Calculator collection : How to power calcs without constantly opening?

[EugeneNine]

(12-01-2021 12:02 PM)mfleming Wrote:  

(12-01-2021 02:18 AM)EugeneNine Wrote:  I've had more Rayovac's leak than any other AA, then Energizer and then Duracell. Manufacturing lines change from time to time so the battery you buy today isn't the same as the one you bought a decade ago.

Well known brands should have their manufacturing process down pat so you would only get the occasional tail of the distribution. I've had a couple of Energizers leak, but only because I buy far more of them than Duracells. Relabeled house brands (hardware store, grocery store) always seem to leak!

They make updates every now and then though, might not be often but things change. Sometimes upgrading to new equipment, change of supplier, etc.

[mfleming]

(12-01-2021 02:21 PM)Ren Wrote:  Duracells have gotten worse since Procter and Gamble bought them out.
They have milked the "reliability" cow dry, while making the batteries cheaper.

That's bad news! P&G is not exactly known for quality. Appreciate the tip.

[cdmackay]

I've had several sets of Duracells leak, and ruin equipment, in the last few years. Various remote controls, etc, where they've sat for years.

I still use them in my HPs, but I change them out once a year, and hope that's frequent enough.

[EugeneNine]

Its funny because I've had more Energizer leak that duracell and more rayovac leak than all the rest combined.

The NiMH I had leak were an off brand closeout and Radio Shack

[Craig Bladow]

My experience for leaking batteries is Duracell leaking less than Energizer. I remove batteries from all stored calculators and periodically inspect. For HP-41 I use NiMh cells.

Responding to the original question you could possibly use inductive coupling to charge a super-capacitor mounted inside the battery compartment. This would let you use the calculator untethered for some amount of time. The usefulness of this depends on the amount of energy that could be stored in the capacitor and the rate of use by the calculator.

[Archilog]

Good evening,

It was probably said before, but I avoid your (smart?) solution by using a calculator for a while (two weeks - two months or more) with good rechargeable accus and then after, remove the batteries. Exceptions are my HP-29E, a PSION 7 and a PSION 3mx, permanently used.

It is clear that I am therefore not using my HP-37, 38s, 21, 22, 25s, 41s, 18, 28s (and so on) very much, which should need an inspection usually every year at least, but I am also not so disciplinate... For the best and for the worst.

Take care ;)