EV VS. ICE: TRANSMISSION TECHNOLOGY EXPLAINED
How Electric Vehicles Achieve Power Efficiently without Multi-Gear Systems
The primary difference between the transmissions in ICE vehicles and EVs is based on how power is generated and delivered:
EVs: Electric motors provide a broad and flat torque curve, which means they can deliver maximum power instantly and efficiently across a wide range of speeds. This eliminates the need for multiple gears, allowing for simpler and more efficient transmission systems.
ICE Vehicles: The combustion engine’s power output varies with RPM, so a multi-gear transmission is necessary to adjust the engine’s power to different driving conditions. Without gear changes, an ICE vehicle would either struggle at low speeds or over-rev at high speeds.
Benefits of EV Transmission Systems Over ICE
Simplicity: EVs use simpler single-speed transmissions, reducing the number of moving parts and the need for regular maintenance, such as gear oil changes or transmission repairs, which are common in ICE vehicles.
Efficiency: Electric motors are inherently more efficient than internal combustion engines, and the elimination of complex transmission systems further reduces energy losses. This leads to better energy usage, lower operational costs, and improved reliability.
Performance: With instant torque available from 0 RPM, EVs can offer rapid and smooth acceleration without gear changes, which enhances the driving experience.
Note: While most EVs use single-speed transmissions, multi-speed transmissions are integrated into high-performance electric vehicles to improve performance at very high speeds. For example, multi-speed transmissions can enhance efficiency at highway speeds by lowering the motor's RPM, which helps reduce energy consumption.
The fundamental difference between EV and ICE vehicle transmissions stems from the nature of their power sources. ICE vehicles rely on multi-gear transmissions to manage variable torque and power output, while EVs can use single-speed transmissions due to the instant, consistent torque generated by electric motors. This simplicity in EV transmission design leads to lower maintenance, smoother performance, and greater efficiency. As electric vehicle technology continues to evolve, we may see further innovations in transmission systems to meet the demands of high-performance and long-range EVs, but the overall trend remains in favor of simplicity and efficiency.
Source: https://afdc.energy.gov/vehicles/electric, https://www.fueleconomy.gov/feg/atv-ev.shtml