Dip-Coating of Carbon Fibers for the Development of Lithium Iron Phosphate Electrodes for Structural Lithium-Ion Batteries

Abstract

This study describes a dip-coating method for applying an active material to commercially available intermediate modulus carbon fibers (CFs). A suite of tools were developed to assist with the handling and coating of CF tows to create disc electrodes. CF electrodes were fitted into 2025-type coin cells, for electrochemical analysis, first to determine their performance as anodes. Specimens of CFs were dip-coated with a slurry consisting of lithium iron phosphate, carbon black, and polyvinylidene fluoride, then dried, and fitted into half-cells to analyze the cathode performance. A cyclic voltammetry sweep was performed on each half-cell to determine suitable cycling potential limits, followed by galvanostatic cycling for a minimum of 30 cycles. Measured capacities for anode and cathode half-cells yielded 92 and 52.3 A h kg −1 , respectively. A full-cell with CFs in both electrodes was assembled and tested, revealing a capacity of 24.7 A h kg −1 after 30 cycles. Finally, both the anode and cathode were examined with a scanning electron microscope to establish a benchmark (anode) to compare surface topologies and to analyze the quality of the active material applied via dip-coating (cathode).

Preparation of Ceramic Fiber Threads with Enhanced Abrasion Resistance Performance

“…For post-treatment modification, the preparation process of the abrasion-resistant coatings and the selection of the abrasion-resistant modifiers are crucial. Common preparation processes for coatings include the sol-gel method [26], plasma-enhanced chemical vapor deposition method [27], spray-coating method [28], and dip-coating method [29]. Given the simplicity and cost-effectiveness of the preparation process and the wide range of available dipping modifiers, the dip-coating method is expected to be an effective and suitable preparation process to enhance the surface abrasion resistance performance of ceramic fiber threads.…”

Freestanding and Consecutive Intermixed N-Doped Hard Carbon@Soft Carbon Fiber Architectures as Ultrastable Anodes for High-Performance Li-Ion Batteries

“…Moreover, it can not only improve the efficiency of enterprises but also reduce environmental pollution and improve the utilization of secondary resources, which has important research significance. As LIB anode materials, the CTP-based soft carbon electrode has the advantages of a high carbon yield, good conductivity, good cycle stability, and relatively low price, but its specific capacity is lower than that of hard carbon material …”

“…As LIB anode materials, the CTP-based soft carbon electrode has the advantages of a high carbon yield, good conductivity, good cycle stability, and relatively low price, but its specific capacity is lower than that of hard carbon material. 5 In recent years, high-temperature pyrolyzed hard carbon has attracted considerable attention because of its higher theoretical specific capacity than that of graphite carbon, certain atomic doping, and large defects. 6 The carbon sources of hard carbon are mainly synthetic polymers and biomass materials.…”