A solid battery capacitor

Abstract

The invention discloses a solid-state battery capacitor which comprises a positive electrode, a negative electrode and a solid electrolyte and is characterized in that the solid electrolyte is a lithium salt, polyvinylidene fluoride and polyvinyl acetate composite film, both the positive and negative electrode active materials are graphite material, and the negative graphite material is pre-lithiated. According to the solid-state battery capacitor of the present invention, a good solid solution can be formed with the positive electrode and the negative electrode during a charge-discharge cycle, a stable interfacial effect can be generated, the first-time charge-discharge efficiency and the Coulomb efficiency in the circulation process are greatly improved, the impedance is reduced, the pre-lithitic graphite electrode is adopted by the negative electrode, the loss of lithium salt during a charge and discharge process can be significantly reduced, the cycle life is greatly increased, andthe leakage current is reduced at the same time. The working voltage of the solid-state battery capacitor can reach 5.35V, and the energy density is greatly increased. In addition, the solid electrolyte is used, and the safety performance is ensured.

Description

technical field [0001] The invention belongs to the field of power / energy storage batteries, in particular to a solid-state battery capacitor. Background technique [0002] The increasing energy crisis and environmental problems have accelerated the rapid development of the new energy industry. Under the current situation, the environment-friendly electrochemical energy storage technology that maximizes green energy supply and low-carbon energy conservation and emission reduction has attracted more and more attention. Recently, the state has proposed to establish a near-zero carbon emission project based on the Energy Internet, the core content of which includes renewable energy power generation, distributed energy storage technology, etc., which puts forward higher requirements for new and efficient energy storage technologies. In addition, new energy Electrochemical energy storage devices with high energy density and high power density are also required in fields such as ...

AI Technical Summary

Problems solved by technology

[0004] In principle, the conventional battery capacitor adopts the negative electrode through electrochemical intercalation of Li + , the positive electrode uses physical adsorption PF 6 - The electrolyte is a liquid organic system, the working voltage is 3.8V, the energy density is 10~20Wh / kg, and the power density is 3000~5000W / kg. Another battery capacitor relies on the negative electrode to physically adsorb Li + Cations and cathodes are electrochemically intercalated into PF 6 - For energy storage, the electrolytes of the above two battery capacitors all use liquid organic electrolytes, the embedded active materials are graphite materials, and the adsorption material is porous carbon. The disadvantage of using organic electrolytes is that their safety performance is poor, and it is easy to use them under abuse conditions. Fire and explosion; one pole uses physical adsorption charge to store energy, which makes the leakage current large; in addition, for the latter battery capacitor, in the liquid electrolyte system, PF 6 - During the repeated embedding / extraction process, the surface of the active material will continue to peel off, the interface will be destroyed, and irreversible reactions will occur repeatedly, so that the irreversible capacity will continue to be generated, and the first charge and discharge efficiency and the Coulombic efficiency during the long-term cycle process will be low.