A sodium storage hard carbon anode based on an intercalation-electroplating hybrid mechanism and its preparation method

Abstract

The invention belongs to the technical field of sodium ion electrode materials, and in particular relates to a sodium storage hard carbon negative electrode based on an intercalation-electroplating hybrid mechanism and a preparation method thereof. The design of this application adopts ionic liquid (low temperature molten salt) electroplating method to directly plate Ag, Cu and other sodium-friendly metal nanoparticles on the hard carbon film electrode to achieve uniform deposition of sodium metal negative electrode, and finally obtain high-capacity and high-stability intercalation ‑Electroplated hard carbon based sodium storage negative electrode. The biggest feature of the ionic liquid used in this application is the absence of H + , can prevent the electrode template from falling off when it comes into contact with water, and its electrochemical window is as high as 2.23 V. The application temperature is low, energy-saving and non-toxic and green, and more importantly, it can effectively adjust the size of metal particles, and it can be used as a sodium metal negative electrode material. out of excellent performance.

Description

Technical field [0001] The present invention belongs to the technical field of sodium ion electrode materials, specifically relates to a sodium storage hard carbon negative electrode based on embedding - electroplating mixing mechanism and preparation method thereof. Background [0002] In the era of information technology, rechargeable batteries have become an important part of electronic devices. Sodium is highly abundant and theoretically specific to capacity (1166 mA h g -1 ) and other advantages are expected to become a very attractive negative electrode for post-lithium battery design. However, similar to lithium metal electrodes, the sodium metal negative electrode also has problems such as uncontrollable growth of dendrites, unstable SEI membrane and large volume changes, resulting in rapid cyclic attenuation of the sodium metal negative electrode. Hard carbon is a typical embedded sodium storage carbon anode, the volume change during the sodium storage process is small, ...

AI Technical Summary

Problems solved by technology

However, similar to lithium metal electrodes, sodium metal anodes also have problems such as uncontrollable dendrite growth, unstable SEI film and large volume change, which lead to rapid cycle decay of sodium metal anodes.

Hard carbon is a typical embedded sodium storage carbon anode, the volume change is small during the sodium storage process, and the cycle performance is stable, but the capacity based on the embedded sodium storage mechanism is not high (reversible capacity is less than 300 mA hg -1 )

Images