Hello everyone!
I am using a BQ78Z100 device with 2 550mAh LiPo cells in series. The cells are definitely not charactarized by ti so I did the chemID calculation using the GPC Tool. I got a match with a maximum DOD error of 2,92%. Attached you find the complete log file and the roomtemp_rel_dis_rel.csv of the charge-rel-discharge-rel cycle i used to determine the chemID as well as the report file I got back from ti.
After setting up the chemID i wanted to do a learning cycle: I discharged, waited for VOK to clear, charged up the batteries and waited again for VOK to clear... all fine so far! My update status register has the value of 0x05.
In the following learing cycle I am expecting the restistor tables to update which should result in an update status register value of 0x06. But after discharging a while, the RDIS bit sets which means - if i got it right - that no updates of the Ra tables take place. I observed, that the Cell1 and Cell2 Comp Res values were negative at this time (they were positive before). After finishing the discharge and relaxation phase i checked the update status register and the value was still 0x05. So no update of the Ra tables took place.
I read some posts here in the e2e forum about this issue and the reason maybe a wrong chemID... but now I am a bit helpless, because I found this chemID using the GPC tool.
Unfortunately i didn't record the learning cycle... but I just started a second one and I can provide the data on monday.
Can anyone help me with this issue? I am not using an EVM, but I simply copied the schematics and put it on a PCB which maches my form factor. So it is basically the same!
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