Non‐Uniform Distribution of Current in Plane of Large‐Area Lithium Electrodes

Abstract This work asserts that increasing the planar area of a lithium (Li) electrode is a challenge in view of ensuring a uniform plating and stripping and spatial uniformity for the state‐of‐health over the surface of lithium. A significant in‐plane heterogeneity is observed for the symmetric Li cells with the stack area in the range of 24 to 96 cm2. The cycling of the large‐area lithium electrodes is performed inside a dedicated home‐made electrochemical setup capable of incorporating electrodes of different sizes. The cycling data and post‐mortem analysis reveal a clear non‐uniformity in the distribution of current and aging for the lithium electrodes having a size larger than the coin‐cell and relevant to the commercial applications. It is shown that the inhomogeneous aging manifests mainly in the formation of dead Li film with a spatial variation in thickness and impedance over the surface of the Li electrode.