The new 6-cell laptop batteries die after around 600-800 charging cycles, after which you have to spend around € 60 to order a replacement. It is a nice cost, and if these batteries are not disposed of correctly they can also pollute the environment.
Steps
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Step 1. Disconnect the battery from the laptop
There should be two tabs: slide them to unlock them, then slide the battery out.
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Step 2. Open the battery
To do this you will need to arm yourself with a lot of patience and a flat screwdriver or butter knife.
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Step 3. You will see 6-8 cells connected to the circuit board
This is the battery control unit. Look near the connector to find the board and trace the cables. Carefully examine each cell with a multimeter to make sure each is completely discharged.
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Step 4. Write down the wiring diagram
This is a very important step.
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Step 5. Use a pointed electric soldering iron to separate the cells from the wires
Take them out of the case.
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Step 6. Now weld the new cells together using the connection diagram you noted in step 4
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Step 7. Slip the new cells into the case
Solder the cells and cables.
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Step 8. Put both rows of cells back together
Let it rest for about 48 hours.
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Step 9. Your hack is complete
Insert the battery and start charging. Turn on your computer and you're done!
Advice
- Cells can explode if soldered directly to other cells, so it's best to ask the seller if they can add solder tabs specifically for you.
- Buy new rechargeable cells; eBay is a good place to look for them.
- In general, a dead battery cannot provide even a minimum of power. Most apparently bad batteries are nothing more than uncalibrated batteries, and you just need to calibrate them to get them back in good condition.
Warnings
- Warning: Some battery packs have strange shapes, such as the Thinkpad T61 and Inspiron 6400 batteries.
- Always pay close attention. The cells can explode if they get too hot during welding or if they take hits.
- If you are not an expert in this kind of work, the best choice for you is to buy a new battery.