How to change batteries on HP 21


Hello All,

I just got a HP 25, but I don't know how to change the battery pack. It uses 2 batteries, but I don't know how to take them out.

Any help will be greatly appreciated.


I have done this also on my old 25, and you can see a seam along the edge of the pack just above the back of the battery pack (i.e., the outside). You can carefully remove the back from the "frame" of the pack and pull the batteries this way. NiCad AA batteries work very well for this.

Also, Katie Wasserman has written a very good article on this topic:

There are other articles and as I find them I'll put them up also.



I managed to replace the cells in one of my packs by cutting one end of the bar which runs along down between the cells. by carefully bending this partway I was able to get both cells out. I replaced them with 1200mAh NiMh cells several years ago and they work just fine. I charge them a little longer than normal with the standard HP charger.

Hope this helps.

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