September 18, 2025
Purpose: Maintains the proper operating temperature range of the electric motor, power electronics, battery, and other components.
Main components managed:
Electric motor
Power electronics (inverter, DC-DC converter, onboard charger)
Traction battery pack
Cooling and heating methods:
Liquid cooling systems (most common in EVs)
Refrigerant-based cooling (sometimes integrated with the AC system)
Heat pump systems (in many modern EVs, used for both cooling and heating)
Importance: Directly affects performance, efficiency, safety, and battery life.
Purpose: The main energy storage system of the EV.
Composition:
Thousands of lithium-ion cells assembled into modules and packs
A Battery Management System (BMS) to monitor voltage, temperature, and state of health
Function: Supplies direct current (DC) electricity to the inverter.
Role in the drivetrain:
The inverter converts DC into alternating current (AC) for AC motors, or into controlled DC for brushless DC motors.
Powers the electric traction motor, which drives the wheels.
Secondary role: Provides energy for auxiliary systems such as lighting, infotainment, and climate control.
Summary:
The thermal system ensures that the battery and other critical components remain within safe and efficient temperature ranges, while the traction battery pack stores and delivers the electrical energy needed to power the traction motor and auxiliary systems.