Polyanions Enhance Conversion Reactions for Lithium/Sodium‐Ion Batteries: The Case of SbVO₄ Nanoparticles on Reduced Graphene Oxide

Abstract

Anode materials based on redox alloying/dealloying reactions are regarded as one of the promising electrodes in Li/Na‐ion batteries. However, the enormous volume change upon cycling induces the giant structure strain, particle pulverization and then capacity decay. Here, vanadates are proposed to mitigate this concern for alloy‐type anode materials, using SbVO4 as an example. As indicated by density function theory and in situ/ex situ techniques, VO43− enhances the conversion reaction between Sb3+ and Sb, buffers the structure change induced by alloying/dealloying reactions of Sb and exhibits the electrochemical activity to Li ions. These results make SbVO4 superior to Sb, Sb2O3 and SbPO4 in the electrochemical performances, which applies both to lithium‐ion batteries and to sodium‐ion batteries. Then, the structure design and carbon composite are achieved by depositing monodispersed SbVO4 nanocrystals on reduced graphene oxides via a simple solvothermal reaction. This composite shows a good cycling stability and a high rate capability, especially in sodium‐ion batteries (73.6% after 1500 cycles at 1 A g−1, or 252 mAh g−1 at 10 A g−1). These results open the door for other alloy‐type anode materials to improve the performances.

Principles and Applications of Galvanostatic Intermittent Titration Technique for Lithium-ion Batteries

“…Internal resistance (19) Internal resistance analysis has been widely applied to obtain more insights into the reaction kinetics in various SOCs of the lithiation/delithiation processes or in comparing systems [34,[54][55][56][57][58]. For example, Chae et al [57] conducted a comparative analysis of two nano-sized zinc oxide (ZnO) electrodes in which conductive carbon is embedded in different ways (Fig.…”

Self-Formed Channel Boosts Ultrafast Lithium Ion Storage in Fe3O4@Nitrogen-Doped Carbon Nanocapsule

“…Figure 3f and Figure S11 in the Supporting Information show the potential−capacity curves under multiple pulses of Fe 3 O 4 @NC and pure Fe 2 O 3 , respectively, which both experienced 80 cycles. We can directly observe that it has a smaller polarization potential (ΔU) for Fe 3 O 4 @NC, 37,38 Δ = − U QOCV CCV compared to that of pure Fe 2 O 3 , as shown in insets of Figure 3f and Figure S11. Here, QOCV is the quasi-open-circuit voltage and CCV is the closed circuit voltage.…”

Cubic MnV2O4 fabricated through a facile sol–gel process as an anode material for lithium-ion batteries: morphology and performance evolution

“…18 Yang et al produced an SbVO 4 /rGO nanocomposite anode for LIBs and achieved a specific capacity of 782 mA h g −1 after 100 cycles at 100 mA g −1 . 19 Even if the above materials represent satisfactory electrochemical properties as anode materials for LIBs, the valence state of vanadium in the synthesis process is complex. Considering the economic and environmental aspects, there is a lack of suitable synthesis routes to satisfy the demands of being environment-friendly, low-cost, facile processes that are suitable for large-scale synthesis of high-purity anode materials with admirable electrochemical performance.…”