Atomic-Scale Mechanisms of Sliding along an Interdiffused Li-Si-Cu Interface

We perform ab initio calculations On the shear deformation response of the interdiffused Li-Si-Cu phase structure existing between a lithiated Si electrode and a Cu current collector. We show that the formation of well-delineated and weakly bonded Si-Cu and Li-Cu crystalline atomic layers within this phase structure, facilitates interface sliding. HoweVer, sliditig can be terminated by the-formation of LiSi3 compounds across these atomic layers, which causes the abrupt capacity fade of the electrode aftet repeated cycling.