BQ40Z50-R2: Chemistry ID

Zhihan Zhang

Part Number: BQ40Z50-R2
Other Parts Discussed in Thread: BQSTUDIO

Hi TI Team,

I'm having a 3S3P battery that the original learning cycle was successful. However, this battery will be used for 10W, 20W, and 62W discharge, which are equivalent to 1.11W, 2.22W, & 6.89W per cell discharge. So I want to find if there is other chemistry ID available to optimize my application. So I did 3 cycles on cell level and record the data. Then upload the data through GPC tool. And have some issues. Please see below.

1. For 10W or 1.11W/cell, the report says recommended chem id is 2405. However, after i update the newest chem id (ver 843), i still can't find 2405 in bqStudio.

2. For 20W or 2.22W/cell, and 62W or 6.89W/cell, the returned reports has generally no contents or recommendations. And no error message was reported via email as well.

Also attach the data and their reports. Please kindly advise what to do next.

Thanks,

Zhihan

over 4 years ago

0 Wyatt Keller over 4 years ago

TI__Guru** 105760 points

Hello Zhihan,

You shouldn't need to use multiple chem IDs for the same battery cell, I would use the single cell chem ID recommended.

You must click the "Include chemistry IDs which don't support turbo mode 2" check box to see all available ID's.

Sincerely,

Wyatt Keller

0 Zhihan Zhang over 4 years ago in reply to Wyatt Keller

Expert 1100 points

Hi Wyatt Keller,

Thanks for the instruction! I did find 2405.

I didn't intend to use mutiple chem ID. Because we have application using 10W, 20W & 62W, so I just want to see if for different power, different chem IDs will be recommended. If so, we will test on the recommended chem IDs then select one for our application.

So can you please review previous uploaded reports for 20W and 62W and advise why there is no recommendation or content in the reports?

Thanks,

Zhihan

0 Nick Brylski over 4 years ago in reply to Zhihan Zhang

TI__Mastermind 19195 points

Hi Zhihan,

It may be due to the temperature variation that no match was found. Can you try again with less temperature variation.

Best regards,

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

TI__Mastermind 19195 points

Hi,

The Dsg rate should be C/5-C/10 anything too high gives too much error. also generally need to charge to the CV of the battery specs and not the application voltage. 4.1V does not represent a real battery profile

Best regards,

0 Zhihan Zhang over 4 years ago in reply to Nick Brylski

Expert 1100 points

Hi Nick Brylski,

Thank you for your reply!

So if I want to select a potential better chem ID for my applications (10W, 20W, 62W DSG + 4.1V ~ 3.1V de-rated), what data would I need to collect in order to get the recommendation on chem ID?

Thanks,

Zhihan

0 Nick Brylski over 4 years ago in reply to Zhihan Zhang

TI__Mastermind 19195 points

Hi Zhihan,

Use the chemID that was found from the 10W discharge. This will be ok for all other discharges rates.

Best regards,

0 Zhihan Zhang over 4 years ago in reply to Nick Brylski

Expert 1100 points

Hi Nick Brylski,

Thank you very much for your suggestion!

As you mentioned that "4.1V does not represent a real battery profile", should we re-run 10W discharge but with full voltage range from cell spec (e.g. 2.5V ~ 4.2V)?

Thanks,

Zhihan

0 Nick Brylski over 4 years ago in reply to Zhihan Zhang

TI__Mastermind 19195 points

Hi Zhihan,

Yes best to start from 4.2 V (or whatever value cell manufacturer specifies, also you should discharge to the minimal voltage (as specified by the cell manufacturer). You can rerun to be safe but most likely will give same result.

Best regards,

Power management

Power management forum

BQ40Z50-R2: Chemistry ID