As I was trying to understand how BeagleBone Blue is handling battery management, I encountered a battery protection IC (S-8261).
- How does S8261 prevents overcharging and overdischarge? (ELI5)
- BQ29209 and MP2615 also have overcharge and discharge protection, why would you need an aditional IC (S8261)?
Bonus Question
Battery out (V_BATT) is directly connected to motor drivers (TB6612FNG).
- What's point of feeding the dc motors with a non-constant voltage(V_BATT)?
Best Answer
It looks like all three ICs complement each other. The MP2615 is CC-CV charger with overCHARGE limit at 10% of CC. The BQ29209 provides cell balancing and secondary overVOLTAGE protection. The S-8261 provides current limit during discharge, and overDISCHARGE protection, and the secondary overcharge (voltage cut-off at diminishing current) comes as a bonus.
What's the point of driving the motor directly from VBAT? Likely a better overall efficiency, to avoid losses in DC-DC conversion.