The present invention relates to a preparation method of a carbon quantum dot/carbon coated VSe.sub.2 composite material (VSe.sub.2@CQD), and belongs to the technical field of electrode material of a potassium ion battery and preparation thereof. By compositing the carbon, carbon quantum dots and vanadium diselenide (VSe.sub.2), the three components generate a synergistic effect. The carbon quantum dot/carbon coating can improve the electronic conductivity and lithium ion diffusion rate of the material, and also can inhibit the agglomeration of the vanadium diselenide (VSe.sub.2). Therefore, the prepared carbon quantum dot/carbon coated VSe.sub.2 composite material (VSe.sub.2@CQD) has excellent electrochemical performance and excellent rate performance and cycle stability. The method is simple in process, low in cost, environment-friendly, and suitable for large-scale industrial production.

A rechargeable transition metal battery includes a negative electrode, a positive electrode and an electrolyte. The negative electrode includes a negative electrode material which is a transition metal or an alloy of the transition metal. The positive electrode is electrically connected to the negative electrode and includes a host material and a positive electrode material. The host material includes a carbon. The positive electrode material is connected to the host material, and the positive electrode material is a compound of a metal, an elemental chalcogen or an elemental halogen. The electrolyte is disposed between the positive electrode and the negative electrode.

The disclosure provides a preparation method of a vanadium selenide/carbon cellulose composite, belonging to the technical fields of electrode materials of potassium ion batteries and preparation technologies thereof. Through compounding of carbon, carbon cellulose and vanadium diselenide (VSe.sub.2), a synergistic effect occurs between two components, and carbon cellulose-carbon coating is capable of increasing electron conductivity and potassium ion diffusion rate of a material while inhibiting the agglomeration of vanadium diselenide (VSe.sub.2). Therefore, the prepared vanadium selenide/carbon cellulose composite has excellent electrochemical performance and exhibits outstanding rate performance and cycling stability. The method is simple in process, low in cost, environmentally friendly, and suitable for large-scale industrial production.

An electrolyte for a lithium-sulfur battery including a lithium salt, a non-aqueous organic solvent, and an additive. The non-aqueous organic solvent includes an ether compound and a heterocyclic compound. The heterocyclic compound includes one or more double bonds and comprises an oxygen atom or a sulfur atom. The additive includes a carbonate compound.

Provided herein are core-shell heterostructures design comprising a metal (e.g., noble metal) nanoparticle core and a transition metal dichalcogenide (TMD) shell, and methods of preparation and use thereof. In particular embodiments, the core-shell heterostructures described herein are synthesized by direct growth of a monolayer or multilayer fullerene-like TMD shell on a metal (e.g., noble metal) nanoparticle core, exhibit unique Raman scattering and photoluminescence characteristics, and are useful, for example, in plasmonic hot electron enhanced optics and optoelectronics.

Methods of synthesizing few-layer two-dimensional (2D) Sb.sub.2S.sub.3 nanosheets using scalable chemical exfoliation are provided. The 2D Sb.sub.2S.sub.3 nanosheets can be developed as bi-functional anode materials in both lithium ion batteries and sodium ion batteries. The unique structural and functional features brought by 2D Sb.sub.2S.sub.3 nanosheets can offer short electron/ion diffusion paths and abundant active sites for surface redox reactions.

A solid-state ion conductor including a compound of Formula 1:

Li.sub.1+(4-a)yA.sup.a.sub.yM.sub.1-yXO.sub.5   Formula 1

wherein, in Formula 1, A is an element of Groups 1 to 3 or 11 to 13, or a combination thereof, wherein an oxidation state a of A is 1≤a≤3, M is an element having an oxidation state of +4 of Groups 4 or 14, or a combination thereof, X is an element having an oxidation state of +5 of Groups 5, 15, 17, or a combination thereof, and 0<y≤1.

Methods of making a sintered electrode comprise forming a slurry including 40 wt % to 75 wt % of a powder comprising a chalcogenide and at least one of an alkali metal or an alkaline earth metal, 1 wt % to 10 wt % of a binder, and 30 wt % to 50 wt % of a solvent. Methods include casting the slurry into a green tape. Methods include drying the green tape to form a dried green tape by removing at least a portion of the solvent. The dried green tape includes at most 10 wt % of organic material in the dried green tape. Methods include sintering the dried green tape at a temperature from 500° C. to 1350° C. for no more than 60 minutes to form the sintered electrode.

The present invention relates to the application of a force to enhance the performance of an electrochemical cell. The force may comprise, in some instances, an anisotropic force with a component normal to an active surface of the anode of the electrochemical cell. In the embodiments described herein, electrochemical cells (e.g., rechargeable batteries) may undergo a charge/discharge cycle involving deposition of metal (e.g., lithium metal) on a surface of the anode upon charging and reaction of the metal on the anode surface, wherein the metal diffuses from the anode surface, upon discharging. The uniformity with which the metal is deposited on the anode may affect cell performance. For example, when lithium metal is redeposited on an anode, it may, in some cases, deposit unevenly forming a rough surface. The roughened surface may increase the amount of lithium metal available for undesired chemical reactions which may result in decreased cycling lifetime and/or poor cell performance. The application of force to the electrochemical cell has been found, in accordance with the invention, to reduce such behavior and to improve the cycling lifetime and/or performance of the cell.

The present invention relates to the application of a force to enhance the performance of an electrochemical cell. The force may comprise, in some instances, an anisotropic force with a component normal to an active surface of the anode of the electrochemical cell. In the embodiments described herein, electrochemical cells (e.g., rechargeable batteries) may undergo a charge/discharge cycle involving deposition of metal (e.g., lithium metal) on a surface of the anode upon charging and reaction of the metal on the anode surface, wherein the metal diffuses from the anode surface, upon discharging. The uniformity with which the metal is deposited on the anode may affect cell performance. For example, when lithium metal is redeposited on an anode, it may, in some cases, deposit unevenly forming a rough surface. The roughened surface may increase the amount of lithium metal available for undesired chemical reactions which may result in decreased cycling lifetime and/or poor cell performance. The application of force to the electrochemical cell has been found, in accordance with the invention, to reduce such behavior and to improve the cycling lifetime and/or performance of the cell.