Recovering a laptop battery (tutorial)

Tutorials for Operating Systems, Applications etc can be posted here.
Post Reply

Did this work for you?

Didnt try and I dont want to try
6
38%
Didnt try but I will try some time soon
4
25%
I tried it but it didnt work
2
13%
I tried it and it worked
4
25%
 
Total votes: 16

Andy
User avatar
Administrator
Posts: 12623
Joined: Fri Aug 18, 2006 11:47 am
Location: United Kingdom
Contact:

Recovering a laptop battery (tutorial)

Post by Andy »

Here is what it looks like (this is the second time im doing it to this battery). Try not to be messy like me!:

Image

And here is the method:

It recovered an 8 year old laptop battery which could power the laptop for 2 minutes, up to an hour. I was astounded as to how much it went up. Im currently doing it to my main laptop to see if works on that too.

The method is as follows:

1. Flatten the battery to its minimum that it will allow in the laptop (until it turns off is preferable)

2. Remove the battery.

3. You will now need a "load" rated around 12-15v to connect directly to the battery. I have used a 12v LED light that I made myself. It draws around 60mA. The lower the current draw the better but the lower it is the longer it will take. 60mA is a bit low but is enough for me.

4. You will now need a multimeter to find out which two of the (usually 6) connections to connect the "load" to.

BE CAREFUL FROM NOW ON. YOU ARE DEALING WITH A LOT OF CURRENT WHICH COULD BE DANGEROUS.

Be sure your multimeter is on DC VOLTS and that the probes are in the correct sockets. It must NOT, I repeat NOT be in the AMPS socket. This will cause a short circuit!


If the connections are in the open, simply put the multimeter on two of the connections and look for a voltage reading. Two of them should give 14-16v (in most laptops its 1-2v more than the stated voltage on the back of the battery).

5. Once you find two connections that give a voltage, you need to figure out which is the positive and which is negative. If the meter reads without a "-" then the connection with the red probe on is the positive, the same for the black negative. If not, then they are the other way round. This is important because the load may not work if its the wrong way round, and it could damage it.

6. Now you know this information, you can connect up your load. Be careful not to let two wires touch that are connecting to the battery. This could cause a short circuit. It could hurt you and/or the battery. The battery could set on fire or explode if this is done.

7. Leave the load on the battery until it no longer works. This is when the batteries internal circuitry has detected that the battery is too low, and continuing drain will damage the lithium cells (does not apply to NI-CAD/NI-MH batteries, simply flatten them till the load doesnt work anymore). It could take more than 6-12 hours depending on the battery. I left mine running overnight, and it was off in the morning.

8. Remove the "load" and put the battery back into the laptop to charge. It should have a noticably increased run time after the recovery operation.

Troubleshooting: If you cannot get the load to work, try looking for two different connections that give a voltage. I came accross two that didnt give much current on the first laptop battery I recovered.

This method works for me. You MUST be careful when doing this because it can be danagerous if you don't know what you are doing. I recommend a basic knowledge in electronics before you do it.

I dont accept any responsibility for damages occuring because of using this tutorial of battery recovery. You follow it at your own risk.


NOTES: This tutorial should work for any kind of Li-Ion battery, including mobile phones etc.

cosmo-freak
User avatar
Donator
Posts: 57
Joined: Sat Sep 30, 2006 11:24 am
Location: Germany
Contact:

Post by cosmo-freak »

I couldn't try it because, you need a notebook battery.
But without a notebook, you don't have a notebook battery ^^

empireum
Donator
Posts: 3557
Joined: Sat Sep 30, 2006 5:00 pm

Post by empireum »

In theory, it should work with all (or a great percentage) of rechargeable batteries that have some kind of complete-drain protection. Usually, you have to avoid completely draining a battery because this will likely damage it. I suspect laptop batteries to be different in that matter.

___
User avatar
Donator
Posts: 1914
Joined: Sat Aug 19, 2006 12:19 am
Location: New Zealand

Post by ___ »

most laptop ones are the lithium ion batteries, which if completey drained the lithium becomes unstable and can catch fire/explode etc..

ppc_digger
Donator
Posts: 590
Joined: Sat Aug 19, 2006 1:25 am
Location: Israel

Post by ppc_digger »

___ wrote:most laptop ones are the lithium ion batteries, which if completey drained the lithium becomes unstable and can catch fire/explode etc..
Like Sony batteries?

Vista Ultimate R2
User avatar
FTP Access
Posts: 2393
Joined: Wed Aug 30, 2006 10:06 pm

Post by Vista Ultimate R2 »

I won't be trying this as I don't like doing stuff that's risky (ie involves electricity!) and don't have the necesary equipment, but thanks for the info anyway as I'm sure there's lots of people here who will want to try this! This works for the older nickel-based batteries as well, does it, or just LiIon ones? Note that "Intelligent Battery" types are much harder to revive though.
Image

Andy
User avatar
Administrator
Posts: 12623
Joined: Fri Aug 18, 2006 11:47 am
Location: United Kingdom
Contact:

Post by Andy »

cosmo-freak wrote:I couldn't try it because, you need a notebook battery.
But without a notebook, you don't have a notebook battery ^^
You should see I wrote:
NOTES: This tutorial should work for any kind of Li-Ion battery, including mobile phones etc.
And yes it does work for any battery, and ALL li-ion batteries by law have to have protection circuitry built in. Ive just done mine again and its recharging fine. The sony ones were badly build which is why they caught fire etc. etc.

This method has worked great for some members of OSBA where I first posted this tutorial, and for those it did work for, they were extreamly pleased with the result.

prx984
User avatar
FTP Access
Posts: 95
Joined: Mon Sep 04, 2006 8:38 pm

Post by prx984 »

This method works great for Ni-Cad batteries. Usually, when a nickel cadmium battery won't take a charge, it has built up a short inside the battery, and by blasting it with high current/voltage, you can burn the short off the battery and recover the power capacity.

I'm going to be rebuilding a laptop battery soon (I think, because this one runs for about 20 minutes, and in that time it drops from 100% to 9% but it will run the computer for hours on end which is weird.)

Andy
User avatar
Administrator
Posts: 12623
Joined: Fri Aug 18, 2006 11:47 am
Location: United Kingdom
Contact:

Post by Andy »

If its a Li-ion battery then the internal battery meter may be uncalibrated. Mine gets like that. The tutorial above should solve that problem. It resets it and then you need to run it for a while on the battery to re-calibrate it.

prx984
User avatar
FTP Access
Posts: 95
Joined: Mon Sep 04, 2006 8:38 pm

Post by prx984 »

I seem to have fixed it. It seems to be dropping the way it should be. So far, about 45 - 60 minutes and its down to 77%. Which is the way the other battery pack is. I'm not going to hold my breath though, because it may drop when it gets lower, and if it does, then it still isn't calibrated correctly.

Andy
User avatar
Administrator
Posts: 12623
Joined: Fri Aug 18, 2006 11:47 am
Location: United Kingdom
Contact:

Post by Andy »

The easiest way to calibrate it again is to take all the alarms off and let it shut itself off, just dont have anything open when you do it. That should do the trick.

Post Reply