Other Parts Discussed in Thread: BQSTUDIO
Hi. I am having problem with BQ27510-G3 gauge.
I have written Design capacity(subclass id- 48) to 1800, Qmax Cell 0(subclass id - 83) to 1800. No other parameters have been edited from default ones.
I did a couple of charge/discharge cycles for multiple batteries and there is one issue, which is best seen in graphs below:
It seems like there is no problem with discharge RemainingCapacity and SoC drops steadily, but when charge begins suddenly FullChargeCapacity starts to drop until it gets to
default FullChargeCapacity (100mAh). Also SoC% is at 100% when the battery charge is at 1000mAh.
Is there a parameter that I am missing ? I know that for best results I would need to use BQStudio and do multiple tests, set Chem ID etc. but we would like this battery
thing to stay as trivial as possible as we are not aiming for best results and would like to avoid increased production costs.
---------Edit------
I checked flags of my log files and notice that gauge does not detect FullCharge and does not set full charge flag. I increased taper current a bit(100mA->115mA), but now I have 2 other strange issues.
Full charge capacity drops from intended one to 950 almost instantly at the start of the test. See image below. From Average current I would say this happens when I disconnected USB cable of device and it stopped charging and started discharging the battery.
Also during this test RemainingCapacity is not increasing steadily at TamperCurrent levels, but fluctuating with 1 mAh amplitude. In first tests(above edit) RemainingCapacity was increasing at taper current levels too.
So in this test, because of RemainingCapacity not changing enough during end of charge, gauge did not detect FullCharge again.
Why RemainingCapacity is not changing correctly? See images below. Any help will be appreciated.
