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BQ40Z80: LStatus vs UpdateStatus

Part Number: BQ40Z80
Other Parts Discussed in Thread: BQSTUDIO

Hi Team,

My customer is trying to "force" cell balancing on their bq40z80 pack by programming UpdateStatus to 0E, but have the questions below. Can you please provide feedback? LStatus 0x14 appears to be an invalid value based on the TRM:

Can you clarify the difference between LStatus and UpdateStatus? At first glance they seem to be the same, but after some experimenting I see some differences.

If you program UpdateStatus from 06 to 0E, this fictitiously tells the gauge there was a field update QMax to enable balancing. It also changes LStatus from 06 to 14 instead of 0E as well, where the 1 is an unknown from the TRM. Then the reset takes an OCV reading and calculates the cell balance time. The problem I see with this is that it is calculating the cell balance time from old or default QMax values and could actually further imbalance the cells without a proper update. For large format batteries, does this mean that you would have to run many learning cycles in order to fully balance? What happens when the battery reaches FC before the balance timers fully count down? What is the largest number the balance times can be?

After the field Qmax update occurs and sets the flag, does this flag ever reset back to 0, say when max error goes above a certain percentage?

If you set Update Status to 0E and LStatus becomes 14, if you run a learning cycle, will LStatus eventually become 0E?

How much more accurate is balancing using capacity vs delta V given they were both balancing at the same temperature and current?

Is there a way to command each individual cell balance on, say with a custom .Srec file?

What gets reset on a commanded reset?

Thanks,

Antonio