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UPDATE: New batteries in old HPs

Posted by W. Bruce Maguire II on 31 July 2001, 3:34 p.m.

Hello all:

I just wanted to amend the previous post I had written about modifying a charger to charge 1600 mAh NiMH batteries. It appears that I recommended too long a charge time. It seems that about 4 hours is more appropriate for the charge current of 175 mA that I quoted.

I figured this out by looking at the charging current of two "smart" NiMH chargers I have. The energizer (I think) charger used 135 mA to charge AAs in about 6 to 12 hours, then dropping to 25 mA as a maintenance charge. The quick-charge charger I have used 225 mA to charge in 90 minutes, then dropping to 17 mA for a maintenance charge.

Please base your charging times on theses numbers. My recommendation would have resulted in charging the batteries for too long.

Thanks, Bruce.


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