Surface-Modified Quaternary Layered Ni-Rich Cathode Materials by Li₂ZrO₃ for Improved Electrochemical Performance for High-Power Li-Ion Batteries

Abstract

Quaternary Ni-rich layered cathodes are one of the most intriguing yet challenging next-generation cathode materials, and their high Ni content has made it difficult to obtain long-term cyclability. In this paper, we report the improved electrochemical performance of high-power long-life Ni-rich layered cathode materials (LiNi 0.90 Co 0.04 Mn 0.03 Al 0.03 O 2 , denoted NCMA), synthesized in a Couette−Taylor reactor, after depositing a homogeneous surface coating of Li 2 ZrO 3 (LZO). Morphological analyses revealed that the thickness of the LZO coating was approximately 2.5 nm and spread uniformly on the NCMA surface. X-ray photoelectron spectroscopy indicated that the content of Li residues on the surface had greatly decreased after coating with LZO. The electrochemical performance of the coated samples was greater than that of the bare NCMA; in particular, the 1 wt % LZOcoated cathode material had a capacity retention of 90.2% after 100 cycles at 1C (vs 74.6% for the bare NCMA). Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and the galvanostatic intermittent titration technique (GITT) indicated that the coating agent acted as a bridge that lowered the activation energy and polarization potential for a better Li + ion transport. The polarization potential also decreased significantly after coating with LZO, leading to improved electrochemical kinetics. Postmortem studies after long cycling confirmed that the LZO coating layer enhanced the structural stability of the cathode.

Polydopamine‐induced nano‐coating layer for high stability of nickel‐rich cathode in secondary batteries

“…Moreover, 3 wt% LNO‐LNCM cathode exhibited a higher capacity retention of 48.5% than pristine LNCM although it exhibits a lower capacity retention than the 1 wt% LNO‐LNCM cathode. These results suggest that 3 wt% or more of a thick coating layer interferes with Li + transport and leads to poor rate characteristics and cyclability 48 . As a result, the 1 wt% LNO‐coating layer can considerably improve the rate capability and cycle stability of the LNCM by suppressing the voltage loss, particularly under high‐rate conditions.…”

“…These results suggest that 3 wt% or more of a thick coating layer interferes with Li + transport and leads to poor rate characteristics and cyclability. 48 As a result, the 1 wt% LNO-coating layer can considerably improve the rate capability and cycle stability of the LNCM by suppressing the voltage loss, particularly under high-rate conditions. Moreover, based on the electrochemical data at room temperature ( 25 C), 1 wt% of the amount of LNO as a coating material for the LNCM is optimal.…”

In Situ Grown ZIF67 Particles on a Glass Fiber Separator: The Performance Booster and Anode Defender for Lithium–Sulfurized Polyacrylonitrile (SPAN) Batteries

“…The galvanostatic intermittent titration technique (GITT) was used at a rate of 0.1C within the voltage range of 1–3 V to determine the Li + diffusion coefficient. Assuming that the system obeyed Fick’s law (Li + ion movement in the electrode was driven by diffusion-type mass transport), the Li + ion diffusion coefficient was calculated using eq D normalL normali + = 4 π τ true( V normalm m normalm M normalm S true) 2 true( normalΔ E normals normalΔ E normalt true) 2 where V m is the molar volume of the active material (cm 3 mol –1 ), M m is the molecular weight of the material (g mol –1 ), m m is the mass of the active materials in the electrode (g), L is the thickness of the electrode (cm), A is the electrode/electrolyte contact area (cm 2 ), τ is the duration of the current pulse (s), Δ E s is the change in the steady-state voltage due to the current pulse, and Δ E t is the change in voltage during the constant current pulse.…”

Concerted Effect of Ion- and Electron-Conductive Additives on the Electrochemical and Thermal Performances of the LiNi0.8Co0.1Mn0.1O2 Cathode Material Synthesized by a Taylor-Flow Reactor for Lithium-Ion Batteries

“…39 Furthermore, the weaker intensity of the Ni 2+ oxidation state in the NCM811@Li-BTJ powder sample indicates a lower concentration of Ni in this valence state, confirming lower cation mixing and enhanced surface stability. 40,41 The XPS spectra of Co 2p display doublet peaks around 780.3 and 794.2 eV, referring to Co 2p 3/2 and Co 2p 1/2 , respectively, 42 as shown in Figure 4b. As illustrated in Figure 4c, the deconvoluted peaks in the Mn 2p spectra at about 643.4 and 646.5 eV confirm Mn 2p 3/2 and Mn 2p 1/2 splitting, respectively.…”