Help! My cordless chainsaw battery won't charge - flashing red light

Hey folks, having a weird issue with my 18V brushless chainsaw. The battery won't charge - charger shows a flashing red light. Saw was working fine yesterday, cut up some fallen branches. Battery is about 2 years old. Tried cleaning the contacts with isopropyl alcohol, no change. Anyone seen this before? Model is PowerCut Pro 18V.

Dave, first thing I'd check - is it just one battery or multiple? If it's just that battery, it might be toast. Lithium batteries degrade over time, especially if left discharged. Try a different battery if you have one. Also, make sure the charger isn't overheating - feel the vents after 10 minutes. I've revived a few by doing a 'jump start' with another battery, but that's risky if you're not experienced.

omg i had this EXACT thing happen with my trimmer last month! The red blinking light means the battery protection circuit tripped. My dad (who's an electrician) said sometimes they get stuck in safety mode. Try leaving it on the charger for like 2 hours even with the light blinking. Mine eventually went green! Also check if the battery feels swollen at all?

Interesting issue. The PowerCut Pro 18V uses the same battery platform as their older drill series. I have six of those batteries in my collection. The flashing red usually indicates either: 1) Temperature fault (too hot/cold), 2) Voltage too low, or 3) Internal fault. Let it sit at room temp for 4 hours, then try charging. If no luck, contact manufacturer - some have 3-year battery warranties. I'd avoid makeshift fixes that could damage the BMS.

Thanks everyone! Update: Tried Will's suggestion - my other battery charges fine, so it's just this one. Pete, left it charging for 3 hours, still blinking. Chris, battery isn't swollen and was stored in my garage (about 65°F). Guess it's just dead after 2 years? Kinda disappointing since I only used it maybe 20 times total. Might just buy a new one unless anyone knows a reset trick?