Discharge of external battery pack

[marketheredge]

This week, I purchased a CF/battery sleeve for my 3850 and a CF WiFi card for browsing the internet at home, which I've enjoyed immensely the past couple of days.

So my question. It seems each day's activity will pretty much drain the external sleeve battery almost completely, and maybe use just a little juice from the built-in battery. I pop it in my cradle at work the next morning and recharge.

Towards the end of the night, I'll get the incessant reminder about the external battery being near death, and suggesting I turn it off lest I lose data, etc.

Is it okay to just keep going until the external battery is completely drained, knowing, of course, that I still have the internal battery (which is what I do)? I mean, is there anything else I should do to help extend the life of the external battery, or should I just be content with the fact that when it does wear out, it can be replaced?

Thanks for any advice.

[Jason Dunn]

I seem to remember hearing something about the Expansion Plus sleeves being unable to power a CF or PCMCIA card once the battery was drained - it wouldn't switch over to using the main battery. I don't know if this was ever fixed, but it would seem to be a frustrating limitation...

[marketheredge]

Actually that's not the case, I can even completely remove the external battery and still use the compact flash card (at least with my 256 storage card and my WiFi card).

[Jason Dunn]

Then you have no problem right? :wink:

[marketheredge]

Wellllll I suppose. Just geeking out. They say it's better to keep your internal battery topped off, rather than drain it completely (well not completely or you'd lose your data!) before charging again. With that in mind, I am just wondering if it's better to remove the external battery when it starts giving the 'low battery' warning, or to keep using it 'til it flat-out dies.

[Jason Dunn]

Is the add-on battery Lithium Ion or Lithium Polymer? If it's the former, you have no worries. If it's the latter, unless they have a controller to regulate the drain, yes, you could damage the battery.

[marketheredge]

It is lithium polymer, so hmm, maybe I'll ask HP(Compaq)

[tccox]

I seem to remember reading that external battery will never completely drain , at about 20% external the internal battery will take over . I'm looking at the Power status screen on my 3835 right now, external is showing about 20% (just a guess, no numbers on the external battery graph, how odd) internals showing 93% and starting to drop. Course I guess if you just left unit on for several days both would go to 0%