Strictly speaking, lead-acid is only the starting power supply of the whole vehicle, not the power supply. Normal low-voltage power supply depends on the DCDC output of the vehicle and lead-acid power and DCDC are also used in conjunction with each other.
- Slow charging: Normal low-voltage power supply during slow charging is provided by DCDC or lead acid, and the 12V given by the charger is only a wake-up signal for BMS, but now there are 12V output of the charger with power output. Some OEMs will also switch the power supply during slow charging to the charger in the design of the whole vehicle. In fact, there are various schemes (there are many ways of power supply and wake-up for slow charging). The system design requirements of the main engine factory should be seen.
- Fast charging: Fast charging usually takes low-voltage electricity directly from the charging pile to activate and support the low voltage BMS.