1. The Rise of Heat Pump Systems: A Key to EV Energy Efficiency
As electric vehicle battery energy density improvements approach a bottleneck, reducing overall energy consumption becomes critical to extending driving range. Heat pump air conditioning systems are emerging as a superior alternative to traditional PTC heating, especially in cold climates. Compared to PTC systems, heat pumps can significantly reduce energy consumption during winter, thereby increasing the vehicle's range.
However, widespread adoption in China has been slow due to several factors:
◆ Technical Challenges: Many domestic manufacturers struggle with low heating efficiency and capacity in low temperatures, as well as frost accumulation on evaporators.
◆ Cost Concerns: Heat pump systems typically add RMB 1,000–2,000 to the unit cost, which deters adoption in entry-level A00-class EVs.
◆ Policy Uncertainty: Some OEMs are awaiting national guidelines on refrigerant technologies. A few have begun exploring CO₂ (R744) as a refrigerant.
Tesla has demonstrated a strong case for heat pumps in its Model Y, utilizing motor waste heat recovery, motor stall heating, and combined waste heat from
electric a/c compressors and blowers. These innovations effectively resolve the limitations of low COP and insufficient heating in cold environments. Tesla’s design also prevents frosting of the external evaporator in ambient temperatures ranging from -5°C to 5°C.
| Category |
Brand |
Model/Series |
Heat Pump Configuration |
| Emerging Forces |
NIO |
Standard |
Standard |
| XPeng |
P5 |
Standard |
| Li Auto |
- |
- |
| Huawei |
- |
- |
| China Domestic Brands |
BYD |
E5 testing, Han |
Standard |
| Geely |
PMA platform |
Standard |
| SAIC |
- |
Standard |
| GAC |
AION LX |
|
| FAW |
- |
Standard |
| BAIC |
- |
Standard |
| Overseas Brands |
Volkswagen |
e-Golf |
Standard |
| Audi |
R8 e-tron, Q7 e-tron |
Standard |
| GM |
- |
- |
| Honda |
- |
- |
| Tesla |
Model 3, Model Y |
Standard |
Given these advancements, it is anticipated that more OEMs will adopt heat pump systems, especially for EVs priced above RMB 150,000, where the balance between cost and efficiency justifies the investment. With continued cost reduction, heat pumps may gradually penetrate the lower-priced A00-class segment.
Case Studies:
Audi e-tron: Combines a heat pump with a PTC and liquid thermal management to form a four-loop cooling architecture. Compared to pure PTC systems, the heat pump significantly boosts energy efficiency, with Audi reporting up to a 10% increase in range under Artemis and KUV real-world driving cycles.
Volkswagen ID.4: Uses the heat pump system to supplement traditional components, managing six different thermal circulation modes based on component temperature requirements. This strategy keeps the battery within its optimal temperature range, even in extreme conditions.
2. Integrated Thermal Management: Toward Platform-Level Optimization
Integration is becoming a dominant trend in EV thermal management. For example, the BYD Dolphin, built on the e-Platform 3.0, adopts a fully integrated refrigerant-based thermal management system. At its core is a heat pump compressor working in conjunction with a centralized control module that reallocates thermal energy to regulate cabin temperature, battery modules (Blade Battery), and power electronics.
BYD’s design simplifies refrigerant loops, dramatically reducing the complexity of coolant circuits while enhancing system efficiency and reliability.
Huawei has also entered the field with its TMS solution. Introduced in 2021, Huawei’s platform features the highest level of integration in the industry. It combines intelligent control and component-level innovations within a minimalistic architecture, aiming to improve EV driving range by up to 20%. The intelligent algorithm-driven approach also contributes to reduced energy losses and more responsive thermal regulation.
3. Enhancing Efficiency Under High-Power Charging Scenarios
The rise of high-voltage fast-charging technologies demands more
sophisticated battery thermal management solutions. On June 23, 2022, CATL unveiled its "Kirin Battery", which incorporates a new generation of thermal management. By optimizing water-cooling architecture, the system supports large current charging and discharging without compromising thermal safety. The Kirin system achieves a 50% improvement in thermal conductivity over conventional designs, resulting in significantly faster charging speeds and enhanced battery protection.
4. Eco-Friendly Refrigerants: Balancing Sustainability and Performance
Growing environmental awareness is also accelerating the transition to next-generation refrigerants:
R1234yf: This low-cost refrigerant is widely compatible with current heat pump components but remains under patent protection, limiting broader accessibility.
R744 (CO₂): CO₂ heat pump systems deliver superior heating performance at temperatures as low as -20°C. However, system-level implementation costs are high due to the need for reinforced compressors and high-pressure valves.
Example: Volkswagen ID.4 CROSS
The optional CO₂ heat pump system adds approximately RMB 9,000 to the vehicle’s cost. This includes a reinforced air compressor to handle the high operating pressures of CO₂ and specialized high-pressure valves to ensure long-term reliability. While CO₂ as a refrigerant is inexpensive, the supporting components drive up system costs. Nevertheless, this reflects automakers’ effort to balance long-term environmental sustainability with short-term economic constraints.
The future of EV thermal management lies in innovation, integration, and environmental consciousness. With advancing technologies and increasing regulatory clarity, heat pumps are poised to become the new standard for energy-efficient climate control. Integration at the platform level will further streamline system architectures, while new battery thermal strategies and refrigerant upgrades will enhance performance under both fast-charging and extreme temperature conditions. The next decade will witness a paradigm shift in how thermal systems are designed and implemented across the EV industry.
