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Battery performance is highly related to the intrinsic properties of battery materials. To develop commercial anode electrode materials for advanced sodium‐based batteries, it is crucial to understand whose fundamental issues including compositions and structure of the bulk and interface, dynamics and electrochemical reactions during cycling. The key for present and ongoing success of carbon‐based and sodium metal anode is to overcome an intrinsic challenge associated with transport and storage of ions and complicated interface activities, especially for the sodiation process with associated risk of dendrite. Advanced Nuclear Magnetic Resonance (NMR) technique has unique advantages in characterizing the local or microstructure of anode electrode materials and their interfacial evolutions down to the atomic level by a noninvasive and nondestructive manner. In this review, an overview is provided of the recent advances in understanding the fundamental issues of carbon based and sodium metal anode materials using advanced NMR approaches. Here, latest advancements of NMR are presented for applications in characterizing structures and dynamics of anode electrode material as well as their interfacial evolutions. Finally, the prospect and limitation of NMR techniques in batteries research will be highlighted, thereby paving the way for accelerating the development of next generation sodium batteries. [ABSTRACT FROM AUTHOR]

Ni‐rich layered oxides as the cathode materials of high‐energy‐density lithium‐ion batteries (LIBs) suffer from capacity decay and structural instability owing to oxygen loss during cycling. It is a huge challenge to prevent the oxygen loss of Ni‐rich cathode materials during long cycling. Here, a pre‐deoxidation of LiNi0.8Co0.1Mn0.1O2 (NCM811) single crystal materials is achieved by heat treatment at elevated temperatures in argon condition to form a stable surface with rock salt structure. The stable surface structure with oxygen vacancy defects successfully suppresses the harmful phase transitions of NCM811 and effectively improves the stability of the NCM811/electrolyte interface during cycling at a high cut‐off voltage. In addition, the intragranular structural evolution and cation mixing degree is inhibited to effectively suppress the intergranular cracking and particle pulverization of cathode during long cycling. The pre‐deoxidation of NCM811 exhibits 70.6% capacity retention after 1000 cycles at the current density of 0.5 C between 2.8 and 4.3 V, which is much larger than that of pristine NCM811 capacity retention of 27.3%. The strategy of pre‐deoxidation of Ni‐rich layered structure cathode to regulate the defect chemistry and surface structure provides a facile and effective way to achieve long cycling life high‐energy density LIBs. [ABSTRACT FROM AUTHOR]

Metastable multi‐element nanoalloys hold extensive potential for next‐generation batteries due to their distinct structures. However, it is difficult to obtain metastable nanoalloys through conventional equilibrium annealing. Herein, the rapid nanomanufacturing of metastable multi‐metallic nanoalloys is reported with single‐phase structure, ultrafine size distribution, and high‐density dispersion, realized by a novel nonequilibrium thermal shock (NTS) method. The NTS method, which features ultrafast heating/cooling rates and ultrashort treatment duration, can lead to the uniform mixing of different elements and the capture of the metastable state of multi‐element nanoalloys while preventing interparticle sintering/coarsening and phase separation. As a proof‐of‐concept demonstration, a metastable BiSnSb nanoalloy (M‐BiSnSb), prepared by the NTS method, exhibits rich lattice distortions and superior performance for potassium ion batteries (KIBs) compared with the stable BiSnSb (S‐BiSnSb) anode prepared by a typical equilibrium method. Additionally, in situ high‐temperature synchrotron X‐ray diffraction (SXRD) demonstrates the formation mechanism of M‐BiSnSb. Furthermore, in situ laboratory X‐ray diffraction (XRD) and molecular dynamics (MD) simulation systematically prove the alloying reaction mechanism and the structural advantages of the metastable nanoalloys in diffusion‐accelerating effect, respectively. This nonequilibrium nanomanufacturing strategy is expected to enable the rational and controllable synthesis of metastable nanomaterials for extensive electrochemical energy applications. [ABSTRACT FROM AUTHOR]

In article number 1805301, Yan‐Bing He and co‐workers report a low resistance integrated all‐solid‐state Li metal battery with excellent electrochemical performance. The battery structure applies polyethylene oxide with lithium bis(trifluoromethylsulphonyl)imide as both the binder of the cathode and matrix of the composite electrolyte embedded with Li7La3Zr2O12 nanowires. [ABSTRACT FROM AUTHOR]