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The electrochemical performance of cathode materials in Li‐ion batteries is reflected in macroscopic observables such as the capacity, the voltage, and the state of charge (SOC). However, the physical origin of performance parameters are atomistic processes that scale up to a macroscopic picture. Thus, revealing the function and failure of electrochemical devices requires a multiscale (and ‐time) approach using spectroscopic and microscopic techniques. In this work, we combine near‐edge X‐ray absorption fine structure spectroscopy (NEXAFS) to determine the chemical binding state of transition metals in LiNi0.6Co0.2Mn0.2O2 (NCM622), electrochemical strain microscopy to understand the Li‐ion mobility in such materials, and nanoindentation to relate the mechanical properties exhibited by the material to the chemical state and ion mobility. Strikingly, a clear correlation between the chemical binding, the mechanical properties, and the Li‐ion mobility is found. Thereby, the significant relation of chemo‐mechanical properties of NCM622 on a local and global scale is clearly demonstrated. [ABSTRACT FROM AUTHOR]

Direct recycling is a key technology for enabling a circular economy of spent lithium ion batteries (LIBs). For cathode active materials (CAMs), it is regarded as the tightest closed‐loop and most efficient approach among current recycling techniques as it simply proceeds via re‐lithiation and reconstruction of aged CAMs instead of separating them into elemental components. In this work, spent, i.e., morphologically and structurally decomposed CAM based on LiNi0.83Co0.12Mn0.05O2 (NCM‐831205) is restored by mimicking conditions of original CAM synthesis. After evaluating and optimizing the high‐temperature duration for CAM restoration and subsequent washing procedure, the recycled CAM is shown to maintain poly‐crystallinity and tap density, successfully recover specific surface area, lithium content, crystal structure in surface and bulk, while, however, only partly the original secondary particle size and shape. Though, comparable in initial 100 charge/discharge cycles with pristine CAM in lithium ion‐cells, the subsequent increase in resistance and capacity fading remains a challenge. High temperature during recycling can be regarded as a key challenge on material level, as it not only promotes detrimental surface carbonate species from residual carbon black but also enhances cation disorder and micro‐/nanoscopic porosity through oxygen release, likely in de‐lithiated, thus less thermally stable regions of cycled NCM. [ABSTRACT FROM AUTHOR]

Rechargeable lithium-ion batteries (LIBs) are critical for enabling sustainable energy storage. The capacity of cathode materials is a major limiting factor in the LIB performance, and doping has emerged as an effective strategy for enhancing the electrochemical properties of nickel-rich layered oxides such as NCM811. In this study, boron is homogeneously incorporated into the tetrahedral site of NCM811 through co-precipitation, leading to an inductive effect on transition metal (TM)-O-B bonds that delayed structural collapse and reduced oxygen release. Consequently, these changes culminate in an enhancement of cycling performance, translating to an initial specific capacity of 210 mAh g -1 and a 95.3% capacity retention after 100 cycles. These interesting findings deepen the understanding of boron doping and shed light on the design of better lithium cathode materials on an applicable scale., (© 2025 The Author(s). Small published by Wiley‐VCH GmbH.)