Surface‐Modified Ni‐Rich Layered Oxide Cathode Via Thermal Treatment of Poly(Vinylidene Fluoride) for Lithium‐Ion Batteries

Abstract

Combination of poly(vinylidene fluoride) (PVDF) with Ni-rich layered cathode material create artificial cathode-electrolyte interphases by thermal decomposition of PVDF and residual Li + species. The pressure of the cell cycled with PVDF-treated cathode materials is markedly decreased, since the thermal treatment with PVDF selectively reduces the amounts of Li + species. The cycling performance is improved compared to nontreated Ni-rich layered cathodes because the artificial cathode-electrolyte interphases effectively suppress the electrolyte decomposition as determined by systematic characterization of particle hardness, surface morphology, and electrochemical impedance spectroscopy. Additional high temperature storage tests performed with 3450-dimensioned pouch cells indicate much improved recovery rates, as well as smaller open circuit voltage drops, smaller increases in internal resistance, and less swelling for cells cycled with the PVDF-treated Ni-rich layered cathode than with a nontreated Ni-rich layered cathode.

Edge-Protected Ni-Enriched LiNixCoyMnzO2 Cathode Materials by Interface Modification with a Si- and F-Functionalized Surface Modifier

“…Among the many potential cathode material candidates, Ni-enriched layered oxides (LiNi x Co y Mn z O 2 , Ni-enriched LN) have received considerable attention in recent decades. Ni-enriched LN and LCO cathode materials have an identical layered structure, except that the Co site is partially replaced with the Ni element in the LiNi x Co y Mn z O 2 (LN) cathode material. , Because the oxidation potential is lower for Ni than for Co, the LN cathode material can deliver a higher specific capacity. − In addition, increasing the Ni composition in the LN cathode efficiently increases the specific capacity of the cathode. − Therefore, research on Ni-enriched LN cathode materials (with Ni compositions greater than 60%) has been rapidly expanding.…”

Reverse electrodialysis for emerging applications

“…However, research on the nonsolid-state power source still remains insufficient, and inevitably induces electronic-biosystem contact. While conventional electrical batteries supply electrical energy by driving electron movement, [47][48][49][50] they cannot be directly applied to ionic systems due to them functioning in completely separate media thus unable to directly communicate with each other. By the way, RED, electrodeless ionic power source as a biocompatible and biodegradable material, enable to communicate with biological system, then shed light on futuristic biological and clinical implant system.…”

Pillar Effect in Ni‐rich Cathode of Li‐Ion Battery by NH3 Thermal Treatment

“…Diverse bulk substitution strategies and surface treatments have been suggested to impede the structural degradation and capacity fading 8–10 . For instance, substitution with various transition metals ( e.g ., Al, Zr, Ta, etc.)…”