So what do you do with them when they die?
Just throw them in the trash - which harms the environment?
Or just take them to a recycling facility for them to be recycled?
Well, here is the best solution, bring your dead batteries back to life that can save you a chunk of change - By zapping them!
Here is one great instructable, Revive Nicad Batteries by Zapping with a Welder. Of course, you will need a welder, and not many people has one... So I came up with this idea that almost anyone can build!
UPDATED: This instructable has been featured in hackaday!
This instructable involves hacking a device that operates on 300 volts and can be dangerous if not handled correctly. So, I am NOT responsible whatever happens to you using this information.
Step 1: So, Why do Ni-Cad batteries die?
They don't exactly 'die', it is the sulfur crystals that is causing the problem.
The crystals are formed and begin growing caused by:
- Overcharging the cell
- Leaving the cell in the discharge state for a long time
- Memory effect
- Being exposed in high temperature
But, the good thing is the sulfur crystals can be easily destroyed, by putting a hefty surge current through the cell... This vaporize the crystals and the battery should be good as new again!