All right then.
Thanks a lot for your helps. I followed one of the suggestions, to google
for a how to or something. Google, with some little work, actually did its
job, and got me this:
http://www.batteryuniversity.com/parttwo-34.htm
Apparently, to make a lithium ions battery live longer, one should
actually not discharge it all all the time, and do that only once in about
30 cycles to cancel memory effects. Also, they suggest to extract it, when
on AC power (the shop guy wasn't completely wrong after all), although
that may give some problems.
If some of you know anything more than me about hardware, or chemistry
stuff, have a go at reading it, and maybe share your knowledge with the
rest of us, who PC like a little part of our brain and a better interface
between what we plan and what we actually do, and don't know anything
about how they actually work. Well, this applies to me at least.
Cheers
Ale
PS:IF anybody run into different information, please let me know!