On 06-08-21 23:05 +0100, Mike Morley wrote:
> 
> 
> For robotics within the department, ~2.5AHr batteries at a nominal 12V:
>  - NiMH pack - lighter, but considerably more expensive. We're 
> currently experiencing problems with our charging circuits.
>  - Sealed Lead-Acid - heavier, but around 1/3 the price of the NiMH 
> packs. I've got a working demo sitting on my desk, and am currently 
> routing a small PCB.
> 
> For the PDA being developed, we obviously had to go with Li-Ion for the 
> weight saving, and - for convenience - I selected the Nokia BL-5C 
> battery - 900mAHr at 3.7V. 

Mike, this is intersting stuff I didn't know about - could you add
your battery/PCB info to the wiki? 
http://balloonboard.org/balloonwiki/BalloonPowerOptions

> The beauty of these are we can run them in 
> parallel to get almost 2Ahr, and they're easy to charge -- either in a 
> Nokia desk charger or a phone like the 6230i (Which both I and Chris 
> Jones have)

And I've got one too :-)
 
Wookey
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