Lithium-ion Safety Concerns

When Sony introduced the first lithium-ion battery in 1991, they knew of the potential safety risks. A recall of the previously released rechargeable metallic lithium battery was a bleak reminder of the discipline one must exercise when dealing with this high energy-dense battery system. 

Pioneering work for the lithium battery began in 1912, but is was not until the early 1970's when the first non-rechargeable lithium batteries became commercially available. Attempts to develop rechargeable lithium batteries followed in the eighties. These early models were based on metallic lithium and offered very high energy density. However, inherent instabilities of lithium metal, especially during charging, put a damper on the development. The cell had the potential of a thermal run-away. The temperature would quickly rise to the melting point of the metallic lithium and cause a violent reaction. A large quantity of rechargeable lithium batteries had to be recalled in 1991 after the pack in a cellular phone released hot gases and inflicted burns to a man's face. 

Because of the inherent instability of lithium metal, research shifted to a non-metallic lithium battery using lithium ions. Although slightly lower in energy density, the lithium-ion system is safe, providing certain precautions are met when charging and discharging. Today, lithium-ion is one of the most successful and safe battery chemistries available. Two billion cells are produced every year. 

Lithium-ion cells with cobalt cathodes hold twice the energy of a nickel-based battery and four-times that of lead acid. Lithium-ion is a low maintenance system, an advantage that most other chemistries cannot claim. There is no memory and the battery does not require scheduled cycling to prolong its life. Nor does lithium-ion have the sulfation problem of lead acid that occurs when the battery is stored without periodic topping charge. Lithium-ion has a low self-discharge and is environmentally friendly. Disposal causes minimal harm.

Long battery runtimes have always been the wish of many consumers. Battery manufacturers responded by packing more active material into a cell and making the electrodes and separator thinner. This enabled a doubling of energy density since lithium-ion was introduced in 1991. 

The high energy density comes at a price. Manufacturing methods become more critical the denser the cells become. With a separator thickness of only 20-25µm, any small intrusion of metallic dust particles can have devastating consequences. Appropriate measures will be needed to achieve the mandated safety standard set forth by UL 1642. Whereas a nail penetration test could be tolerated on the older 18650 cell with a capacity of 1.35Ah, today's high-density 2.4Ah cell would become a bomb when performing the same test. UL 1642 does not require nail penetration. Lithium-ion batteries are nearing their theoretical energy density limit and battery manufacturers are beginning to focus on improving manufacturing methods and increasing safety. 

Recall of lithium-ion batteries

With the high usage of lithium-ion in cell phones, digital cameras and laptops, there are bound to be issues. A one-in-200,000 failure rate triggered a recall of almost six million lithium-ion packs used in laptops manufactured by Dell and Apple. Heat related battery failures are taken very seriously and manufacturers chose a conservative approach. The decision to replace the batteries puts the consumer at ease and lawyers at bay. Let's now take a look at what's behind the recall.

Sony Energy Devices (Sony), the maker of the lithium-ion cells in question, says that on rare occasions microscopic metal particles may come into contact with other parts of the battery cell, leading to a short circuit within the cell. Although battery manufacturers strive to minimize the presence of metallic particles, complex assembly techniques make the elimination of all metallic dust nearly impossible. 


Figure 1: Lithium-ion battery damages a laptop. 
Safety issues are enticing battery manufacturers to change the manufacturing process. According to Sony, contamination of Cu, Al, Fe and Ni particles during the manufacturing process may cause an internal short circuit.

A mild short will only cause an elevated self-discharge. Little heat is generated because the discharging energy is very low. If, however, enough microscopic metal particles converge on one spot, a major electrical short can develop and a sizable current will flow between the positive and negative plates. This causes the temperature to rise, leading to a thermal runaway, also referred to 'venting with flame.' 

Lithium-ion cells with cobalt cathodes (same as the recalled laptop batteries) should never rise above 130°C (265°F). At 150°C (302°F) the cell becomes thermally unstable, a condition that can lead to a thermal runaway in which flaming gases are vented.

During a thermal runaway, the high heat of the failing cell can propagate to the next cell, causing it to become thermally unstable as well. In some cases, a chain reaction occurs in which each cell disintegrates at its own timetable. A pack can get destroyed within a few short seconds or linger on for several hours as each cell is consumed one-by-one. To increase safety, packs are fitted with dividers to protect the failing cell from spreading to neighboring cells. 

Safety level of lithium-ion systems

There are two basic types of lithium-ion chemistries: cobalt and manganese (spinel). To achieve maximum runtime, cell phones, digital cameras and laptops use cobalt-based lithium-ion. Manganese is the newer of the two chemistries and offers superior thermal stability. It can sustain temperatures of up to 250°C (482°F) before becoming unstable. In addition, manganese has a very low internal resistance and can deliver high current on demand. Increasingly, these batteries are used for power tools and medical devices. Hybrid and electric vehicles will be next.

The drawback of spinel is lower energy density. Typically, a cell made of a pure manganese cathode provides only about half the capacity of cobalt. Cell phone and laptop users would not be happy if their batteries quit halfway through the expected runtime. To find a workable compromise between high energy density, operational safety and good current delivery, manufacturers of lithium-ion batteries can mix the metals. Typical cathode materials are cobalt, nickel, manganese and iron phosphate. 

Let me assure the reader that lithium-ion batteries are safe and heat related failures are rare. The battery manufacturers achieve this high reliability by adding three layers of protection. They are: [1] limiting the amount of active material to achieve a workable equilibrium of energy density and safety; [2] inclusion of various safety mechanisms within the cell; and [3] the addition of an electronic protection circuit in the battery pack.

These protection devices work in the following ways: The PTC device built into the cell acts as a protection to inhibit high current surges; the circuit interrupt device (CID) opens the electrical path if an excessively high charge voltage raises the internal cell pressure to 10 Bar (150 psi); and the safety vent allows a controlled release of gas in the event of a rapid increase in cell pressure. In addition to the mechanical safeguards, the electronic protection circuit external to the cells opens a solid-state switch if the charge voltage of any cell reaches 4.30V. A fuse cuts the current flow if the skin temperature of the cell approaches 90°C (194°F). To prevent the battery from over-discharging, the control circuit cuts off the current path at about 2.50V/cell. In some applications, the higher inherent safety of the spinel system permits the exclusion of the electric circuit. In such a case, the battery relies wholly on the protection devices that are built into the cell.

We need to keep in mind that these safety precautions are only effective if the mode of operation comes from the outside, such as with an electrical short or a faulty charger. Under normal circumstances, a lithium-ion battery will simply power down when a short circuit occurs. If, however, a defect is inherent to the electrochemical cell, such as in contamination caused by microscopic metal particles, this anomaly will go undetected. Nor can the safety circuit stop the disintegration once the cell is in thermal runaway mode. Nothing can stop it once triggered.

What every battery user should know

A major concern arises if static electricity or a faulty charger has destroyed the battery's protection circuit. Such damage can permanently fuse the solid-state switches in an ON position without the user knowing. A battery with a faulty protection circuit may function normally but does not provide protection against abuse. 

Another safety issue is cold temperature charging. Consumer grade lithium-ion batteries cannot be charged below 0°C (32°F). Although the packs appear to be charging normally, plating of metallic lithium occurs on the anode while on a sub-freezing charge. The plating is permanent and cannot be removed. If done repeatedly, such damage can compromise the safety of the pack. The battery will become more vulnerable to failure if subjected to impact, crush or high rate charging. 

Asia produces many non-brand replacement batteries that are popular with cell phone users because of low price. Many of these batteries don't provide the same high safety standard as the main brand equivalent. A wise shopper spends a little more and replaces the battery with an approved model. Figure 1 shows a cell phone that was destroyed while charging in a car. The owner believes that a no-name pack caused the destruction. 



Figure 2: A cell phone with a no-brand battery that vented with flame while charging in the back of a car.

To prevent the infiltration of unsafe packs on the market, most manufacturers sell lithium-ion cells only to approved battery pack assemblers. The inclusion of an approved safety circuit is part of the purchasing requirement. This makes it difficult for a hobbyist to purchase single lithium-ion cells off-the-shelf in a store. The hobbyist will have no other choice than to revert to nickel-based batteries. I would caution against using an unidentified lithium-ion battery from an Asian source, if such cells is available.

The safety precaution is especially critical on larger batteries, such as laptop packs. The hazard is so much greater than on a small cell phone battery if something goes wrong. For this reason, many laptop manufacturers secure their batteries with a secret code that only the matching computer can access. This prevents non-brand-name batteries from flooding the market. The drawback is a higher price for the replacement battery. Readers of often ask me for a source of cheap laptop batteries. I have to disappoint the shoppers by directing them to the original vendor for a brand name pack.

Considering the number of lithium-ion batteries used on the market, this energy storage system has caused little harm in terms of damage and personal injury. In spite of the good record, its safety is a hot topic that gets high media attention, even on a minor mishap. This caution is good for the consumer because we will be assured that this popular energy storage device is safe. After the recall of Dell and Apple laptop batteries, cell manufacturers will not only try packing more energy into the pack but will attempt to make it more bulletproof. 


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On November 12, 2010 at 11:47pm
Eric Boyer wrote:

I was planning on building a high-powered portable stereo with built-in lithium-ion batteries from an Asian source and a custom-made charger. But, now that I’ve read this article I definitely won’t be doing that! I’ll probably use a power tool battery and its charger instead.

On February 17, 2011 at 9:57pm
Manoj wrote:

Can we use lithiumion batteries for UPS systems

On April 14, 2011 at 2:25am
Amada Zhang wrote:

of course you can.
Before you use lithium battery, please make yourself have enough knowledge on Li-Ion rechargeable batteries in charging, discharging and assembly. And you should follow the instruction, what you can do, what you can’t do.

On April 14, 2011 at 3:25am
Eric Boyer wrote:

Actually many of the articles here on that discuss lithium batteries suggest that they are not well-suited for UPS systems. UPS systems keep their batteries fully charged at almost all times so that they are ready when they are needed. The lifetime of lithium batteries is reduced fairly significantly if they are kept fully charged at all times (see . Even one of the articles on your website shows that lithium battery lifetimes are significantly reduced if kept at full charge: see the table on, which I hope you used with permission from because otherwise that is copyright infringement). Therefore, lithium batteries are not suited for UPS systems.

Lead-acid batteries are still the chemistry of choice for UPS systems. They are the only major battery chemistry that actually likes being fully charged and hence is well-suited for UPS systems.

Lithium batteries are dangerous and you should NOT design them into a product unless you are an experienced battery professional. In fact, it is illegal in many countries to use lithium batteries in a consumer product unless licensed to do so. Also, it is illegal in many countries to sell bare lithium cells to the general public (that is, lithium cells without any protective circuitry) because of how dangerous they are. Even small lithium batteries, such as cell phone batteries, are capable of significant damage to yourself and your surroundings if mishandled; a UPS full of lithium batteries would be positively catastrophic if designed improperly.

Amada Zhang, please do not tell the general public that they are ok to use lithium batteries. Telling someone to make sure they “have enough knowledge on Li-Ion rechargeable batteries in charging, discharging and assembly” is not adequate and misleading; only licensed professionals are capable of obtaining enough knowledge on this subject. In addition, almost no bare lithium cells come with “instructions” because the only people who should be buying bare lithium cells already know how to use them.

On April 26, 2011 at 10:54am
George wrote:

This looks like an informative and useful article. One thing that seems to be missing from it, however, are citations. I see a few citation links ([1], [2], etc.), but those don’t actually correspond to any visible citations within this article. Any chance those could be added in?


On May 26, 2011 at 9:25am
Tanya wrote:

How do you decipher the bar code on a battery to find out additional information?  The bar code I am trying to find more about is a Sony battery:  11S92P1174Z1ZF0988L6FP.
Any help would be greatly appreciated.

On August 8, 2011 at 5:50am
pyroslav wrote:

@ Amada Zhang U just keep telling it is ok for people to use Li-Ion in their own aplications, if they “feel” they are knowledgable enough… It s ok for personal - hobbyst to build that kind of stuff, just don t sell potentally dangerous devices to others, u might be legally and centanly morally responsible if something goes wrong. Manny RC hobbysts allready do so, so it s pointless to discusscthis any further.

So please no 8ull5h1tt1ng about dangers of ANY kind of batteries any more, sure u have to be carefull, but, for example, gasoline and gasoline powered engines are much more dangerous, and u wouldnt tell people not to fix their own carc, trucks, lawnmowers, etc.

One thing to do - allways “pack” big battery banks in a way (no matter what chemistry) so that in worst case scenario there will be minimal damage to anything beyond batteries, and u have nothing further to worry about safety.

On January 1, 2012 at 10:50am
Paryinvalia wrote:      Louis Vuitton Handbags

On March 20, 2012 at 12:56pm
Chris C. wrote:

Eric Boyer and pyroslav: Reading all the comments in this excellent article and elsewhere on this very informative site, it really, really bothered me to see the unnecessary, politically correct BS (“8ull5h1t” , as you say so eloquently, pyroslav) that you guys felt you had to proffer in so many long and drawn out sentences.

If it wasn’t obvious people who come here for information are hobbyists looking for in-depth knowledge here and elsewhere, obviously doing their own research before embarking on such a project, I don’t know what more needs to be said.

Amanda Zhang said exactly what needed to be said: that these batteries are perfectly suitable for UPSs, provided they are used wisely and according to the warnings expressed here and elsewhere.

What part of “Before you use lithium battery, please make yourself have enough knowledge on Li-Ion rechargeable batteries in charging, discharging and assembly” did you feel was not explicit enough?

On May 20, 2012 at 7:15am
Victorine O. wrote:

I read this article with great interest as the lithium-ion battery in my Hewlett Packard laptop exploded a few months ago. It was horrific and flames were firing continuously from the battery like from the back of an aircraft engine. After my partner managed to stop the fire, it then exploded a SECOND time 10 minutes later causing more fire and material damage. My battery was not part of the recalls from Hewlett Packard so it means that this could happen again to someone else as there are still faulty batteries out there… What I am interested to know is what impact these chemicals can have on our health after inhaling the vapour and dust caused by the explosions and fires? We are very concerned by the risk of contamination as our 4 month-old baby was only 1.5 metres away from the first explosion!
Thank you for your help.

On May 20, 2012 at 1:23pm
Chris C. wrote:

Here’s what a quick search turned

On August 13, 2012 at 9:06am
linda wrote:

my husband has a few questions i can’t seem to find answers to in this article- hoping for some help from this forun. thank you in advance. 1. is there a limit in size to this technology? 2. can they be used in series or parallel? 3. can they funtion built as a flat panel? 4. what is the largest size they can be bought in?

On September 13, 2012 at 7:33am
Michi wrote:

Who wrote this text? I like it and would like to quote it. smile PLZ answer fast.

On October 16, 2012 at 12:25pm
Meg Butler wrote:

A designer just made a phone that runs on sugar for Nokia!

On November 23, 2012 at 10:56am
Amit wrote:

I was planning to make a product based on GSM modem , Li Ion is preferred in most such products , but some products are also using Lead acid ,  however is it possible to use
Ni mH instead , because that will be less bulky than , Lead acid , will that be safer

On January 1, 2013 at 10:39am
JoeB wrote:

From what I can read, these batteries are safe as long as they are use properly and for their intent.  My question is what could happen if they were puntured accidently, especially the ones used in our hybrid/electric cars, what would really happen if the car was involve in an accident where the batteries got punctured and contaminated with metal debris?

Is this a DejaVu where they won’t approach this area until something actually happens?  I.E. Ford 70’s Pinto where their gas tank would blow up if involve in a rear end accident and basically Ford and NTSB kept it hush-hush until the media found out about it then stop making those vehicles.

Doubt that they would since they Auto Manufactures-Federal Government are selling us this new format of transportation??

On January 21, 2013 at 11:08am
Mike Rudmin wrote:

Not related to Valence in any way, but quite impressed by the video of them shooting at a normal lithium ion battery, and a lithium-ion phosphate battery.  The phosphates are immune.  Spinel is less dangerous than most others.  Most are quite unsafe for puncture. 

On January 23, 2013 at 4:10pm
Charlie Scuilla wrote:

Maybe after the Boeing Dreamliner safety incidents (in 2013) the above Li-ion safety statements need to be revised.

On February 5, 2013 at 4:00pm
Eddie Lawso wrote:

OMG.. I just was reading the latest details at

This stuff sounds way worse than they are saying

On February 5, 2013 at 6:07pm
Charlie Scuilla wrote:


I visited the site you referenced - the site is BS -  Do not believe the site.  My question on this site - was that we might have to rethink about how we define the safety engineering information for the public.  We need to wait until NTSB finishes the investigation for the real story.

On April 5, 2013 at 5:14am
Chris H wrote:

Wow this is great information. I’m planning to use a ballistic EVO2 12 cell lithium battery in my small homebuilt aircraft (not a model). I want to take as much precaution with using it and wonder what you might suggest? I was thinking in addition to an ammeter and voltmeter, to monitor the battery temperature. How can I find out what protection circuit is built into this battery? Has anyone taken one apart? How does on pretect the circuit when starting requires major current, but then only only smaller amounts afterwards? Circuit breakers operate thermally and I am afraid would trip to late to prevent a VWF situation. Is there a quick reacting fuse large enough available that would manage the large current?
Thanks for your input!

On August 26, 2013 at 2:44am
Huseyin Keksin wrote:

How can I be sure about the quality of a non brand battery. I purchased a Li-ION phone battery one from China.

Declaration from reseller:
Battery is an indispensable power source for a cell phone. Therefore, if the battery runs out of power quickly, it really casts a damp over our phone usage. However, keeping an extra battery enables you to enjoy endless pleasure with your cellphone and this Battery would be your best choice. The battery bears the properties of high capacity and dependable performance. It is durable, reliable and lightweight to carry, so it is worthy of your ordering. It is compatible with Samsung i9500.


  High quality Li-Ion battery
  Best replacement for the original battery with comparable standby and talk time
  Keep an extra battery on hand for extend standby and talk times
  Integrated microchip prevents overcharging and lengthens battery life
  The best replacement spare battery for your phone
  Our battery is sent out with little or no power, so please charge it for about 4 - 6 hours before using
  The battery operation time depends on conditions such as: Transmitting power level, Signal (distance between the phone and the base station), Network parameters defined by the operator

Battery Capacity 3030mAh
Voltage 3.7V
Dimensions 6.3 x 5.5cm / 2.48 x 2.16”(L x W)
Weight 38 g / 1.34oz
Color Gold

Package Includes

  1 x 3030mah battery

On October 6, 2013 at 11:30pm
Ave wrote:

I bought 6 AA Lithium Batteries for my digital Nikon Camera
The batteries are blue and have this printed on them: Li-ion 14500 1200mAh 3.7V
The Ebay Description says:
Power Input: DC 11 - 18Volt
Circuit power : Max. 50W
Charge current range : 0.1~5.0A
Current drain for balancing Li-po : 1200mAh/cell
NiCd/NiMh battery cell count : 1~15cell
Li-ion/Polymer cell count : 1~6series
Voltage: 3.7 V
Net weight:19g
Package weight:28g
Packing content:
1 x Battery

I wish I had seen this article sooner. I had no idea batteries could do what this has done. I purchased 6 of these AA batteries new from a Chinese Seller named Seemmy999

The batteries came fully charged - which initially pleased me as the NiMH ones I last ordered on Ebay had to be charged before use.

I put them into my Nikon and the monitor came on like a brilliant flashlight - even though it was OFF~! I then turned it on and the imaging was all scrambled, so I removed them after trying to get the setup screen unsuccessfully. Then i turned it off and on and got the screen and saw a spot to adjust for Lithium batteries so switched to that but still the screen after attempting to take a picture, did the same scrambled thing, so i removed them, wondering if they were too strong. I then tried them in my Samsung camera - same thing, so took them out. initially i thought they were too strong so offered them to my son for his fairly new Xbox 360 controller, since he is always going through batteries fast.  He put them in and without turning it on, it made noise, started up and then it fried his controller which cost him over $60.
I put my old NiMH batteries back in my camera and it seems okay but his controller is toast.
I wrote the seller and they seem to want to be helpful but am not sure they really understand what I am trying to tell them and seems they may simply refund my purchase price, but now my son is out his new Xbox 360 controller - so not sure if this seller is going to do anything about that or not, kind of think not.

I suppose this all could have been avoided if I had known about this site before.  My 2 reasons for buying various things from China is #1 price and #2 figure they need work and sales too since their population is 20x that of the US. I have made friends over there and bought many things from there before but this is the first time I ever had any sort of problems with batteries other than them being dead.

My reason for wanting Li-on batteries is that my NiMh ones in my Nikon tend to wear out fast when using the flash so I had hoped the Li-on’s would give me more photo shoot time without changing batteries.

Boy was I wrong about buying Li-on’s from overseas and dont think I will ever buy batteries from there again.

On October 12, 2013 at 7:36am
MrWhite wrote:


Li-ion cells and Lithium cells are totally different stuff although they contain the same metal in them.

Li-ion cells are 4.2V when fully charged.
Lithium cells are non rechargeable and their max voltage is ~1.8V.
NiMH is about 1.4V.

Lithium cells should never be used on its own. It is extremely dangerous. I work in a company that builds Lithium Ion battery packs and have seen enough cells getting burnt.

Reason you don’t always see lithium cells on sale is because they have to be packed in a sealed pack along with its protection circuitry. overcharging and short circuits are catastrophic.

Also, don’t always believe in chinese Li-ion batteries. They can guarantee very high capacities, but they lack protection features most of the time. The lack of protection components (FETs) in the discharge path increases the actual capacity by a a mile.

On October 25, 2013 at 10:30pm
Photography Tour wrote:

However, keeping an extra battery enables you to enjoy endless pleasure with your cellphone and this Battery would be your best choice.

On November 5, 2013 at 11:38am
pedram wrote:

pls draw simply how to connecr some small batteries to make a correct pack for a laptop.

On November 5, 2013 at 11:40pm
Ave Hurley wrote:

Thankyou Mr White for all your info.
Just wish I knew earlier.
My son’s xbox360 controller was toast so he replaced it with a wired one. That ebay seller refunded the battery price but thats it. I wish ebay would enable warnings about these batteries.If they have any, I dont know where to find any such warnings.I will stick to using the NiMH batteries. I was lucky not to fry my camera, although it does have some damage as the features for some aspects I have now discovered no longer work, but for regular shots its still functioning.who would have guessed little batteries could do such damage~!

On November 6, 2013 at 4:02am
MrWhite wrote:


If you’re worried about buying batteries, then you might try the following:

Look or ask for a CE mark on the battery. If the Li ion battery is built inside the product, then it should have a CE mark on it. Usually CE batteries have additional many levels of protection and a fuse.

CE products adhere to strict safety requirements. There are of course other agency markings of higher demands.

Some products might have fake CE markings, so be aware of dodgy marking quality.

On December 2, 2013 at 2:01am
Maria wrote:


I am trying to find some common gas released from a Lithium Ion battery leakage. I wonder if anyone has info related this topic.

Thanks in advanced!

On December 2, 2013 at 2:16am
MrWhite wrote:


For lithium ion, there will be gasses if the cells is in contact with some water, moisture or other reactive elements. If so, the common ones would be hydrogen,carbon dioxide and carbon monoxide. But the actual ones depend on the type of chemical compounds used for the cathode and anode.

For nickel, it will produce hydrogen gases when overcharged. Since it is easier (less protection if compared to li ion) to overcharge nickel batteries, it usually has a vent hole to allow these gases to escape.

On December 2, 2013 at 3:41am
MrWhite wrote:


For lithium ion, there will be gasses if the cells is in contact with some water, moisture or other reactive elements. If so, the common ones would be hydrogen,carbon dioxide and carbon monoxide. But the actual ones depend on the type of chemical compounds used for the cathode and anode.

For nickel metal hydride NiMH, it will produce hydrogen gases when overcharged. Since it is easier (less protection if compared to li ion) to overcharge NiMH batteries, it usually has a vent hole to allow these gases to escape.

On December 2, 2013 at 7:50am
maria wrote:

Tks Mr White!

I belive for primary lithium batteries it will leak also SO2.

I am triyng to find a way to detect these kind of gases relases after batteries mishandling. Thats why I thouhg in the flammable compounds of the electrolyte. What do you think?

On January 2, 2014 at 8:07am
Kathy wrote:

In regards to the questions on possible gas releases, when the electrolyte is LiPF6, does anyone have test data on possible HF releases?

On January 27, 2014 at 5:05am
kai safran wrote:

My old mobile phone before I got rid of it was experiencing an unusual problem where it would spontaneously just turn itself off and then on again. Sometimes this restarting would happen so frequently that the phone would be unusable. When I took it to the network provider technician he said he fixed it & thought it was because of certain apps I had on it.Well several months later the problem came back, and I decided to upgrade to a new phone. One theory I have on why this problem happened is b.c of the cheap off brand Chinese batteries I used in it. Now that I’ve got a new phone I’m hesitant to use any of those cheap batteries that are all over eBay for fear they will ruin my phone. Has anyone experienced anything similar to this ? Perhaps someone would like to assure me of either the efficacy of these cheap batteries or the inherint danger of using them in phones ?

On January 30, 2014 at 10:56pm
Muraleedharan wrote:

Looking for some chemical to open the laptop battery case.

On January 31, 2014 at 12:20pm
Chris C. wrote:

Muraleedharan, I opened three different types all of them with my bare hands, just twist them open, using acetone you will melt the plastic but it is extremely messy and will most likely cause a lot of mess, be toxic to you and cause damage to the cells as well wink

On April 28, 2014 at 7:55pm


On August 10, 2014 at 6:55pm
Mr P wrote:

how can smartphone lithium ion batteries be shredded without any explosion? I mean like gently using hand tools such as scissors etc.. to tear it down….. ,before using a mill to completely reduce the sample pieces
      then also, what are the inventory materials of a smartphone lithium ion battery? I mean like the chemicals or metals used in making them. I really need this information but I was wondering how to get them, especially from a reliable source. Can anyone please help me?

On September 9, 2014 at 6:29pm
irfan ali wrote:

sir how we control and make safty on lithum ion

On October 25, 2014 at 9:42pm
myproject wrote:

there best way to shred them is in oil, also if they are fully discharged you won’t have heat generated, but oxidation depending on the humidity

On April 16, 2015 at 1:37am
Renish wrote:

Approximately, what will the rate of rise in temperature when the battery is in thermal runaway. ie: X degC / sec.

Also, can the thermal management strategy help to avoid thermal runaway.
ie: Switching on the chillers, Cooling fans etc.

This information I require from the point of Electrical Vehicles battery

On May 17, 2015 at 5:55pm
J. P. Burke wrote:

The information above has been very useful.  I’d like to see any further discussions about
lithium batteries used with electric scooters.  Where might I buy a “back-up” lithium battery for an electric scooter.

On May 18, 2015 at 5:03pm
Chris C. wrote:

No idea where you could buy one at a decent price, but if you have an existing depleted battery I see no problems in rebuilding it if you are handy and use proper safety practices, because there can be a lot of power left even in a defective battery as some cells may well be perfectly useable.

You definitely do not want to short them or overheat them, as they can then turn into bombs (or at least, combust very fast, juss imagine a pack of 48 together, throw safely far away if it happens, I’d only use a CO2 extinguisher or throw sand on top to control it.

As for cells, you can sometimes get deals for surplus laptop batteries for discontinued models and get the cells out of them for much cheaper than buying the raw cells, just make sure they aren’t too old when you buy them as cells age (I wouldn’t buy any batteries more than a year old, but some people have had good success with up to 5 year old cells)

On June 6, 2015 at 11:29am
peter connell wrote:

Just saying, in all the excitement it seems to have been forgotten that we have long had ok batteries. They were just so damn heavy. That’s the revolution,the root of all these marvellous new products like doable ebikes

For mobile apps they are a godsend. For stationary batteries, the chief benefit is irrelevant.

On June 7, 2015 at 11:18am
rahul wrote:

hello guys i am participating in a competition where we have to run a 3 wheeler(which will weigh around 250kgs with riders) with a BLDC motor (48 volt,350watt) and we have to reduce the weight as much as we can,so we are thinking of using a li ion it a good idea??? max power output is 400Watts. So, i want an idea about commercially available li ion battery i can use ,theri specification,cost ,everything anyone can suggest

On June 7, 2015 at 1:04pm
Chris C. wrote:

rahul, a lead acid battery for your application will add significant weight compared to a lithium ion battery pounds, depending on distance and weight it could add 100 kilos or more compared to lithium depending on the distance and track condition, you haven’t said how long it needs to work for.

In any case, lithium ion would be much lighter, but they are very, very expensive to purchase, perhaps you could get an endorsement from an ebike manufacturer and get several li-ion battery packs from them for free?

If you make your own from off the shelf parts, 18650 cells cost about a dollar and weigh about 10 grams per what hour… So let’s say 72 cells, 12 series of 6 in parallel, which will need to be matched and balanced, so let’s say you’d have to purchase 144 cells and put the others aside for spares or replacement… So let’s say about $750, maybe around $150 if you get your hands on good surplus laptop cells of the same brand and age…  Plus welding and assembling… a 72 cell battery would weigh probably around 3-4 kilos, whereas something that would supply sufficient power in lead acid would probably weight 75 kilos or so…

check this video for inspiration:
This guy made a 48 volt battery with 24Ah, so approximately 1KWh… For less than $100 of parts wink

The determining factor, it would seem, would be the relative weight of your driver and passengers… How heavy is the vehicle and what it is it made with? Can you shave weight there?

On June 7, 2015 at 11:53pm
peter connell wrote:

I am no expert but ab surprised i had never heard of these

pouch batteries

5C Rate Capable
160 x 230 x 6 (mm)
25 Ah

less than a4 & 1/2” thick = 25 amps - 4 x @1/” = 2” thick & 100ah.

6 mm? Thats not even 1/2”

On June 8, 2015 at 10:44am
rahul wrote:

@chris vehicle will weigh around 100kg with 2 driver of approx weight 70 each.we will be using some steel alloy to manufacture vehicle because of its good reparability and availability .
If you can tell approx difference that will come if we use li ion battery rather than lead acid to get 400watts power output ??

On June 8, 2015 at 8:28pm
Daniel P. wrote:


Very good paper about lithium safety concerns. I’m working in the development of lithium battery materials development field and I can garantee you that metallic particles is a major concern. Actually, the safest technology is the carbon-coated lithium iron phosphate. Capacity might not be as good as for their nickel or cobalt based counterparts (about 10% less), but they are safe as they won’t explode or burn when they go crazy (thermal runaway). What probably happens with “no-name” batteries is they are loaded with metallic particles. As you charge and discharge them, the metallic particles will migrate through the battery internal structure and puncture the separators. Which will be resulting in creation of internal short-circuits within the battery inner structure and may lead to thermal runaway reactions. Moreover, creation of internal short-circuits within the battery will reduce it’s service life and introduce memory effects within the battery (energy capacity degradation). Now the real challenge with these batteries is to decrease recharging time, without compromising users safety. It might be coming sooner than what most of people are expecting.

On June 17, 2015 at 7:30am
Peter R wrote:

we are a fire lab and we are planning a fire test with 500 Lithium batteries included in the fire load. what is your advice regarding safety?

On June 17, 2015 at 7:46am
charlie S wrote:

FAA did a similar test about 1-2 years ago at their Testing Facility in Atlantic City, New Jersey.  I would get a recommendation from them on you test setup, etc.

On June 17, 2015 at 1:28pm
Chris C. wrote:

rahul, here are a couple links you should find useful to help you out with your design:–acid_battery

depending on energy required for your run run time, assuming a 1KWh battery:

lead-acid would weigh approximately between 20 and 30 kilos
lithium ion would weigh between 4 and 10 kilos

as you can see, if the vehicle weights 250 kilos, a 20 kilo difference is not going to make a huge difference with a 400 watt motor for short runs. In any case, you are still running a very low output motor for what is essentially a very heavy load.

If the motor is a given in terms of your limits, you’d be probably better off shaving weight off your frame using aircraft weight saving techniques and reducing passenger weight and use as many bicycle components for your vehicle as possible.

many years ago I was involved in such a vehicle, the inventor made it all from bicycle component parts and it was very light, not much heavier that a battery of the size you would need for a short run (about 50 pounds). 

So we’re back at how long do you need the vehicle to run for between charges and whether you are limited engine wise or not. If endurance and long runs are needed and if you have any slopes you’d need a larger battery and would be much better off with lithium ion… However if cost must be reduced to the maximum, runs are short on flat terrain, unless you are looking for the highest performance, trading battery weight for motor weight, lead acid may well be the more sensible solution.

On June 25, 2015 at 7:26am
Rajesh wrote:

Can anyone tell me how to dispose the waste Lithium after battery assembly?

On August 20, 2015 at 1:28pm
John wrote:

There is an interesting report published today on the UK Air Accident Investigation Board web site on the failure of a lithium battery pack in a Boeing Dreamliner parked at Heathrow Airport. The pack invoved was quite small but caused significant damage to the airframe when it caught fire. Luckily the aircraft was on the round with no one on board.

On October 7, 2015 at 4:25pm
Mason wrote:

Is it safe to mix lithium AA’s with 14500’s to achieve a desired voltage?

On October 8, 2015 at 2:31pm
peter connell wrote:


i am further up the learning curve now and stand by my lifepo4 pouch cell pack idea.

New, They are a no brainer vs 18650 cells. Similar money, way less hassle, very safe ... and the killer factors are… huge discharge rates and all rated storage is usable. 18650s are only 60% usable ideally it seems if you want longevity.

you dont say if its a keeper, for a race?, desired range?

A thought is, you can get 450 watts from lighter 24 or 36v rigs, given the hi discharge rates from lifepo4.

a 20ah pack should yield 60 amps or more.

Standard 3.2v 20ah pouches are .5kg each (so 24v 20ah (8 cells) is 4 kg & 48v is 8kg)

the cells seem to run at ~$15US on alibaba

ditto chris on using bike components as a basis. Maybe there is a way of joining alloy bits using carbon fiber in lieu of welding?

BTW, a bike with a single wheel trailer is a 3 wheeler.

On December 22, 2015 at 4:55am
Ron mackay wrote:

I am buying a travel scoot portable travel scooter powered by a 7.5ah battery. I believe the product comes from Taiwan . Is this safe to take on international flights?

On December 22, 2015 at 7:39am
Charlie S wrote:


You will have a potential problem with tis scooter - because there have been a lot of safety incidents with hover boards this year - hot item but too many fires.  amazon does not sell them anymore.  Just google for facts on incidents.

As I have said before every new application for Lithium-ion batteries result in fires in early commercialization of devices.

Safety statement above needs a re-write or revision.

On January 3, 2016 at 2:34am
Marzan A. wrote:

Hello everyone, needs some help with solving this hoverboard fire puzzle. I am an importer of Hoverboards from selected Chinese manufacturers. Recent “hoverboard catching fire” stories kinda shook me up quite a bit. I import hundreds and thousands of dollars worth of hoverboards. I am trying to figure out if there is anything we can do to solve this problem. I am looking into better battery technology to reduce any such risks and am willing to spend money to find the right technology. Please advice. Also please contact me if you have a solution to this problem.

On January 4, 2016 at 12:09am
Allan wrote:

Dear guys,
Regarding macro telecom BTS sites, it is more suitable to use VRLA batteries.
You can check the long stable and safe performance of it. Now BSB has a new patented solution to prolong lifecycle and monitoring visibility.
If you are interested, pls drop mail to me for further discussion.

On January 4, 2016 at 12:15am
Marzan A. wrote:

Hello any solution to the hoverbard battery fires with lithium ion batteries?

On January 4, 2016 at 1:42am
peter connell wrote:

dunno marzan, you don’t give much detail on the fires, but its no secret li-ion dont like being overcharged, and that’s probably the root of it.

Poor, if any, BMS?

lifepo4 seems very safe chemistry, so spec them for your boards.

Despite the rumours, i dont believe they are heavier or dearer, because they are twice as good in real world ev usage.

On January 4, 2016 at 7:20am
simonj wrote:

Question -

We are currently going to pull some downhole memory gauges, they have a lithium Ion type battery.

We plan to mill out the battery, therefore breaking up the batteries and flowing them back out the wellbore with a fluid.
Does anyone have experience in anthing like lithium put under duress like this?
I am concerned we cause some impact once the cut up pieces of battery re returned to surface.

FYI- the batteries are well spent, having been in the well or 5yrs.

Will we see anything that could cause say a skin burn etc:

On January 4, 2016 at 2:14pm
John Murrell wrote:


I would suggest that yo need to investigate the type of Lithium Battery your memory gauges used. Are they primary non-recharable if so they probably contain lithium metal which reacts with water to create Hydrogen which of course is flamable or explosive when mixed with air. Also the reaction generates heat. The Lithium metal also burns and one burning reacts fairly violently with water. There are some videos on UTube of people dropping burning lithium from a primary cell in water.

On January 6, 2016 at 8:28am
Ryan H wrote:

hoverboards use cheap chinese cells with no protection, also they dont use a BMS at all as i’ve taken a cheap hoverboard apart to investigate..

Corners had been cut in production to try and get them on shelves in time for christmas, and the greedy imbiciles dont care.

I use Li-ion cells on my ebike (48v 20ah 30amp) and hate the scaremongering on this page. you buy cheap, you pay twice (or with your home in flames)

What do you expect when you play with fire (or in this case, electricity)

What truly needs to be done is the price of GOOD cells needs to be reduced so that there is no market for the chinese rip-offs. This is something thats been kept sky high (like super/ultra capacitor prices) because the automotive industry are scared of losing their combustible niche.

To the person back in 2013 whining about the dangers of lithium ion cells because you put 2x 4.2v lithium ion cells in your camera and sons xbox controller…. LOL. you noob…. 1.5 vs 4.2…. very clever…

Do you not think its wise to know some of the facts before you go slamming any old thing in your electronics? just because a plutonium rod may fit inside an AA battery box…. doesnt mean it will actually work or be safe..

On January 24, 2016 at 10:32am
Jay Franke wrote:

Anyone have an idea why a 500A Peak Current Portable Car Jump Starter Power Bank with 12000mAh Capacity (Advanced Safety Protection and Built-In LED Flashlight, 1A & 2A iSmart USB Charging Ports) would fry my cell phone. First time I used this power Bank I charged it as per companies instructions. First time use after full charge was to charge my phone via USB port 2amp output. It immediately burnt my phone at Mini USB input and cracked my screen. USB cable showed burn marks around Mini-port end that plugged into my phone but not at end attached to charger. Seller negates any responsibility for problem and says that the likely cause of the problem is that the phone has foreign matter in the port such as dirt, lint, liquid, etc. While most chargers and phones have a safety mechanism that safeguards against this issue, if the connection is blocked with foreign matter,  there will be internal resistance which prevents power protection mechanism from triggering, which can cause melted phones when a high powered charger like a car jumper kit is connected.

On January 24, 2016 at 12:29pm
John Murrell wrote:

I would check the output voltage on the USB connection to ensure it is within the correct range. You might also try loading it with a resistor to get 1 amp or so but the voltage should be the same or slightly less

On January 24, 2016 at 1:36pm
Jay Franke wrote:

Thanks for your quick response, I am dealing with a chinese supplier that stated
“Based on the findings from the QA lab,  we have ruled out problems in the car charger and charging cable. This leaves the phone. Unfortunately we don’t have the customer’s phone to test, but based on the pictures submitted by the customer submitted, the likely cause of the problem is that the phone has foreign matter in the port such as dirt, lint, liquid, etc. While most chargers and phones have a safety mechanism that safeguards against this issue, if the connection is blocked with foreign matter,  there will be internal resistance which prevents power protection mechanism from triggering, which can cause melted phones when a high powered charger like a car jumper kit is connected.

Unfortunately because our product works as intended, we won’t be able to cover the customer. If the customer still wants the charger back, we can return it to him/her.”

Since I charged my phone almost daily with USB in my car or at home and never had a problem I can not accept their explanation. I wont give them my phone as too much sensitive info is locked in the dead phone and don’t trust anyone that might be able to tap into it. I feel that they are just trying to negate any responsibility and pay for the cost of a new phone—_+/- $200 not a great deal of money but principal is important to me. I sent back the charger and got a refund.

On February 8, 2016 at 7:35am
Dhanya P wrote:

How safe is to use Li-metal batteries with solid electrolytes

On March 3, 2016 at 5:11pm
packbuilder wrote:

Does anyone know how I can go about to get a license to build lithium-ion 12.8v packs!??  Im going to sell these and think having a license might be a good !???

On September 14, 2016 at 11:59am
mar_pan_vas wrote:


Is there any issue / concern when using lithium batteries in extreme conditions? 
Not charging, but operating them, in conditions like:
In the sky at high altitutes ?
in freefall while sky diving - parachuting ?

thinking of the pressure, the altitude, the sudden change in speed / shock when the parachute opens, the high speeds of even 200km/h etc..

any thoughts / suggestions for further research would be appreciated for helping on this research project!

We got them from adafruit , so not ‘no brand’ items, but still thinking if they are suitable for the conditions we will use them..

Great article and useful discussion !


On October 30, 2016 at 3:22pm
Gabriel B wrote:

I have an Ipod 2nd generation and I currently have the battery li-ion battery, but it is protected by an aluminium bag. Is it still safe to open

On November 9, 2016 at 7:59pm
Nick Staveley Stanley MBE wrote:

Since the grounding of the entire fleet of Boeing Dreamliners, “In order to address battery issues” [sic] - I have no confidence in either Li-ion batteries or the technology behind the development of these, potentially, very dangerous bits of kit!
For those who don’t know; Boeing recalled all of their brand-new “Dreamliners” because of overheating, fire and smoke entirely created by the large lithium-ion batteries essential to the operating of the aircraft’s electronic and digital systems.
The creditable action of Boeing was not caused by one single case. There were multiple battery faults/failures and only Boeing know how widespread the faults were! But, if I saw smoke inside an in-flight aircraft cabin - I would instantly think that my life would be over!
At least two flights had been news-reported as having fires in their big li-ion batteries but, on those two flights, both planes were able to land safely because of the quick-thinking of the crew!
I believe that most of the modern passenger-jets main batteries are situated at the front of the aircraft under the port-side crew-cabin floor - in some aircraft this is also very close to the forward passenger toilet-compartments.
Let me say that I don’t believe in mysteries - at the end of the day there is always a solid explanation behind any so-called mystery and, as at this point in time, my theory that both of the missing passenger jets (MH370 and MS804)  could both have been lost as a result of fires originating from the batteries, fits everything we know about these tragedies! Check-out the facts - including the attitudes of both aircraft in their final moments (erratic flight) that could have been caused by heat/fire/explosion burning into control devices - or the crew; switching to manual control and then being overcome by fumes. It all adds up - bot, of course, my theory can only be circumstantial before any direct evidence is discovered.
As for small metal particles being excluded from these batteries, during manufacture, it is not impossible at all - but employing space technology to mass-production batteries would cost a lot more money, slow the process and result in a higher retail cost to the customer = and, as we all sadly know, the majority (in modern society) are willing to accept some collateral damage in favour of low prices. Take, for instance, the Costa Concordia disaster - where the ship’s architects/designers learned absolutely nothing from the sinking of the Titanic! How do huge on-board atria and shopping malls inhibit the ingress of water? How does the omission of sewage back-flow valves fit with the integrity of so-called watertight bulkheads. I think the safety regulators, within both the aviation and maritime industries, need to wake up and carry out much more thorough health & safety assessments!

On January 22, 2017 at 3:39am
Manjeet singh wrote:

I m using lenovo mobile and it is with li-ion battery. My son nailed that battery with pin in 3 areas. Could i use that battery now.

On June 13, 2017 at 12:09pm
Grant wrote:

What is the potential hazard of storing old iPods, Zunes, and other devices that aren’t used anymore?  I have several unused devices just sitting around or in boxes. Could these fail and start a fire without a charge?

On June 14, 2017 at 10:15am
John Murrell wrote:


The safest thing to do is to take the unwanted items to the apropriate recycling center so they cam be disposed of safely.

On August 14, 2017 at 2:54am
Erik wrote:

I have the same concern as Grant. Is it safe to store electronic devices with lithium ion/polymer batteries? I have some old devices I would like to keep around to show in the future to younger generations. Some of today’s classics.

My main concern is storing them. My other concern is plugging them in to power them on after storing them for, say 10 years. At this point the batteries should be depleted and the protection circuits should not allow them to take charge, but these systems can fail.

The safest thing to do would of course be to remove the cells from the device, but that’s unfortunately not possible without causing damage with some products.

On November 22, 2017 at 10:04am
Jamie Fuller wrote:

My kids have been asking for a hoverboard but I’m worried about the batteries in those things. This article - - says UL certification makes them safer is that true?

On January 7, 2018 at 10:46am
Mark Sabelman wrote:

I am planning to use a 12 volt 20 amp deep cycle lithium ion ,made in USA, battery in my station wagon to run a 0.5amp air purifier at night for two hours when I am not in the car. Once a week I would take battery into my basement for a charge. Is this plan safe?

On January 8, 2018 at 1:37pm
John wrote:

I would build a timer and run it off the vehicle battery - 1 AH per night is not going to have much impact on a vehicle battery if it is used frequently.

Biggest risk from li-ion is probably from accidentally short circuiting the battery - make sure you fit a 1 A fuse close to the battery to protect as much of the wiring as possible and secure the battery so it cannot move and damage the wiring

On January 12, 2018 at 9:32pm
thomas wrote:

I have a small hand warmer, made in china, operated by are-chargeable lithium battery.  is it safe near a heart pacemaker ?

On March 7, 2018 at 11:20pm


I am wondering:

1. Is it safe for me to leave lithium-ion batteries charging while I am not at home (fire safety question)?

2. Is it safe for me to leave a lithium-ion powered bluetooth speaker plugged into a USB charger 24/7/365? The speaker has a charger, but I would like to just leave the speaker plugged in and turned on forever (fire safety question).

In closing:

I have a small Chihuahua at home and while I’m away from home I don’t want to return home with my house burned to the ground with my pal burned up inside my home. Is it safe for me to do those two things without being at home?


On March 8, 2018 at 2:47pm
Erik wrote:


1. No batteries should be left unsupervised during charge, and this is especially true for lithium batteries. While they are generally considered safe and issues are rare, thing can go south quickly, and if a thermal runaway happens it’s likely going to vent with flame. I would never leave lithium batteries on charge unsupervised. In fact, I don’t even recommend charging phones/devices while sleeping at night, and I never do it.

2. Same applies as the first question. If it’s correctly designed it should not try to charge it once it has reached full charge, until the charge level drops below a certain level. But unless charging can be disabled I wouldn’t leave it plugged in.

These batteries does not like staying at full charge all the time. Performance will degrade. If you don’t care about using it on battery you could investigate the possibility of removing the battery. This would void any warranty if not considered user removable, and some devices won’t work without a battery present.

On April 24, 2018 at 3:27am
Suryanarayanan wrote:

Can somebody tell if the lithium electrolytes used in Il ion batteries will react & cause Heat, Fire , Damage if in contact with a Silicone ( PolySiloxane ) coating ? Please Let me Know .. Thanks.

On April 24, 2018 at 9:12pm
S.Suryanarayanansur wrote:

Can somebody tell if the lithium electrolytes used in Il ion batteries will react & cause Heat, Fire , Damage if in contact with a Silicone ( PolySiloxane ) coating ? Please Let me Know .. Thanks.

On May 10, 2018 at 7:14am
S Hayward wrote:

what are the consequences of a lithium battery being accidentally crushed in a cardboard compactor. What precautions should be taken if this happens

On May 10, 2018 at 3:10pm
Tami Ware wrote:

I had a lipo battery explode while charging in my garage on 12/31/14.  Water was used to put it out while the door to the house was open allowing smoke and soot into the house.  A restoration company came out the next day but never came to do the work.  My insurance adjuster said they told her everything was a total loss and that I could not list it myself because I was not qualified. 

A year later I was hospitalized for six days with a leg infection and a year after that I was rushed to the ER unable to move my head.  I spent six weeks in the hospital and my diagnosis was a lung abscess and cervical spinal infection. I knew I was really sick for a long time but my doctor was ignoring it even though I could not even walk without holding onto something. 

Now I am wondering if its possible the restoration company did not come back because they did not want to clean the mess up do to its toxicity? 

I wonder if my insurance should have had me move and the fact that they did not could have been illegal do to the health concerns involved? 

I wonder if everything I have that has slowly rusted over time could have been prevented it the restoration company had cleaned it? 

Or if it did not matter that nobody cleaned anything because there was no way to save it and if that’s why they never came back because they knew it would not help? 

If the chemicals may be what’s making my travertine floors to crack and get holes all over them?

On December 20, 2018 at 8:28am
Dylan wrote:

How far back should you stand from one thats going to “explode”?

On January 16, 2019 at 7:47pm
Alan wrote:

Problems with lithum ion batteries are not the technology
Its typical cheep Chinese manufacturing cutting corners , they use very thin paper as a insulator between poles , l(if poles touch BANG!)
Chineese are masters at cutting corners
This is why there materials are forbiden in American aerospace !