CCS/BQ40Z60: Why RSOC and ASOC sharply drop to 0?

Harry Zhang13

Part Number: BQ40Z60
Other Parts Discussed in Thread: BQSTUDIO

Tool/software: Code Composer Studio

Hi,

in my design, we have three series cells, our cuv protection is 2.1V. when discharging, why RSOC/ASOC will sharply drop to 0?

TimeStamp	Temperature	Int Temperature	Voltage	Current	Remaining Capacity	Full charge Capacity	Power	Cell 1 Voltage	Cell 2 Voltage	Cell 3 Voltage	Relative State of Charge	Absolute State of Charge	State of Health
2:06:10	34.2	20.9	8380	-3663	2940	10620	-3069	2394	2990	2987	28	29	100
2:06:13	34.3	20.9	8215	-3737	2890	10620	-3068	2226	2986	2982	28	28	100
2:06:16	32.3	20.9	8466	-1047	2870	10620	-63	2347	3089	3074	0	0	100

thanks,

harry

over 5 years ago

0 Kang Kang over 5 years ago

TI__Mastermind 24870 points

Hello Harry,

You will want to look at the bqStudio log using our EVM tool chain.

The RSOC will drop to zero any time you hit term voltage for the system.

0 Harry Zhang13 over 5 years ago in reply to Kang Kang

Intellectual 495 points

So when calculate/update RSOC, we didn't take every cell voltage into consideration? such as cell 1 2.2V, cell2 2.8V, cell3 2.7V, even if cell 1 will trigger CUV, the RSOC could be a high value(in our case 28%). and once cell1 trigger CUV, RSOC will change to 0?

0 Onyx Ahiakwo over 5 years ago in reply to Harry Zhang13

TI__Guru* 76230 points

it depends on what you set the termination to. You have the option to report 0% SOC based on the pack voltage or the individual cell voltagse. See page 79 of the TRM.

thanks

Onyx

Power management

Power management forum

CCS/BQ40Z60: Why RSOC and ASOC sharply drop to 0?