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Lithium‐rich manganese‐based layered oxides (LMLOs) are considered to be one type of the most promising materials for next‐generation cathodes of lithium batteries due to their distinctive anionic redox processes contributing ultrahigh capacity and energy density. Unfortunately, their practical applications are still plagued by several challenges such as undesirable interfacial reactions and structural evolution, as well as voltage hysteresis/recession, in which irreversible anionic redox behavior bears the brunt as the primacy factor. Undoubtedly, a deep understanding of anionic redox reaction mechanisms and irreversible behavior of oxygen species is crucial in order to provide essential guidance for modification strategies for LMLOs. In this paper, the fundamental understanding of intricate anionic redox reaction mechanisms from thermodynamics models to kinetic anionic redox reaction pathways is comprehensively reviewed, and the existing challenges of LMLOs related with irreversible oxygen reaction behavior are analyzed. Furthermore, numerous representative modification strategies for overcoming these challenges, coupled with their underlying mechanisms for regulating anionic redox reversibility are summarized. In addition, the aspects of multi‐scale structural modifications, integration of interdisciplinary technologies, and application in quasi‐/all‐solid‐state battery systems are given some emphasis in terms of further improvement of LMLOs‐based cathode materials for advanced lithium batteries‐based energy storage systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • PTFE-based dry-processed technology is used to prepare flexible Li 6 PS 5 Cl membrane and FeS 2 composite cathode membrane. • Due to the robust adhesion of PTFE, intimate contact is obtained at 100 MPa which is one-fifth of conventional pressure. • PTFE attaches the electrochemical sluggish products to an ion–electron conductive network to improve cyclic stability. • The flexible FeS 2 -ASSLBs exhibit excellent cyclic stability under the stack pressure of 100 MPa. All-solid-state lithium batteries (ASSLBs) are considered promising energy storage systems due to their high energy density and inherent safety. However, scalable fabrication of ASSLBs based on transition metal sulfide cathodes through the conventional powder cold-pressing method with ultrahigh stacking pressure remains challenging. This article elucidates a dry process methodology for preparing flexible and high-performance FeS 2 -based ASSLBs under low stack pressure by utilizing polytetrafluoroethylene (PTFE) binder. In this design, fibrous PTFE interweaves Li 6 PS 5 Cl particles and FeS 2 cathode components, forming flexible electrolyte and composite cathode membranes. Beneficial to the robust adhesion, the composite cathode and Li 6 PS 5 Cl membranes are tightly compacted under a low stacking pressure of 100 MPa which is a fifth of the conventional pressure. Moreover, the electrode/electrolyte interface can sustain adequate contact throughout electrochemical cycling. As expected, the FeS 2 -based ASSLBs exhibit outstanding rate performance and cyclic stability, contributing a reversible discharged capacity of 370.7 mAh g−1 at 0.3C after 200 cycles. More importantly, the meticulous dQ/dV analysis reveals that the three-dimensional PTFE binder effectively binds the discharge products with sluggish kinetics (Li 2 S and Fe) to the ion–electron conductive network in the composite cathode, thereby preventing the electrochemical inactivation of products and enhancing electrochemical performance. Furthermore, FeS 2 -based pouch-type cells are fabricated, demonstrating the potential of PTFE-based dry-process technology to scale up ASSLBs from laboratory-scale mold cells to factory-scale pouch cells. This feasible dry-processed technology provides valuable insights to advance the practical applications of ASSLBs. [ABSTRACT FROM AUTHOR]

Abstract Carbon anchored titanium carbonitride for supercapacitor electrode material was prepared by a direct semi-solid-sate carbonitridation method. The prepared sample is highly conductive and mesoporous (250 m2 g−1), enabling fast electron transfer and ion transport. As a result, a high capacitance of 360 F g−1 at 0.5 A g−1, and an impressive capacitance retention ratio 100Ag-1/1 A g−1 of 53%, as well as long cyclic capability (>10,000 cycles) can be obtained in 1 M H 2 SO 4. The thick electrode also presents a high area capacitance up to 1.77 F cm−2. A flexible H 2 SO 4 /PVA symmetric supercapacitor was fabricated to demonstrate its practicality. Remarkably, the supercapacitor presents high-rate performance (up to 25 kW kg−1) and long cyclic performance (>10,000 cycles), illustrating its potential application in flexible integrated energy storage devices. This work provides a novel insight into designing and preparing carbonitride based materials for high performance supercapacitor. Graphical abstract Image 1 Highlights • Carbon anchored titanium carbonitride is prepared by a bottom-up carbonitridation. • As the electrode material for ultrafast supercapacitor. • A high capacitance of 360 F g−1 at 0.5 A g−1, with a retention 100/1 A g−1 of 53%. • Thick electrode can present a high area capacitance up to 1.77 F cm−2. • Flexible solid state symmetric supercapacitor delivers 4.9 Wh kg−1 at 25,000 W kg−1. [ABSTRACT FROM AUTHOR]

N/P co-doped porous carbon is prepared from biomass (silkworm cocoon) and natural product (phytic acid) by an eco-friendly self-activation approach. Owing to the rational pore structure, and abundant pseudocapacitive active sites of heteroatom doping, the prepared Cheese-brick-like porous carbon presents outstanding performances. The optimized S2 sample delivers both high gravimetric capacitance and volumetric capacitance of 317 F g−1 (482 F cm−3) at 1 A g−1, and an impressive capacitance of 159 F g−1 (242 F cm−3) at a high current density of 50 A g−1 in 1 M H 2 SO 4. Also, the thick electrode (10 mg cm−2) can deliver a high areal capacitance up to 2.44 F cm−2 at 10 mA cm−2 and 1.29 F cm−2 at 500 mA cm−2. Additionally, the porous carbon based flexible symmetric supercapacitor (1.4 V) can deliver a remarkable 19.6 Wh kg−1 (29.8 Wh l−1) at 350 W kg−1, and 9.6 Wh kg−1 (14.6 Wh l−1) at 17500 W kg−1, respectively, as well as outstanding cyclic longevity (~98% capacitance retention after 10000 cycles). These attractive performances enable a wonderful potential of our porous carbon applied in supercapacitors for wearable electronics and other energy storage devices. • N/P co-doped porous carbon is prepared from silkworm cocoon and phytic acid. • As the electrode active material for high performance supercapacitor. • 317 F g−1 (482 F cm−3) at 1 A g−1, and 159 F g−1 (242 F cm−3) at 50 A g−1 • A high areal capacitance of 2.44 F cm−2 can be obtained. • Flexible supercapacitor delivers maximum 19.6 Wh kg−1 and 17.5 kw kg−1. [ABSTRACT FROM AUTHOR]