Effect of High-Temperature Thermal Management on Degradation of Li-Ion Battery for Fast Charging

There is a growing demand for electric vehicles (EVs) and related technologies to promote low-carbon green growth. To meet this demand, charging technologies that can reduce charging times are becoming increasingly important. However, charging at high C-rates can lead to lithium plating or electrode damage because lithium ions cannot be inserted into the anode while being deposited on the surface, which could increase the irreversible capacity of the battery and pose safety risks. To address this issue, it is necessary to enhance the energy efficiency (EE) and safety of batteries while also suppressing battery deterioration by increasing the charge transfer and diffusion of lithium ions through thermal management of the battery prior to fast charging. This study analyzes the fast charge/discharge characteristics and deterioration factors of cylindrical batteries under different thermal management conditions to establish an optimal thermal management control strategy. The total discharge energy (DE) up to the end of life (EOL) of the battery increases by approximately 266% when the battery is fast charged at a minimum battery cell temperature of 54 °C. Optimal thermal management improves the lithium plating, internal resistance, and coulombic efficiency (CE) during fast charging. Thus, the battery can be safely and efficiently used for an extended period.