BQ40Z50EVM-561: bq40z50evm,why are "Remaining Capacity" and "Full Charge Capacity" always at 100?

Naveesh Boppana

Part Number: BQ40Z50EVM-561
Other Parts Discussed in Thread: BQ40Z50-R2, BQ40Z50-R1

I am using Alium 5000 mah Lithium iron phosphate cylinder cell . 2 batteries in series . In BQ Studio I am using Chemistry with Chem id : 0461 . I am changing the design capacity values . I want to make sure I am using the proper chemical ID. I was able to charge and discharge earlier but now I cannot do anything . Is there a way to reset everything to default and start from scratch . I also need clear instructions on learning cycle and what some of the terms in Bq studio mean . The SOC always stays at 100 .

over 5 years ago

0 bdefar over 5 years ago

TI__Prodigy 680 points

Hi Naveesh,
Thank you for your interest in our products. A BMS expert has been assigned to your question.

0 Swaminathan Ramanathan75031 over 5 years ago

TI__Expert 6575 points

Hi Naveesh,
The easiest way to start from scratch is to download the default firmware to the device. The Latest firmware for bq40z50-R2 is available at: www.ti.com/.../toolssoftware
or for bq40z50-R1: www.ti.com/.../toolssoftware
The learning cycle instructions are identical to the instructions for a similar 2S device and can be found at www.ti.com/.../slua777.pdf
Regards,
Swami

0 Kevin Knicker over 5 years ago in reply to Swaminathan Ramanathan75031

Intellectual 920 points

Hi Swami,

Thanks for the suggestion. I was having the same issue. Loading the latest firmware and starting from scratch with the learning cycle has resolved the issue for me.

Best Regards,

Kevin

0 Naveesh Boppana over 5 years ago in reply to Swaminathan Ramanathan75031

Intellectual 430 points

Hi Swaminathan,

I am able to successfully perform the discharge part in learning cycle . But during the charge it says VOK should be set at start of charge and FC should be set at end of charge . And after leaving it for 5 hours (as its lifepo4) the rest flag never gets set . that is where I am stuck now . Do I also need to change any values other than capacity , taper current , term voltage . I am selecting the Da config in data flash as 0001 for 2 batteries in series . I also selected the chem id close to my battery from a different manufacturer will that effect even after i change the design capacity values . When it asks design voltage is it the maximum voltage or nominal voltage and how do I calculate cwh .

Thanks

0 Naveesh Boppana over 5 years ago in reply to Naveesh Boppana

Intellectual 430 points

And my guage is stuck at 100% and updates only after I send the reset command.

Power management

Power management forum

BQ40Z50EVM-561: bq40z50evm,why are "Remaining Capacity" and "Full Charge Capacity" always at 100?