[mkreis]

40 hours with a coin battery is impressive, but I think it is a bad decision in terms of environmental friendliness.

[guenthert]

"The Lisp Badge LE draws only 6mA from its CR2032 button cell, and so should have a life of about 40 hours"

I suppose that's 6mA when the CPU (MCU here) is active. In idle mode that ought to be much lower (the low power monochrome display, not eInk, draws only 30µA as stated separately). Does uLisp support idle mode? Uh, apparently not automatically, but requires the user to call a SLEEP function ...

[herewulf]

Indeed. Are there rechargeable coin cells?

[anonzzzies]

Yes, look for LIR2032 batteries.