My drill's battery won't charge – any tips?

Hey guys, my old cordless drill’s battery just stopped charging. It’s a 18v NiCd pack. I checked the charger with a multimeter and it outputs voltage, so it’s not the charger. Any cheap fixes? I’d rather not buy a new battery if I can revive this one.

Hey Tim, NiCd batts can develop a 'memory' effect. Try a deep discharge cycle – run the drill till it stops, then charge it full. Sometimes that wakes 'em up. If that fails, you might have a dead cell. You could open the pack and replace individual cells, but that's a pain. Might be cheaper to grab a knockoff battery on Amazon.

Before you go tearing into it, check the contacts on both battery and charger. A little corrosion or dirt can kill the connection. Use a bit of sandpaper or a pencil eraser to clean them. Also, make sure the plastic tabs aren't broken – I've seen that cause poor contact. With NiCd, sometimes a few charge/discharge cycles can recondition them, but if it's not taking any charge, odds are the pack is toast. If you need precision for your projects, I'd just invest in a new lithium-ion set. But you do you.

I had the same thing with my old Dewalt. Tried the deep cycle trick and it worked for a few more months. Also, I've heard of people freezing NiCd batteries overnight to revive them – something about the cold resetting something? Might be a myth, but I tried it and it actually helped for a while. Just bag it up so it doesn't get wet. Worth a shot if you're trying to save a buck!

Thanks everyone. I cleaned the contacts and did a deep discharge – seems to be charging now! We'll see if it holds. Appreciate the tips. If it dies, I'll look into a cheap lithium battery. Cheers!