BU-706: Summary of Do’s and Don’ts

Table 1 provides suggestions on how to extend battery life by following simple guidelines. Because of similarities within systems, the chemistries are limited to lead, nickel and lithium.

Table 1: Dos and don’ts summary how to use, maintain and dispose of batteries.

Battery care

Lead acid: Flooded, sealed, AGM

Nickel-based:
NiCd, NiMH

Lithium-ion: Cobalt, manganese, phosphate

Best way
to charge

Apply a saturated charge to prevent sulfation; can stay on charge with correct float charge.

Avoid getting battery too hot on charge. Do not leave battery in charger for more than a few days (memory!).

Partial and random charge is fine; does not need full charge; lower voltage limit preferred; keep battery cool.

Charge methods

 

Constant voltage to 2.40–2.45/cell, float
at 2.25–2.30V/cell; battery stays cool; no fast charge possible.
Charge  = 14h

Constant current, trickle charge at 0.05C, fast charge preferred.
Slow charge  = 14h
Rapid charge = 3h
Fast charge   = 1h

Constant voltage to 4.20V/cell; no trickle charge; battery can
stay in charger
Rapid charge = 3h
Fast charge = 1h

Discharge

 

Do not cycle starter batteries; avoid full discharges; always charge after use.

Do not over-discharge under heavy load; cell reversal causes short. Avoid full discharges.

Prevent full cycles, apply some charge after a full discharge to keep the protection circuit alive.

How to prolong battery

Limit deep cycling, apply topping charge every 6 months while in storage to prevent sulfation, keep cells at or above 2.10V

Do not keep battery in charger for more than a few days, discharge to 1V/cell every 1–3 months to prevent memory (NiCd)

Keep cool, battery lasts longest when operating in mid state-of-charge of 20–80%. Prevent ultra-fast charging and high loads.

Storage

 

Do not store below 2.10V/cell; keep fully charged if possible

Store in cool place; NiCd stores for 5 years; prime before use

Store at 40% charge in cool place (40% SoC reads 3.75–3.80V/cell)

Disposal

Do not dispose. Lead is a toxic metal

NiCd: Do not dispose.
NiMH: Can be disposed in low volume

Can be disposed of in low volume


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 












 

Comments

On November 9, 2010 at 10:10pm
Erick wrote:

I still have a doubt here, It’s safety or not to the battery if I remove it from the laptop while it’s running? Or I need to turn off the laptop in order to remove the battery?
Thanks!

On December 4, 2010 at 11:30am
Jeff wrote:

It is generally safer to remove and replace the battery when the computer is turned off, but as long as the computer is plugged in there should be no major problems.

On December 19, 2010 at 7:06am
moza ahmed wrote:

me 2 .. i still remove the battery while laptop is running .

& i think that is good way ,, isn’t it ?

 

On January 3, 2011 at 5:27pm
Enrique wrote:

What does 80% depth of charge mean? Should I charge until 80% then use, or should I charge to 100% and then use until 80% then recharge?

On January 6, 2011 at 5:12am
Boris wrote:

That’s “80% depth-of-discharge”, DIScharge, not charge. Thank you,

On January 14, 2011 at 12:46am
Michał Surowiecki wrote:

Thanks, these are helpful information:) But what about Li-Polymer batteries, how to charge them?

On January 14, 2011 at 8:56am
Cadex Electronics Inc. wrote:

@Michal - LiPo charging rules follow the Li-ion column.

On January 20, 2011 at 4:32am
nitin wrote:

should we use laptops with only charged battery power or run laptops with direct powers along with batteries to ensure more life for batteries.

On January 21, 2011 at 6:13am
Riezknoe wrote:

Thanks….btw does using the battery while charging ‘drain’ the battery????
eg.talking on mobile phone while charging….

On January 21, 2011 at 9:51am
Boris wrote:

Sometimes battery-powered devices use battery power even they are charging, so they “drain” batteries when charging.
Some don’t, they use external power source such as power from the charger, then these kinda devices don’t “drain” batteries when charging.

On January 21, 2011 at 9:54am
Boris wrote:

“Sometimes battery-powered devices use battery power “
I mean devices that always powered by battery power when charging.

On January 24, 2011 at 9:01am
Riezknoe wrote:

oow…..thanx…

On February 7, 2011 at 7:40pm
Craig wrote:

Is it OK to recharge a Li-ion battery immediately after use?  While it’s still warm?  I remember that was the case with NiCd batteries when racing RC cars.

On February 10, 2011 at 10:48pm
Boris wrote:

Craig, if you do not need to use the device immediately, it would be very kind of you to let it cool down before charging.
While charging any kond of batteries, it will warm up or heat up, so you guys need to do something to cool them down.

On February 10, 2011 at 11:01pm
Boris wrote:

nitin, there are a few circumstances:
If the AC incoming power are stable where you work at with the laptop, you can discharge your battery to 30~40% power left by using the power of the batt., then put the batt. away your laptop to storage them;
If the AC incoming power are quite not stable, or there’s a scheduled power off where you work at, you’d better keep them in the laptop. That’s because you may / will need them any minute.

On March 11, 2011 at 9:11pm
samir wrote:

how much battery charge level should be left off in battery when not using laptop battery for 1 or 2 weeks or i mean instead of using battery i use external power. will this help in maintain long life of a laptop battery? i mean to say put battery into laptop when u away from power source.

plz tell if using laptop without battery affect’s its performance?
is it the good practice?

also please tell is it good to perform full recharge cycle in cell phone batteries with 1500 mah capacities or lower???
how often should we charge cell phone batteries for their long life and performance?

On April 19, 2011 at 12:34pm
fhhuber wrote:

Regarding partial charging a Li based battery:

In Radio Control applications the “LVC” (low voltage cutoff) is often based on the voltage of the pack when it is plugged in.  Thus a partially charged pack can result in excessively low cut-off which will damage the battery.  Always fully charge a battery used to power a radio controlled model.

Also note that LiPo is easier to damage through improper charging or over-discharging than Lion or LiFe/LiFePO4.  Thus this page needs updating and separate columns for the different types of Lithium based cells… or a separate page just for Li based cells.

On April 19, 2011 at 3:04pm
Rob wrote:

My laptop has an option to turn off the battery charger while remaining plugged in (and operating).

While I understand removing the battery is the best way to prolong life, I prefer to keep my battery in the laptop so I don’t lose work in case of a power glitch or failure. Each time I start my computer, it reminds me my battery is not being charged and tells me how much charge is left. In two weeks, it has already dropped to 88% charge and my computer is brand new.

My question is, if I want to prolong the batteries life, at what charge level should I turn the charger back on? How long would you expect it to take to reach that charge level?

On May 17, 2011 at 2:09pm
Christine wrote:

Does brand matter in terms of battery/charger interaction?
I need to buy a charger for a CRV3 battery, and I was wondering if there is a problem charging generic batteries with a Kodak charger and vice versa.

On May 20, 2011 at 3:43pm
Tommy wrote:

is it okay to use laptop directly from AC power? is there any downside other than there’s a scheduled power off

is it right that removing the battery is the best way to prolong life??

On June 3, 2011 at 10:39pm
Angel wrote:

“apply some charge after a full discharge”
so what should I do? discharge until 20%, then plug in the A/C immediately and countinue using, or shut down, let it cool, then charge?

On July 13, 2011 at 2:43pm
Egberth wrote:

i like that web ,it has been answered my question thanks a lot

On July 21, 2011 at 8:40am
Glorianne wrote:

I have one question which I would like some assistance on:

My camera uses a battrey NB-4L, 3.7V, 760mAh(Li-on). Now I would like to replace the battrey as the lifetime of the battrey has become too short.

Would a battrey with a higher capacity [NB 4L, 3.7V 900mAh (lion)] be used on the camera or will it damage the camera (if it works at all cause I have no idea).  I would appreciate if someone could kindly advice on this. Thanks in advance!

On August 13, 2011 at 6:05pm
Lynn wrote:

I have the same question as Glorianne too.
My camera uses the battery NB-4L, 3.7V, 760mAh(Li-on). If I use a higher capacity battery, NB 4L, 3.7V 900mAh (lion)] - will it damage the camera?

Thanks.

On September 16, 2011 at 2:49am
Randi James wrote:

I have few quetions on charging cell phone batteries.  Is it gppd tp keep unplugging and plugging back in the phone while it is being charged? (like to move it to different spot) or should you plug it in and leave it untill it is fully charged. 

Is it good for the battery to just charge it for few minutes at a time, just enough to last short bit.  (battery is low so charge for 30 min to get some charge on it, then keep doing that over and over.)

On September 19, 2011 at 1:34am
Boris wrote:

To Randi James

Sometimes battery-powered devices use battery power even they are charging, so they “drain” batteries when charging.
Some don’t, they use external power source such as power from the charger, then these kinda devices don’t “drain” batteries when charging.

“Sometimes battery-powered devices use battery power “
I mean devices that always powered by battery power when charging.

On October 26, 2011 at 10:21pm
Lola wrote:

Hi, just got a new camera with li-ion battery and was wondering if i should charge it before i use it (and if so, then for how long) even though it says it’s fully charged? I remember having to charge cell phone batteries for many numbers of hours before use in the past.

On October 28, 2011 at 9:54pm
Boris wrote:

To Lola:
The Li-ion battery?If the power is not full, just charge it. When it’s full, ordinarily it would stop charging. See the table atop for deails.

On October 30, 2011 at 10:36pm
Vanessa wrote:

I read somewhere if I have a chance to charge the Li-Ion battery, I should just do it. So for those batteries basically always leave them on the charger?

So, I have a Dell laptop with Li-Ion that I got last year. I have a 6 cell and 9 cell battery. Should I keep my battery constantly charging or should I go to 100% and unplug it and then charge it again when it says battery is low or maybe half way?
Is it the same for my Droid 3 phone Li-ion battery? I charge it every night and it doesn’t get below 50%, 40% or 30% rarely.

On November 12, 2011 at 5:48am
Charles Fisher-Post wrote:

My UL V-2833 Class 2 Battery Charger does not work (or, at least the charging lights don’t turn on), and I never even used it once! I put the batteries in the unit in pairs, like the instructions say.

However, when I traveled with it, I stored the batteries in the unit itself, unplugged of course. My question is—can storing rechargable batteries in the unplugged recharging unit cause it to break? That’s the only explanation I can summon, other than faulty mechanics.

On November 15, 2011 at 6:49am
prince wrote:

I use acer inspire 5516…my uncle gave it 2 me.
The battery take an hour to get fuly chargd(dn’t knw if its geting weak). wen its ful i stil leave it on AC til i’m tru.
Wen i unplug it, i use d main battry to 20%.
Is it advicable?

On November 18, 2011 at 4:32pm
omed wrote:

i bought laptop hp dv5 before 3 years ago ,so right now during using the lap top an alarm comeing talking about that my battrery should be replacement ,and befor i were recharging in when it need that ,otherwise i were used it without pluging.so could you guide me to the right way.

thanks

On November 20, 2011 at 6:27am
Ryan wrote:

I bought 2900mAh AA batteries and a 200mA charger. After 8 hours the led’s on the charger go off and it switches to a trickle charge. When I do the math it says they need to charge for 17 hours. Do I reset the charger to charge through another 8 hour cycle or do I let it continue on the trickle charge for the remaining time?

Thanks

On December 9, 2011 at 1:36pm
Guillaume wrote:

Can anyone answer my question ? I am wondering how the temperature is affecting the internal resistance of the battery. I know that a lower temperature will raise the internal resistance and vice versa.

My question is more the “by how much” part. For instance, at 25°C, the internal resistance of my lead acid 12V 16AH battery is 4mH. What will be the internal resistance of that battery at -40°C ?

Pretty sure it depends on the battery’s manufacturer but is there any way to estimate this value other then testing at -40°C ?

On January 3, 2012 at 12:09pm
ali najafi wrote:

i still can’t find out how to charge my lithium battery for the first time?some of my friend told me to charge it 12 hours and some others say just charge it for 3 hours?how could i know what’s best for the first time?

On January 9, 2012 at 6:17am
j.sri lakshmi wrote:

is it possible to charge a battery using micro wave?

On February 5, 2012 at 7:51pm
roger samala wrote:

we ordered Stationary Industrial Single cell Vented Type Lead Acid (VTLA) batteries 900 AH. Since the standard procedure in shipping VTLA is in dry charged condition and when we received the shipment it is already filled-up with electrolyte solution from the factory (France) and delivered here in Philippines. Upon inspection of the batteries we found formation of white powder at the bottom of the plastic casing. Does this indicate that the batteries are old stock?....have been in stock with electrolyte for months… we are using 48VDC for our Repeater sites and this is the first delivery (replacement of of our old batteries) consisting of 96 sites. Question >>> Do we have to accept or reject said said shipment ?

On February 17, 2012 at 9:54pm
rajvi wrote:

Why mobile battery is of rating 3.7 v?

On February 22, 2012 at 6:06am
aj wrote:

is it uk if you used your netbook full without unplugging then used it? ahm,. i unplugged it after using.

On February 22, 2012 at 6:08am
aj wrote:

di kaya maless ang capacity of that?? while using it then it is fully chareg??

On February 23, 2012 at 3:09am
jollyoger wrote:

VTLA or Vented Type Lead Acid battery should be delivered DRY CHARGE. Since you will transport it to other place I think you need to get clearance to concerned environmental agencies of the countries where it will be delivered. It is the standard procedure to make sure that the batteries are brand new and not second hand. There will be no basis for the end user to know that the batteries have been stored for a long time.

On February 24, 2012 at 7:34am
teresa boling wrote:

Can you tell me what kind of battert is in a lap top.Lead acid,Nickel based or Lithium?  its a new hp. thanks teresa

On March 1, 2012 at 7:29am
John Paul C. wrote:

There are some questions here that were not being answered. The msot common question is “Is it OK to use the charger while still the battery is connected and being USED”?. Well, for me, just a piece of an advice, let the notebook charge battery while you are using it, even if it is fully charged. That is if the battery is Li-Ion. That’s one of the features Li-Ion has compare to those NimH or NicAD. That is how I prolonged my battery from my Toshiba for almost 3 years now, going 4 years.

On May 13, 2012 at 7:48pm
Adrian wrote:

Don’t ever use direct power to your laptop if your battery removed from laptop. If the house electricity sudden off, it will give damage to laptop motherboard. My last laptop is useless now because the motherboard is not functional now. It was because i only use direct power, and when the electricity suddenly shut down, it also shut my laptop. then when i open it back, the motherboard crash.

On June 22, 2012 at 11:22pm
ishmAEL JAFI wrote:

is it ok to charge phone battery using the universal charger, the one that charges the battery out of the phone? And can i connect a charger direct to the back of my phone if my phone no longer charges thru the port? Thanx gguys

On June 27, 2012 at 5:22am
Florence wrote:

What’s the danger of leaving my camera still charging if it’s already fully charged.
PS:It still works but I cannot upload photos to my laptop anymore :/
Please help me!

On June 30, 2012 at 11:09pm
SAURABH AWASTHI wrote:

If someone overfilled the sealed Ni-Cd batteries,what are the danger may be there?

On July 4, 2012 at 11:58pm
jaiprakash wrote:

after given freshening charge of Ni-Cd battery always taken 10 amp current why???

On July 15, 2012 at 9:18pm
narbada singh wrote:

sir,
please explain me weather i should keep charging my laptop while using it or remove it once it is charged

On July 18, 2012 at 9:29am
Eswar wrote:

Sir, Can I always Use my Laptop on AC power, after removing my Exhausted Battery? Will it make any harm to my Laptop? Pls advise

On August 16, 2012 at 7:52pm
Haz wrote:

Hi my laptop charger was damaged about two weeks ago and the charge on my laptop was completely gone I finanly found the same charger it’s been nearly 12 hours since iv been charging my laptop and it still does not turn on how long would I have to charge it my laptop has been dead for about two weeks now. Thanks

On September 1, 2012 at 9:32am
Muhammad zeeshan wrote:

I want to charge a battery which is being used by a DC motor at the same time
What should be my precautions?
And will the polarity of the mOtor be reverse too in case of charging?
At what voltage should i charge the battery of 12 volts
If its a normal acid water battery?

On September 10, 2012 at 7:32am
BR wrote:

Is it safe to charge a smartphone while it is in an Otterbox case?  I have heard that will cause excessive heat which will damage the battery or shorten its lifespan?

Thanks for your help..

On September 27, 2012 at 10:08pm
murray c wrote:

The following advice is in a portable radio users manual. The batteries are Ni Mh which do not have memory effect so why discharge to condition and does constant trickle charge age battery?

• Leaving the battery on charge
You can leave a battery/radio in the charger once charging is
complete. Leaving a battery in the charger will not
overcharge or damage it.
You can remove a battery/radio from the charger at any time
without harming the battery, the radio, or the charger.
When you return the battery/radio to the charger, charging
is automatically resumed.
• Conditioning NiMH batteries
‘Condition’ a NiMH battery every three months to extend its
shift life. Conditioning enables a battery to hold its charge
for longer.
To condition a NiMH battery:
■ Leave the radio switched on and ignore the ‘low battery’
warnings from the radio.
When the radio switches itself off, the battery is fully
discharged and ready to be recharged.

On October 31, 2012 at 6:51am
Amzi Java wrote:

in the beginning of this year, my laptop battery used to stay for up to 2 hrs. now, in Oct, it barely lasts up to 55mins. please, give me some practical tips on the use of batteries, especially for laptops and torchlights, to ensure their long life.

On February 23, 2013 at 2:50am
raj wrote:

should the charger be connected even if battery is fully charged?

On February 26, 2013 at 7:15am
Carlos Paixao wrote:

I find it article very awesome, but Its kinda confusing to me.

The other article was saying that we might avoid keep batteries on cradle charging when it gets full charged for keeping it away from parasite cycles or mini cycles.

But here you said for li-io “battery can
stay in charger”.

So what is the real, I can keep it on dock or travel charger while using it or no?

Consider LI-IO and LI-PO battery for this.

On April 15, 2013 at 12:06pm
Sara wrote:

Is it bad if I keep my Mac laptop always charged? (Like it’s always connected to its charger) Does it drain from the main battery life after awhile or would you just use the electricity coming from the charger?

On April 16, 2013 at 3:18am
Zeeshan wrote:

No its aafe to keep ur mac book charged
All laptops have an internal tripper that will turn off caharging to the battery automatically when full

And yes when the charger is connected the battery wil not drain
It will use power from charger

On May 8, 2013 at 4:25am
windie wrote:

hello, just wanna ask, I have just bought new mobile phone with new battery, and after a week, I couldn’t charge it to full (100%), it would start charging slowly after 90%, not even 1% per hour, is it normal? or should I get new batteries?

I did read that for Li-ion battery it would be best to not charge fully, simply wonder if my battery is broken or something

On October 9, 2013 at 2:49am
Jhonsone wrote:

I’ve a buildin battery notebook can I leave it pluggin when using?

On December 15, 2013 at 11:41pm
Renjith wrote:

is it advisable to charge the battery of android mobiles using data cable connecting to a laptop or PC without directly connecting to AC power supply.

On December 16, 2013 at 6:03am
Zeeshan wrote:

Renjith
It really doesnt matter
Becoz if u read the instuctions from ur ac charger
U will see that both ac charge abd the usb port of ur pc gives out 5V dc
It is advisable to use ur pc usb port as a charger if u have fluctuating AC supply at ur home

On March 2, 2014 at 2:14pm
Steven wrote:

So I have started making pouch cell batteries and am having issues charging them. I put the electrolyte in (glove box) and then do the final seal. I connect it to a battery analyzer and set it to cycle (formation?). But it only gain capacity on constant voltage charging, and when it’s on either constant current charge/discharge, it immediately stops and goes to the next step. What could be going wrong?

Thanks!

On April 19, 2014 at 9:36pm
352 wrote:

What quantity of water is damaged if I dispose a battery there?

On April 20, 2014 at 1:14am
Zeeshan wrote:

If u disposed a battery in water then the ph of water goes towards 0 but the solution is very dilute so in short no much harm done

On June 20, 2014 at 12:19pm
Cornelius wrote:

Is it good to play games or use the laptop while charging the battery ....plz help me ....!!!!

On June 25, 2014 at 11:28am
dosmastr wrote:

NI-CAD
avoid full discharges?

If you only kill it 50%, then charge it, thats how you end up with memory.

I have always been told run a nicad until its DEAD DEAD DEAD otherwise you will develop a memory

On August 23, 2014 at 3:19am
James Rv. wrote:

Is it trure that charging your cell phone while making a call could cause your device to explode?

On September 2, 2014 at 10:30pm
Riad Moucarry wrote:

Hello,

I have a car battery for home use, 12V 55 Ah, attached to it are LED for room lighting and a ADSL router to access the internet.

My question, can I keep the charger always attached to the battery in order to charge it whenever the 220V is available OR that is not good for the battery?

Best regards.

On September 3, 2014 at 4:59am
Zeeshan wrote:

Yes u an leave the charging on if the battery is not dry battery and the charger isnt available all the time but i recommend u buy a 12 v over charge protection kit or u can make it urself
Its really easy and cheap to buy or build
Buy a trickle charger if u do so

On September 9, 2014 at 11:28pm
Raghu wrote:

Hi,

The discussion here was very useful as I got new laptpo which has Lithium Ion Battery. I have gone through all the comments while I got most of the answer but I did not find the exact answer to suit my needs, here is my concern can you please let me know how to handle this situation?

I work on Laptop most of the times from Home, there isn’t power issue however the power oges off all the sudden without any notice as there are unschedule power cuts. Now as I use laptop most of the times it is ok to keep the AC Power plugged in whlile Battery inside? If yes then shoudl I keep discharging Battery manually by switching off power? Please let me know how to handle this situation?

1) Keep working with AC Power on for continously for a month and then discrhage the battery fully and then continue or
2) Keep working with AC Power and keep discharging the batter partially everyday? and then again continue AC power?

Just guide me on this, this would be a very valuable help for me.

On September 10, 2014 at 8:09am
Zeeshan wrote:

U cab keep the ac charging on at all times when available. Ur laptop battery will however go down after 3 years…. No worries
Just avoid fast discharge/drainage of battery

On September 10, 2014 at 8:16am
Raghu wrote:

Thanks,

So you mean no need to keep the battery discharge at frequent intervals? So you mean even if we try to discharge it regularly the Batterly life lasts for only 3 years?

Also, just confused with your comment “Just avoid fast discharge/drainage of battery”, do you mean I should not discharge it completely?

On September 10, 2014 at 10:00am
Zeeshan wrote:

i meant that you can keep the charging of the laptop ON whenever u have AC supply at ease


these lithium ion batteries have charging cycles which best work when the battery is charged slowly, charged above 90%, used till below 20% (or even 10%)...never fully discharge the battery

what i meant with fast discharge was that when the charger is not available dont play heavy games or run heavy softwares that drain the battery very fast


in short, fast charging and fast discharging is harmful for battery
and these laptop batteries will last upto 3 years atmost with full care

On September 10, 2014 at 11:20pm
Raghu wrote:

Thanks for your help, it was really helpful for me to have my new Laptop Battery understand and how to maintain.

On October 27, 2014 at 1:22am
ronil wrote:

Need an advice. I am using my android phone 3.5 hrs straight game leaving 15%-20% juice. after that i charged it to 100% always. Then after fully charged, rest for 10 mins and then play again straight 3.5hrs. In other words, i am charging my phone twice a day. is that okay?  Thanks in advance.

On October 27, 2014 at 5:51am
Zeeshan wrote:

Well it is harmful for ur fone battery (this fast charging and fast discharging) because ur battery has a limited number of cycles and according to u that u are using 2 cycles per day
However its not that big of a deal coz phone batteries are cheap
Ur welcome