Testing method for a thermal contact

A testing method for a thermal contact, the method comprising:

• providing at least one battery cell of a battery module;
• providing at least one temperature sensor, the at least one temperature sensor being thermally coupled to a cell terminal of the at least one battery cell, an evaluation circuit and a plurality of wires electrically connecting the at least one temperature sensor to the evaluation circuit, wherein the at least one temperature sensor is physically biased toward the cell terminal of the at least one battery cell;
• measuring a temperature T1 of the at least one temperature sensor at a time point t1;
• heating the at least one temperature sensor for a predefined period of time (t2−t1) and/or (t3−t1);
• measuring a temperature T2 of the at least one temperature sensor at a time point t2 and/or a temperature T3 of the at least one temperature sensor at a time point t3;
• and
• determining, by the evaluation circuit, the thermal contact between the temperature sensor and the battery cell based on at least one temperature difference ΔT2,1=(T2−T1), ΔT3,1=(T3−T1, and ΔT3,2=(T3−T2),
• wherein measuring the temperature T1, the temperature T2 and the temperature T3 each includes receiving, by the evaluation circuit, one or more signals through one or more of the plurality of wires indicative of a temperature of the cell terminal of the at least one battery cell.