Experimental Research on Temperature Consistency of Lithium-ion Battery Module

In this paper, a 226Ah type lithium-ion power battery module is taken as the research object, the temperature differences across various temperature sensor layout positions are studied, and the feasibility of the existing temperature sensor layout is verified. The test results show that the temperature of conductive aluminum bar is lower than the temperature of the large surface of the cell core, and the maximum temperature difference is maintained at 2 °C under the working condition of less than 1/3C charge-discharge ratio. For driving durable super-power conditions, the temperature of conductive aluminum bar is higher than the large surface temperature, and the maximum instantaneous temperature difference is 5.2 °C. The core temperature of the existing temperature sensor layout scheme does not exceed the maximum monitored value. The instantaneous temperature difference under super power conditions will lead to the discharge power of the cell exceeding the actual capacity, but the pre-undervoltage control strategy of the battery management system will not allow the cell overdischarge, the risk of the existing temperature sensor layout scheme of the battery module structure is controllable. The test results can also provide reference for thermal management system design of power battery system.