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Inexhaustible batteries?

Inexhaustible batteries?

Inexhaustible batteries?

In 1984 I bought a CASIO scientific calculator fx-100 which included 2 AA 1.5V alkaline Casio batteries [Casio Mabic C8501]. I have been using this calculator every single day throughout my student and professional life (total:28 years) with the SAME two batteries. I have written to CASIO asking them how could this be possible but I was ignored. I have asked several specialists and they were all very surprised. Could anyone please give me a logical answer?

RE: Inexhaustible batteries?

The calculator uses very little power and the batteries are good quality.

RE: Inexhaustible batteries?

Thank you hydroman247, but still, 28 years?? Everyone else has told me that it's impossible.

RE: Inexhaustible batteries?

OK - it's impossible. Maybe you changed them in your sleep or something??

Congrats on 28 years - AMAZING!! I have had 2 year old batteries burst!!

RE: Inexhaustible batteries?

Coincidentally, in 1984 while visiting Hong Kong, I bought an Icom IC-02AT walkie talkie. It contains a wee little battery (soldered in button cell) that holds up the memory (RAM). That little battery is still working.

RE: Inexhaustible batteries?

Are you sure that's not one of the early solar calculators? lol

RE: Inexhaustible batteries?

Are you sure this isn't like the prank where someone keeps fiddling with the victim's cane to make him think he's getting taller?

Maybe someone's been changing your battery for you?

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RE: Inexhaustible batteries?

I suspected I would get a lot for funny replies. Since my calculator is a museum piece, no one ever touches it. I'm not a battery expert but the code "C8501" could it be the supposed expiry date [Jan '85]. The irony is that the manual mentioned that "the batteries that come with your calculator when you purchase it are for testing only. It may not provide full service life". I would love to have the nuclear ones that CASIO recommended!!!!

RE: Inexhaustible batteries?

The manual says you should get 17,000 hours of continuous display. So the batteries are super-sized for the application. If you test the batteries they would probably be considered "dead" for most applications.

RE: Inexhaustible batteries?

17000 hours continuous would provide you 1 hour per day for 46 years. Not bad. clown

RE: Inexhaustible batteries?

This thread is making me want to dig out my old calculators from the 1970s and fire them up.

They'll probably need new batteries.

RE: Inexhaustible batteries?

Quote (oliamel)

I'm not a battery expert but the code "C8501" could it be the supposed expiry date [Jan '85].
That's awfully close to a battery type designator...

CR would mean lithium manganese dioxide chemistry, but you have just C. 8501 would be dimensions of 85mm x 01mm. I'm going to guess the battery doesn't look like that ;)

Dan - Owner

RE: Inexhaustible batteries?

I've had a number of Japanese products that came with privately branded alkaline AA batteries that lasted over a decade. The replacements never last half as long. Don't know what they put in their batteries but it's obvious the Bunny doesn't know either.


The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: Inexhaustible batteries?

All a bunny knows is how to make more bunnies!!

RE: Inexhaustible batteries?

Or more batteries...

Most of mine leak if they have been left installed for years. It's entirely plausible to me that there is a way to make a long life battery that will survive the ravages of time if the demand on it is low. But I can see the likes of Mallory not wanting that to be the standard product design because they would not sell as many batteries.

"Dear future generations: Please accept our apologies. We were rolling drunk on petroleum."
— Kilgore Trout (via Kurt Vonnegut)

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