Microstructure, mechanical and functional properties of refill friction stir spot welds on multilayered aluminum foils for battery application

The production of batteries often involves the joining multilayered foils to a conductive tab. In present study, solid state spot welding method, refill friction stir (refill FSSW), was employed for commercially pure aluminum (CP–Al) 2024-T3 Al alloy sheets (tab). Defect-free welds with high lap shear strength (LSS) are obtained. stirred zone (SZ), 2024 is only found within shoulder region, which greatly refined due dynamic recrystallization. Unlike overlap joints in thicker sheets, thermo-mechanically affected also forms above SZ probe region. “Stop-action” experiments have been conducted describe joint formation. presence tabs resulted significant changes material follow behavior and formation microstructural zones not previously observed conventional FSSW sheets. Most failed pull-out mode during LSS test. cracks initiate at interface between upper sheet first layer then propagate upward circumferentially outside SZ. Welds produced by show low contact resistance. decomposition electrochemically active materials can be avoided maintaining minimum distance from spot-weld. flat appearance, mechanical properties, potential meet industry requirements imply that promising technique battery production.