Laptops Powered by AA Batteries

Back when Mp3 players were a thing (before the iPod) Archos were making an MP3 player which took 4 AA, and the mail list for alternate runtime (rockbox) was full of discussions about NiMH trickle charging, approaches to maximising battery life, as were Apple Mouse conversations. People went wild for the most long lived, fastest recharge AA.

In some ways, I think it's a shame we didn't go to consumer goods run on Lithium batteries but in this form factor, with discrete charge management cards. So for instance, replacing the batteries in a Thinkpad could have been commoditised.

Bagged cells are damn good for small devices, but they do make it harder.

My Minidisc players were equally 'my battery, my form factor' as are most digital cameras. I guess some people (Dyson) cannot go past the opportunity to make accessories and replacements bound in them, at their price. After sales income is big.

The unit I had also. I put a larger hdd in, I think CF would have been neat. The recorder function was good

I had the Atari ST Book. Somewhat dreadful machine.

And I had the Amstrad PPC 512 portable which could also be powered by ten regular C-cells. It would eat NiCads by the hour.

And I also had the Sinclair Z88, which lasted about a week or two on a few AA batteries which I used all through college because laptops were new and bulky and the keyboards were noisy and so a number of professor's banned laptops, but the Z88 with its squishy dead-flesh keyboard was all but silent.

The great thing about the Z88 was everything was pre-loaded on to ROM, and your documents held in battery backed RAM for weeks at time, though you flash your files to the EEproms for safety. There was enough capacitance in the Z88 that if you pulled the batteries out to change them for fresh ones, you had about two or so minutes before the contents of RAM was lost.

A friend of mine, Ken, (who worked for Apple at the time) has a prototype Apple portable (pre-powerbook, IIc line I believe) that runs on C-cells. He keeps it on top of his fridge.

Seems like the EU laws are going to fix this problem soon!

It sucks that we don't have a universal battery standard for lithium yet though. Seems like at the very least, the OSHW community should have one.

We could have separate charge and discharge pins, and I2C data, so everything stays chemistry-agnostic, and you could parallel two batteries just with diodes on the discharge pins.

You could have all the connections on one side, and only have one width, just different lengths, so the small ones fit anything with just a a spacer block.

Or you could even specify an integrated screw hole.

What computer-like devices still use AAs? The only ones I can think of are some of Garmin’s GPS units. (There the user-replaceable battery, in a standard format you can buy from any developing-world shop, is seen as a big plus by many users. But one dreads that such units will eventually no longer be offered, replaced only by USB-charged batteries, just because that’s how things go nowadays.)