At 13:18 07/04/97 -0600, you wrote:
>We have a project that requires -40 degree (C or F, you choose) operation.
>Anyone know of a battery supplier that provides something that works
>reliably at that temperature?
>  <edtodd@sni.net>    Ed Todd

How much power do you need? If your power requirements are small there are
quite a lot of lithium/thionyl chloride batteries available. Some are
specified to operate down to -55C (Saft and Crompton both make them).
Lithium/Iron Sulphide batteries will also operate down to -40 and offer
higher peak currents but lower total capacity.

Whichever you choose, remember that the capacity and voltage both drop
dramatically at low temperatures. (I guess you've discovered that already :)

Hope this helps,

Keith.
==========================================================
Keith Dowsett         "Variables won't; constants aren't."

E-mail: kdowsett@rpms.ac.uk
   WWW: http://kd.rpms.ac.uk/index.html