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Old 01-07-2012, 10:01 PM   #33 (permalink)
IamIan
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Quote:
Originally Posted by MetroMPG View Post
With a relatively low current 350 mA grid charger, we would need to wait a long time for the last cell in the pack to peak & decline in order to bring things into balance if they've drifted out of whack.
FYI
The slower the rate of current the smaller the -dV ... eventually it gets so small that it would be in the range of signal noise sized change in voltage ... also keep in mind the -dV of one cell can be disguised when one is looking at the total sum voltage of all 120 cells in series ... at small enough currents for NiMH ... the alternative often used is to take advantage of NiMH's superior abuse tolerance , and just continue to slowly overcharge everything until the voltage levels off... like you indicated ... that can take a considerable amount of time to 100% finish up ... but some topping charge will result in some better SoC balance ... even is not long enough to be 100% topped off.
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