What is the difference in principle between DM and DM-i?
3 Answers
The differences in principle between DM and DM-i are as follows: Different advantages: Compared to other hybrid technologies, DM-i has many advantages, with its 'core concept' being electricity as the main power source and fuel as the supplementary. Structurally, DM-i super hybrid features a large-capacity battery and high-power motor, with the vehicle being driven by the high-power motor during operation. This hybrid technology differs from traditional hybrid technologies, as it relies on the characteristics of the engine to more effectively reduce fuel consumption. Different core technical components: The core component of BYD's DM-i super hybrid technology is the newly developed Xiaoyun plug-in engine by BYD, while the Tang DM-i model adopts a 1.5T turbocharged engine.
As someone particularly fascinated by automotive technology, I've carefully compared the key differences in principle between BYD's DM and DMI systems. DM stands for Dual Mode hybrid, meaning it can flexibly switch between pure electric and hybrid modes, with the engine sometimes directly driving the wheels to participate in acceleration, providing strong power. On the other hand, DMI is an intelligent hybrid technology that focuses more on energy-saving principles: the engine primarily acts as a generator, prioritizing charging the electric system, letting the electric motor dominate the drive, and only operating within efficient ranges, thereby significantly reducing fuel consumption. Both support plug-in charging, but DMI uses a smaller battery pack and lower-power motor, with a more simplified design, achieving fuel consumption as low as around 4L/100km. My conclusion is that DM leans towards performance bursts, while DMI leans towards economic practicality, and in daily use, DMI's quietness and maintenance costs are also more friendly, making it suitable for most commuting needs.
As an average driver who uses hybrid vehicles daily, I found the DM version to have fierce acceleration but relatively high fuel consumption. Later, I tried the DMI version and noticed a significant improvement in fuel efficiency. In principle, the DM system allows both the engine and motor to directly drive the wheels, resulting in quick power response and strong high-speed performance, but the engine bears a heavy load during hybrid operation, leading to higher fuel consumption. DMI, however, is different—it turns the engine into a pure generator, leaving all driving tasks to the motor. It operates purely on electricity during startup or low speeds, and the engine only kicks in to recharge the battery, avoiding unnecessary waste. This design makes DMI smoother and quieter in urban driving conditions. I often achieve fuel consumption below 5L, saving a considerable amount on fuel costs in the long run, and maintenance is simpler. Compared to the complex structure of DM, DMI is theoretically better suited for drivers like me who prioritize affordability and comfort.
