TI claim that you can charge LiFePO4 cells by CC (constant current) charging as usual but to a higher than usual voltage (eg 3.7V rather than the usual 3.6V for LiFePO4) and then step transition to a lower float voltage with NO intermediate CV mode.
Their bq25070 IC implements this method as described in the bq25070 datasheet.
This goes against ALL other advice, IC specs and charger circuits that I have seen.
Doing this with Vcv <= 3.6V is fine enough - with or without a CV stage. It's the extra voltage and no CV mode that is radical. The implication or statement from all other sources is that exceeding the normal Vmax of 3.6V for LiFePO4 by even a small amount is liable to be damaging or fatal.
Have TI gone utterly & irresponsibly mad or is this a fantastic new way to charge Lithium Ferro Phosphate cells?
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