Reuse Old Laptop Batteries for Prolonged Use of Car Toys (or Any Other Device)

My kids got a new toy for birthday They were very disappointed with the performance of original battery 700mA which i suspect that is much lower. I decided to cheer them up by fixing their toy

I used old HTC charger 1Amp and old USB keyboard. I connected with the improvised connector with Black and Red wire. Since batteries are 4V i use 5 Volt standard charging (for mobile). Its very important to use 1Amp charger not less (since many cheap products mislead costumers).

My fathers laptop battery died. I purchased new one but decided to see what in the old battery. When opened i saw an electronic chips (which probably regulates voltage input and output) with 6 batteries. Batteries where arranged in series of 3 series of 2 parallell batteries. In short every battery has 4 volts x 3 series to make an output of 12v ( or 11.8 ).

In picture you see 2 of 3 batteries pack extracted from the llaptop battery . Other battery is original one (700mA) .

Last and not least.. Laptop battery electronic chip protects battery from overcharging. Be carefull not to charge beyond their voltage. In my case, after disconnecting from charger i check the voltage of batteries with multimeter. If it is around 4.0V its OK.

I tested the car myself for an hour...The results are impresive. Even my kids don't have nerves to discharge the battery.

Lessons learned:

Never throw away llaptop batteries. They are very high quality and can be useful for anything