Does a leaking cell destroy the other cells in the same battery?
You're fine replacing just the bad cell. Clean everything &amp; even sand or file any of the device's contacts that look discolored. If you have another device where the LR44's can go now or in the future write "spare" on them &amp; replace all 3 cells. On the flip side, write the date on just the replacement cell so you don't toss that when the other 2 give out.