電阻點焊是製程簡單且入門相對容易的焊接方式，但焊接原理需使用材料本身電阻，應用於電池連接時需考慮電阻所帶來的損耗。銅與鋁具有高導電性，但在使用焊接連接時會有介金屬產生，影響電性與機械性質。本研究使用鎳與鋅作為阻障層，阻障層可阻隔銅向鋁測的擴散，減少介金屬在點焊後熔核內部的生成量，使機械性質與電性提升。根據金相觀察與對介金屬進行定性，可確定影響熔核內部的介金屬為Al2Cu。在硬度測驗上，熔核內部硬度會隨阻障層厚度增加而降低，最終會趨向於母材，確認阻障層可減少介金屬生成量。而在拉伸試驗上，使用焊接電流1200 A可得到更高的強度，鎳阻障層會在厚度為15 μm時達到最大抗拉強度，鋅阻障層則會在厚度為20 μm時達到，而使用鎳作為阻障層比使用鋅具有更高的強度，最大抗拉強度為使用添加15 μm鎳與1200 A焊接電流時的45.5 MPa。本研究提出添加阻障層影響強度的兩種機制，一種為阻擋母材間的擴散減少介金屬生成使強度增加，另一種為吸收焊接機台提供的能量使焊接深度減少。電性量測部份，熔核內部與熔核至母材的電阻率具有與硬度相似的趨勢，最終都會趨近於母材，但在熔核內的銅鋁交界處，電阻率會受到缺陷影響而出現極值，說明影響電性的兩個因素為介金屬與缺陷。

When resistance spot welding is used to connect batteries, the loss caused by resistance must be considered. Copper and aluminum have high electrical conductivity, but when welded connections are used, dielectric metals will affect the electrical and mechanical properties. In this study, the use of nickel and zinc as barrier layers can block the diffusion of copper to aluminum, reduce the formation of intermetallic materials, and improve the mechanical and electrical properties. In the tensile test part, the maximum tensile strength is 45.5 MPa when adding 15 μm nickel and 1200 A welding current. This study proposes two mechanisms by which the barrier layer affects the strength. One is to block the diffusion between the base materials and reduce the formation of intermetallic materials to increase the strength. The other is to absorb the energy provided by the welding machine and reduce the welding depth. In the electrical measurement part, the resistivity inside the molten nugget and from the molten nugget to the base material will eventually approach the base material. However, at the junction of copper and aluminum in the molten nugget, the resistivity will be affected by defects and appear at an extreme value, indicating the impact The two factors of electrical properties are dielectric metal and defects.

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