High-Performance Amorphous Carbon Coated LiNi0.6Mn0.2Co0.2O2 Cathode Material with Improved Capacity Retention for Lithium-Ion Batteries

Abstract

Coating conducting polymers onto active cathode materials has been proven to mitigate issues at high current densities stemming from the limited conducting abilities of the metal-oxides. In the present study, a carbon coating was applied onto nickel-rich NMC622 via polymerisation of furfuryl alcohol, followed by calcination, for the first time. The formation of a uniform amorphous carbon layer was observed with scanning- and transmission-electron microscopy (SEM and TEM) and X-ray photoelectron spectroscopy (XPS). The stability of the coated active material was confirmed and the electrochemical behaviour as well as the cycling stability was evaluated. The impact of the heat treatment on the electrochemical performance was studied systematically and was shown to improve cycling and high current performance alike. In-depth investigations of polymer coated samples show that the improved performance can be correlated with the calcination temperatures. In particular, a heat treatment at 400 °C leads to enhanced reversibility and capacity retention even after 400 cycles. At 10C, the discharge capacity for carbon coated NMC increases by nearly 50% compared to uncoated samples. This study clearly shows for the first time the synergetic effects of a furfuryl polymer coating and subsequent calcination leading to improved electrochemical performance of nickel-rich NMC622.

A review on nickel-rich nickel–cobalt–manganese ternary cathode materials LiNi0.6Co0.2Mn0.2O2 for lithium-ion batteries: performance enhancement by modification

“…187 Considering that it is very challenging to establish a uniform carbon coating on the surface of NMC622 directly, it becomes interesting to achieve homogeneous surface coverage indirectly by the interaction of amorphous carbon-based materials in order to enhance the electrochemical properties. Kathribail et al 188 used the condensation reaction of furfuryl alcohol to form a poly-furfuryl coating on the surface of NMC622, which reduced the risk of oxidation of the carbon layer at high temperatures within air atmosphere. The homogeneous carbon-coated NMC622 with about 15 nm thickness obtained by roasting at 400 1C exhibited excellent electrochemical properties (Fig.…”

“…Kathribail et al . 188 used the condensation reaction of furfuryl alcohol to form a poly-furfuryl coating on the surface of NMC622, which reduced the risk of oxidation of the carbon layer at high temperatures within air atmosphere. The homogeneous carbon-coated NMC622 with about 15 nm thickness obtained by roasting at 400 °C exhibited excellent electrochemical properties (Fig.…”

Research Progress on Doping and Coating of High-Nickel Cathode Materials for Lithium-Ion Batteries

“…Surface coating can improve the stability of the surface structure of the material, promote the transfer of electrons on the surface of the material, and prolong the service life of the material. At present, commonly used coating materials include carbon materials (amorphous carbon [48][49][50], graphene [51][52][53], carbon nanotubes [54,55]), phosphate (Li3PO4 [56][57][58], LiFePO4 [59], MnPO4 [60]), fluoride (CaF2 [61], AlF3 [62], LiF [63]), oxides (LiBO3 [64], LiWO3 [65], Li2TiO3 [66], WO3 [67], SiO2 [68], Al2O3 [69], CeO2 [70]) etc.…”

Conductive carbon embedded beneath cathode active material for longevity of solid-state batteries

“…Although conductive carbon coating on the CAM surface is frequently used in conventional LIBs to improve the electronic conductivity of the cathode, 30,31 this approach is not suitable for ASSBs using sulfide SEs because the coated carbon must contact the SEs, which would lead to detrimental decomposition reactions (Fig. 1a).…”

“…18 Park et al demonstrated that the use of graphitized carbon with fewer functional groups in the composite cathode improved the reversible capacity and cycling stability. 29 Although conductive carbon coating on the CAM surface is frequently used in conventional LIBs to improve the electronic conductivity of the cathode, 30,31 this approach is not suitable for ASSBs using sulde SEs because the coated carbon must contact the SEs, which would lead to detrimental decomposition reactions (Fig. 1a).…”