3D printed solid-state battery and preparation method and application thereof

Abstract

The invention provides a 3D printed solid-state battery and a preparation method and application thereof. The 3D printed solid-state battery comprises a positive pole piece, a negative pole piece and a solid-state electrolyte located between the positive pole piece and the negative pole piece, wherein the positive pole piece comprises the following raw materials in percentage, by mass, 70-80% of a positive active material, 5-10% of an electronic conductive agent, 2-10% of an ionic conductive agent, 2-4% of LiTFSI, 1.5-5% of polyvinylidene fluoride, 4-6% of polyoxyethylene and a positive solvent; and the solid content of raw materials of the positive pole piece accounts for 20-50% of the solid content of the positive solvent. The 3D printing technology is adopted, the solid electrolyte with precise surface appearance and internal structure is designed, interface contact between the electrolyte and an electrode is improved, ion transfer between the electrode and the electrolyte is improved, and in addition, lithium ion transmission between the positive electrode and the solid electrolyte is improved by combining with a polymer composite positive electrode added with polyoxyethylene.

Description

technical field [0001] The invention relates to the field of lithium-ion batteries, and relates to a 3D printed solid-state battery and a preparation method and application thereof. Background technique [0002] In recent years, due to the increasing demand for energy, electrochemical energy storage has become the most widely used energy storage technology. Among them, lithium-ion batteries have become one of the focuses of research because of their high energy density and long cycle life. With the continuous optimization of lithium-ion battery technology, there is an increasing demand for the energy density of lithium-ion batteries. Due to the high specific capacity and low electrochemical potential, the energy density can be increased by about 50% theoretically by using lithium metal instead of graphite anode. At present, traditional lithium-ion batteries still use organic liquid electrolytes. Although they have high ionic conductivity and good electrode wettability, the...

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Problems solved by technology

However, after the invention is sintered, the interface modification layer will have the disadvantage of not being closely bonded to the metal negative electrode interface, so the interface resistance will be increased.

[0005] CN110518278A discloses a solid electrolyte with a negative electrode interface layer, a preparation method and a solid battery. The surface of the solid electrolyte has a liquid metal alloy layer, and the liquid metal alloy layer modifies the negative electrode interface where the solid electrolyte contacts the lithium metal negative electrode. After the solid-state electrolyte is assembled into a solid-state battery, the transition effect of the liquid metal alloy layer can improve the solid-solid compatibility problem between the lithium metal negative electrode and the solid-state electrolyte material interface, and reduce the interface resistance, but the amount of electrolyte added Insufficient electrolyte will cause the battery to dive late in the cycle, while too much electrolyte will reduce the safety performance of the battery

However, under external pressure, material rupture and electrical performance degradation may occur, which is not conducive to the long-term cycle of the battery

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