Battery pack low-temperature charging preheating strategy The required charging time of the battery pack depends on its state of charge before charging, the ambient temperature during charging, and the insulation effect of the battery pack.
Firstly, a topology structure for a low-temperature charging preheating system with an integrated dissipative balancing system was designed, which uses heating plates as both preheating elements and balancing resistors. This structure can enhance the balancing capability and achieve both preheating and balancing functions for the battery pack.
Many researchers have studied the low-temperature preheating technology of battery packs to improve the performance of power battery packs under low-temperature conditions. At present, the low-temperature preheating technology for batteries is mainly divided into internal heating technology and external heating technology [ 13 ].
Fast charging at lower temperatures (10-20 C) must be done very carefully, as the pressure within a cold cell will rise more quickly during charging, which can cause the cell to release gas through the cell's internal pressure vent (which shortens the life of the battery).
In the field of battery thermal management systems (BTMS), low-temperature heating is a core technology that cannot be ignored and is considered to be a technical challenge closely related to thermal safety.
Therefore, the heating target temperature that ensures the average temperature of the battery pack is above 0 °C during the charging process is not constant. It is necessary to study the battery low-temperature charging preheating strategy and adjust the battery preheating target temperature according to the actual situation.