Three-dimensional framework material mixed liquor, three-dimensional composite solid electrolyte membrane, preparation method of positive plate and solid lithium battery

Abstract

The invention relates to the technical field of solid lithium batteries, and particularly discloses a three-dimensional skeleton mixed solution, a three-dimensional composite solid electrolyte membrane, a preparation method of a positive plate and a solid lithium battery. A preparation method of a three-dimensional framework material mixed solution comprises the following steps: step 1, dispersing an inorganic solid electrolyte in an organic solvent according to a certain amount, stirring the raw materials with the mass fraction of 40-60% at normal temperature to obtain a mixed solution, adding a surfactant into the mixed solution, stirring at normal temperature, and carrying out electrostatic spinning treatment to obtain a precursor; 2, calcining the electrostatic spinning precursor to obtain a three-dimensional framework material; putting the three-dimensional framework material into water, stirring to obtain a turbid liquid, continuously adding the emulsion adhesive, uniformly stirring and mixing at normal temperature, adding the lithium salt, and fully stirring and mixing at normal temperature to obtain a three-dimensional framework material mixed liquid; and then the prepared three-dimensional composite solid electrolyte membrane and positive plate are pressed into the solid lithium battery, and the solid lithium battery has the effects of high conductivity and long cycle life.

Description

technical field [0001] The invention relates to the technical field of solid lithium batteries, in particular to a preparation method of a three-dimensional skeleton material mixed solution, a three-dimensional composite solid electrolyte membrane, a positive electrode sheet, and a solid lithium battery. Background technique [0002] The wide application of lithium batteries in 3C electronics, electric vehicles, and distributed energy storage highlights the necessity of improving safety and energy density; due to their high specific capacity, lithium anode sheets can significantly improve the energy density of solid lithium batteries, but Cycling in a liquid electrolyte, moss-like or dendritic lithium dendrites will be generated at the lithium metal interface, resulting in a short circuit of the battery, so a solid electrolyte is used to replace the liquid electrolyte; solid electrolytes are mainly divided into ceramic inorganic solid electrolytes and polymer solid electrolyt...

AI Technical Summary

Problems solved by technology

[0002] The wide application of lithium batteries in 3C electronic products, electric vehicles and distributed energy storage highlights the necessity of improving safety and energy density; due to its high specific capacity, lithium negative electrodes can significantly improve the energy density of solid lithium batteries, but Circulating in the liquid electrolyte, mossy or dendritic lithium dendrites will be generated on the lithium metal interface, resulting in a short circuit of the battery, so solid electrolytes are used instead of liquid electrolytes; solid electrolytes are mainly divided into ceramic inorganic solid electrolytes and polymer solid electrolytes. Electrolyte batteries mainly face two problems: the first is that the ceramic inorganic solid electrolyte is too hard to be tightly combined with metal lithium, and the interface resistance is too large. The polymer solid electrolyte has good interface contact and mechanical compatibility with the electrode, but lithium The ionic conductivity is low, adding rigid inorganic solid electrolytes as active fillers to flexible polymer solid electrolytes, and constructing composite solid electrolytes is one of the most effective ways to improve the performance of solid electrolytes; the second is the poor lithium ion transport performance of the positive electrode sheet , most solid lithium batteries are designed with thin pole pieces, which leads to a decrease in the actual energy density of the battery, so it is necessary to optimize the conductivity of the pole piece to increase the thickness of the pole piece

[0004] However, the low lithium ion conductivity of polymer solid electrolytes and positive electrodes limits the development and use of high-energy-density all-solid batteries. and high-capacity all-solid lithium batteries play a key role. The existing technical solutions are not comprehensive enough and have certain technical limitations.