am
Dan wrote:

@BB: You should immediately cease contact with that individual and surround yourself with more intelligent beings.

On December 2, 2014 at 2:12pm
Pillow wrote:

I recently got myself Gameboy advance SP and it has Lithium Ion battery. Since it did not come with charger, my dad tried to charge it with home-made charger, he crafted it using old nokia phone charger. Soon, when I was alone home, I discovered that the battery was a bit bigger than before and it was pretty hot. I unplugged it inmediatly and my dad said that he will see if he can charge it on safer way. I would like to ask, should I get the new battery? Is using the same battery dangerous even if it goes back to its normal size? What should I do?

On December 31, 2014 at 9:21am
sp00zer wrote:

Get a new battery right away. Changing physical size is an indication of internal chemical change in the direction of failure. A battery like that should never be reused inside of a device.

On February 18, 2015 at 12:48am
Thomas wrote:

I’m constantly bing told that water is the way to extinguish Li ion fires. And yet fire suppression companies sell class D extinguishers and say that water is NOT the way to fight these fires. What are the facts?

On February 26, 2015 at 10:36pm
Richard A. wrote:

I work for a company that exchanges fire extinguishers in buildings. There is a battery test lab for an automaker that I am iffy about the right extinguishers. They want an ABC, but wouldn’t a Dry Chem Sodium BiCarb be better due to the corrosive factors?

On March 23, 2015 at 3:33pm
Rich wrote:

For primary cells with Lithium, absolutely do no use water. The lithium will react with the water and you will have even more of an issue on your hands. So 1 use coin cells and the like, Class D extinguisher.

For Secondary cells, especially ones that are part of a pack.Put out the flame with pretty much any of the listed extinguishers above then you want to use water and a lot of it. The amount of lithium in secondary Li-Poly and Li-Ion cells is quite low and won’t react. Your goal with the water is want to drop the temp of the surrounding batteries so they don’t overheat and vent.

On May 2, 2015 at 1:38am
khan wrote:

my child put samsung phone battery 3.7 v in warm cup of tea that i drank. After realizing it, i hurried and took it out. Some white solid was already there at electrodes. Now i worry for health concern specially bcza i m 6 months pregnant. I m drinking lot of water and vomited as well. What kind of chemical would have released in so short time and what else can i do now.

On May 16, 2015 at 2:37am
roland wrote:

i`m no doctor and also no chemist, but i wouldnt worry.  the white solid is probably some electrolytic result of the current flow through the tea/liquid, as it can transport electrons. i`m sure, that no inner (or even poisonous) materials from the battery have leaked into the tea and your health is not at danger

On May 21, 2015 at 1:21pm
David wrote:

“If the fire occurs in an airplane, the FAA instructs flight attendants not to use fire extinguishers but the use of water or pop soda. Water cools the adjacent material and prevents the fire from spreading. Many research laboratories and factories also use water to put out battery fires… Li-ion contains no lithium metal and does not react with water (lithium metal batteries requires different extinguishing methods).”

Ok, so I’ve learned to use water, not fire extinguishers, and Li-ion batteries don’t react with water.

Then it says:

“Use a foam extinguisher, CO2, dry chemical, powdered graphite, copper powder or soda (sodium carbonate) to extinguish a lithium-ion fire. Only pour water to prevent the fire from spreading as water interacts with lithium.”

Ok, so now I’ve learned the precise opposite - to use fire extinguishers, not water, and Li-ion batteries DO react with water.

Very confusing.

On May 22, 2015 at 11:43am
Cadex Electronics Inc. wrote:

Thanks David, We have updated the article to clarify.

On June 5, 2015 at 7:28am
Terri wrote:

Has anyone heard of any Samsung SDI Li-Ion batteries used in HP Compaq recalls?

On June 25, 2015 at 5:07pm
Rod East wrote:

I am a serving professional Senior Fire Investigator and would like further infomation regarding the failures and way to identify the failure within the Lith-ion batteries.

On July 3, 2015 at 6:22am
raj wrote:

i have a blackberry MS 1 battery that has bulged and cracked.

Is it toxic to me or anyone around me to handle?
Are there any fumes that may be released?

Should I continue using it? It works fine, although the charge runs out quickly

On July 16, 2015 at 6:52am
Sue wrote:

Do lithium batteries leak out?  They seem so toxic I am concerned about having them in the clock radio that sits right next to my head all night!

On July 28, 2015 at 8:39pm
Erika wrote:

Can I use a lithium motorcycle battery in a fiberglass toolbox under the seat? Or is this a big no-no? Thanks.

On August 20, 2015 at 12:58pm
gary monroe wrote:

Does anyone know of a Lithium Ion Battery Handling Safety presentation (ppt) or onsite instructor-led course?  My company deals with Li-ion batteries in a big way and need a good battery handling course.

On September 12, 2015 at 8:50pm
Malia Skinner wrote:

i come down starts to find my tablet destroyed i threw it away cause it wasent working anymore and my tablets battery came out and my brother opens the battery and thosed it in the trash and came to get it i wasent expecting until my brother was holding it all of a sudden it got hot and the next thing the long battery ligt on fire what was the cause of this was it because my brother destoryed ot or long enough exposure to oxygen? please help me answer

On September 18, 2015 at 1:00am
n.z wrote:

what’s the range of moisture that li-ion battery can be safe when we want to open it?

On October 21, 2015 at 1:53pm
Robert Dubé wrote:

@gary monroe
I came across this while looking for battery info http://excellbattery.com/wp-content/uploads/2015/02/Safety-Presentation-FEB-2015.pdf
This company also have some training available, look in the top menu for training http://excellbattery.com I am not relate to the company and do not know about the paid trainings.

On November 26, 2015 at 4:31pm
Robert Irvine wrote:

Can a cell phone explode in a steam room at the gym some people are using them more frequently I think it may cause burns or worse please help

On December 4, 2015 at 2:11am
Tonawr wrote:

QUESTION. IF YOU’RE CHARGUNG YOUR LITHIUM BATTERY AND OVER 4.300 (the point of pressure buildup). will the pressure go away after taking it off the charger, or will that pressure stay there, making it able to explode anytime I begin charging it?

On December 11, 2015 at 3:32pm
Roger Bohn wrote:

Raj: Swollen, cracked, broken, or holed lithium batteries: treat them as dangerous! DO NOT USE; DO NOT RECHARGE. Even if they don’t burn your house down (happened to a friend of mine) they cause an unholy smell when they burn, which is very hard to get rid of.

Tonawr: Not sure what pressure you are referring to. Are you talking about the Amp-hour (charge) level? In that case, if you continue to charge past its rating it will eventually catch fire, but not because of physical pressure. Good batteries, and good chargers, are carefully designed to prevent overcharging.

On December 16, 2015 at 2:46pm
Craig Blair wrote:

Is there any way to be forewarned of a Lithium- ion battery’s eminent failure? Is temperature an effective way to predict it, or is it ONLY a matter of metal particles causing a short? IF temperature provides an effective warning, at what temp should one cease operation?

On January 2, 2016 at 9:00am
Deb Freed wrote:

my son has a hoverboard and I know there have been issues with them beating into flames.  How can I safely store the hoverboard so that a fire would be contained if it combusts while no one is home?  Would it be safest in the bathtub? Wrapped in a fire safety blanket? Placed in a fire safe (seems like an expensive solution)? Or do I just spend my life in a panic that my house will burn down when I’m not home?

On January 2, 2016 at 12:09pm
Roger Bohn wrote:

1. Most important, only charge it when someone is home and in the same room. Most fires occur when charging. If possible, charge outdoors. Also for some period after charging.

2. Store: on a concrete floor with nothing around (garage). Bathtub is ok but not very practical. Fire blanket is good.

3. When in any crash (which is probably common) - treat it as likely to go off for the next few hours. If the battery OR circuitry were damaged, such as a short circuit, a fire is more likely.  Good luck!

On January 2, 2016 at 2:28pm
Deb Freed wrote:

My brother suggests draining the battery (running the hoverboard until the battery is dead) and then storing it that way.  Would that eliminate the risk of spontaneous combusyion?  If so, that is a simple solution.  My son can just charge the hoverboard the next time he wants to use it (he will be away for several weeks).

On January 2, 2016 at 2:48pm
Roger Bohn wrote:

Yes it will reduce risk of combustion, but no, you do not want to do that. Draining a lithium ion battery reduces its life considerably. In extreme cases, you can ruin the battery.

He does have a very good point thought that you should store it at an intermediate charge level. Do not store fully charged, because that somewhat increases the risks as well as increasing the size of a fire if one occurs.

By the way, is there a better discussion board for discussing these boards specifically?

On January 4, 2016 at 12:06am
Dave Potter wrote:

The hoverboards and laptops are getting a lot of attention, what about the 18650 batteries used in flashlights and other small devices?

On January 4, 2016 at 12:15am
Roger Bohn wrote:

Good question. I have not heard of problems with 18650s, but on the other hand I refuse to buy the cheap ones because I expect that they have the same sorts of safety hazards.

I know there are some reputable companies - I think Panasonic is the main one. Panasonic makes the energy storage core; other companies then add the electronics. So a Panasonic core + cheap electronics is sti≥ll dangerous.

Maybe someone can research and provide URls .

On January 4, 2016 at 12:20am
Roger Bohn wrote:

I have written a short blog post on hoverboard battery safety. Visit Art2science.org
Comments and questions there are welcome

On January 4, 2016 at 10:03am
Ron Butler wrote:

As the “building block cell”,18650’s certainly possess a failure potential. Most of the available burn tests have been done using these cells.

On January 12, 2016 at 3:48am
Andy Lea wrote:

I have 4 cells in a waterproof case. Do I need to remove the cells to charge? The box is probably air tight. Do the cells need to vent gas?

On January 18, 2016 at 4:43am
paul dennison wrote:

On Saturday evening a 3000mA/h brand name Efest exploded in my e-cig in my hand. The room filled with thick smoke and several small fires were caused as the device took off like a rocket I was able deal with these.Clearly I breathed the smoke in, but the room and I were covered with black dust.  Is there any medical advise on what I should do now please?
Is there any legal advise?


On January 18, 2016 at 2:30pm
Roger Bohn wrote:

Smoke inhalation is potentially serious, but seek real advice. I got a small whiff once, and it aggravated my asthma for a day.

Can you say more about circumstances? Were you using it at the time? Charging it?

I also wonder why such a large battery was in the product. But I know nothing about e-cigs. 
Thanks for reporting this - I hope you will post this incident more widely e.g. on e-cig sites.

On January 19, 2016 at 12:52am
Bob Seaver wrote:

I have a cell stuck in my Nikon D5000.  If I sdrill a hole in it to gewt it out, is that dangerous?

On January 19, 2016 at 1:06am
Bob Seaver wrote:

The cell is identified by a label that says it is a li-ion cell.  It is tha standad battery thati is used ro power Nikon D5000s but not a Nikon product; so it resisted being inserted and is struck by friction in the camera body.  Sorry to be so vague, but this is new for me.

On January 19, 2016 at 2:55am
paul dennison wrote:

The e-cig WAS a “Nemesis” made of stainless steel approx 106 mm by 22 mm dia.
I was changing the discharged battery with one from charger designed for these batteries.
It exploded as I hand tightened the parts together. Later that day I experienced severe stomach pains,and on advice from NHS direct then from my GP I visited A&E.  I was given two blood tests My only symptoms were stomach pain and small burn on my leg.They found a minor infection in my kidneys and provided antibiotics for this, conclusion the pain and e-cig were unrelated. I took photos of the carnage which a can email if required,please provide an emaill address. Thanks

On January 19, 2016 at 9:42am
RB wrote:

Don’t do it!  Sticking metal into a charged battery is guaranteed to short circuit and cause a fire. 99%. At best it would destroy the camera. At worst, burn your hands and start a bigger fire.
  How about finding a site of Nikon camera people and asking them?

On January 19, 2016 at 11:47am
Roger Bohn wrote:

To Bob: To strengthen my message: NO!!!!! It’s really going to make a mess and perhaps start a fire. And destroy the camera. And burn your hands if you don’t drop it fast enough.
If for some reason you decide to do it anyway, please do it outside and not near any flammable material.

Physical damage to a lithium battery is the second big cause of fires (along with overcharging). In radio controlled flying, when a plane does a nose-dive, we treat the battery as “about to catch fire.”
  Good luck. I bet there is another way to get that battery out.

On January 23, 2016 at 7:34am
barbara cissell wrote:

Do you recommend charging a laptop ion battery to only 90% to prevent overcharging and exploding.I have heard this is a good number.Also,how low should I let it get down to before I plug it back in? Is 2% a good number? Thank you.Confused in Louisville Ky

On January 25, 2016 at 1:38am
Roger Bohn wrote:

Barbara, don’t worry about laptop batteries, assuming the laptop is made by a first or second tier brand name. They are MUCH safer, with electronics to protect against overcharging, over-discharging, etc.
Laptop batteries cannot be overcharged because of protection in both the battery and the charger. You will slightly reduce the life if you let them be fully discharged frequently, but they are intended to give a full charge from 100 down to 0.

Why the safety difference? Brand name: Cases of laptop fires get lots of attention. Also certification by UL laboratories. Also government regulation: the CPSC would get involved if there were persistent problems. Also tort law: fires would lead to lawsuits.

Fires of the hoverboards will lead to lawsuits, but I expect that the companies that made them will be hard to locate, and then will turn out to have no assets if someone wins a suit. Tort lawyers have a bad reputation, but this is an example of why they can be good for safety!

On February 8, 2016 at 4:06pm
Verena Jolly wrote:

Hi, I’ve bought a GPS tracker with a Li-ion battery that I wanted to use on my horse.  Having read the info here…it sounds like there’s a risk of it setting on fire/exploding and injuring/killing her, especially as it could be subjected to some forces if she were to squash it when lying down to sleep etc.  Can anyone confirm please if I’ve correctly understood the risks?  GPS trackers are commonly used on pets and they presumably have lithium ion batteries…so are they risky too?

On February 12, 2016 at 1:43am
subrata das wrote:

Drones, mobile phones, laptops, mobile appliances use LITHIUM batteries. Avoid using chargers that implement fast charging overnight. Avoid power extension sockets near sofa, living room carpet. CHARGERS should be kept in well-ventilated area.
Mr Ian Johnson, 74 technical expert, attended a course in Germany on operating drones, left three drone LITHIUM polymer batteries to charge on the carpet floor besides sofa. At 3am in just 2 hours 4-generation family house reduced to a charred state at Parry Avenue Singapore, June 9, 2015. He died of extensive burns in the corridor.

On February 21, 2016 at 8:41am
philico wrote:

The risk of lithium ion batteries catching fire occurs when the battery has current flowing into it, that is, when charging or when in use. When the Li-ion batteries are not in use, they should be as safe as a tomato in your fridge, right?

I would like an answer to this question: Being out of any device it powers and being non-operated upon, i.e. there is no current load running through it, has anyone ever witnessed a Li-ion battery spontaneously catching fire?

On February 21, 2016 at 10:16am
Roger wrote:

Philico it’s a good question. Sounds logical, but it’s wrong.  Most fires occur while charging, some when in use, but there are documented seemingly spontaneous fires. Typically after an accident that physically damaged the battery internally. But an air freighter was destroyed by fire in batteries that were being shipped and were not in use at the time, not even plugged into anything.

On February 21, 2016 at 10:20am
Roger wrote:

Philico, this is a case where quality matters. A well made battery won’t do this. But there are some unqualified manufacturers in China whose batteries can have micro defects that eventually cause a short circuit.

On February 22, 2016 at 11:04am
philico wrote:

Roger, your answer makes sense. Batteries even without any current load seem to leak charge, even though this residual leak is normally pretty small. Can it be the case where mechanical vibrations like those involved during transportation can help dissipate charge inside the battery? Or, maybe humid conditions can help create a path for current to flow internally? whatever it is, I wasn’t aware that even under such small perturbations Lipos can spontaneously ignite.

So far I’ve owned and operated hundreds of Li-ion batteries and in only 2 cases I witnessed slight bulging in two incidents, although this bulging was very gradual and over the span of months.

On February 22, 2016 at 11:15am
Roger Bohn wrote:

Hundreds of batteries with virtually no problem — I would guess you are using good brands? Why so many, if I may ask? Also, perhaps you discard batteries when they lose effectiveness?

Residual leakage - yes, good point. Fires in that situation are presumably due to thermal runaway of some kind.

Keep up the good results. Lipo fires ARE rare, but they can be so disastrous when they happen that it makes sense to be very careful.

On February 22, 2016 at 1:35pm
philico wrote:

Roger - Not really. I almost always buy non-brand LIPO batteries, mainly because they are cheap. This is across the board, even those meant to replace those in my notebooks, smartphones and tablets. Why so many? Because I’m a gadget junkie and also because as you mentioned, I like to keep my devices running by recycling their batteries. I’m also an electronics / ham radio enthusiast and some of these batteries power up many of my projects.

There are billions of LIPO batteries currently in service and I’m safely estimating x20 more retired or not in service. The chance of a battery catching fire is extremely low. If it wasn’t, airline companies would have banned carrying electronic devices on board by now. Who knows. It only takes one bad incident to cause such a ban but let’s hope we’ll never get there. The race is on to make LI-ion technology fire safe.

On February 23, 2016 at 5:41pm
Ron Butler wrote:

Philico Roger is correct. The state of charge has a bearing on the potential for thermal runaway. However, failures can occur even if the SOC is approaching 0%

On February 23, 2016 at 10:58pm
philico wrote:

Ron - Can you please translate things into simple English so that our non-technical fellow readers can understand?

On February 23, 2016 at 11:36pm
philico wrote:

I’m not trying to refute the validity of this article or the fact that Lithium ion polymer batteries can’t catch fire. However, quoting you statement “In 2006, a one-in-200,000 breakdown…”, it tells me that the likelihood of your smartphone being struck by a lightning is probably higher than catching fire from the battery it carries! Of course, if you are so eager to prove me wrong by going as far as driving a nail though it then by all means you should be my guest and do it.

On February 24, 2016 at 10:59am
Roger Bohn wrote:

Philico, I think we agree. Just to be clear I make a distinction between:
Name-brand cellphone and notebook batteries. They are very reliable.

Bare, off-brand Lipos such as used for hoverboards and hobbyist use. They are NOT very reliable.

Partly it’s the batteries themselves; partly it’s the circuitry that monitors them when charging and discharging. So excellent safety of cellphones does not tell us much about hoverboards. For someone not familiar with them, buy only name brand equipment.

On February 24, 2016 at 12:25pm
philico wrote:

Roger - If you look at the capacity of cellphone and notebook batteries, you will notice a conservative behavior by manufacturers of using lower mAh values which makes me suspect that the polymer used is less densely packed and that probably makes things inherently safer. After all, its not the end of the world if you have few hours less until you plug that power cable back to the device. In addition, smart devices usually employ sophisticated software to conserve power. However, with equipment that require a lot of power such as power tools, hoverboards or drones, having a less powerful battery or trying to conserve power is not an option. So the risk of fire is presumably higher.

Another issue to be noted is that in their effort to compete with brand names, manufacturers of non-brand batteries often increase the capacity of a specific model by offering higher mAh values for a lesser price than the brand equivalent. People often fall for this. The issues I expect to see are higher failures and/or lower lifetimes although I have no evidence to back my claim. Can anyone help clarify?

On March 17, 2016 at 6:22am
Ted wrote:

Hi, we had a very sceary situation when my friend and i was replacing a iphone 6 battery. the battery is glued in the back cover and we had to bend it to get it of. Suddenly the battery sonded like a rocket engine and cought fire, the whole phone was destroyd.
My question is, would emptying the battery before replacing it had prevent this?

On March 17, 2016 at 11:01am
Roger Bohn wrote:

Ted, thanks for posting this. What you did will almost always cause a fire, because bending the battery breaks it inside, causing a short circuit.

Emptying the battery first would have reduced the size of the fire but the phone probably would still have been destroyed.

Whoever sold you a replacement battery, without warning about the hazards, should refund your money. Since it is an iPhone 6,  it should still have been under 1 year warranty anyway.
The best way to deal with a dying battery these days is to get an external plug-in battery. Don’t touch what is inside the case.

On March 18, 2016 at 10:31am
philico wrote:

Ted - I always fully drain the battery before I replace it from the device and I’ve done that many times so far without any fire hazard issues. I also ground myself while working on the device and battery. An empty battery has no active charge in it and if no charges get transferred or mechanically generated while removing it, it should be safe to handle. When you handle exposed electronics it is a good practice to ground yourself to avoid any static charges transferring that may damage the circuit. In a similar fashion, you may want to ground yourself when handling LIPO batteries especially those that are not shielded by a metal case to avoid any static charge buildup that would cause it to catch fire.

On March 18, 2016 at 12:16pm
Roger Bohn wrote:

Hi philico, you are more experienced than I and also more optimistic. I assume you are talking about batteries that are designed to be removed and replaced. That does not cover iPhones, nor most modern notebook computers, which have “integral batteries.” I considered replacing the battery on my Macbook Pro, for example, but it costs $700 because the keyboard and other circuitry has to be replaced at the same time.

Regarding zero charge state: ?? For the batteries I work with, they never reach zero charge, because if you let them get to that level it ruins the chemistry. I believe that similarly the charge/discharge electronics in a phone shut down the power before it reaches physical zero on the battery. I know my hybrid car battery works that way. Even at “zero” it can still start a fire.

On March 18, 2016 at 11:43pm
philico wrote:

Hi Roger - I don’t understand your point. Why do you worry about ruining the chemistry of a battery that is to be replaced? Personally I don’t since the batteries I replace are, well, dead or almost dead and if they are not, I make sure they get there… Sorry, I’m not a fan of Mac devices for the reason you indicated in your answer. As far as your claim that “even at a “zero” it can still catch fire”, well, do you have any substantiated proof?

On April 23, 2016 at 3:03pm
Alec Heesacker wrote:

We personally need non explodable batteries in laptops, psp, 3DS and phones.
I don’t want to have to spend thousands of dollars to repair or replace my electronics, if I’m going to Alaska.
I would recommend no lithium on the air port.
Haven’t you tested the batteries within high altitude?

On May 24, 2016 at 8:23am
Daniel wrote:

Is an exploding cell phone (LiPo/Li-ion) battery capable to blow op an ATX case (computer housing)?
Because of the vents it might not totally fireproof, but that is not really my issue if I put it in such a way that the blowup flame (I don’t know what the correct English word is) can’t set anything on fire.
My issue is that when it explodes it shouldn’t “fly” anywhere, because the wallls of the ATX case prevent it from doing so.
Therefore I want to know if an exploding battery is not capable to blow up a computer case.

On May 24, 2016 at 3:06pm
Simon Gore wrote:

On a note of personal experience. I had a smart phone li-ion battery that was ‘killed’ dead by a ravenous phone. It would not recharge. On metering the output it had a low voltage (under1.5V) and immeasurably low current .It hadn’t been used for months. So as you do when your a curious bugger. I took it outside,with ample fire protection and fire extinguishing and committed the earlier mentioned nail penetration test. Blow me down the thing started to fizzle and sputter with rank burnt plastic smoke and a tiny sustained fire. .no surprise to many of you I’m sure. Lesson 1) A ‘dead’battery can still produce enough current to ignite it’s internals when punctured .Observing the ‘arc’ more closely I could see the discharge was across small terminators from one cell division to the other. So I stabbed the battery multiple times to see what happened. No not a quicker bigger fire,but the cells had been disconnected across the battery and it was no longer able to generate enough current to arc/ignite.Lesson 2) The one break will cause fire.Many breaks will disrupt sufficient current flow.  All that said and done with many rolling eyes. Would this be a suitable method in battery design.When the heat gets OTT (thermal runaway) the cells connections disintegrate limiting available current ??  Just a thought? Any designers here ?

On June 12, 2016 at 10:17pm
graham wrote:


On June 23, 2016 at 7:24pm
F.Grace wrote:

Can Li Ion batteries stored next to each other explode or is it always an internal issue?  I had 4 rechargeable batteries in a case together and one exploded.  Trying to work out if it was because of how I had them stored.

On July 8, 2016 at 7:07am
R. Crim wrote:

Are there any known cases of a smoke alarm catching on fire due to the 10 year lithium battery?

On July 13, 2016 at 12:39am
Michele Rivarola wrote:

I am suprised you even refer to water when attempting to extinguish a lithium ion battery fire. Perhaps in the instance of a laptop or a single phone it may work but that is about it. Lithium like all other alkalis is reactive with water and produces an exothrmic reaction which generates hydrogen, not the type of gas one woud want when trying to extinguish an existing fire. I would have thought that the only available options would have been CO2 because of the cooling effect; DP will smother the fire but will not cool the battery down. Lithium on battery fires are a headache and difficult to deal with which is why many motor manufacturers that produce hybrids have steered well clear of this type of battery. And by the way Halon is a banned substance because of the ODP.

On July 13, 2016 at 10:57am
Will wrote:

I’m trying to add a Samsung battery back to my e-bike with the same voltage at 36V, 4.4A.  Unfortunately, there is no room in the stock battery compartment.  If I ran a Y adapter cable out of the box for the additional Samsung battery, what is the best way to carry the batt on my bike?

Would a plastic holder be best or would even a bike bag attached to my seat post be ok?


On July 14, 2016 at 7:52am
Rock wrote:

I have a product that users wear on their heads and uses 18650 batteries. Are there any known risks having batteries near the head for long periods of time?

On July 19, 2016 at 12:29pm
Pamela Rickman wrote:

My Li-ion battery leaked (looks like small fluid leak) on the battery door at the bottom of my Nikon D7000. I was out photographing sailboats at noon on HOT summer day. From all I’m reading, that battery should be disposed of. What can I use to clean the inside of the battery door of the camera? Is it safe to put a brand new battery in the camera? Electrodes at the top of the compartment do not appear to be involved.


On July 23, 2016 at 4:20pm
Plamen wrote:

I wanted to reuse the LiPo battery of a broken chinese-no-brand tablet, so I took it out. But is was heavily glued to the display, so in the process a patch of the protective foil’s outer layer was torn off. Is it safe to try and use the battery like that? Surely, there must be more than one layer of protective coating? At least it looks the same underneath the torn patch.

On August 22, 2016 at 3:27pm
Noah wrote:

I just got back from a hunting trip and I had two LG 18650 blow up. I had them in a pocket that was in the top of my pack-frame, (next to my head). by the grace of God I was picking it up to put on when they exploded, they burned my pack-frame badly and put a hole in the table it was leaning on. If I had put on the pack seconds sooner, I would be blind or worse, dead… Why did this happen??

On August 22, 2016 at 4:33pm
Josephine wrote:

My son just started driving home from work when he notice smoke coming from the back tub of his ute, he stopped, got out and before he knew it the whole car burnt down. Could this have been caused by one of the batteries of his hand tools? His tools were Milwaukee and were bought brand new just over a year ago.

On August 30, 2016 at 8:37pm
Warren wrote:

I’m looking at some products using China-made lithium batteries. They are using 18650 cells. What should I be looking at (certificates, characteristics ect) to see whether the batteries are good? My main concern is safety, I don’t want the products to start burning up after I sell to consumers.

On September 1, 2016 at 10:49am
Roger Bohn wrote:

Some quick comments.
Rick: Main battery risk is fire, but fire on the head is not nice.

Pamela: Camera should be fine. I have used a small a steel brush to clean residues, but I don’t know what yours looks like.

Plamen: Please,  throw it away. If too reluctant to do that, get some electrical tape and cover the break with that.

Noah, wow. Can you say more about how they “exploded?” Usually they get hot, then burn, then explode in that order. Also, what brand were the 18650s?? See Warren’s question.

Josephine: Yes, it’s possible, but it’s unlikely unless one of the batteries was physically damaged e.g. by being dropped.

Warren: I share your concern about 18650s. Read around on other forums. For myself, I get double-protected batteries from “real” brand names (well-known electronics companies). But they are much more expensive.  “Made in China” is ok but “Made by Chinese no-name company” is not. Of course, counterfeits of the expensive brands are possible - there are some examples on forums.
  I wish I knew a better way to figure out which brands/models are safe.

On September 17, 2016 at 4:59am
pat george wrote:

I fly commercially and private carrier all of the time; should I feel a danger in using my blackberry phone and the battery catching fire?  Some pilots are suggesting not using and putting in fire proof box, I think there is more danger with airplane mechanics than my phone?

On September 18, 2016 at 9:43am
Richard wrote:

Is there a test on Li chargers for over voltage and voltage transients.

On September 23, 2016 at 6:32am
Mrs Julie Smith wrote:

I heard on the news about a baby eating a litthuem battery and I was wondering if they could be incased in a container and then you replace the container and the battery so no need to even touch the old battery so even if the old battery leaks it won’t affect the product its in and I think that children’s toys should be like they did with plugs silled units so that you can not be changed

On September 23, 2016 at 10:21am
fernando wrote:

the ,0% charge lithium ion batteries still will burst into flame if handle improperly?

On September 24, 2016 at 10:48am
Richard wrote:

Does the University do testing of Li batteries ? if so, Do you test for over voltage and
Transient power supplies? Richard

On October 16, 2016 at 3:12pm
Linda Schaub wrote:

Hello - I live in Southeast Michigan.  After the horrible Winter of 2013-2014 and 2014-2015 my handyman I’ve had for twenty years retired. He had been doing the snow at my small house for over 20 years.  The snow services wanted $25.00/each visit and Bill had charged $150.00 for the entire season.  So, I bought a Snow Joe cordless, lithium-battery powered snowblower (Model iON18SB) at Lowe’s in June 2015.  The salesman put it together and I got it home and never used it last year - very little snow.  I only bought it to save $$ and because heart disease runs in the family, and I was 59 years old and hadn’t shoveled snow in 25 years.  Salesman said it was okay to leave it until November of 2016 and fully discharge battery before charging it.  I just read all the directions, watched a great tutorial on YouTube, but, I have a niggling worry about the lithium battery overheating and burning up like the recent Samsung Note phone.  My other worry is that because I work from home, I don’t use my car very much - it is parked in the garage 99% of the time (7 years old, 3,300 miles) with a battery trickle charger on it.  I intend to charge the snowblower battery in the house, but worry about having the battery, once charged, near the trickle charger.  I had no problems shovelling the snow last year (albeit not very much) and am seriously wishing I did not buy this snowblower and stuck with the electric Snow Joe, but salesman said “dangerous to use electric cords around snow/wet” ... am I wrong to worry?  If I could sell the silly thing I would, but I have no family members who might want it, and any neighbors already have their own snowblowers.  I apologize for this long (and potentially rambling question) but I hear so many scary things about lithium batteries these days.  I work from home and use my laptop all day long, but I do shut it down to cool the laptop every four hours because of my concern of overheating.  Could I get your opinion on whether this machine is safe to use with the battery please?  I think I should have relied on my shovel, but since I was nearly 60 years old and with heart disease (my grandmother and her 8 siblings and my mom had an irregular heartbeat) I didn’t want to take any chances.  Sincerely, Linda Schaub

On December 6, 2016 at 2:45am
Muan wrote:

I just bought an i phone battery and when i inspect the battery saw there is a crack on the cover…..will it be allright if i use it?

On December 6, 2016 at 5:15pm
Richard wrote:

Is there a test on Li bateries for over voltages

On December 9, 2016 at 7:23pm
Rob wrote:

I recently bought rechargeable AA 1.5V JUGEE Lithium batteries from China. My idea was to use them in outdoor trail cameras. Are you familiar with this brand and any safety issues they may pose. Also, is there a danger leaving them in a trail camera long after they have discharged. I’ve heard a long period of discharge could be possibly hazardous to the battery causing it to become very hot. Considering using them only during the winter months. Any reply would be appreciated.

On February 4, 2017 at 8:43am
Kenneth Freedman wrote:

There seems to be some confusion in the comments here between so-called Lithium Polymer and so-called REAL Lithium Polymer batteries.Lithium Polymer batteries are just as “unsafe” as Lithium Ion, in that the polymer is embedded with a liquid, whereas the so-caleld REAL Lithium Polymer is not. This type of battery is still under development, but is remarkably resistant to combustibility issues.

On March 15, 2017 at 4:12am
Anil R Kurup wrote:

I have this crazy hobby of Aeromodelling, Quadcopters etc, and this have accumulated a couple of LiPos in my collection. 2s X 1 and 3s X 2 numbers. After reading about LiPos and how ‘mischevious’ some of these can be, I am scared about leaving them at Home and going to Office, travel etc. Though I never leave them unattended while charging or discharging(for Storage), jus’ wanted to ask if its really safe to leave them at home in LiPo safe bags(all three in separate Lipo bags)? Thanks in advance. My friend advised me to put it inside a pressure cooker with some silica gel within to arrest humidity.  Does it sound funny, or makes sense? He tells the pressure cooker has a safety vent on it,which helps to vent out and relieve itself without pressure buildup, and also is strong to take mild explosions.
Any comments?

On March 25, 2017 at 7:04am
Hi wrote:

I use knife to destroy a li-ion battery but then it give smoke. How should I dispose it without explosion?? Help

On April 9, 2017 at 11:18am
Tanya wrote:

Fully charged my Kobo Arc tablet last night, in the completely turned off state. My son went to turn it back on this morning & all of a sudden the entire room filled with thick, heavy smoke; which was pouring out of the tablet!! Are there any health concerns we should now worry about?? Despite the fact that it took roughly 1.5 hrs for all the smoke to fully dispel & the fact that the entire device pretty much melted away due to the heat, my husband’s first instinct was to take it outside to the snow bank. He has some minor burns on his hands, but I’m more worried about all of the smoke we all inhaled! Both my son & I have asthma, as well. Any advice is greatly appreciated!!

On April 28, 2017 at 5:55am
Monte wrote:

My lithium ion battery leaked a little clear fluid is my battery bad?

On May 2, 2017 at 7:16am
Diana wrote:

Can anyone share information about the safety research of 10 year lithium batteries (sealed or not sealed) in smoke detectors (wired or battery only)?

On June 15, 2017 at 10:08pm
Steve Lopez wrote:

My NEW DELL Inspiron 13 7000 of 4 months got very hot on bottom then smoke came out of side ports.  The unit was NOT plugged into AC at the time.  I immediately took it outside expecting it to literally blow up.  Didn’t and when cooled down I tried to us it.  Battery was dead but worked ok on AC.  After hours of diagnosis it was determined the battery failed.  Very poor support from Dell to replace the battery but my concern here is to notify all and everyone of this incident and see if there is a bigger problem among laptop users, DELL or otherwise.

On July 25, 2017 at 1:22pm
Robin wrote:

Yesterday I experienced an apparently spontaneous lithium-ion battery fire.

I purchased a portable MP3 player on eBay from a a Chinese seller. On Sunday I charged it via USB and transferred some music to it. Used it on Sunday afternoon and evening.

On Monday morning I took it to my home office, leaving it on a desk. It was not connected to anything and was switched off.

I had my back to it whilst I was working and suddenly became aware of a hissing sound, turned around to see smoke pouring out of the player. Without thinking I grabbed it and threw it out into the garden.

It continued to hiss and smoke, completely melting the player and destroying my new 128GB micro-SD card.

Needless to say I am rather shocked by the incident. If I had not been there to take action, I have no doubt that this would have caused a major fire in my property and I was lucky not to suffer burns.

I am an electronics engineer and thought that Li-ion batteries were safe unless mishandled.

Nothing that I did with the player should have caused the battery to fail so it seems to have been caused by a manufacturing defect.


On August 27, 2017 at 5:30am
Gurdeep Singh wrote:

This issue is still as relevant this year. With Samsung and Panasonic recalls showing potential for battery fires from Li ion batteries are real. Dell on the other hand have chosen to keep quiet their own manufacturing problem on their Dell XPS models. Those laptops have a higher than average chance of batteries expanding within their casing leading to situations where consumers see their laptop cases distorting and their trackpads lifting away. The worrying issue is that Dell are choosing to ignore this citing warranty expiration as a valid reason to walk away from their safety responsibilities. One example can be seen at www.mod-gadget.com/dell-xps-laptops-widely-suffering-from-swollen-battery/ but there are plenty more on both the web and twitter.

On September 26, 2017 at 6:51pm
D. Jacobs. wrote:

-I wonder what the risk is with a first generation iPad that is laying unused a lot with fully charged battery on it - should I be worried that the battery can go bad ?

- Same with another little used android tablet (Lenovo)?

- Also an old laptop with flat Li-Ion battery ?

On November 21, 2017 at 7:04am
Philip wrote:

Many people seems to be confused. There for a little summairy here:

LiPo = Lithium Polymer = Hoverboard = RC-Toys This battery should not be charged in your house or bedroom. You also need special glasfiber bag to store and charge this battery. Only charge at unflameble surfaces. This battery can also used in drones, rc-toys, cheap tablets, phones, powertools even cheaper ebikes etc. When in use charging and discharging or when used you should always be near of them !!! Store always out of the device (if possible) in a special bag for Lithium Polymer batteries/accu’s. DO NOT CHARGE THESE AT HOME OR BEDROOM OR GARAGE OR WITHOUT BEING AT HOME!!! Only charge and use/discharge them when (adult) present.

Lithium-ion ( LiCoO2 / LiMn2O4)  are used in ebikes, laptops, tablets, 18650 cells etc. Are safe if handled normal and woking normal. But need special dedicated charger which is always delivered with the device. Sometimes you can use other charging devices like USB-loaders, but often the are NOT as save as the original charger. Lithium-ion is considered SAFE.

But old or not good Lithium-ion cells/batteries or accupacks can be dangerous! They can take a charge, but they also can have a defect which generates heat, a small short. These cells can reach a high temperature and can other cells heat up in a pack. This is dangerous. They can fent, burn and or explode and set flameblethings like carpets, clothes and furniture on fire. Early warnings are warm at touch or very warm. Disconnecting a charger is not enough! The reaction will go on until the cell is dead again!!! So a fire hazard is still there bring them outside.

If you like MORE safe batteries consider LiFePO4 these are more safe than Lithium-ion and also have a much longer lifespan. 2000 cycles instead of 300-500 for Lithium-Ion’s

Tip for MUCH more safety is: don’t stress your battery. Don’t quick charge. This gives more stress and even more worse is quick charge and use (heavy) your device. When your device is working and battery is empty it is better to cool down first before recharging. Don’t put laptops (when working hard) on surfaces like carpet, bed or tablecloth. If you are liking to play games or do heavy computing work use normal power supply (110v/220v) Don’t charge and play at the same time. This gives a lot of heat and stress to laptop and batteries. Heat will quicker destroy your battery.

On January 8, 2018 at 6:43pm
Randy wrote:

I have a off-road ATV and I am sure that there must be a lot of vibration is a lithium battery good in this type of vehicle

On January 9, 2018 at 5:11pm
Gordon Craig wrote:

I know the core reason that li-ium batteries catch fire or explore.  Since back in the mid ‘80s, we created the problem, I thought that I should try to fix it.  It took me about an hour to figure it out, 1 minute to test out my theory.  Now I need a testing lab so that I can prove in a laboratory that I am correct.  I live in Utah so it would be easier for me to test here.  If you know of anywhere I can go, or if any of you are interested in learning more, lets talk business.

On February 8, 2018 at 9:52am
jay roberts wrote:

I have a brand new lithium-ion Led Spotlight I keep in enclosed room. It gives off a Burned smell ( like a motor burnout ) is this normal? Safe? or should I get rid of it? The smell gave a sore throat.

On February 12, 2018 at 4:44pm
Dana wrote:

Am glad to find the webpage.  I am an inventor and have a need for 12 volt underwater.  Am wondering in fresh water if 18650s or PiPo 12V are dangerous or will have issues? 

Such as this one https://www.amazon.com/Lithium-Phosphate-Battery-Kawasaki-KLR650/dp/B00SA630UI/ref=pd_ybh_a_4?_encoding=UTF8&psc=1&refRID=54VB239994K6XXFPCBYJ Could I put such a battery underware 20 feet in freash water as is?


On February 14, 2018 at 12:28am
You People are insane wrote:

Have you all been hiding under your beds from the last time your laptop got warm?

Lithium Iron Phosphate RV house batteries do not pose the threat lithium ion does. Look it up and read it. Chances are NONE of you have, including the moderators.

“The lithium-iron (LiFePo4) battery has a slight edge over the Li-ion (LiCoO2) battery for safety. This is important because a battery should not get overheated or catch fire in case of overcharging.

The lithium-iron battery has superior chemical and thermal stability. A Lithium-iron battery remains cool at room temperature while the Li-ion may suffer thermal runaway and heats up faster under similar charging conditions.

LiFePO4 is a nontoxic material, but LiCoO2 is hazardous in nature, so is not considered a safe material. Disposal of Li-ion battery is a big concern for the manufacturer and user.

On February 14, 2018 at 12:30am
You People are insane wrote:

By the way…

“A lithium-iron battery is also a rechargeable type of battery but made with lithium iron phosphate (LiFePO4) as the cathode material.

While lithium-iron is a newer version in the lithium battery family, its anodes are also made up of carbon in batteries.

Phosphate based technology possesses superior thermal and chemical stability which provides better safety characteristics than those of Lithium-ion technology made with other cathode materials. Lithium phosphate cells are incombustible in the event of mishandling during charge or discharge, they are more stable under overcharge or short circuit conditions and they can withstand high temperatures without decomposing. When abuse does occur, the phosphate based cathode material will not burn and is not prone to thermal runaway. Phosphate chemistry also offers a longer cycle life.

Lithium Iron Phosphate (LiFePO4 ) characteristics:

        Most stable
        Good density
        Long life

Any questions?

On February 14, 2018 at 10:20am
Gordon Craig wrote:

None of you get it
The real problem is that it’s a big no-no to charge and discharge a battery at the same time. Simple electronics 101.
Your phone or whatever runs off the battery even when it’s charging. That is what causes the initial damage. After the battery is already bad, what’s it going to do but overheat. Lots of examples over the last 30 years of this.

On March 29, 2018 at 9:02am
tony stewart EE since 1975 wrote:

There are many naive and misinformed people that must accept consequences if ignorant. 

Is it safe to walk across the street at night with traffic? Yes and No.

Battery Life expectancy reduces orders of magnitude with any stress;  These are exponential.  Safety data sheets will descibe the toxic risks of over exposure. There are many if you ignore warnings.  Safe disposal is paramount for the next generation.

Stress can be; Climate (moisture), self-induced thermal, mechanical, and Electrical over current/voltage and under voltage.  Every family of products has different characteristics.  While Mitsubishi gaurantees 10 yr life in their chemistry and design for batteries in their e-car. Ebay batteries with no reliability specs are pot-luck. Be concerned about where you buy batteries from, if there is no traceability for recall.

To G Craig , If your phone runs off the converter from the battery while another converter charges the battery, the net charge to the battery is reduced not increased. Although now you have twice the heat losses from both converters operating so for that reason, dim the display to a low setting for lower losses and extended battery time.

On May 16, 2018 at 11:35am
MicB wrote:

1) What should I look for to be sure a phone battery is certified?
2) For EV/hybrid car batteries, is there a standard way to fully discharge them after a crash, when storing the vehicle damaged, or when scrapping the vehicle?

On May 16, 2018 at 12:10pm
Gordon Craig wrote:


The only time I had a problem with a battery was back in the early 2000’s when I hooked a surge protector into an outport of a UPS.  Total melt down and fire.  Surge protectors are made to reduce the size of the syne wave and UPS’s use a syne wave to detect loss of power.  So while the UPS is creating syne waves, the surge protector is trying to muffle them in an infinite circle.
Now, if you look up the way li-ion batteries work, they always note that they cannot be charged and discharged at the same time.  Nobody but I reads the small print:-).
Also, you mentioned that the charge in the battery is reduced.  Not so.  Plug in your phone and start using it at 50% power remaining.  With several hours of user interface, the battery will be more charged that when you started.  But, this is totally off the mark.
Its not the amount of charge the battery contains, its that batteries are just not built to charge and discharge at the same time. 
The fix is easy.  Think about how your earphones work when you plug them into your phone.  What happens to your phones speakers.  they are automatically turned off.  Its a far simpler design then what you need to do to batteries but the logic is the same.
so, instead of charging the battery and using that charge to power the phone, while charging the battery, bypass the charging circuit and go straight to the phone.  When the battery is being used to power the phone ( and nothing is plugged into the wall), the bypass circuitry is disabled.

On May 31, 2018 at 2:49pm
James wrote:

Can you be electrocuted using a 20 volt rechargeable lithium ion battery hand tool while standing up in the water and working on a structure above the water?

On May 31, 2018 at 3:38pm
Cadex Electronics Inc. wrote:

Conditions for a serious, yet still potentially lethal, shock across a critical path, such as the heart, are:

- More than 30-V root mean square (rms), 42.4-V peak, or 60 V dc at a total impedance of less than 5000 ohms.     
- 10 to 75 mA.     
- More than 10 J.

On August 9, 2018 at 7:58am
Claudia Satchell wrote:

I have 2 electric bikes and must remove the batteries when bikes are in car racks. What should I store them in? I don’t want to leave them loose.

On August 24, 2018 at 6:43pm
Steve wrote:

LiFePO4 is great for all the reasons stated above as “Are people insane” stated.  What he didn’t state is that the contain about 1/2 the capacity per unit weight of Li Ion.  Thus, many users that require the lightest battery will not be using LiFePO4 technology.

On August 24, 2018 at 6:49pm
Steve wrote:

@Claudia Satchell   Think of batteries as your pet, anything you don’t expose your pet to, you shouldn’t expose the loose batteries from your Electric Bikes to.  Provide a vibration free environment with moderate temperature (much like you would like) and they will be fine.  If you have a container to prevent impact damage, that may also be a good investment.  I can understand why the EB requires removal prior to carrying on a bike rack after seeing one vibrate harmonically with the road.

On August 24, 2018 at 6:58pm
Steve wrote:

For those who have questionable cells (damage or concerned performance) and realize the life is past for them, they will remain unsafe until they are fully discharged to 0 Volts.
This can be done safely on single cell basis with a resistive load which can take the heat.  Perform this outside so if it catch fire, no loss will occur.

On the other hand if you have many cells where the resistor would be too large to be practical, consider using a metal pail and salted water to discharge the cells in.  About 1/2 cup per gallon will provide an adequate electrolyte to resistively discharge the cells.  The water also serves to keep the cells from overheating.  Although this sounds like the best method, you must deal with the liquid when the cells are discharged.  If nothing other than discharge occurred, kill the weeds with salt water, otherwise hazardous waste may be needed.

On October 3, 2018 at 9:42am
Judy wrote:

Improvements are being made to lithium-ion batteries every day, but we are still a long way from total safety. There is also emerging new technology for suppressing battery fires that does not require the use of liquids or Halon. https://cellblockfcs.com/ped-pad-2/

On December 12, 2018 at 5:08pm
Kevin wrote:

I work for a government agency that routinely destroys used cell phones for security reasons. We have recently come across a vexing problem with a certain Blackberry model that has a built in Li battery not designed to be replaced. The problem is, it’s almost impossible to remove these batteries without causing damage to the cells before we destroy these units. We recently had an incident ( fire ) which has resulting in a shut down order until a safety protocol can be established. Any suggestions?

On December 15, 2018 at 1:48pm
mary wrote:

Should I be afraid to give my grandson a relote control car with a lithium battery ?

On December 17, 2018 at 11:56am
Steve McMullen wrote:

No problem giving your grandson a remote control car Mary,  The systems have protection to protect the unit.  Just don’t let him keep on charge without observation (at night).  That would provide an extreme safer car.

On December 20, 2018 at 11:25am
Frank N wrote:

I am working on a project that requires 10,000 mAh 4S lipo to be sealed inside 700 cc enclosure to keep it waterproof at 10 feet of water depth.  I am concerned about the overpressure form a battery explosion fragmenting the enclosure when the device is above water and there are people nearby.  What kind of (worst case) overpressure could be expected if the fully charged battery is punctured in this 700 CC enclosure?  I am thinking we need the case and latches to be strong enough able to fully contain the overpressure or have a fast acting release valve or spring loaded latches that can deal with the flow rate before the overpressure becomes too significant.  Are there overpressure release valves that are made for this purpose?

On January 23, 2019 at 6:13pm

A lithiated anode (LiC6) would contain a lot of Lithium metal, and would be present during a discharged state. My question is that if an external fire occurred near a discharged Li-ion battery whereby the anode became exposed to the atmosphere, then water-based fire extinguishing would cause the Lithium metal (deposited on the anode) to react and generate H gas. Therefore, water should not be utilized in all Li-ion battery fire circumstances.

On February 3, 2019 at 6:51pm
Conor wrote:

Louis 4500 mAh 18650 batteries do not exist. These are usually imported from sketchy manufacturers overseas who lie about the batteries capacity. They usually test out around 600-800 mAh each. My point is please don’t trust these off brand manufacturers who lie about the capacity to sell you a safe battery. Only use LG, Sony, Samsung, Sanyo, Efest, and others in that class of manufacturers.

Best priced 18650 from US distributers may be Samsung 30G (3125 mAh) at around 900mAh/$1

Order original brand 18650 batteries on Alibaba for around 1100 to 1300 mAh/$1 make sure to order from reputable distributers.

Never buy a 18650 battery claiming to be over 3500 mAh - it doesn’t exist at the moment.

On February 4, 2019 at 1:38am
Heath wrote:

This is absolutely not how to extinguish a lithium polymer fire.  I’ve just had my rc lipos catch fire and a class d extinguish done absolutely nothing.  I then deployed a class b.  And it stop the flames from coming from the batteries.  Lucky I had read other website information on the subject otherwise there would have been a lot more destroyed in the fire. How this can be a the first thing that pops up on google when you type in “how to extinguish a lipo fire” is appalling.

On February 14, 2019 at 4:01am
Tord S. Eriksson wrote:

Teslas catch fire, and so do model aircraft powered by Li-ion occasionally. No way you can put them out, and the health issues are very real.