Electro-Thermal Influence of Interconnection Methods for PTC-Elements on Ceramic Substrates

Positive temperature coefficient (short: PTC) resistors are essential for self-regulating heating systems in electric vehicles. Their thermal connection to an electrically insulating substrate plays a critical role. Typically, PTC elements are glued to ceramic bodies, but these adhesive connections limit the operational temperature range and can lead to uneven current flow. This study investigates two alternative interconnection methods on ceramic substrates like sintering and soldering and comparing their electrothermal effects. Using infrared thermography and impedance spectroscopy to analyze thermos-electrical behavior, and performance under warming and cooling conditions. The findings provide valuable insights for optimizing the thermal management and reliability of PTC-based heater-systems.