Experimental investigation on the impact of the battery charging/discharging current ratio on the operating temperature and heat generation

This paper presents an experimental investigation on the Li-ion battery operating temperature and surface heat generation. Measurements are carried on the experimental laboratory test bench using a 60 Ah prismatic li-ion battery. A large data base of the battery local heat flux and temperature distributions in the three battery sides is obtained under various operating conditions. It shows that the reversible heat generation affects strongly the temperature profile in quasi-stationary regime. Moreover, the irreversible heat generation has a strong peak in SOCs values higher than 80%. A difference of 3°C was obtained between maximum battery shell temperature and minimum battery surface temperature. The electrodes temperature could be considered the maximum battery temperature and a main key in analyzing battery thermal behavior. For SOC ranging from 0% to 40%, the battery temperature decreases during charging phase and increases during discharging. For SOC ranging from 40% to 100%, it becomes constant during both the charging/discharging phases for the charge/discharge current ratio higher than 1.