Method and system for determining at least one electrical contact resistance

The invention relates to a method for determining at least one electrical contact resistance or at least one resistance value corresponding to the at least one electrical contact resistance between at least one pack electrical contact of a battery pack and at least one device electrical contact of an electrically driven working device or charging device, wherein the at least one pack power contact and the at least one device power contact touch each other and are loaded with a power current, and wherein the battery pack and the working device or the charging device are electrically connected by means of a data communication line for transmitting a data communication signal, wherein the method comprises determining at least one electrical contact resistance or at least one resistance value by comparing a signal voltage variable of the data communication line with an electrical voltage variable of the at least one packet electrical contact or the at least one device electrical contact with each other, wherein t