How can I implement the temperature calibration?

If you are using a multicell impedance track gas gauge then you can use bqMTester hardware to calibrate during production. An accurate multimeter is the only additional equipment required.

https://estore.ti.com/ADVANCED-BQMTESTER-Texas-Instruments-Advanced-bqMTester-Multi-Station-Test-and-Program-Board-P2464.aspx

We try to maintain Temperature accuracy in +-1 deg C range. bqMTester has the capability to force recalibration if temperature drifts more than a pre configured value.

Skipping calibration will result in lesser accuracy as reported by gauge.

Hi Stones,

Which fuel gauge IC are you using?  If it is a single-cell fuel gauge then we do not recommend performing temperature calibration.  We calibrate it at the factory and it is close enough for good gauge performance in the field.  It may be off by a few degrees at room temperature, but we optimized the temperature calibration for accuracy at low temperature.  Low temperature measurement accuracy is more important than room and high temperature because the battery impedance changes quickly at low temperature.

Voltage calibration is also not so critical for the single-cell gauges.  Usually the voltage offset will be 0 after you calibrate unless your PCB has some offset.

Current calibration is more important, but if you don't perform it then you will also survive.  The current measurements may be slightly wrong, but the SOC will be correct after the gauge learns the battery.  This is because even though your mA readings might be wrong, the gauge will scale all mAh values that it learns with this wrong value.  Therefore your mAh/mWh readings from the gauge will learn incorrectly, but the SOC (relative ratio) will still be correct.

However, I still highly recommend that you at least do current calibration:

a) CC offset calibration (IC internal offset calibration) - does not require external equipment

b) CC board offset calibration (board offset) - does not require external equipment

c) Pack current calibration (sense resistor calibration) - requires external current meter for reference

Voltage and temperature calibration can be skipped.

We recommend that you put I2C test points on your system boards and then connect EV2300 to your system boards to perform calibration on the 20-30 samples with EVSW, then read the DataFlash values in the Calibration tab and record in a spreadsheet.  You can use File-> Export in the DataFlash tab to save a GG file for each calibrated system.  Then you can import into Excel and then you can average them and create a new GG file to import.

Hi,dMax

            I want to use bq27510-G1 to get remaining capacity from one Li+ cell.I think it is very complicated to use this chip.I don't know how to configure the bq27510 without EV2300.Which register I have to configure?

           which temperature do we have to calibrate?Is it the temperature of Li+ cell?  

Regards

Stones

First, I would recommend that you always use the latest version of our fuel gauge firmware.  That means in your case you should work with the bq27510-G2 (not G1).  It is a firmware upgrade so if your EVM or ICs have G1 firmware you can upgrade them to G2.

You are correct that there is some development effort required to customize the bq27510 to match your cell characteristics and your system requirements.  For starters, you can read the app notes and watch these videos:

http://focus.ti.com/general/docs/video/Portal.tsp?lang=en&entryid=0_ygafiu2n

http://focus.ti.com/general/docs/video/Portal.tsp?lang=en&entryid=0_bjd03jat

http://focus.ti.com/general/docs/video/Portal.tsp?lang=en&entryid=0_0kneyqg2