HP97 battery pack rebuild

[Hans Brueggemann]

(02-11-2016 11:23 AM)Dieter Wrote:  

(02-11-2016 11:02 AM)Hans Brueggemann Wrote:  Tch = 1.1 * 2400 mAh / 170mA = 14.12 hours

Hmmm... my HP41 returns 15,53 hours for this. Or 15:31:46. ;-)

ha! you are correct one of my HP-41's ROMs must be bad!

(02-11-2016 11:23 AM)Dieter Wrote:  Finally let's not forget: you may charge the NiMHs for the same time as you did with the old NiCds – and you'll get the same capacity.

i concur

(02-11-2016 11:23 AM)Dieter Wrote:  Longer charging times (up to 20 hours) will yield more capacity than the old cells, and this exactly is the advantage here.

i agree with you that longer charging times will get you more mileage. however, i managed to kill several of those battery packs over time by being "too generous" on charging times. so, i always keep charging below 120% of rated amp-hours.