Do you have Bluetooth headphones that won’t turn on, won’t charge, or the battery drains super fast? In this video I show you exactly how I replace the battery step by step at home using simple tools. The first thing I do is identify which side has the battery—most of the time, the charging port side is the battery side. Then I open the earcup by removing the ear cushions and checking for screws. On my model there were no screws, it was just clipped/locked, so I gently lifted the cover. Inside, you’ll usually find a 3.7V polymer battery connected with red and black wires. In my case the old battery was bulged (puffed up), and that’s a clear sign it’s faulty and can drain instantly. I replace it with a matching battery—same voltage and size (3.7V 300mAh). After desoldering the old battery, I solder red-to-red and black-to-black, then I test charging before reassembling. Once I see the red charging light come on, I insulate the joints, replace the double-sided tape, stick the new battery down, and put everything back together. Finally, I recommend fully charging the new battery before first use.