> That method of charging is OK, will not give you the longest service
> life. It will dry out batteries.

Ah, that I didn't know

> If you put some hysteresis in there so it stops when it hits 14.x and
> then resumes charging again at 13.x you will get twice as much life
> out of the battery

It's likely that the voltage will fall lower than that. I intend to instruct
the user very clearly put it on charge after use but mains will not be
necessarily be available to pick up charging at any particular voltage.
Ideally, if instructions are followed, the battery should be in reasonable
charge during use

> It's pretty easy to achieve, you can use an LM317, three transistors,
> a rectifier-type diode and a few resistors.

> I can sketch you something when I have time, but you probably see
> what I'm describing

Yes, I can, kind of. Not quite clear on the LM317 input arrangement
so a diagram would be helpful. As the unit has an LCD it would be
good to include it and the PIC in the charge process. That would give
the user some feedback about what's happening and also re-inforce
the necessity for regular charging

I'd be quite happy to write up the whole thing as a piclist project page

wbr, Joe 

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