Experimental investigation on electro-thermal characteristics of the commercial Li-ion battery

As the most commonly used power battery in electric vehicles, lithium-ion battery is sensitive to the operation temperature. The performance and lifespan of lithium-ion battery are strongly dependent on its working temperature. Various thermal management systems have been developed to maintain batteries' operating temperature within an appropriate range. A properly designed thermal management system relies upon the understanding of battery's heat-generation characteristics and the temperature effect on its discharging performance. In this research, an experimental investigation is carried out to study the electro-thermal characteristics of the commercial prismatic ternary lithium-ion battery under three thermal conditions. Constant temperature condition is built to explore the effect of the operating temperature, while near-adiabatic condition and natural-convection condition are employed to study the heat-generation characteristics of lithium-ion battery. The results show that the effect of operating temperature on discharge performance becomes more pronounced as the discharge rate increases. It is found that the surface temperature decreases when the battery discharges at small rates within the capacity ranged from 17Ah to 27Ah, demonstrating that the reversible heat makes up a large proportion of battery heat generation.