3 ms·

I’d never have thought of remote mounted CMOS battery

• toast0 4y ago
  CMOS batteries are commonly lithium cells which usually work for 7-10 years. It's almost certainly going to fail electrically in a 20 year system, even if it's power continuously (but there's likely to be blips here and there), but the seal may or may not fail too. I've seen a couple crusty coin cells; it's not super common, but it can happen, and battery leakage is not kind to circuit boards.