On 12/15/05, M. Adam Davis <stienman@gmail.com> wrote:
> As there are no other requirements (cost?  :-) ) then I would go for
> individual SLA cells.  Four will give you 8V.  Pay careful attention
> to charge and discharge and you'll likely have a very reliable, long
> lasting, and inexpensive solution.
>
> It may be worth looking at Li-Ion batteries and their variants due to
> their low discharge.  They aren't that much more dangerous than SLA -
> it's just that when SLAs leak or explode they usually aren't leaking
> or exploding in someone's pocket.  The problem is the cost, both for
> the batteries, and the charge control circuitry.
>
> Lastly, consider a generator/motor with a windup spring to store the
> 1AH you need, coupled with a lithium coin cell or two for memory.  Use
> a catch with a low current solenoid to prevent the spring from
> unwinding when you don't need the large current.  It would only be
> cost effective if you were planning on making thousands, and it would
> require a good mechanical engineer, but it solves a whole bunch of
> problems you don't have, and creates a bunch of others you don't want.
>  Wouldn't that be fun?
>
> -Adam

How about directly solving the problem with a voice alarm?  When the
battery voltage falls, it can call out:

"Hey, lardbutt, shut off the TV and get the treadmill out of the closet!"

Regards,
Mark
markrages@gmail
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