> What are the other requirements?
> Do they have to be in a circular form factor?

The customer specifically wants 2032 sized cells.  There may exist a
square size that will fit in those dimensions, with low impedance.
That may be acceptable, I don't know if part of the energy behind this
is availability at wal-mart.  That would pretty much torpedo the
design entirely since I've looked at the spec sheets of every commonly
available 2032 cell I can find.

> What about square li-ion polymer packs? Those have very good
> discharge characteristics.

No ability to charge/recharge in the system. Manually uninstalling and
recharging isn't practical.

> How big is the device itself?
Barely fits in their intended enclosure with enough room for the 2032
coin cell. The enclosure is mandated by regulations.

> Is the pulse current predictable?

Yes, but it's very complicated, and we are already running as low as we can=
 go.

> If so, even though making use of a super capacitor is
> probably a bad idea (because of leaking what little energy the small
> battery has in the first place), you might be able to use an intelligent
> mechanism with a small super capacitor to charge when you know a pulse is
> needed, and turn off charging the super capacitor when not needed if
> practical.

There isn't anywhere to PUT the supercap.. There isn't any room in the
design budget for it either. And why not run it from a steam generator
powered by wood nymphs?

Sigh...  I asked a specific question, because I have very little room
for compromise in this design problem.  I need something the in the
form factor of a 2032 cell, with roughly the same nominal capacity,
with at least an order of magnitude lower impedance.
Please assume I know the boundaries of my problem.


> How many batteries can you stick in the device?

One 2032 cell will fit.  Two won't.
--=20
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