Cellulose-coated graphene composite carbon aerogel as well as preparation method and application thereof

Abstract

The invention discloses cellulose-coated graphene composite carbon aerogel as well as a preparation method and application thereof. The preparation method comprises the following steps: adding cotton cellulose into a sodium hydroxide solution; placing a mixed solution formed in the previous step at a low temperature, mixing the mixed solution with a graphene oxide solution at a low temperature, and then performing stirring to obtain a cellulose-coated graphene oxide mixed solution; pouring the cellulose-coated graphene oxide mixed solution into a mold, and conducting standing at room temperature to obtain cellulose-coated graphene oxide hydrogel; carrying out freeze drying on the cellulose-coated graphene oxide hydrogel to obtain cellulose-coated graphene oxide aerogel; and carrying out high-temperature pyrolysis on the cellulose-coated graphene oxide aerogel to obtain the cellulose-coated graphene composite carbon aerogel. The cellulose-coated graphene composite carbon aerogel is used in an electrode structure for inducing directional growth of lithium dendrites so as to achieve the effect of protecting a battery diaphragm.

Description

technical field [0001] The invention relates to the field of lithium metal batteries, and relates to a strategy for directional growth of lithium dendrites by inducing current distribution, in particular to a cellulose@graphene composite carbon aerogel and its preparation method and application. Background technique [0002] The rapid growth of the electric vehicle market has aroused extensive research interest in next-generation batteries to meet the growing demand for high power performance, high energy density, and long cycle life. Because of its high theoretical capacity (3860mAh g -1 ), lower electrochemical potential (-3.040V vs standard hydrogen electrode) and 0.534g cm -3 The low density is often selected as the negative electrode material. However, lithium metal electrodes have serious safety concerns. The culprit of these problems seems to come from the uncontrolled growth of lithium dendrites, which will lead to internal short circuit, thermal runaway, etc., wh...

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Problems solved by technology

However, these strategies still cannot change the upward growth direction of the dendrites at the separator / electrolyte interface, and the battery separator still poses a safety hazard as the cycle progresses.

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