How Low Can You Go? 11C and 32SII Battery Voltages

[Dave Shaffer]

My wife has a pair of 32SII and an 11C. She claimed a couple of them (and we've now mixed up which was which) were either not working at all or acting "funky."

One of the 32's wouldn't turn on when I got it. I replaced its batteries with fresh LR44s, and it works fine. The other 32 battery voltages were all above 1.5 V, and it seemed to be fine, as well (and was probably the one that was not being complained about).

I then checked the 11C, which seemed to working OK this morning (after resting for a couple of days), and it seemed to be working OK, too. I checked its batteries, though, and two them were at ~1.33 V and the other was at ~1.22 V. That seems rather low, but the 11C (and siblings) are legendary for their long battery lives. So, I put the old batteries from the non-functioning 32SII (which were reading about 1.47V under no load) into the 11C, and it works fine (and the display may be a bit crisper).

So, I will retire/recycle the old 11C batteries, but wonder

1) How low can Voyager batteries go, and still provide reliable service?

and

2) How low can the voltage be for reliable 32SII functioning? I was a bit surprised that at 1.47 V the calculator did not seem to work.