BQ34110: LiFePo4 4S1P CEDV Profile

Hi,

Unfortunately, I do not have a generic .gg file for a LFP battery. The GPCCEDV tool will calculate parameters for the specific cells you are using.

Regards,

Evan

Hi Evan, I just need a LiFePo4 4S1P example .gg file. regardless of capacity. we just need a baseline to get going.

Hi, 

The GPCCEDV tool does not output a .gg file but list parameters that need to be changed.

Attached is the report from a LFP battery.

GPC CEDV tool, rev=60		
Configuration used in present fit		
ProcessingType=1		
NumCellSeries=1		
CellTermV=2000		
ChemType=4		
VoltageColumn=1				
CurrentColumn=2				
TemperatureColumn=3				
ElapsedTimeColumn=0		
FitMaxSOC%=12		
FitMinSOC%=6		
LearnSOC%=7		
		
CEDV parameters resulting from the fit. If EDVV bit is set to 1, EMF and EDVR0 have to be multiplied by the number of serial cells when written to data flash		
		
EMF	3114	
EDVC0	22	
EDVC1	0	
EDVR1	1739	
EDVR0	2343	
EDVT0	5341	
EDVTC	11	
VOC75	3316	
VOC50	3291	
VOC25	3237	
		
		
Recommended SOC deviation tolerance at EDV2 point is  < 5% for low temperature and <3% for room and high temperature		
		
Deviations for this set of parameters are given below for each file		
		
file	SOC error, %	pass
roomtemp_lowrate.csv	-1.13663407353065	1
roomtemp_highrate.csv	3.32962087261039	1
hightemp_lowrate.csv	-1.14727635247591	1
hightemp_highrate.csv	0.323503908513422	1
lowtemp_lowrate.csv	3.02668005024126	0
lowtemp_highrate.csv	-9.00627890912925	0
		
Warning: Deviation is above recommended level. Retry the fit with different settings, or proceed on  your own risk if the accuracy is acceptable for your application		
		

Regards,

Evan

hello, yes sorry, i was asking for the .gg file example for 4S1P LifePO4. we are having a problem that the capacity will shoot down to 0% once it discharges.

Hi,

I do not have .gg file example for 4S1P LFP application. Attached is a .gg file generated from the default .srec. However, I am not sure this will fix your issue, your issue sounds like it is related to not having a proper chemID match. Or not properly configured, I recommend getting a proper chemID match and then tuning your .gg file to your specific application. I cannot help with your SOC jump until a proper match is obtained.

bq35100defaultgg.gg.csv

Regards,

Evan

I have setup everything and double check, I reference the parameters of LifePo4 from the excel file from this thread 

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/1184703/bq34110-how-to-update-battery-from-default-to-lead-acid-for-bq34110

 After I discharge and recharge to 100% SOC, whenever I will discharge again it will automatically shoot down to 3%. Is there a bit or command on the gauge to enable proper learning capacity? 

I cannot use GPCCEDV tool as I cannot perform the proper GPC cycle since the calculated EDV measurements is wrong.

I tried and set the register to use the fixed EDV. Using fixed EDV corrected the SOC and other problem, so the root cause of my problem is that the calculated EDV measurements is wrong. I cannot seem to find this calculated EDV, I can only find the fixed EDV I set.

My question is how to make the IC reset or recompute the calculated EDV? How many discharge and charge cycle so the IC will recompute the EDV? Should the discharge and charge ACCUM register bit enabled or disabled? please list down the steps so the IC will recompute the EDV correctly. there is no chemistryID option in the BQStudio for BQ34110.

Hi,

This will not solve your issue since your gauge is not properly configured for the cells you are using.

Regards,

Evan