An anode for a fluoride ion electrochemical cell is provided and includes a layered material of hard carbon, nitrogen doped graphite, boron doped graphite, TiS.sub.2, MoS.sub.2, TiSe.sub.2, MoSe.sub.2, VS.sub.2, VSe.sub.2, electrides of alkali earth metal nitrides, electrides of metal carbides, or combinations thereof. The anode may be included in a fluoride ion electrochemical cell, which additionally includes a cathode and a fluoride ion electrolyte arranged between the cathode and the anode. At least one of the cathode and the anode reversibly exchange the fluoride ions with the electrolyte during charging or discharging of the electrochemical cell.

An anode for a fluoride ion electrochemical cell is provided and includes a layered material of hard carbon, nitrogen doped graphite, boron doped graphite, TiS.sub.2, MoS.sub.2, TiSe.sub.2, MoSe.sub.2, VS.sub.2, VSe.sub.2, electrides of alkali earth metal nitrides, electrides of metal carbides, or combinations thereof. The anode may be included in a fluoride ion electrochemical cell, which additionally includes a cathode and a fluoride ion electrolyte arranged between the cathode and the anode. At least one of the cathode and the anode reversibly exchange the fluoride ions with the electrolyte during charging or discharging of the electrochemical cell.

An electrode or electrode material or catalyst or catalyst material. The material includes an electrically conducting 3-dimensional (3-D) matrix comprising a plurality of porous regions; an active material, and optionally, a carbon conductivity aid, where the active material is disposed in and/or on at least a portion of the porous regions of the electrically conducting 3-D matrix. The electrode or electrode material or catalyst or catalyst material may be made by contacting an electrically conducting 3-D matrix with additive material dispersed thereon with a liquid. An electrochemical device may comprise the electrode or electrode material or catalyst or catalyst material.

Provided are compositions and methods of malting and using free-standing electrode films for electrodes by a dry process. The process for forming an electrode includes combining a processing additive and an active electrode material or fibrillizable binder to form an electrode precursor material, where the processing additive has a surface roughness and a porosity and intermixing the electrode precursor material. The electrode precursor material may then be combined with the fibrillizable binder or the active electrode material and the fibrillizable binder or the active electrode material is intermixed with the electrode precursor material to form an electrode film material. The electrode film material includes the processing additive, the fibrillizable binder and the active electrode material. The electrode film material is then compressed into an electrode film.

The present application relates to a composite current collector, and a composite electrode and an electrochemical device comprising the same. The composite current collector of the present application comprises an intermediate layer, a first metal layer, a second metal layer, and a through hole. The intermediate layer has a first surface and a second surface opposite to the first surface, the first metal layer is disposed on the first surface, and the second metal layer is disposed on the second surface. The through hole penetrates through the intermediate layer, the first metal layer and the second metal layer, wherein the through hole is filled with an electrically insulated ionic conductor.

The present application relates to a composite current collector, and a composite electrode and an electrochemical device comprising the same. The composite current collector of the present application comprises an intermediate layer, a first metal layer, a second metal layer, and a through hole. The intermediate layer has a first surface and a second surface opposite to the first surface, the first metal layer is disposed on the first surface, and the second metal layer is disposed on the second surface. The through hole penetrates through the intermediate layer, the first metal layer and the second metal layer, wherein the through hole is filled with an electrically insulated ionic conductor.

The present invention relates to a positive electrode active material for a potassium secondary battery, the positive electrode active material according to the present invention is a crystalline material comprising: K; a transition metal; P; and O, and comprises, as a main image, an image indicating a diffraction peak having a relative intensity of 5% or more in a range of Bragg angles (2) of a X-ray diffraction pattern of 14.7 to 15.7, 22.1 to 23.1, 25.5 to 26.5, and 29.7 to 30.8, when the relative intensity of the diffraction peak having the highest intensity is taken as 100% in the powder X-ray diffraction pattern of the material.

An object of the present disclosure is to provide a fluoride ion battery of which power generating elements (a cathode active material layer, a solid electrolyte layer, and an anode active material layer) may be formed by two kinds of members: an electrode layer and a solid electrolyte layer. The present disclosure achieves the object by providing a fluoride ion battery comprising: an electrode layer that includes a first metal element or a carbon element and has capability of fluorination and defluorination; a solid electrolyte layer containing a solid electrolyte material, the solid electrolyte material including a second metal element with lower fluorination potential and defluorination potential than the potentials of the first metal element or the carbon element; and an anode current collector, in this order; and an anode active material layer being not present between the solid electrolyte layer and the anode current collector.

An object of the present disclosure is to provide a fluoride ion battery of which power generating elements (a cathode active material layer, a solid electrolyte layer, and an anode active material layer) may be formed by two kinds of members: an electrode layer and a solid electrolyte layer. The present disclosure achieves the object by providing a fluoride ion battery comprising: an electrode layer that includes a first metal element or a carbon element and has capability of fluorination and defluorination; a solid electrolyte layer containing a solid electrolyte material, the solid electrolyte material including a second metal element with lower fluorination potential and defluorination potential than the potentials of the first metal element or the carbon element; and an anode current collector, in this order; and an anode active material layer being not present between the solid electrolyte layer and the anode current collector.

A secondary battery and its preparation method, the secondary battery having a negative electrode containing a negative current collector and no negative active material; an electrolyte having an electrolyte salt and an organic solvent; a separator; a positive electrode having a positive active material layer containing a positive active material, wherein the positive active material comprises a material having a layered crystal structure; and a battery case used for packaging. Main active component of the secondary battery is the positive active material having a layered crystal structure, which is environmentally-friendly and low in cost; meanwhile, negative active material is not needed by the second battery system, thereby remarkably reducing the weight and cost of the battery and improving the battery energy density. The reaction mechanism adopted by the secondary battery significantly increases the working voltage of the battery and further improves the energy density of the battery.