I generally replace RTC batteries with the original
Varta 3/V80H as well, but it's a fact they only have a service life of around 6 years max. After that, they can start leaking at any time. So as long as you replace the battery every 6 years, it's good enough.
When I'm doing battery replacements in customer's machines, I have a pre-printed label to stick on the back showing the battery replacement date and the replace by date.
@Amiduffer
I might look at setting up a "do-it-yourself kit" of some sort then over the next few weeks/months as well as writing an application note/tech article for my webserver.
It's nearly summer here in NZ which means the end of yet another snowboarding season :-( On the plus side, I can actually get some work done now, so will see if I can fit it in with my other summer projects.
Send me an email so I have your contact details. I can probably do something cheap as a product trial in exchange for some feedback email, etc.