Copper bus bars insulated with heat shrink tubing, are widely used for power connections in electric vehicles, transformers, and panel boards. However, over the past several decades, epoxy powder and liquid coating methods have emerged as more efficient, durable, and environmentally friendly alternatives. This article will conduct a systematic comparative analysis of these three major technical routes from four dimensions: basic. Copper busbars generally need to choose heat shrinkable sleeves of different colors. The main function is to distinguish the positive and negative wiring and provide insulation protection.