I Upgraded my A310 with an A5000 motherboard. Unfortunately, the CMOS battery shorted as it touched the disk bridge. At first, I didn't notice this and thought the battery was bad, so I cut off the battery and soldered leads to the A310 CMOS batteries at the left side of the case. This worked perfectly.
Later, I discovered the real reason for the failure of the original battery and reinserted it (wrapped in tape to avoid shorting). So, in conclusion, you don't have to use original batteries.