How to effectively control internal temperature rise and thermal runaway risk in cylindrical lithium-ion batteries under high-rate charge/discharge conditions?
Publish Time: 2026-04-10
Cylindrical lithium-ion batteries are widely used in power batteries and energy storage systems due to their stable structure and mature technology. However, under high-rate charge/discharge conditions, the internal current density of the battery increases significantly, easily leading to accelerated temperature rise and the risk of thermal runaway.
1. Electrode Materials and Internal Resistance Control
Under high-rate operating conditions, battery heating mainly originates from internal resistance losses. Therefore, optimizing the positive and negative electrode materials and conductive network structure is crucial. By selecting highly conductive active materials and adding conductive agents, electron transport resistance can be reduced; simultaneously, optimizing the electrolyte formulation improves ionic conductivity and reduces polarization effects. Furthermore, controlling the electrode thickness and compaction density makes the electron and ion transport paths more uniform, which also helps reduce localized heating, reducing temperature rise at its source.
2. Winding Structure and Heat Distribution Optimization
Cylindrical batteries typically employ a winding structure, with tightly packed internal layers that easily form areas of concentrated heat. Optimizing winding tension and interlayer gap design can improve heat conduction paths in both the radial and axial directions. Simultaneously, using high thermal conductivity separators or introducing thermal channels into the structure helps to rapidly dissipate localized heat, preventing hotspot formation and reducing the probability of thermal runaway.
3. Casing Heat Dissipation and Safety Structure Design
The battery casing not only provides sealing and mechanical protection but also serves as a crucial heat dissipation path. Selecting a metal casing with good thermal conductivity and optimizing casing thickness and surface structure can improve heat transfer efficiency. Furthermore, installing a safety valve and explosion-proof structure at the top of the battery allows for timely release when internal pressure abnormally increases, preventing further thermal runaway and enhancing overall safety.
4. Thermal Management System and External Control
In battery pack applications, the external thermal management system is equally critical for temperature rise control. Methods such as air cooling, liquid cooling, or phase change materials can effectively remove heat generated during battery operation. In high-rate charge/discharge scenarios, real-time monitoring and dynamic adjustment of battery temperature can prevent continuous temperature increases. In addition, a reasonable layout of battery spacing and heat dissipation channels also helps improve overall heat dissipation efficiency.
5. Battery Management System and Intelligent Protection Mechanism
The battery management system plays a crucial role in preventing thermal runaway. Through real-time monitoring of voltage, current, and temperature, the system can promptly implement current limiting, power cut-off, or equalization control measures in abnormal situations to prevent localized overcharging or over-discharging. Simultaneously, by predicting battery state change trends through algorithms, it can provide early warnings of potential risks, achieving proactive safety management.
In summary, controlling temperature rise and thermal runaway in cylindrical lithium-ion batteries under high-rate conditions requires coordinated efforts from multiple levels, including material optimization, structural design, heat dissipation pathways, and intelligent management. Only through systematic design and refined control can battery safety and reliability be ensured while improving performance, meeting the demands of high-power applications.
