Salvage Lithium Ion Batteries From Laptop Batteries

I am always curious to know what is inside any device. Recently I wanted to know about the type of battery inside a laptop’s battery after I have seen a video in YouTube, I believe it’s a video by kipkay about reviving an old laptop’s battery by replacing the lithium ion cells inside.

My good friend’s laptop battery was not working properly it was so bad that if his power cable is disturbed even a little the laptop would turn off immediately. The battery won’t even last for a second. He bought a new one and gave his old one for me so that I can satisfy my curiosity and maybe find some use for it. That was my first battery strip off and I didn’t take pictures of the full procedure and have added whatever I have taken in the last step named First Battery Strip Pictures, however I had another chance to open-up another friend’s laptop battery and have complete pictures of it (this ‘ibles will be showing the second battery strip, so let’s begin…

Obtain the necessary materials and tools to get into the laptop’s battery

Material:

Laptop’s Battery any model will do (the bigger the laptop’s battery the more Li-ion cells in it)

Tools:

Vise – to hold the battery

Rotary tool with mini saw blade attachment/ hacksaw/ plastic cutter (rotary tool is way faster obviously)

Flat screwdriver

Side Cutter

Long Nose/ Needle-nose Plier

Personal Protective Equipment:

Goggles

Disclaimer: Li-ion batteries are dangerous and can catch fire if mishandled properly. Take necessary precautions when dealing with these types of batteries. Also follow safety precautions when using tool both power and hand operated to avoid injuries to yourself or others. I’m not responsible for your safety, be cautious of what you are doing and be safe.

First clamp the battery to a vise or use any tool available at your disposal to hold the battery in a secure position. Do not tighten the vise too much, just tight enough to hold the battery firmly.

I used a small vise, since that is what I have on hand.

I found that it is easier to cut along the line where the two halves of the plastic casing meets.

Ready your rotary tool with a saw blade attachment and cut only the plastic casing do not go deep as you will cut into the cell and it may cause fire (I haven’t cut into a cell yet). Go slowly and you should be fine.

If you are using plastic cutter, you may have to do it multiple times to cut through the plastic. (I have not tried it, however I did tried once with a scoring blade and I couldn’t get through maybe heating the blade and then cutting might have helped but then I got the rotary tool and things become easier).

After cutting along the joint, remove it from the vise and use a flat head screwdriver to pry the case apart. Insert the screwdriver and rotate it to get the plastic open. Be careful not to poke the Li-ion cells.

The cells will be glued to the plastic casing on one side using double sided tape, just pull the other side of the plastic apart and it should come off. Remove the cover and the guts of the laptop battery. You should be seeing Li-ion cells and the control circuit with temperature sensor (not sure of the type let me know if any of you do know).

The cells are connected using metal tabs spot welded to them. I tested the battery voltage (10.23v) and it was close to the voltage of the working battery (10.8v).

First detach the temperature sensor from the cells by simple pulling away at the glued area. It should come off easily.

Note: If you are going to replace the cells and revive/ upgrade the battery make note of the connections made i.e., where the positives and negatives of the cells go and their orientation. I cannot promise that it will work as I am not sure why this battery was not working well. So if you do end up replacing the cells let me know how it went.

Then carefully cut the tabs/ wires that are connected to the circuit and between the cells using a side cutter.

Caution: Do not nick the cells, as it will render the cell useless.

You can leave the metal tabs for ease of soldering, should you require.

However I do not want sharp edges so I decided to remove the tabs.

Use a long nose plier and just roll away the tabs see pictures for more clarity.

From my first battery strip-off, I have salvaged 6 cells of which 2 were dead and one was damaged during extraction. So I ended up having 3 in good condition. 2 temperature sensor and few smd components from the circuit board.

From the second battery strip-off, I have got 3 18650 cells and 2 temperature sensors and few other smd components from the circuit board once I desolder them.

The cells were not depleted completely, they were discharged but where within limits.

Use proper chargers to charge Li-ion cells.

Note: During my first attempt I accidentally nicked a battery while removing the tab from the battery using a wire stripper and it sizzled for couple of seconds with a little smoke. Checking the voltage later shown no degrade, therefore I assumed it is ok. When I used Li-ion Charger to charge this particular battery, it caused the chargers IC to burst and thus ending the chargers life. After which I never charged that particular battery.

Caution: Be careful while charging. Charge at your own risk. Do not charge the cells if it has been damaged. Expensive chargers might have protection to prevent them blowing up. However the cheap ones will just blow off the IC should the cell is damaged. Also watch the polarity when charging.

Currently I am using Nitecore i4 charger to charge the other cells and its been pretty good so far (for a completely dead battery).

I have been using the cells (from my First Battery Strip) to power my XML-U2 flashlight. And have plans to use it to power Arduino and also to make a solar power bank of sorts.

The later 2 are for future ‘ibles.

P.S: I have entered this 'ible in few contests, should it get accepted and if you liked it. Kindly vote so I could win something and make more and share...

This HP battery was my first attempt to open a laptop battery unfortunately I didn't take pictures of all the steps. So I remembered to take pictures of the complete step the next time I open one.