BQ40Z80: full charging bit is set when in the learning cycle

Mohan Raj

Part Number: BQ40Z80
Other Parts Discussed in Thread: BQSTUDIO

Hello Team ,

i just started my learning cycle connecting the battery setup , my battery cell are Lion cells (3 cells) part number US18650VTC5A so the chemid is 0x2161

.programmed the chemid started the learning cycle. i didnt set the parameter from my side , bcoz already i flashed the chemid.

i charged my battery in 12.6 v and C/2 ratio current (2600/2 = 1.3 A) , battery get charged 12.6 but my BQ shows 12.6 instead 11.5 volt.

my FC bit is also not set , so what voltage i need to set in power supply to get my battery fully charged. Could you please help me.

Regards

Sachu

over 2 years ago

0 Wyatt Keller over 2 years ago

TI__Guru** 105590 points

Hello Sachu,

I'm not sure I understand your question. It sounds like you charged to 12.6V and the gauge is reading 12.6V which should be correct. Why would it show 11.5V?

Just because the chem ID is uploaded does not mean you don't need to set the other parameters outlined in the learning cycle guide, like Dsg Current Threshold, Chg Current Threshold, Quit Current, etc.

Also for any learning cycle questions you should always share the .gg file from before and after and the BQStudio log of the test being performed.

Sincerely,

Wyatt Keller

0 Mohan Raj over 2 years ago in reply to Wyatt Keller

Prodigy 200 points

charging_charging.gg.zip

Please find the log . in battery it fully charged with 12.6 . but in BQstudio shows 11.6 volatge and FC bit also not set?

Let me know which parameter BQ will understand the battery is in full charge

0 Wyatt Keller over 2 years ago in reply to Mohan Raj

TI__Guru** 105590 points

Hello Mohan,

This looks like an issue with your charger, the current profile is extremely noisy and erratic. Also it looks like the charger starts the taper too early if you are trying to charge with 12.6V. It could also be a bad connection since it looks like there is a difference between the PACK voltage and BAT voltage.

Sincerely,

Wyatt Keller

0 Mohan Raj over 2 years ago in reply to Wyatt Keller

Prodigy 200 points

Hello wyatt ,

what was the expectation in charging both BAT pin volatge and Pack pin voltage ? whether at the time of charging both will be equal or not?

let me know whether we can proceed with EVK or not

0 Wyatt Keller over 2 years ago in reply to Mohan Raj

TI__Guru** 105590 points

Hello Mohan,

I mean a bad connection on in the terminal connections on the EVM, not the EVM issue itself.

Sincerely,

Wyatt Keller

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BQ40Z80: full charging bit is set when in the learning cycle