Coal-Based Semicoke-Derived Carbon Anode Materials with Tunable Microcrystalline Structure for Fast Lithium-Ion Storage

Abstract

Fast charging capability is highly desired for new generation lithium-ion batteries used in consumer-grade electronic devices and electric vehicles. However, currently used anodes suffer from sluggish ion kinetics due to limited interlayer distance. Herein, the coal-based semicoke was chosen as precursor to prepare cost-effective carbon anodes with high-rate performance through a facile pyrolytic strategy. The evolution of microstructure and its effect on electrochemical performance are entirely studied. The results show that large number of short-ordered defective structures are generated due to the occurrence of turbostatic-like structures when pyrolyzed at 900 °C, which are propitious to large interlayer distance and developed porous structure. High accessible surface area and large interlayer spacing with short-ordered defective domains endow the sample treated at 900 °C under argon (A900) with accelerated ion dynamics and enhanced ion adsorption dominated surface-induced capacitive processes. As a result, A900 delivers high capacity (331.1 mAh g−1 at 0.1 A g−1) and long life expectancy (94.8% after 1000 cycles at 1 A g−1) as well as good rate capability (153.2 mAh g−1 at 5 A g−1). This work opens a scalable avenue to fabricating cost-effective, high-rate, and long cycling life carbon anodes.

Nitrogen-Doped Porous Carbon Derived from Coal for High-Performance Dual-Carbon Lithium-Ion Capacitors

“…Compared to the other three groups of samples, the capacity retention rate of optimized CTK-1.0 was up to 97%, showing the best cyclic stability. This might have been due to the appropriate defects and stable degree of the heteroatom doping on the surface of the CNPCs during the activation process, which provided more active sites for Li + storage [ 51 ], leading to a better rate performance and cycle stability.…”

“…By linear fitting the log ( i )-log ( ) curve, the value of b can be calculated. When the b -value approaches 0.5, the electrochemical reaction is dominated by a diffusion-controlled intercalation process, whereas a b -value near 1.0 indicates a capacitive-controlled process [ 51 ]. As shown in Figure 4 b, the CTK-1.0 electrode had a b value approximately equal to 0.7 within scanning rate range of 0.1–2.0 mV s −1 , indicating the coexistence of capacitive behavior and diffusion control behavior.…”

“…As shown in Figure 4 b, the CTK-1.0 electrode had a b value approximately equal to 0.7 within scanning rate range of 0.1–2.0 mV s −1 , indicating the coexistence of capacitive behavior and diffusion control behavior. The synergistic effect of the capacitive behavior and diffusion behavior of the material was conducive to realizing rapid charge transfer and an enhanced long-term cycling stability [ 51 ]. In addition, the capacitive contribution of the Li + storage to the total capacity can be calculated based on the following equation [ 53 ]: where and are constants by linear fitting, with and corresponding to diffusion-controlled and pseudocapacitive-controlled processes, respectively.…”

Synthesis of Porous Carbon Nanomaterials from Vietnamese Coal: Fabrication and Energy Storage Investigations

“…The as-synthesized HOG was more hydrophilic and dispersed easily in aqueous solutions, and it was more oxidized than GO prepared using the Hummers method. Yaxiong Liu [18] successfully fabricated the positive electrode in a Li-ion battery from coke activated by HF and HCl and then calcined at 600 • C and 900 • C for 1 h. Seung Eun Lee et al [19] fabricated carbon materials from ordinary coke and calcined coke at 1300 • C. After one of these treatment methods, the material can be further processed to produce nanocarbon materials, such as graphene and carbon nanotubes using sonication, exfoliation, and hydrothermal synthesis.…”

Biomass Alginate Derived Oxygen-Enriched Carbonaceous Materials with Partially Graphitic Nanolayers for High Performance Anodes in Lithium-Ion Batteries

“…Biomass is an abundant carbon source that may be processed into carbon compounds by carbonization, pyrolysis, and activation techniques. A complex and efficient hierarchical structure with naturally interconnected scaffolds is common in carbon collected from natural resources [ 31 ]. The anode materials for lithium storage to date have included a variety of carbon compounds derived from biomass carbon precursors [ 32 , 33 , 34 , 35 ].…”