Ni-rich Li(NixCoyMnz)O2 (x ≥ 0.8)-layered oxide materials are highly promising as cathode materials for high-energy-density lithium-ion batteries in electric and hybrid vehicles. However, their tendency to undergo side reactions with electrolytes and their structural instability during cyclic lithiation/delithiation impairs their electrochemical cycling performance, posing challenges for large-scale applications. This paper explores the application of an Al2O3 coating using an atomic layer deposition (ALD) system on Ni-enriched Li(Ni0.8Co0.1Mn0.1)O2 (NCM811) cathode material. Characterization techniques, including X-ray diffraction, scanning electron microscopy, and transmission electron microscopy, were used to assess the impact of alumina coating on the morphology and crystal structure of NCM811. The results confirmed that an ultrathin Al2O3 coating was achieved without altering the microstructure and lattice structure of NCM811. The alumina-coated NCM811 exhibited improved cycling stability and capacity retention in the voltage range of 2.8–4.5 V at a 1 C rate. Specifically, the capacity retention of the modified NCM811 was 5%, 9.11%, and 11.28% higher than the pristine material at operating voltages of 4.3, 4.4, and 4.5 V, respectively. This enhanced performance is attributed to reduced electrode–electrolyte interaction, leading to fewer side reactions and improved structural stability. Thus, NCM811@Al2O3 with this coating process emerges as a highly attractive candidate for high-capacity lithium-ion battery cathode materials.
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Enhanced Electrochemical Performance of LiNi 0.8 Co 0.1 Mn 0.1 O 2 with SiO 2 Surface Coating Via Homogeneous Precipitation
Abstract Ni‐rich LiNi0.8Co0.1Mn0.1O2(NCM811) has been considered as a promising cathode material for high energy density lithium‐ion batteries. However, it experiences undesirable interfacial side‐reactions with the electrolyte, which lead to a rapid capacity decay. In this work, a homogeneous precipitation method is proposed for forming a uniform silicon dioxide (SiO2) coating on the NCM811 surface. The strong Si−O network provided a stable protective layer between the NCM811 active material and electrolyte to improve the electrochemical stability. As a result, the NCM811@SiO2cathode showed superior cycling stability (84.9 % after 100 cycles at 0.2 C) and rate capability (142.7 mA h g−1at 5 C) compared to the pristine NCM811 cathode (56.6 % after 100 cycles, 127.9 mA h g−1at 5 C). Moreover, the SiO2coating effectively suppressed voltage decay and pulverization of the NCM811 particles during long term cycling. This uniform coating technique offers a viable approach for stabilizing Ni‐rich cathode materials for high‐energy density lithium‐ion batteries.
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- Award ID(s):
- 1762602
- PAR ID:
- 10303570
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemElectroChem
- Volume:
- 8
- Issue:
- 22
- ISSN:
- 2196-0216
- Page Range / eLocation ID:
- p. 4321-4327
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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