Cordless Screwdriver Battery Won't Charge - Any Fix?

Hey everyone, my 18V cordless screwdriver just stopped charging. The charger light stays green even when the battery is dead. I've tried reseating it, cleaning contacts, but nothing. Battery is about 2 years old. Any ideas? Is it toast?

I've seen that before. Sometimes it's the battery's internal cells going bad, but also check the charger's output with a multimeter. If it's fine, you might have a dead cell or a broken solder joint on the battery's circuit board. If you're handy, you could crack it open and look for swollen cells or bad connections. But honestly, with 2 years of use, a new battery might be cheaper than the hassle. I've revived a few by re-soldering, but it's not always worth it.

Before you give up, make sure you're using the correct charger for that battery. Some people mix chargers and the electronics won't charge if there's a mismatch. Also, check if the battery has any 'fuel gauge' - if it shows one bar, it might be in a deep discharge. Try leaving it on charge for up to 24 hours - sometimes it takes a while to wake up. If that fails, it's likely the battery has a faulty cell. You can test each cell with a multimeter - they should be around 1.2V each for NiCd or 3.6V for Li-ion. If any are below spec, that bank is dead. Replacement batteries for that model should be around $40-50 online. I'd say just get a new one unless you enjoy soldering and have a spot welder for Li-ion.

Thanks for the replies! I checked the charger with a multimeter, and it's outputting the right voltage. I also tried charging for 24 hours, still no go. Let me open the battery and see if anything looks obvious. If not, I'll just order a new one. Appreciate the help!

No problem! If you open it and see any swollen or leaking cells, that's a definite sign. Just be careful with lithium-ion cells - they can be dangerous if punctured. Maybe post a pic? We could tell you if it's saveable.