Damaged battery wraps dont just look bad, they can be very dangerous.
If your battery wrap is damaged in any way, it wont be doing its job. A battery wrap has a single primary purpose; to provide the maximum possible distance in conductivity between the positive and negative terminal of the cell. If its damaged in any way, you run a serious risk of injury to yourself, your device or your surroundings.
Battery wraps are supplied in pairs.
Why not consider a new case at the same time?