Tool/software:
We are interested in the functionality and integration of the bq40z80 chip for balancing our batteries.
We have an evolutionary board with which we are experimenting to evaluate the best solution for us, and we came to the question of balancing the cells. We are looking at the documentation of the circuit, where internal or external passive balance with FET and a discharge resistor is proposed.
We want to ask if there is any limit on how small its value can be and for example, if it is 10 ohms, will this affect the voltage drop in the SOC when the balancing cycle is active. We hope that the algorithm compensates for the charge transfer during balancing.
Our second question stems from our first problem of fast cell balancing, as we would like to connect an external balancing circuit with active cell balance.
Will there be any effect on the SOC estimation algorithms and is it compatible if an external balance circuit manages the balance autonomously (balance module) and our bq40z80 circuit is for capacitance estimation without using its balance option. Will there be any effect on the SOC/SOH estimation when we have charge transfer between cells or will the impedance tracking continue to work.
As an example, we can point to a commercial product that overlaps with our criteria. But our question remains fundamental to the principle of operation of active balance schemes.
https://www.lithiumbatterypcb.com/product/10s-active-balancer-module-for-36v-li-ion-battery-equalizer/?srsltid=AfmBOoo9qDk2TDjjrnoxI_r0Rz6u05rywXlEGBswZu9bHf18MSG_N8Vl
