BQ40Z50-R1: Remaining capacity estimation after 5 hours relax time in LifePO4 battery

Ravid BY

Part Number: BQ40Z50-R1

We are using 4S1P 25Ah lithium iron phosphate (LifePO4) battery.

We are experiencing an odd behavior while charging the battery to full while using CC-CV charger with taper current of 1A.

After battery fully charged (RSOC = 100%) and relaxed for 5 hours, the remaining capacity gets updated and RSOC drops to about 70% after "Relax smooth time" that is 1000 seconds.

This happens while nothing loads the battery.

Is it suppose to work like that? If yes, can we disable it?

over 6 years ago

0 Batt over 6 years ago

TI__Mastermind 42535 points

Have you programmed your chem ID correctly? That is one reason why you can see capacity drops with the LFP cell.

0 Ravid BY over 6 years ago in reply to Batt

Intellectual 330 points

Hi Batt

I think my chemID was not correct. I have replaced it with a correct one and it looks OK but still checking..

Thanks!

0 Batt over 6 years ago in reply to Ravid BY

TI__Mastermind 42535 points

Hi Ravid,

I think this should resolve your issue. Please contact us if you need more help.

0 Ravid BY over 6 years ago in reply to Batt

Intellectual 330 points

Hi Batt,

I just wanted to update that the issue was solved after changing the ChemID to the correct one.

Thanks!

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BQ40Z50-R1: Remaining capacity estimation after 5 hours relax time in LifePO4 battery