Scenario-adaptive preheating path optimization for bidirectional pulses and lithium deposition prevention in high-SOC lithium-ion batteries

Abstract

Fast preheating of lithium-ion batteries at low temperatures while minimizing degradation remains a critical challenge in battery management. Bidirectional pulse heating has garnered interest among electric vehicle manufacturers due to its advantages in temperature uniformity, system simplicity, and compatibility with various battery shapes. However, its heating rate faces a sharp decline when heating high-SOC batteries due to the increased risk of lithium plating, rendering it unsuitable for emergency scenarios. This numerical study addresses this challenge by proposing a scenario-adaptive pulse preheating strategy, which removes the stringent requirement for equal charge throughput between charge and discharge pulses. This approach enables high heating rates while effectively mitigating lithium plating risks. An objective function is developed to identify the optimal heating pathway under various scenarios by balancing heating rate and SOC loss. Users can tailor the weighting factor to choose among heating-priority, energy saving-priority, or balanced modes. The simulation results reveal that the heating-priority mode achieves a remarkable heating rate of 5.77 °C/min even at 80 % SOC across a wide temperature range from −10 °C to 15 °C, nearly ten times faster than the energy saving-priority mode. This innovative strategy enhances the heating performance of bidirectional pulse and facilitates the promotion of electric vehicles in cold climates.