Broad use of global or spatially averaging measurements over a cell to characterize highly localized Li plating phenomena in lithium-ion batteries during fast charging has created a disconnect between measurements and the underlying causes. Consequently, the field is missing a clear path to implementing fast charging as well as to expand into extreme fast charging (XFC). Aiming to bridge these gaps, we present a detailed look into local detection of Li plating and the consequent cycle life implications for electrodes and cells under XFC by utilizing electrochemistry and high-energy X-ray diffraction. Significant heterogeneity in Li plating during XFC results in accelerated and non-uniform cycle life losses, in contrast to the prevailing acceptance that C rate is correlated to Li plating for XFC. This behavior is triggered by local electrode heterogeneity, which has yet to be identified and is not apparent in volume-averaged quantifications. A better understanding of these multiscale local electrode heterogeneities is crucial for identifying pathways to enable XFC.

在电池上广泛使用全局或空间平均测量值来表征快速充电过程中锂离子电池中高度局部的Li镀层现象已导致测量值与根本原因之间的脱节。因此，该领域缺少实现快速充电以及扩展到超快速充电（XFC）的明确途径。为了弥合这些差距，我们通过电化学和高能X射线衍射对Li镀层的局部检测及其在XFC下对电极和电池的循环寿命的影响进行了详细介绍。XFC期间Li镀层中的大量异质性导致加速的和不均匀的循环寿命损失，这与公认的X速率C速率与Li镀层相关的接受相反。此行为由局部电极异质性触发，该异质性尚待确定，在体积平均定量中不明显。对这些多尺度局部电极异质性的更好理解对于确定启用XFC的途径至关重要。