How long should I charge the batteries


I have rebuilt my 45 battery pack and used 650mAh NiCad. I believe the original was 450mAh and had to be charged for 14h. Am I right in thinking I should charge mine for 20h.

Thanks for your input



I've always used the following for NiCds:

(1.5) times (battery capacity) divided by (charger capacity) = hours

Assuming the HP-45 charger is 50 ma, then

1.5 x 450 / 50 = 13.5 hours

1.5 x 650 / 50 = 19.5 hours

So, 20 hours should be about right.


Most of the original HP packs were 600 maH. Some very early ones were 500.



Charge them all the way to the end, right from one end to the other. Anything else leads to a big bulge at one end and then it won't fit into the battery compartment.



PS: Sorry for the's just a wild reaction against a very crap week...

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