Abstract: Lithium/sulfur dioxide ( Li-SO₂) single cell usually presents as battery pack in practical application．Because the temperature caused by self-heating of the battery pack during discharging process is very high，specific thermal design is required． As one of the important thermodynamics parameters，specific heat capacity of battery is usually obtained by test． Based on preliminary studies，improvement is made in the following three aspects in this paper: transformer oil is employed for cooling，the test equipment of nylon material is designed for insulation，the thermal loss of the test devices is determined through brass test．Tests of specific heat capacity based on Li-SO₂ battery conducted before and after discharging are carried out．The results show that the scheme is feasible and reasonable; it has the features of high accuracy and easy implement．Specific heat capacity of the battery will change after discharging，which should be considered in thermal design．