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Non‐equilibrium defects often dictate the macroscopic properties of materials. They largely define the reversibility and kinetics of processes in intercalation hosts in rechargeable batteries. Recently, imaging methods have demonstrated that transient dislocations briefly appear in intercalation hosts during ion diffusion. Despite new discoveries, the understanding of impact, formation and self‐healing mechanisms of transient defects, including and beyond dislocations, is lacking. Here, operando X‐ray Bragg Coherent Diffractive Imaging (BCDI) and diffraction peak analysis capture the stages of formation of a unique metastable domain boundary, defect self‐healing, and resolve the local impact of defects on ionic diffusion in NaxNi1−yMnyO2 intercalation hosts in a charging sodium‐ion battery. Results, applicable to a wide range of layered intercalation materials due to the shared nature of framework layers, elucidate new dynamics of transient defects and their connection to macroscopic properties, and suggest how to control the nanostructure dynamics. [ABSTRACT FROM AUTHOR]

[Display omitted] The Li-rich layered oxide is considered as one of the most promising cathode materials for high energy density batteries, due to its ultrahigh capacity derived from oxygen redox. Although incorporating over-stoichiometric Li into layered structure can generate Li 2 MnO 3 -like domain and enhance the oxygen redox activity thermodynamically, the fast and complete activation of the Li 2 MnO 3 -like domain remains challenging. Herein, we performed a systematic study on structural characteristics of Li-rich cathode materials to decipher the factors accounting for activation of oxygen redox. We reveal that the activation of Li-rich cathode materials is susceptible to local Co coordination environments. The Co ions can intrude into Li 2 MnO 3 -like domain and modulate the electronic structure, thereby facilitating the activation of Li-rich layered cathode materials upon first charging, leading to higher reversible capacity. In contrast, Li 2 MnO 3 -like domain hardly contains any Ni ions which contribute little to the activation process. The optimum composition design of this class of materials is discussed and we demonstrate a small amount of Co/Mn exchange in Li 2 MnO 3 -like domain can significantly promote the oxygen redox activation. Our findings highlight the vital role of Co ions in the activation of oxygen redox Li-rich layered cathode materials and provide new insights into the pathway toward achieving high-capacity Li-rich layered cathode materials. [ABSTRACT FROM AUTHOR]

Despite their safe and cost‐effective merits, the cycling durability of aqueous zinc–organic batteries is hindered by cathode dissolution and low coulombic efficiency of Zn metal anodes. Herein, a Zn metal‐free all‐organic zinc‐ion battery (ZIB) is proposed by using quinoxalino[2,3‐i]diquinoxalino[2′,3′:6,7]quinoxalino[2,3‐a:2,3‐c] phenazine (QDPA) cathode coupled with a 1,4,5,8‐Naphthalenetetracarboxylic diimide (NPI) anode, rendering excellent electrochemical reversibility with high utilization. Based on the molecular architecture strategy, a QDPA cathode with an enlarged aromatic ring system is designed and synthesized, which not only effectively inhibits structural collapse during cycling but also enhances the working voltage without lowering the active group ratio. Moreover, theoretical calculations and experimental results confirm the rapid H+ storage mechanism in the CN active sites of QDPA, affording ultra‐fast electrochemical kinetics. Thus, it delivers a negligible capacity decay of 0.002% up to 13 000 cycles at 20 A g−1. Moreover, the QDPA//NPI all‐organic aqueous ZIB with a high energy density of 43.1 Wh kg−1 is demonstrated to be easily disassembled and recycled by the incineration treatment after battery failure, ensuring outstanding environmental sustainability. [ABSTRACT FROM AUTHOR]

Zn−I2 batteries stand out in the family of aqueous Zn‐metal batteries (AZMBs) due to their low‐cost and immanent safety. However, Zn dendrite growth, polyiodide shuttle effect and sluggish I2 redox kinetics result in dramatically capacity decay of Zn−I2 batteries. Herein, a Janus separator composed of functional layers on anode/cathode sides is designed to resolve these issues simultaneously. The cathode layer of Fe nanoparticles‐decorated single‐wall carbon nanotubes can effectively anchor polyiodide and catalyze the redox kinetics of iodine species, while the anode layer of cation exchange resin rich in −SO3− groups is beneficial to attract Zn2+ ions and repel detrimental SO42−/polyiodide, improving the stability of cathode/anode interfaces synergistically. Consequently, the Janus separator endows outstanding cycling stability of symmetrical cells and high‐areal‐capacity Zn−I2 batteries with a lifespan over 2500 h and a high‐areal capacity of 3.6 mAh cm−2. [ABSTRACT FROM AUTHOR]

Zn−I2 batteries stand out in the family of aqueous Zn‐metal batteries (AZMBs) due to their low‐cost and immanent safety. However, Zn dendrite growth, polyiodide shuttle effect and sluggish I2 redox kinetics result in dramatically capacity decay of Zn−I2 batteries. Herein, a Janus separator composed of functional layers on anode/cathode sides is designed to resolve these issues simultaneously. The cathode layer of Fe nanoparticles‐decorated single‐wall carbon nanotubes can effectively anchor polyiodide and catalyze the redox kinetics of iodine species, while the anode layer of cation exchange resin rich in −SO3− groups is beneficial to attract Zn2+ ions and repel detrimental SO42−/polyiodide, improving the stability of cathode/anode interfaces synergistically. Consequently, the Janus separator endows outstanding cycling stability of symmetrical cells and high‐areal‐capacity Zn−I2 batteries with a lifespan over 2500 h and a high‐areal capacity of 3.6 mAh cm−2. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable Zn metal batteries (AZMBs) have attracted widespread attention due to their intrinsic high volumetric capacity and low cost. However, the unstable Zn/electrolyte interface causes Zn dendrite growth and side reactions, resulting in poor Coulombic efficiency and unsatisfactory lifespan. Herein, a SiO2 reinforced‐sodium alginate (SA) hybrid film is designed to regulate solid–liquid interaction energy and spatial distribution of all species in the electric double layer (EDL) near the Zn electrode. The unique interfacial layer gives rise to a uniform distribution of Zn2+ in the Helmholtz layer through solvation sheath modulation. Moreover, theoretical calculations show that the SO42− anions and free‐water are substantially reduced in the Helmholtz layer, effectively suppressing hydrogen evolution reaction and formation of by‐products through strong charge repulsion and hydrogen bond fixing of free‐water. The reconfigured EDL not only ensures homogenous and fast Zn2+ transport kinetics for dendrite‐free Zn deposition, but also eliminates interface parasitic side reactions. The Zn@SiO2‐SA electrode enables excellent cycling stability of symmetrical cells and high‐loading full AZMBs with a lifespan over 3000 h and an areal capacity of 2.05 mAh cm−2, thus laying a solid basis for realizing practical AZMBs. [ABSTRACT FROM AUTHOR]

[Display omitted] Classical layered transition metal oxides have remained the preferred cathode materials for commercial lithium-ion batteries. Variation in the transition metal composition and local ordering can greatly affect the structure stability. In classical layered cathodes, high concentrations of electrochemically inert Mn elements usually act as a pillar to stabilize the structure. When excess amount of Li and Mn are present in the layered structure, the capacity of the Li-rich layered oxide (molar ratio of lithium over transition metal is larger than one by design) can exceed that expected from transition metal redox. However, the over lithiation in the classical layered structure results in safety issues, which remains challenging for the commercialization of Li-rich layered oxides. To characterize the safety performance of a series of Li-rich layered cathodes, we utilize differential scanning calorimeter and thermal gravimetric analysis; this is coupled with local structural changes using in situ temperature dependent synchrotron X-ray diffraction and X-ray adsorption spectroscopy. These methods demonstrate that the gradual decrease of the Mn–M (M = Ni, Co, Mn and Li) coordination number directly reduces structural stability and accelerates oxygen release. For safety characterization tests in practice, we evaluate the thermal runaway process through accelerating rate calorimeter in 1.0 Ah pouch cells to confirm this trend. Using the insights obtained in this work, we design a polymorphic composition to improve the thermal stability of Li-rich layered cathode material, which outperforms Ni-rich layered oxides in terms of both electrochemical and safety performances. [ABSTRACT FROM AUTHOR]

Batteries, diffraction, operando, single-particles, sodium-ions Disorder Dynamics in Battery Nanoparticles During Phase Transitions Revealed by Operando Single-Particle Diffraction (Adv. Keywords: batteries; diffraction; operando; single-particles; sodium-ions EN batteries diffraction operando single-particles sodium-ions 1 1 1 03/28/22 20220324 NES 220324 B Sodium-Ion Batteries b In article number 2103521, Jason J. Huang and co-workers use operando single particle X-ray diffraction to probe disorder dynamics in individual cathode particles of Nax[Ni SB 1/3 sb Mn SB 2/3 sb ]O SB 2 sb , an archetypal cathode material for sodium-ion batteries. [Extracted from the article]