Does anyone know how cheaper rc chargers balance cells?

I just found a cell laying around on the top of a shelf, it’s been there for about 1 year and a half, the wrapping(grey plastic) that seems to go around the cell is loose, it’s no longer sticking to the inside of the cell. The voltage is still 3.246V. I also find that it’s a lot more flexible then a normal cell. Anyone saw this before?