Internal heating of lithium-ion batteries at low temperatures based on electro-thermal modeling

Lithium-ion batteries (LIBs) are highly sensitive to operating temperature and experience particularly severe performance degradation at low temperature (here define as temperature below 0 °C). Preheating of LIBs represents an effective strategy to mitigate these adverse effects prior to operation under such conditions. Among various preheating techniques, the internal heating method has garnered increasing attention due to its advantages in temperature uniformity and operational simplicity. However, the application of excessively high current amplitudes during heating will induce capacity rapidly fade. To address this issue, this paper proposes a constrained pulse heating method that limits the current amplitude. Based on a thermal coupling simplified electrochemical model (TC-SEM), the criterion for preventing lithium plating is translated into current amplitude constraints across varying temperature and states of charge (SOC). Moreover, this study developed an experimental platform capable of delivering adjustable pulsed currents is constructed, incorporating these predefined current constraints to dynamically regulate the heating process and minimize degradation. Validation experiments demonstrate that no significant capacity degradation is observed following 100 heating cycles. In contrast, a control group subjected to heating with current amplitudes exceeding the prescribed heating current limits exhibited a capacity loss of approximately 2.1% after only 30 cycles.