Part Number: BQ40Z50-R2
Hi,
I have a project which is using BQ40Z50RSMR-R2, I got below questions from my customer, I copied it below, could you please help to answer the questions:1)why the "Max error " changes from 1% to 2% after some rest without any operations? 2)how does bq report Max error as 1% or 2%? 3)is it normal "Max error" changes from 1% to 2% after rest without any operations? 4) if it is not normal, how to repair?
1. “Max error” of the BMS is not stable. Sometimes it shows 1%, sometimes it shows 2%. Last week when we tested 520-530pcs ok, their “Max error” showed 1% at the beginning, after several days rest without any operations, it becomes 2%. We checked with the BMS manufacturer about the parameter “Max error”, the BMS manufacturer did not give a clear reply. We need to know “Max error” can be 2%, or it should be 1%? We checked the TI’s working principle, in theory, 1% is the impedance tracking state, and 2% is the capacity learning successfully. Both values are acceptable. But the question is, why the “Max error” changes from 1% to 2% after some rest without any operations? Does it mean the BMS is not stable? In fact, we wish to get a clear reply from the BMS manufacturer. If this is normal, we will seal the batteries to arrange the shipment. If it’s not normal, please tell us how to repair?
Thanks,
Joy
