Enhanced Electrochemical Properties of LiNi_0.8Co_0.1Mn_0.1O₂ Cathode Materials Modified with Lithium‐Ion Conductive Coating LiNbO₃

Abstract

As a promising cathode material for lithium‐ion batteries, nitrogen‐rich LiNi0.8Co0.1Mn0.1O2 (NCM811) attracts great attention for its high specific capacity, but the rapid capacity decline of NCM811 in the process of charge/discharge restricts its extensive application. To alleviate the capacity decline for NCM811, a solid electrolyte LiNbO3 material with lithium‐ion diffusion and electron conduction activity was successfully coated on the surface of NCM811 by adopting a simple two‐step method, and the amount of the LiNbO3 coating layer was investigated. Powder X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, and X‐ray photoelectron spectroscopy were used to characterize the as‐prepared cathode materials. The experimental results revealed that the LiNbO3 played a role in reducing surface residual alkalis and protecting NCM811 from erosion by electrolyte. When the weight ratio of LiNbO3 and NCM811 was 1 %, the corresponding 1 wt % LNO@NCM material displayed the best cycle performance and rate capability, whose capacity retention at 1 C after 200 cycles, and discharge capacity at 10 C are 90.1 % and 122.7 mAh g−1, respectively.

Effect of FEC electrolyte additive on the electrochemical performance of nickel-rich NCM ternary cathode

“…Selected fast Fourier transform (FFT) patterns of the region I confirm the formation of a typical layered structure, consistent with previous reports. 24,25 For NCM90 cycled in BE, two more phases can be identified from Fig. 2(a), an amorphous phase layer with a width of ~3.2 nm forms near the interface, (from the blue dotted line to the surface), followed by a double-layer structure of rock salt phase (~8.1 nm, between red and blue dotted line) between the amorphous layer and the bulk region.…”

Interface Engineering of All‐Solid‐State Batteries Based on Inorganic Solid Electrolytes

“…Whether LiNbO 3 coating layer is crystalline or amorphous is almost affected by the synthetic methods and heat treatment temperature in the preparation process. [90][91][92][93][94][95][96] Highly crystalline LiNbO 3 coating can be obtained by solid-state reaction method or heat treatment at higher temperature based on the solution method. [97][98][99] However, compared to crystalline LiNbO 3 , amorphous LiNbO 3 coating not only can deform elastically to avoid cracking during strain generation due to lower stiffness, but also has higher ionic conductivity, which makes CAMs with amorphous LiNbO 3 coating present better electrochemical performance.…”

Fast‐Charging Solid‐State Lithium Metal Batteries: A Review

“…In order to solve the above problems, many studies have reported the method of interfacial coating. [ 159–165 ] A reasonable design of the interface coating can reduce the electronic conduction and interface resistance between the SSE and the electrode while providing a physical barrier to prevent the occurrence of side reactions, such as Li plating, at the interface. Han et al [ 138 ] used ALD method to deposit Al 2 O 3 on garnet‐type Li 7 La 2.75 Ca 0.25 Zr 1.75 Nb 0.25 O 12 (LLCZN), which significantly improved the wettability and stability of the interface between the SSE and lithium metal.…”