Li-Po

[amhay]

Hi all,

I have got a li-po battery which I am very happy about :-) how ever I have a few questions:

Does any body knows if the cut off voltage of the 48v controller (44.5V I think) is ok for the li-po bat.?

Does a li-po battery has to be charged all the time like lead acid in order to extend the life cycle?

Is there over charge protection?

thanks,
Amit Chai

[OneEye]

1.  How many cells are in your 48V battery?  Recommendations I've seen for lipo are around 3.0V per cell, anything below 2.5V per cell is dangerously close to permanant discharge.  Are you sure the LVC is 44.5V on the 48V controller?  I would have expected 42V (10.5V/battery) for lead-acid cutoff.

2.  Most lithium chemistries self oxidize and degrade at both high and low state-of-charge.  Longest life would be if you kept the battery in the 30-70% range.  This effect appears to be less prominent for lithium-iron-phosphate chemistries.  So for storage, charge it up to about 1/2 way (then keep in the fridge.)

3.  Overcharge protection will be specific to your charger and any BMS built into the battery.  The controller is not involved in the charge cycle.

[amhay]

there are 16 cells. And I think you are right it is 42V cut off voltage which is 2.51 per cell still about 2.5.

From what I have red the best is not to discharge below 2.8/per cell, and to try to avoid deep discharge cycles.

So far I have not had problems with, it I go at around 41 km/h (26")on the flats I have only discharged it to 49v and that was after I drove 20 km.