Cooling and heating technologies for battery thermal management

I. Extreme Temperature Challenges: A Common Industry Pain Point
As the core energy carriers for new energy vehicles, electrochemical energy storage systems, and aerospace equipment, lithium-ion batteries possess electrochemical properties that are highly sensitive to ambient temperature. Unlike traditional mechanical equipment, battery failure and degradation stem primarily from thermal imbalances and extreme thermal loads rather than mechanical wear.

In frigid environments (below -20°C), battery performance drops precipitously. Low temperatures increase internal ohmic and polarization impedances, severely impairing charge and discharge efficiency. During low-temperature charging, the negative electrode is prone to significant lithium plating and the formation of irreversible lithium dendrites; this not only reduces battery capacity and driving range by 30%–50% but also risks puncturing the separator, creating a short-circuit hazard. Conventional thermal management systems struggle to balance rapid heating in cold conditions with efficient heat dissipation in hot conditions, resulting in poor environmental adaptability.
II. Core Technical Bottlenecks in Dual-Mode (Hot/Cold) Thermal Management
First, maintaining temperature uniformity across the battery pack is a major challenge. Conventional external heating films and liquid cooling systems suffer from slow low-temperature heating and uneven heat distribution, leading to significant temperature disparities between individual cells. Localized overheating in hot environments and localized cold spots in cold environments exacerbate inconsistent cell degradation, ultimately causing premature decline in the battery pack's overall performance. Second, material and structural adaptability is limited. Standard thermal interface materials often exhibit low thermal conductivity at low temperatures and poor heat resistance at high temperatures, making it difficult to meet the requirements for stable, long-term operation across the extreme temperature range of -40°C to 50°C. Conventional structures relying solely on liquid or air cooling struggle to simultaneously satisfy the functional requirements for rapid heating and efficient heat dissipation.
III. TKT’s Integrated Heating and Cooling Solution for All-Climate Battery Thermal Management
To address the shortcomings of traditional external heating structures—such as slow temperature rise, uneven heating, and high energy consumption—TKT employs PTC heating technology, effectively meeting the preheating requirements for battery packs in low-temperature environments. Compared to standard heating films, this PTC heating module conforms closely to the cell layout, providing more uniform heating coverage and significantly faster thermal response. It enables rapid temperature rise even in extreme cold environments as low as -43°C, quickly bringing cell temperatures to the optimal 15°C–25°C operating range. This effectively resolves issues such as sluggish startup, power degradation, and charging limitations caused by low temperatures. Furthermore, the uniform surface heating method eliminates temperature disparities—such as localized hot or cold spots—and prevents irreversible damage (like anode lithium plating and dendrite growth) often caused by uneven temperatures during low-temperature charging, thereby greatly enhancing charge-discharge stability and safety in frigid conditions. Paired with a proprietary SOC (State of Charge) rapid calibration algorithm, the system accurately calibrates battery status within one minute and dynamically adjusts PTC heating power in real-time; this enables demand-based temperature control and intelligent energy conservation, minimizing wasted thermal energy.

For high-temperature operations, TKT utilizes a mature liquid cooling system—employing a 50/50 mixture of ethylene glycol and deionized water—to establish a comprehensive, closed-loop heat dissipation network for the battery pack. This overcomes the limitations of traditional air cooling, such as low efficiency, significant temperature gradients, and poor high-temperature performance. The 50:50 ethylene glycol-water solution is an optimal medium for power battery thermal management; it combines water’s high thermal conductivity—ensuring rapid heat transfer and dissipation during high-temperature operation—with the antifreeze properties of ethylene glycol, which prevents coolant freezing and pipeline blockages in cold environments. This allows a single system to serve as a universal thermal management solution across the entire operating temperature range.
The liquid cooling system features a layout that conforms closely to the battery cells, allowing it to instantly dissipate heat accumulated during high-rate charging/discharging and continuous operation. By rapidly suppressing temperature rises, it maintains the battery pack's operating temperature within a safe range, effectively eliminating risks associated with localized heat accumulation and thermal runaway. Moreover, closed-loop liquid cooling offers superior thermal stability and far greater temperature uniformity than air cooling; it strictly limits the temperature differential across the entire battery cell array, effectively mitigating inconsistent cell degradation under high-temperature conditions and slowing the overall decline in battery pack performance.
IV. Industrial Applications and Technological Outlook
Looking ahead, battery thermal management systems will evolve toward greater integration, intelligence, and energy efficiency. On one hand, the deep integration of vehicle-level and battery-level thermal management—leveraging waste heat recovery from the vehicle—will further reduce energy consumption for thermal regulation. On the other hand, the incorporation of AI-driven predictive control technologies will enable proactive temperature adjustment based on operating conditions and ambient temperatures, thereby enhancing the battery's adaptability across diverse environments.
Conclusion
Balancing low-temperature cold-start stability in frigid climates with operational safety in high-temperature environments is a core requirement for current battery thermal management technology. All-climate integrated thermal management systems overcome the limitations of traditional, single-mode thermal regulation. Through the synergistic innovation of internal self-heating technology, phase-change composite thermal management, extreme-temperature-resistant material systems, and intelligent control algorithms, these systems achieve adaptive thermal regulation across the battery's entire operating temperature range. This suite of technologies not only effectively addresses the performance degradation and safety risks associated with extreme environments but also significantly extends battery service life and reduces operation and maintenance costs, holding substantial value for industrial adoption and market application within the global new energy sector.