Other Parts Discussed in Thread: BQ34Z100, BQSTUDIO
Hi all,
I have developed a new product with LiFePO4 batteries and I am using the bq34z100-g1 to estimate SoC and SoH of the battery. I have run the GPC to obtain a correct chemID and the result was 445.
One of our customers has reported us in field suddenly SoC drops, usually some hours after fully charge the battery. Analizyng the logs we can see the following steps:
- Battery was fully charged on the 20/01 at 11h51min --> charge final voltage (27500mV) was reached and battery current went under charge final current. Then, remaining capacity (RC) equals to FCC.
- During that day no more energy was introduce to the battery and only some discharge current were produced until 18h. Then, the solar panel stopped producing energy and the battery had the device consumption during night (around 12mA)
- On the 21/01 we can see how the firs big consumption of the day is produced at 8.41h.
- Then, after 3 or 4 peak consumptions suddendly teh RC drops from 2727mAh to 4055mAh.
- However, SoC does not drop until almost 6 hours later.
- This sequence repeats over the next 3 days.
Attached you can find the complete log of the 4 days.
240131_Bq34z100_FieldIssue.xlsx
I have the following questions:
- Why is this drop in remaining capacity occurring?
- Why doesn't it affect the State of Charge (SoC) instantly?
Best regards
