I just got a Mugen HLI-E61XL here; it's intended for the Nokia E6[12] which takes the same BP-5L as the N800, and comes with a cover suited to that, and (unsurprisingly) not at all adaptable to the N800. But the battery seems to work, and I thought I'd post a few pictures.

For the properly adventurous, and willing to make their own battery cover, this could go a long way towards a maxed-out N800, with built-in 2.75G, extra battery, and maybe a couple other odds and ends as appropriate.

You can see that the battery sticks up almost (but not quite) flush with the webcam/stylus curve; any backdoor will in fact protrude beyond that. Unfortunately, there are no appropriate holes next to the right end of the battery, or one could consider screwing the battery down and making the cover flush with the battery.

The main difficulty the new battery poses is partial interference with the latching mechanism; this makes it look like it may be easier to make a new door from scratch than add a bubble to the existing door.

There's no risk of interference with the kickstand... yet. (My particular back-pack may have issues when I get the express-card support in; we'll see. If all you wanted was a 3.6Ah battery and a couple 32GB flash drives, you'd fit it no problem.)

Anyway, here are the pictures; I expect few will actually be interested in making a new backdoor to use this, but it's good to know your options, right?

Add a keyboard in a clamshell and you got yourself a Pandora :-)

Nope, Pandora doesn't have 2.75G data + GSM voice. (Or, more generically, an ExpressCard/34 socket with a $100 card in it.) This will, if all goes well.

And alas, this is slower. OTOH, it's usable now, and just might be completed before people get their Pandoras. (Probably not, though; I'm too busy, so it'll probably be fully operational, but replete with ty-wraps and baling twine.)

How do you connect the expressCard ? deep surgery ?...

Well, that comes later, but only the USB interface; either to the 4 test pads on the PCB (great, if I can make it work), or with a little cable going around to the mini-B port. Power, of course, has to be provided too, as the N800 isn't going to source whatever unknown current that card uses. I'm undecided whether to slip in contacts between the battery and the N800 contacts and use a DC-DC buck converter or just a separate battery pack... I'll be posting on that, once I get all the pieces here and functional.

If you meant mechanically, I'm using one of these.

Hi,

The battery can be used in the N810?

No this battery cannot be used in the N810, but there's one for the N810 that comes with a door made for the N810.

OK!

I found the battery for N810 at the site of MUGEN.

It is really cool!

thanks

OK, battery life confirmation: Using my tablet "normally", with no more charging after initial top-up (which completed shortly before my OP above), it's down to 10 hours standby. So, I'm guessing, it would make it a total of 12 hours, if I weren't putting it on the charger now. That includes pretty much continuous decoding (MAD, on the ARM) of 256 ~ 320 kb/s mp3s, output mainly through speakers (~2/3 volume), but some with earbuds (~1/4 volume), and a little HSP, as well as intermittent mapping (MM, BT GPS) and internet (BT DUN and WiFi).

That's at least twice what I'd expect normally, so the battery seems to be doing its job.

EDIT: Turns out I was running with the performance governor, so that was 400 MHz for 12 hours.

One word : wow :-)