BQ34Z100-G1: learning cycle abort , charge not make 100%

Hey sangrok,

The issue you are facing is achieving valid charge termination which is why SOC is staying at 99% and not reaching 100%.

Conditions A & B look good, however condition C is where I think the problem is. In your log file, I see that the Charging Voltage is at 28800 mV (3600 mV per cell). However, the maximum voltage reached when charging is 27560 mV which is well below this value. Therefore, I would recommend either charging all the way to 28800 mV (this depends on what the data sheet says for your battery.) or adjusting the charging voltage parameters (Cell Charge Voltage T1-T2, Cell Charge Voltage T2-T3, and Cell Charge Voltage T3-T4) to a lower value. I will recommend following the datasheet for your battery on which solution to implement. 

Regards,

Nick Richards

OK, I'll change  cell charge voltages,  from 3600 to 3400 mV .  charge voltage will set 27000mV .

by the way.  Did I restart learning cycle? 

It takes long time... 

thank you. 

Yes, you will have to restart the learning cycle process.

Regards,

Nick Richards

I have more question.  

In order for the Register to be updated  (Update status, Ra table... etc),   during the learning cycle   should  be maintained  Flash update OK voltage (2800mV, *8 = 22.4V) ?      during  discharge batterry cycle -> Relax cycle .. 

The reason I'm asking is because it seems that register doesn't change below 21V.

 thank uyou.  

Hey sangrok,

I believe that register does not scale for the amount of cells you have. So the total voltage of your battery pack just needs to be above 2.8V.

Regards,

Nick Richards

Hi.  Nick . 

My question is, if I want to have a Qmax update and a Ra table update  on  the Discharge time and Relax time during the learning cycle,

Should be battery voltage  more than 22.4V (cell voltage 2800mV  ,Flash update OK voltage)  ? 

Since I used an 8S1P battery, I'm asking whether  I need to be at least 2800 mV * 8 cells = 22.4 V.  

From what I've observed, if it's under 20.8V (cell voltage 20.8/ 8 = 2600mV),  Qmax update and Ra table update don't seem to work.

thank you. 

Hey Sangrok,

Today is a holiday and no one is in the office. We will get back to you next week.

Regards,
Nick Richards

Hey Sangrok,

The entire voltage of the pack should be greater than 2800 mV, not each individual cell. Qmax and Ra table updates do not use the Flash Update OK Voltage parameter.

Regards,

Nick Richards

Hi.  Nick

I made Golden Image file .  and now Update status 0x06, 

but, I have more question . I don't understand below comment. 

How does it change  update status 0x0E,  ?    

What is  Last update status for Mass production  ?  0x06 or 0x 0E ?? 

[ When the packs are deployed in the end equipment and a field update occurs, the Update Status updates to 0x0E, which means that cell balancing has been enabled. If an Update Status of 0E is not obtained, the device can be charged to full, relaxed for 2 hours and then discharged to empty, at which point it should be 0E. ]