Study on the effect of tab cooling on the lithium-ion battery pack life cycle

Abstract

Electric vehicles are the future of mobility. Electric vehicles have batteries to store energy and the most common type of batteries used in electric vehicle’s battery packs are lithium-ion cells. These cells have very high energy density and dissi-pate heat during charging and discharging cycles. There is a need to have an efficient cooling system to dissipate this heat. Bigger-size batteries in four-wheelers use liquid cooling to ensure faster charging and longer battery life. Surface cooling and tab cooling are two popular types of liquid cooling systems for battery packs. Surface cooling is a preferred type of cooling system as it is less complex and cheaper, but it creates a temperature gradient inside the cell which is detrimental to cell life. This work proposes tab cooling as a solution to improve the life cycle of lithium-ion cells. Two sets of the battery pack, one with tab cooling and the other without a cooling system were tested under different conditions for multiple fast charging and discharging cycles until their initial capacity was reduced by 30%. The results show that with tab cooling the battery performed better and battery degradation was reduced.