Advanced design of cathodes and interlayers for high‐performance lithium‐selenium batteries

Abstract

Lithium‐selenium (Li‐Se) batteries have attracted ever‐increasing attention owing to high volumetric capacity comparable to lithium‐sulfur batteries and excellent electronic conductivity of Se. However, unsatisfactory energy density and cycling life of Li‐Se batteries mainly caused by low utilization of Se and shuttle effect of polyselenides (PSes) seriously prevent their commercial applications. Herein, this work systematically reviews the recent advances of the state‐of‐the‐art cathodes and interlayers in high‐performance Li‐Se batteries. First, the fundamental chemistries of Li‐Se batteries are introduced in terms of various Se precursors and electrochemical behaviors. Second, the main strategies in cathodes and interlayers for addressing poor conductivity of Se and shuttle effects of PSes are summarized as three‐dimensional conductive skeletons for Se, physical confinement of Se, chemisorption and catalytic conversion of PSes, and free‐standing interlayers and interlayers on separators. Further, the synthesis strategies and enhanced electrochemical performance are specially exemplified to highlight the possible enlightenments for constructing advanced cathodes and interlayers. Finally, the future challenges and perspectives of advanced cathodes and interlayers in high‐performance Li‐Se batteries are briefly discussed.

An ultralight lithiophilic framework with Faraday-shielded cages for stable lithium metal anodes

“…Li-ion batteries have been commercially applied on a large scale, however, the specic energy of the Li-ion battery (250 W h kg −1 ) is failing to keep up with the continuously growing demands (500 W h kg −1 ) of the electric vehicle and electric device markets. [1][2][3][4][5][6] Naturally, world-wide attention was given to Li metal again for application in next-generation anodes, on account of the maximum theoretical specic capacity (3860 mA h g −1 ) and lowest potential (Li: −3.040 V vs. the standard hydrogen electrode). [1][2][3]7 Meanwhile, during the repeated plating/stripping processes, the uncontrollable generation of Li dendrites and dead Li hinders the practical application of Li metal anodes (LMAs), even though the technology was rst invented around 100 years ago.…”

Harnessing Plasma‐Assisted Doping Engineering to Stabilize Metallic Phase MoSe2for Fast and Durable Sodium‐Ion Storage

“…[3] Nonetheless, the application of thermodynamically stable semiconductor phase MoSe 2 (2H-MoSe 2 , trigonal prismatic D 3h ) in SIBs suffers some challenging issues, including low electronic conductivity originated from its semiconductive nature, severe volume variation, and continues Se species release arising from its conversion electrochemical reaction, hence inevitably leading to sluggish reaction kinetics and rapid capacity fading during sodiation/desodiation process. [4,5] Despite numerous strategies involving nanostructure and morphology configuration, [6,7] conductive substrate and protection layer modification, [8,9] as well as interlayer spacing expanding, have been proposed; [10] the inherent drawbacks still cannot be fully improved. Different from other kinds of sodium storage anode materials, the unique feature of polymorphism makes thermodynamically stable 2H-MoSe 2 capable of transforming to metallic phase (1T-MoSe 2 , octahedral Oh) to acquire manipulated crystal structure and electronic properties.…”

Functional MXene‐Based Materials for Next‐Generation Rechargeable Batteries

“…[ 74a ] The main challenge lies in their poor cyclability and low utilization efficiency of Se in practical application, which are mainly associated with the dissolution of the intermediate polyselenides in electrolytes and large volume expansion during the sodiation/desodiation process. [ 84 ] Confining the Se element into porous matrix could partly mitigate the issue. [ 85 ] In most of the cases, carbon materials are used as the host or substrate to host and promote dispersion of Se.…”