In:
Journal of Materials Chemistry A, Royal Society of Chemistry (RSC), Vol. 10, No. 10 ( 2022), p. 5295-5304
Abstract:
The design of fast-charging, long-cycling, and high-voltage cathode materials remains challenging. Herein, through different strategies, Al and Nb/W are doped into the Co- and Li-sites in LiCoO 2 (LCO), respectively; according to density functional theory calculations, compared with the Co-site, doping at Li-site is thermodynamically unfavourable, which is primarily driven by the kinetic motif. We demonstrate that the Al-dopant at the Co-site inhibits the adverse phase transformation of LiCoO 2 under high voltage, while the Nb/W dopants intercalated within the Li-slab can serve as pillars that not only increase the interlayer spacing but also decrease the electronic coupling around Li + , thus increasing the population of highly active Li + and enabling fast Li + diffusion kinetics. Owing to the synergy effect from dual-site doping at both Co- and Li-sites, together with a discrete coating layer of niobium tungsten oxide (NWO) nanoparticles, the thus modified LiCoO 2 (denoted as ANW-LCO) cathode delivers highly stable and superior rate performance even under high voltage. Specifically, with a cut-off potential of 4.5 V, it displays a specific capacity of as high as 142.1 mA h g −1 at 15C and can maintain a reversible capacity of 85.3 mA h g −1 after 1000 cycles at 10C under 4.5 V, translating into a capacity retention of 60.4%. When evaluated at 4.6 V, it shows a capacity retention of as high as 77.5% after 100 cycles. When tested in all-solid-state lithium-ion batteries, it delivers a primal discharge specific capacity of 139 mA h g −1 and retains 71% of its capacity after 200 cycles. The full-cell also demonstrates outstanding cycling stability, with a capacity retention of 71% after 500 cycles at 2C.
Type of Medium:
Online Resource
ISSN:
2050-7488
,
2050-7496
Language:
English
Publisher:
Royal Society of Chemistry (RSC)
Publication Date:
2022
detail.hit.zdb_id:
2702232-8
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