Large-scale synthesis of highly structural-connecting carbon nanospheres as an anodes material for lithium-ion batteries with high-rate capacity

Ultrafine SnO2 Nanoparticles Decorated on N-Doped Highly Structurally Connected Carbon Nanospheres as Anode Materials for High-Performance Sodium-Ion Batteries

“…For comparison, the electrochemical performances of related studies are listed in Table 3. Moreover, the Na + diffusion coefficient (D Na + ) was calculated from the EIS data's low-frequency region using the following equationseqs 3 and 4 35…”

“…For comparison, the electrochemical performances of related studies are listed in Table . Moreover, the Na + diffusion coefficient ( D Na + ) was calculated from the EIS data’s low-frequency region using the following equationseqs and where D Na + denotes the Na + diffusion coefficient, R denotes the gas constant (8.314 J mol –1 k –1 ), T denotes the test temperature (298 K), n denotes the number of the transferred electrons, F denotes the Faraday constant (96,500 C mol –1 ), A denotes the area of the cathode/anode interface (1.442 cm 2 ), C denotes the concentration of Na + , and the Warburg factor, which corresponds to the parameter- Z re (ω = 2 f ), is denoted by σ. As shown in Figure d, the calculated Na + diffusion coefficients ( D Na + ) for N-HS-CCN, SnO 2 /N-HS-CCN, SnO 2 /HS-CCN, and SnO 2 are 1.86 × 10 –15 , 8.39 × 10 –15 , 6.89 × 10 –15 , and 6.32 × 10 –16 , respectively.…”

“…A detailed procedure for the synthesis is described in our previous article. 35 To eliminate contaminants, the prepared HS-CCN was treated with 2 M nitric acid at 120 °C for 10 h and then flushed with deionized water until the flushed water reached a pH of 7. For the N-doped HS-CCN, 0.42 g of urea was dispersed in 50 mL of deionized water, and 0.84 g of HS-CCN was ultrasonically dispersed in the resultant solution for 30 min and then dried at 60 °C for 10 h. The obtained sample followed an annealing step in a furnace at the temperature of 500 °C for 3 h under Ar (flow rate was 40 mL min −1 , heating rate was 5 °C min −1 ) to obtain the N-doped carbon material(N-HS-CCN).…”

“…The as-prepared HS-CCN yielded about 1 kg h –1 . A detailed procedure for the synthesis is described in our previous article . To eliminate contaminants, the prepared HS-CCN was treated with 2 M nitric acid at 120 °C for 10 h and then flushed with deionized water until the flushed water reached a pH of 7.…”

Hydrogen-Type Binding Sites in Carbonaceous Electrodes for Rapid Lithium Insertion

“…At charging rates above 1 C (i.e., a 60 min charging time), the reversible capacity of crystalline graphite is precipitously reduced owing to sluggish desolvation kinetics of lithium from within standard liquid carbonate electrolytes at the surface of the graphite anode. − Recent work has shown that the rate capability is correlated with specific properties of the chosen type of graphite, including such properties as crystallite size, particle size, and content and type of lattice imperfections; reasonable capacity can be retained in high-performance variants up to roughly 4 C (i.e., a 15 min charging time) but requires a precisely tuned, anode-limited full-cell . Other methods have been shown to elevate the rate capability of graphite through modification strategies such as laser patterning and nanosizing, increasing the complexity of electrode fabrication. − On the other hand, high-surface-area porous carbon materials can effectively store lithium under ultrafast charging rates via the capacitive adsorption of ions and formation of an electric double-layer at their surfaces . The reversible capacity of these materials increases with surface area to far higher than 372 mA h g –1 ; − however, due to decomposition of the electrolyte and the resulting formation of solid electrolyte interphase (SEI) on all exposed surfaces of the electrode, a massive irreversible consumption of electrolyte occurs during the first cycle in standard Li-ion electrolytes, prohibitive to their use in commercial battery applications …”