A shape memory alloy-inspired adaptive heat pipe-PCM thermal management system with dynamically regulated heat-transfer for lithium-ion batteries

To improve the thermal management performance of lithium-ion batteries, a shape-memory-alloy-inspired heat-pipe-phase-change-material (SMA-HP-PCM) system is proposed. By manually adjusting the extension of the heat pipe condenser to simulate the deployment process of SMA, the system can achieve adaptive heat dissipation under different operating conditions. Experiments were conducted to investigate the effects of ambient temperature, discharge rate, forced convection, and different paraffin-based PCMs on the thermal and electrochemical performance of battery. Compared with a conventional PCM system, the proposed configuration reduced the temperature difference within the PCM region by 15.98% during 0.8 C (3 A) discharge, while increasing discharge energy by 7.34%. When the ambient temperature decreased from 28 °C to 20 °C, the maximum temperature under 1.2 C (4 A) discharge decreased by 6.7 °C, accompanied by an 8.13% increase in discharge energy. Under 1.8 C (6 A) discharge, forced convection further reduced the battery temperature by 2.7 °C, demonstrating enhanced heat rejection capability. The thermophysical characteristics of different PCM considerably affect the overall system performance. The 23# PCM achieve effective early temperature suppression through earlier phase-change activation and heat pipe deployment, but its limited latent heat capacity weaken long-term thermal regulation, resulting in reduced discharge capability. In contrast, the 32# PCM provides sustained thermal buffering and maintained a favorable operating temperature, which alleviate polarization losses, delay voltage attenuation, and enhance discharge duration and energy output. The SMA-HP-PCM system provides an effective strategy for adaptive battery thermal management, simultaneously improving thermal safety and electrochemical performance.