Balsa wood-derived binder-free self-standing carbon foam negative electrode material and preparation method thereof

Abstract

The invention provides a balsa wood-derived binder-free self-standing carbon foam negative electrode material and a preparation method thereof. The self-standing carbon foam negative electrode material is prepared by taking balsa wood as a precursor through a carbonization method; the self-standing carbon foam negative electrode material has a unique multi-layer and three-dimensional cross-linkedstructure of balsa wood; the three-dimensional cross-linked structure is composed of tubular structures which are evenly distributed and nanopores distributed in the inner wall of the pipeline, so thethree-dimensional cross-linked structure with the interiors connected with one another is formed; and the three-dimensional cross-linked structure of the self-supporting carbon foam negative electrode material can accelerate permeation of an electrolyte, provide a rapid transmission channel for electrons and ions and improve reaction kinetics. The method comprises the following steps: cleaning and drying the balsa wood precursor; carrying out pre-oxidation treatment on the balsa wood at the temperature of 210-230 DEG C; and then annealing and carbonizing for 1-3h at 700-1200 DEG C to obtain the binder-free self-standing carbon foam negative electrode material. The potassium ion battery negative electrode material which is safe and stable in electrochemical performance and does not need touse a binder can be obtained.

Description

【Technical field】 [0001] The invention relates to a potassium ion battery and a negative electrode material of the potassium ion battery, in particular to a binder-free self-supporting carbon foam negative electrode material derived from balsa wood and a preparation method thereof. 【Background technique】 [0002] With the increasing demand for new-generation storage systems, high-energy-density alkali metal anode secondary batteries have attracted much attention. Potassium-ion batteries (KIBs) are expected to be an alternative to Li-ion batteries due to their abundant reserves, similar redox potential and the same rocking-chair energy storage mechanism as Li-ion batteries (LIBs). Thanks to K + The size of the ion is larger (K + for Li + for ), so the structure of the electrode material will be at K + Deformation and crushing during ion intercalation / deintercalation, which severely limit the cycle performance of K-ion batteries and their anode development. Therefore,...

AI Technical Summary

Problems solved by technology

Furthermore, the contact area between the active material and the electrolyte in the traditional electrode is small, which is not conducive to the infiltration of the electrolyte.

During cycling, large volume expansion can also lead to electrode crushing and detachment

Therefore, it remains a challenge for KIBs to develop suitable three-dimensional self-supporting free-standing electrodes with stable structures, high electrochemical performance, and no binders.

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