Infiltrating Metal Adhesive Layer for Mechanically Integrated Dry Electrodes

Abstract

Dry‐processed high‐loading electrodes are essential for developing high‐energy‐density lithium‐ion batteries through solvent‐free manufacturing. However, most studies focus on material and structure of dry films, while adhesive layer required to laminate PTFE‐based dry films, which exhibit inherently low adhesion, to current collectors is typically fabricated using a wet‐process. Here, we introduce a sputter‐coated indium metal adhesive layer that enables an all‐solvent‐free dry electrode manufacturing process. During lamination, the indium layer infiltrates pores of graphite dry film and mechanically entangles with PTFE fibril, which strengthens interfacial contact between dry film and current collector. This electrode shows excellent capacity retention of 91.3% after 150 cycles at 0.33 C in half‐cells, while NCM622||graphite pouch‐cells (∼8 mAh cm −2 ) exhibit stable cycling for 150 cycles without delamination and dendrite growth. These results provide insights into infiltrating metal‐based adhesive layers for improving mechanical integrity and cycling stability of high‐loading dry electrodes.