HP 41 Battery Pack


I have a battery pack for my HP41. It came with the machine when I bought it. It has never been used. I don't have the charger for it. Do these packs deteriorate?
What is the charging voltage and can you recommend a method of charging this pack. I don't want to go to the expense of buying a charger if the battery pack is shot.
I have a battery charger for HP 45 and Hp 33C. Can I take leads off either of these and connect to the battery pack? If so what is the polarity?
Thank you in advance.


Yes, all batteries have a finite life, even when not used.

If the pack is a rechargeable ni-cad (82120A), you'll need to re-cell it with 1/3 AAA cells as the original 1/2 N cells are no longer made. The proper charger is HP 82059B, output is 8 VAC @ 3 watts.


I have an 82059D charger with the same specs, I wonder how it differs from the B model? Also, where do you find 1/3 AAA cells? Is there an article on how to open up the 82120A?

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