I thought my mp3 player was dying. After fully charging it, the battery indicator would only fill in 2 of the 4 bars.

It took some searching, but I found one remedy to try before buying a new battery or player. I let the battery drain completely. Even at half capacity, it took around 5 hours to discharge. After it turned itself off from lack of power, I charged it via the USB cable instead of the wall charger. This charges the battery slower and apparently batteries like that.

I’m not sure if this process works with all lithium polymer batteries, but it worked for the one in my Cowon A2. When I started the player up this morning, it had full bars!