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Full Version: Charging NiMH cells on calculators
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Hello All,

Does anybody know if it's recommended to charge high capacity NiMH (2500mAH) instead NiCd cells directly on the calculators (i.e. Spice series) using its original rechargers? And what about the other ones (Classic, Woodstock, etc.)?


Luis; In my humble opinion, it is never a good idea to charge batteries inside a spice or woodstock. Doing so with a bad connection at the battery terminals is what has probably killed many of the dead units you see on ebaby - you know; the ones described as "untested".

I was told by Etienne (one of our fellow collectors and Mr FixIt btw) that Woodstocks don't like rechargeables either and last longer with alkaline batteries.

In my experience they "like" rechargeable cells (NiCd or HiMH) just fine, but it's recommended to recharge them outside the calculator to avoid possible damage.

Alkaline cells provide a higher voltage than the calculators were designed for. I haven't heard of damage resulting from that, but it is going to stress the components more. Many people will tell you that's not a problem, but I personally prefer to avoid it.

I have used alkaline cells in my spices with no bad results but i have always put in slightly used or old ones. I think that it was the inimitable Norm who suggested this, on the age old theory of "couldn't hurt". There are always some used AA cells floating around in something. Still; i prefer nimh that were charged outside the calc.