BQ28Z610: SOH didn't update

Jason Change

Intellectual 370 points

Part Number: BQ28Z610

Hi Team,

I have a battery pack with BQ28Z610.

The design capacity is 5200mAh, I checked FCC is around 3346mAh.

Based on calculation result, the SoH should be 64%, but I saw register table SoH is 83%.

Why SoH didn't update to 64%?

over 4 years ago

0 Jessica H. over 4 years ago

TI__Genius 11535 points

Hi Jason,

It looks like the file or image you tried to attach is broken. Can you repost it?

0 Jason Change over 4 years ago in reply to Jessica H.

Intellectual 370 points

Hi Jessica,

I hope you can see it.

0 Nick Brylski over 4 years ago in reply to Jason Change

TI__Mastermind 19195 points

Hi Jason,

You will need to identify your chem id, program it on the gauge and then carry out a learning cycle first before the SOH reported by the gauge can be trusted.

Refer to 6.7 of TRM for more details on SOH.

Best regards,

0 Jason Change over 4 years ago in reply to Nick Brylski

Intellectual 370 points

Hi Nick,

Thanks for your reply.

I already choose correct chem id and finish learning cycle for this battery pack.

I know FCC value based on many parameter to predict such as impedance, temperature, voltage and current.

From TRM6.7, the SoH is FullChargeCapacity()/Design Capacity().

FCC is 3346mAh and design capacity is 5200mAh.

Thus, the SoH should be 64%. My understanding is correct or not?

Regards,

Jason

0 Jessica H. over 4 years ago in reply to Jason Change

TI__Genius 11535 points

Hi Jason,

Where did you get that snippet? The current bq28z610 Technical Reference Guide includes the following snippet:

0 Jason Change over 4 years ago in reply to Jessica H.

Intellectual 370 points

Hi Jessica,

Thanks for your reply.

Long time ago I download BQ28Z610 TRM from TI website, so the SoH description copy from C version.

I will study it with D version.

Regards,

Jason

Power management

Power management forum

BQ28Z610: SOH didn't update