Ferrous carbonate/graphene composite material for negative electrode of sodium-ion battery as well as preparation method and application thereof

Abstract

The invention provides a ferrous carbonate / graphene composite material for a negative electrode of a sodium-ion battery as well as a preparation method and an application thereof. According to the invention, the ferrous carbonate / graphene composite material is prepared by adopting a hydrothermal method and taking graphene oxide, divalent iron salts, a reducing agent and water-soluble carbonate or urea as raw materials. The composite material is uniform in size, can be applied to sodium ion negative electrodes, has relatively good electrochemical performance, and has excellent rate performance and cycling stability. In addition, the preparation method provided by the invention is strong in operability and good in reproducibility, and prepared products are stable in quality.

Description

technical field [0001] The invention relates to a ferrous carbonate / graphene composite material for a negative electrode of a sodium ion battery, a preparation method and application thereof, and belongs to the technical field of electrochemistry. Background technique [0002] Compared with lithium-ion batteries, sodium-ion batteries have the advantages of abundant sodium resources and low raw material prices, and have great application prospects in the field of large-scale energy storage. The anode material of sodium ion battery, as one of the important components of the battery, has an important impact on its performance. At present, the sodium storage anode materials with intercalation mechanism have received more attention due to their high cycle stability, mainly including hard carbon, Na 2 Ti 3 o 7 and Li 4 Ti 5 o 12 wait. Among these sodium storage anode materials, Na 2 Ti 3 o 7 and Li 4 Ti 5 o 12 The specific capacity is usually less than 200mAh g -1 , ...

AI Technical Summary

Problems solved by technology

Disclosed as Chinese patent document CN105609745A is a nickel selenide / graphene sodium ion battery composite negative electrode material and its preparation method and application; Disperse the nickel source of graphene, mix it with the selenium source for hydrothermal reaction, filter, wash, and vacuum dry; this method is low in cost, suitable for the practical application of sodium ion batteries, and can achieve industrial scale production, but the composite material The specific capacity is not good when applied to the negative electrode of sodium ion battery

Another example is that the Chinese patent document CN105336940A discloses a sodium titanate nanowire / graphene composite negative electrode material and a preparation method thereof; the preparation method includes the following steps: dissolving graphite oxide in an organic solvent, adding a titanium source, mixing and processing, and performing The first solvothermal reaction is to obtain titanium dioxide / graphene composite; NaOH aqueous solution is added to carry out the second solvothermal reaction to obtain sodium titanate nanowire / graphene crude product; after washing and drying, sodium titanate nanowire Wire / graphene composite negative electrode material; the preparation method of the invention is cumbersome, and the prepared composite material has poor specific capacity under high current density when applied to the negative electrode of sodium ion battery

However, there is no report about ferrous carbonate as a negative electrode material for sodium-ion batteries.

However, as an anode material for sodium-ion batteries, ferrous carbonate may have the disadvantages of large volume changes during cycling, resulting in structural instability and low conductivity.

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