Hi joerg_rw!

Thanks for showing interest and for warning. Indeed, You're right about connecting batteries @ different SoC in parallel - just to be sure than no one will try that. Of course I know it, and that limitation is "base" of my project (and reason, why it's developing so slow - I want to be sure that I'm not gonna kill/fry my battery, or bring danger to other people trying my method).

What I'm trying to achieve, is hotswap possibility via special micro-circuit, that will control hotswapping in safe way. It involves cheating chip via BSI (that same battery is still present), then "switching" battery by circuit via electronic - *without* paralleling batteries in reality, yet with so small interval, that N900 won't notice. Of course, no human being can be so fast, thus electronic need to control that I'm designing it in a way that everything can be put inside Mugen Cover, without external things outside N900 needed.

Obviously, inspiration for this project is your thread about hotswaping via killing bme (and I was going to include full info about inspiration, when announcing in Thread). I wanted to introduce more practical way, without need to disable power-hungry applications - transparent hotswap. Also, I'll be very happy to consult everything with community, I'm definitely not gonna publish any unchecked advices, that may put devices/health of other users in danger.

Also, complication of this project is reason, why I dubbed it "mugen-cover-power" - as parody of kernel-power and busybox-power + allusion to internal power source, allowing hotswap. That wasn't just ego thing

Sorry for off-topic here, I just thought that it's worth to clarify.