Heat exchanger element, heat exchanger unit with multiple heat exchanger elements, and a method for quality testing of a dielectrically insulating coating of the heat exchanger element

A system (1) for inductive energy transfer, in particular to a mobile application (100), comprising

• a stationary induction charging device (2, 2a) which has a stationary energy coil (3, 3a),
• a mobile induction charging device (2, 2b) which has a mobile energy coil (3, 3b),
• wherein in a charging operation of the system (1) one of the energy coils (3) generates an alternating magnetic field which for energy transfer induces a voltage for energy transfer in the other energy coil (3),
• wherein during charging operation the induction charging devices (2) are spaced apart from one another in a height direction (200),
• a positioning device (4) for detecting the positioning of the energy coils (3) relative to one another,
• wherein the positioning device (4) has at least four transmission coils (5) in one of the induction charging devices (2) and at least one receiver (6) in the other induction charging device (2),
• wherein four of the at least four transmission coils (5) are spaced apart from one another and in each case two of the transmission coils (5) are arranged opposite one another in such a way that the transmission coils (5) bound a virtual frame (50) which defines a virtual frame volume (51) which also extends in the height direction (200), wherein the energy coil (3) of the associated induction charging device (2) is arranged at least partially within the virtual frame volume (51),
• wherein the positioning device (4) is designed such that the transmission coils (5) in a positioning operation generate positioning fields (60) which can be distinguished from one another,
• wherein the at least one receiver (6) is designed such that it interacts in the positioning operation with the positioning fields (60) generated by means of the transmission coils (5) of the other induction charging device (2),
• wherein the positioning device (4) is designed such that in the positioning operation it identifies the ratio (62) between at least two of the positioning fields