Carbon coating on the cathode surface has emerged as a promising technique to enhance lithium-ion battery performance. Lithium-ion batteries (LIBs) have revolutionized portable electronics and electric vehicles due to their high energy density and excellent cycling stability. However, to meet ever-increasing energy demands, improving the electrochemical performance of LIBs remains a key research focus.
Benefits of Carbon Coating on LIB Cathodes:
a. Improved Electrochemical Performance: Carbon coating modifies the surface chemistry of the cathode material, leading to improved specific capacity and cycle stability. It enhances structural stability and increases Li-ion diffusion, resulting in better overall battery performance.
b. Nanoscale Coating for Larger Cathode Particles: Deposition techniques allow nanoscale carbon particles to coat larger cathode particles effectively, leading to enhanced electrochemical properties in LIBs.
c. Prospective Drying Methods: Drying methods have shown promise in improving the uniformity and coverage of the carbon coating layer on cathode materials.
d. Carbon Sources and Emerging Materials: Carbon from sucrose and other emerging carbon-based materials, such as graphene and carbon nanotubes (CNTs), have demonstrated remarkable potential in improving specific capacity and performance in LIBs.
Limitations of Carbon Coating on LIB Cathodes:
a. Lack of Comprehensive Studies: While research has focused on the impact of carbon coating materials and methods on cathode performance, more comprehensive studies on factors like coating layer thickness, homogeneity, and electron diffusion behavior are needed.
b. Uniformity and Integrity: Ensuring the uniformity and integrity of the carbon coating layer is crucial, as any structural destruction during cycling may hinder battery performance.
c. Surface Characteristics of Cathode Materials: Understanding and optimizing the compatibility between the surface of the cathode material and the carbon coating material are essential to effectively modifying the cathode.
d. Carbon Content in Coating: Determining the ideal carbon content in the coating is challenging, as both excessive and insufficient carbon can negatively affect specific capacity and Li-ion diffusion coefficient.
Future Outlook:
a. Developing Convenient Coating Methods: New coating technologies that offer simplicity, yet superior uniformity, need to be explored.
b. Carbon Composite Coating: Investigate the use of carbon composite materials for cathode modification to enhance the power and energy density of LIBs.