Help! My drill battery won't charge after leaving it in the garage over winter

Hey all, I've got a 20V cordless drill, and after storing it in my unheated garage all winter, the battery won't charge. It's a few years old, but was fine before. I tried a different charger, still no go. Any ideas? Is it dead for good, or can I revive it?

I've seen this a lot. When batteries get cold, especially lithium-ion, they drop below the charger's minimum voltage threshold. Your charger probably thinks it's dead and won't even try. Try warming it up to room temp first, then charge it. If that doesn't work, you might need to jump-start it with a small charge. Look up 'vape battery revival' or something on YouTube, but be careful.

Before doing anything sketchy, check the battery contacts for corrosion or dirt. Clean them with a pencil eraser or contact cleaner. Also, make sure you're using the official charger. And remember, never charge a frozen battery - let it thaw completely. Safety first! If it's still dead, it might be time for a new battery. Some brands have a 3-year warranty.

I had a similar issue with a battery that sat too long. I opened the case, checked the cells with a multimeter, and one was way low. I individually charged it with a bench power supply, but honestly, it's easier to buy a new one. If you're into DIY, you could rebuild it with new cells, but that's a rabbit hole. Let it sit at room temp for 24hrs and try again - worth a shot.

Oh, and if you do try to jump-start it, make sure it's a lithium battery, not NiCad. And use a resistor or something to limit current. I've seen people use a 12V car battery and a bulb to trickle charge. Just don't leave it unattended. But as Paul said, new battery might be the safest bet.