Novel Surface Coating Strategies for Better Battery Materials

Abstract

With the advancement of electrode materials for lithium-ion batteries (LIBs), it has been recognized that their surface/interface structures are essential to their electrochemical performance. Therefore, the engineering of their surface by various coating technologies is the most straightforward and effective strategy to obtain the desirable battery characteristics. Coating the electrode materials' surface to form a specifically designed structure/composition can effectively improve the stability of the electrode/electrolyte interface, suppress structural transformation, improve the conductivity of the active materials and consequently lead to enhanced cycle stability and rate capability of LIBs. However, due to the restrictions of conventional coating methods, it is still very hard to obtain a conformal and multifunctional coating layer. This paper focuses on recent advances and summarizes the challenges in the development of surface coating technologies for LIBs. Based on these factors, the new concepts of 'ultrathin conformal coating', 'continuous phase coating' and 'multifunctional coating' are proposed and discussed, followed by the authors' rational perspectives on the future development and potential research hot spot in the surface/ interface engineering of LIB materials and systems.

Unveiling the physiochemical aspects of the matrix in improving sulfur-loading for room-temperature sodium–sulfur batteries

“…The poor ionic and electronic conductivity of the elemental sulfur cathode can be greatly improved through chemical modification of the sulfur matrix. The approach that has been investigated for improving the electronic conductivity is based on the coating technique, 44,45 which mainly involves coating a thin polymeric material to promote the inter-particle contact and chemical trapping of the dissolved intermediate sodium polysulfides. 46,47 Attempts have been made to design and develop various matrices with diverse chemical structures and morphologies, 48 which have significantly improved the stability of the sulfur cathode during the charge/discharge reactions.…”

Coating of Low-Cost Asphaltenes-Derived Carbon Fibers with V2O5 for Supercapacitor Application

“…Coating procedures, which are more straightforward and can be applied to industrial applications, are spray-coating, spin-coating, and dipping techniques, which are combined with heat treatments typically performed in air. 25 This work combines the advantage of using low-cost CFs derived from asphaltenes with a straightforward and facile dipping procedure to coat fibers with V 2 O 5 for supercapacitor applications. V 2 O 3 powder dissolved in dilute HNO 3 was used as an abundant and inexpensive precursor, with a lower environmental impact than that of organic precursors used for ALD.…”

Nonlithium Metal–Sulfur Batteries: Steps Toward a Leap

“…At this stage, the most successfully commercialized secondary batteries are the LIBs, which have been widely applied in a variety of devices, including mobile phones, power tools, and electric vehicles. In an LIB, electricity is stored and released based on the reversible insertion–extraction of Li ions in the electrode materials . The second‐generation LIBs, which are based on layered LiNi x Mn y Co z O 2 (NMC) or LiNi 0.8 Co 0.15 Al 0.05 O 2 (NCA) cathode materials and graphite anode materials, normally have practical gravimetric/volumetric energy densities as high as 180–220 Wh kg −1 and have been applied in the latest electric vehicles (e.g., the Tesla Model S car) ( Figure ).…”