As we mentioned above, excessive discharge current can cause the battery to generate a large amount of heat, leading to oxidative decomposition of the electrolyte and reconstruction of the SEI, leading to delamination of the active material layer and causing a damage on the crystalline structure of NCM cathode.
The influence on battery from high charge and discharge rates are analyzed. High discharge rate behaves impact on both electrodes while charge mainly on anode. To date, the widespread utilization of lithium-ion batteries (LIBs) has created a pressing demand for fast-charging and high-power supply capabilities.
An overview of battery safety issues. Battery accidents, disasters, defects, and poor control systems (a) lead to mechanical, thermal abuse and/or electrical abuse (b, c), which can trigger side reactions in battery materials (d).
If the voltage of any battery cell cannot be effectively monitored by the management system, there will be risks of its overcharging. Since excess energy is stored into the battery, overcharging is very dangerous. Typically, all batteries are first charged to a specific SOC, but some batteries initially have higher SOC before charging.
The external environment (which controls the temperature, voltage, and electrochemical reactions) is the leading cause of internal disturbances in batteries . Thus, the environment in which the battery operates also plays a significant role in battery safety.
By analyzing the degradation of battery capacity, it is evident that, under consistent charging conditions, the rate of capacity decay in a battery is associated with the discharging rates utilized. Higher discharging rates result in accelerated capacity decay.