BQ34Z100-G1: Power management forum

Samruddhi Patil

Prodigy 210 points

Part Number: BQ34Z100-G1
Other Parts Discussed in Thread: BQSTUDIO, BQ34Z100

Dear sir,

I'm using BQ34z100-G1 for gauging.

My battery pack specs are :

13s13p NMC cells.(LGC 18650-M26 2600mAh/2500mAh)

Nominal voltage 46.8V

Charging volatge 54.6V

Charging current 10A

Max discharge current 45A

Capacity 33.8Ah

Shunt resistor value 1m-ohm.

Can you please help me setting the data flash parameters using bqstudio?

Scaling factor is 2X.

What should be the Taper current, Quit current, Qmax cell0, current at EOC etc?

Regards,

Samruddhi

over 5 years ago

0 Steven Yao over 5 years ago

TI__Genius 12215 points

Hi, Avi

Please refer to this document on how to configure bq34z100, the typical value for quit current and taper current is C/20, but the actual value need to consult cell vendor and considering your application request, Qmax Cell0 be updated in field use,

0 Samruddhi Patil over 5 years ago in reply to Steven Yao

Prodigy 210 points

Dear sir,

Thank you.

PFA

when i read the data through I2C using host controller, how to convert the all data values in each register to its respective unit?

example. voltage(),current(),temperature(),SoC(),etc.

like when i read the voltage register at location 0x08 it returns unsigned integer value, how to convert it into Volts?

same for current,temp,Soc,etc

is there any formula to convert this adc data into respective units?

Regards,

samruddhi

0 Steven Yao over 5 years ago in reply to Samruddhi Patil

TI__Genius 12215 points

Hi, Sam

The actual value is the hex reading from the target register

3e02, is 023e, which is 574 only, I think you may have not configured for multicell and not calibrated the device yet, also the voltage divider seems not very appropriate, typically, the dividend voltage should be at 60% to 90% of the full range of the ADC input at BAT pin

Current is the same

For, temperature, the read back value is a deci Keven temperature, which is with the unit of 0.1k

0 Samruddhi Patil over 5 years ago in reply to Steven Yao

Prodigy 210 points

Dear sir,

Okay, Thank you.

Yes device is not yet configured & calibrated for multicell, i was just checking the I2C communication.

Voltage divider is designed for the max. 60V input so resistors are 1M & 16.5K only.

Also while calibrating the device for current & capacity >29A, >29Ah resp.

if actual measured current is 4amps then to fool the gauge we have to enter the 2amps then calibrate so that scaling will be 2X.

right?

Then my design capacity, FCC, current thresholds etc all other parameters will be scaled down by 2.

Battery Specs: 13s13p

Nominal voltage 46.8V

Charging voltage 54.6V

Charging current 10A

Max discharge current 45A

Capacity 33.8Ah

scaling factor = 45A/29A =1.55 rounded to 2. same for capacity.

but for battery voltage = 54600/65535 =0.83 which is <1, so to match the scaling factor of 2X number of cells will also be divided by 2?

as battery voltage is <655535 but current & capacity is >29A/Ah.

Please guide me on the same.

Regards,

samruddhi

0 Kang Kang over 5 years ago in reply to Samruddhi Patil

TI__Mastermind 24870 points

Hello Samruddhi,

Your understanding is correct. Design capacity and all the charge current thresholds should be scaled down by 2 as well.