Nowadays, new energy vehicles are everywhere, and the new energy power batteries generate continuous heat during operation. If the heat cannot be effectively managed, it can easily lead to a decrease in battery performance, and even cause safety issues such as fire or explosion. Therefore, thermal management systems have become an important component of new energy vehicles. Serpentine liquid cooling pipes (also known as serpentine tubes or serpentine cooling bands) are used for heat dissipation in cylindrical power batteries (such as 4680, 46120). The serpentine pipes are made by extruding aluminum tubes, and then folding, shaping, and welding them into shape. The principle is that the coolant flows through the internal fluid channel at a certain flow rate and pressure to maintain the working temperature of the battery relatively balanced. The serpentine pipe increases the contact area between the bent pipe and the cylindrical battery through lateral heat exchange to improve heat transfer efficiency, solving the problem of uneven heat dissipation at the top and bottom of the battery in liquid cooling at the bottom. In addition, the curvature of each serpentine pipe matches the cylindrical shape, increasing the contact area to improve heat conduction between the battery cells and the external environment, reducing thermal resistance. The surface insulation coating of the serpentine pipe is closely related to the battery heat dissipation and insulation performance, as well as the thickness of the coating on the serpentine and edges. Chusvision’s TS-C series spectroscopic confocal displacement sensor can achieve online measurement of insulation film thickness of serpentine water-cooled pipes.