Tool/software:
Hello TI team,
I am typing this message because our customer is facing some odd issues with our batteries using BQ40Z50-R2 (R2.08).
We use to supply the same batteries with older BQ20Z95 and never faced the same issue.
I will try to be as thorough as possible:
The device can be used with one or 2 batteries, the device will manage if it draws from 1 or 2 batteries, but this was never an issue.
The issue is most likely to happen only when 1 battery is connected, but can happend with 2 batteries (meaning that the 2 batteries had the same issue).
There are 2 scenarios when the issue occurs:
- Scenario 1: the device is connected to AC power and running. When unplugging AC power the device shut down ==> the battery is not powering up the device
- Scenario 2: the device is not connected to AC power. We press the ON button to start the device, but nothing comes up. ==> the battery is not powering up the device. This scenario seems to have the highest occurence.
The issue is reapetable but looks quite random.
The batteries are not in shutdown mode because we can get the voltage from P+ and P-, we can read data with BQ studio and we have a push button to light up LEDs to check SOC directly on the battery and they do light up.
When consulting the data (Lifetimes) from the 2 batteries (I have the logs and can provide them) that have the most occurence of the issue, we only saw a high number of ASCD events (one was over 10K and the other over 500) that would be strange. So we dug into the data from the TI website and saw that the newer BQ40Z50-R2 FW (2.11) was able to correct some unwanted events such as ASCD.
Today we flashed 2 batteries with 2.11 on customer side and, this is very early stage, the issue still occured but it seemed with less occurence. But again this is very early stage and we only have done a few tests and we will continue to do more. And let you know.
The fact the issue can be more present on some batteries than other and being so random leaves us a bit wondering where the issue could come from. That is why I am typing this message hoping you could see something that we don't.
thanks in advance.
Best regards,
João
