> >> I am going to heat a small
> >> object to about 28C to 32C.  The object is insulated and thermally
> >> conductive. Ambient will vary from 0C to 20C.

> Batteries don't like too low temperatures, and the target temperature
> the OP wants (28 C to 32 C) is well withing the operating ranges of most
> batteries, so I would suggest putting the battery in contact with the
> object that needs heating (inside the thermal insulation) then he will
> use every bit of heat produced.

.... also, many batteries lose a substantial amount of their capacity
at temperatures approaching 0 degrees C.
Having the battery in the warm space, if feasible, or in a warmer than
ambient space, will help performance at low ambient temperatures.

_____________________

This 'requirement' suffers from the same fault that many semi-secret
ones do - the trye requirement is not fully specified and it takes
"death by a thousand vuts/questions" to find out what is really anted.

If this is not secret, does not involve black helicopters and tinfoil
hats or ... then telling us what is really wanted would greatly help
the abilit to answer well.


         Russell
--=20
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