Developments in Surface/Interface Engineering of Ni‐Rich Layered Cathode Materials

Abstract

Ni-rich layered cathodes with high energy densities reveal an enormous potential for lithium-ion batteries (LIBs), however, their poor stability and reliability have inhibited their application. To ensure their stability over extensive cycles at high voltage, surface/interface modifications are necessary to minimize the adverse reactions at the cathode-electrolyte interface (CEI), which is a critical factor impeding electrode performance. Therefore, this review provides a comprehensive discussion on the surface engineering of Ni-rich cathode materials for enhancing their lithium storage property. Based on the structural characteristics of the Ni-rich cathode, the major failure mechanisms of these structures during synthesis and operation are summarized. Then the existing surface modification techniques are discussed and compared. Recent breakthroughs in various surface coatings and modification strategies are categorized and their unique functionalities in structural protection and performance-enhancing are elaborated. Finally, the challenges and outlook on the Ni-rich cathode materials are also proposed.

A review of the degradation mechanisms of NCM cathodes and corresponding mitigation strategies

“…This calls for a more structured and evidence-based approach in searching for and optimizing the cycle life of NCM materials. Yet most of the existing review articles focus on synthesis [13][14][15][16], structural modification, doping, and coating [17][18][19][20], ageing [21][22][23][24], or other aspects [25][26][27][28][29][30][31] exclusively but not in sufficient context of each other. Moreover, although some highquality reviews have been made available before [23,[32][33][34][35][36], many fundamental studies released over the last years have substantially altered the view on redox activity, ageing, and decomposition of NCM cathodes [37][38][39][40], thus justifying an updated summary of the topic.…”

Outstanding Electrochemical Performance of Ni-Rich Concentration-Gradient Cathode Material LiNi0.9Co0.083Mn0.017O2 for Lithium-Ion Batteries

“…To improve the performance of Ni-rich ternary cathode materials, diverse approaches such as doping heterogeneous ions [20][21][22], surface coating [23][24][25], the construction of a single crystal phase [26][27][28], core/shell microstructure [29,30] and particles with concentrationgradient composition [31][32][33] have been adopted to inhibit the formation of microcracking. Among the preceding approaches, building particles with concentration-gradient composition is one of the most effective ways to improve the cyclability of electroactive materials.…”

Potassium doping towards enhanced Na-ion diffusivity in a fluorophosphate cathode for sodium-ion full cells

“…[1][2][3][4][5][6] To obtain high energy and power density in SIBs, a crucial task is the fabrication of advanced cathode materials with high redox potential and rapid Na + ion diffusivity. [7][8][9][10] Na 3 V 2 (PO 4 ) 2 O 2 F (NVPOF), featuring an open "Nasuper-ionic conductor (NASICON)" framework, has been considered a promising cathode material with a fascinating combination of thermal stability and electrochemical properties. [11][12][13][14] In NVPOF, two-dimensional (2D) interconnecting tunnels along the a-b plane provide robust pathways for the reversible intercalation/extraction of two Na + ions, thus achieving a high theoretical specic capacity of about 130 mA h g −1 in the material.…”