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Old 03-24-2012, 06:58 PM   #53 (permalink)
Alcibiades Ramos
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Join Date: Mar 2012
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For lithium iron phosphate cells it is more important that, when discharging, they don't go under. Their safe bottom is around 2.7 volts. Below that the discharging curve is steep and they are prompt for reversal, in other words they die.
There is unfortunate notorious case with a guy that left his Tesla in a warehouse because he was moving and never charged the cells in that period. He lost the whole pack at U$40K.
Whoever uses lithium has to keep his/her cells between 2.7v and 3.8v at the most. Once you bottom balance your cells you almost don't have to worry about the top end. You just set up the charger to cut off at the whole pack's nominal voltage and cells take care of themselves. You don't bottom balance and they are an accident waiting for a place to happen.
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