Design of battery connection using copper conductor with tin and silver coating

This paper discusses the design of lithium ion battery connection for electric vehicle. The copper is chosen as main material of battery connection because of its high conductivity and high mechanical strength. For reducing electrical contact resistance, the author proposes two methods. The first method is increase of contact pressure at the junction. The second method is the addition of plating material with higher conductivity and wider surface area. Silver is chosen as copper plating material in the battery connection design because its high conductivity. In addition, tin is also chosen as copper plating material in the battery connection design because its high surface contact area. The designed battery connections were examined in three steps: no load test, DC loading test, and AC loading test. The examined parameters were contact resistance and power losses on the copper junction. The effect of contact pressure and plating material on the electrical contact resistance and power losses of copper junction of battery connection was investigated. The results showed that the sample of the copper junction with silver coating had the smallest contact resistance and power losses. The increase of the contact pressure reduced the contact resistance and power losses of the copper junction on three samples. The 8.4 MPa contact pressure gave the smallest contact resistance and power losses.