Can't identify Chemistry ID

bqEASY needs 4 OCV data points to do the chemistry matching. Looking at the log file, the last set of data point was corrupted and so the software failed to run the analysis.

bqEASY will discharge the battery to your min cell voltage level set at step 2A. What is your min cell voltage level set to? 2.5V? Are you using LiFePO4? You will need to raise the min cell voltage level a bit higher, we need to maintain communication in order to log the last OCV data point.

HI!

I used Lithium Polymer battery.

Please see our project file, where you will see the parameter.

2C_Dsg_Params.Min_Dsg_Cell_Vltg=2850

bqEVSW  does't  stop discharge battery on this level.

[Device]
Type=0750
Version=0160
DFI Filname=C:\Program Files\Texas Instruments\bq Evaluation Software\Plugins\Device Defaults\bq20z75_1_60.dfi
[Setup]
1A_Proj_Name.Project_Name=9300
1B_Load_DFI_File.DFI_Filename=C:\Program Files\Texas Instruments\bq Evaluation Software\Plugins\Device Defaults\bq20z75_1_60.dfi
[Project]
Name=9300
[Configuration]
2A_Cell_Char.Num_Series_Cells=2
2A_Cell_Char.Num_Parallel_Cells=1
2A_Cell_Char.Nom_Cell_Capacity=9300
2A_Cell_Char.Min_Cell_Vltg=2750
2H_Misc_Info.Is_Sys_Pres_Used?=True
2H_Misc_Info.CurrentSenseResistor=10
2H_Misc_Info.ThermistorConfig=2
2H_Misc_Info.Number_LEDs_Code=0
2H_Misc_Info.Mfr_Name=roki
2B_Chg_Params.Max_Chg_Cell_Vltg=4200
2B_Chg_Params.Min_Chg_Temperature=0
2B_Chg_Params.Max_Chg_Temperature=70
2B_Chg_Params.Chg_FET_Short_Threshold=25
2B_Chg_Params.Precharge_FET_Mode=1
2C_Dsg_Params.Min_Dsg_Cell_Vltg=2850
2C_Dsg_Params.Max_Dsg_Temperature=70
2C_Dsg_Params.Max_Steady_Dsg_Current=3500
2C_Dsg_Params.Peak_Dsg_Current=6500
2C_Dsg_Params.Dsg_FET_Short_Threshold=25
2D_Reserve_Capacity.Capacity=1
2D_Reserve_Capacity.Capacity_Units_mAh?=True
2E_Load_Characteristic.Is_Constant_Current?=False
2F_Secondary_Vltg_Protector.Is_Used_With_PFIN?=True
2G_Rem_Capacity_Method.Is_Constant_Load?=True
[Completion]
2A=False
4A=True
4B=True
2H=False
3F=True
4C=False
2B=False
2C=False
2D=False
2E=False
2F=False
2G=False
3A=False
3B=False
3C=False
3D=False
3E=False
5A=False
1B=False
5B=False
5C=False
1A=False

Earlier I had set the level of 3000mV and it didn't work.

Please give me a link to the latest Mathcad™ Chemistry Selection Tool or help me as soon as posible.

Regards

Wojtek

HI!

Do you have any news regarding my question?

Regards

Wojtek

hi,

when you tried the chemical ID ; did you disconnect the protection IC of your battery ?

To do the chemical identification, you must work on the cell and not on the battery.

I have not seen that problem before. The only thing I can think of is that voltage read by the IC is way off from what the actual voltage is? Have you calibrate the board before running chemistry selection test?

You can find the z75 product web page (http://focus.ti.com/docs/prod/folders/print/bq20z75.html), go to the Tools & Software section. You will find the mathcad tool download link there.

Victorien,

It's not necessary to disable the protection while running chemistry selection. You will discharge the battery to the min discharge voltage, which is still above your safety threshold.

When you run the chemistry selection, you have to use the EVM or your own pcb. So you'll need a battery pack to power up your board. (Unless you're working on a single-cell gas gauge, then you'll be working on a cell)