Batteries having hybrid electrode configurations are disclosed herein. In one embodiment, a battery comprises an electrode assembly. The electrode assembly comprises a first cathode including a first cathode active material, a second cathode including a second cathode active material different from the first cathode active material, a first anode disposed between the first cathode and the second cathode, a first separator interposed between the first cathode and the first anode, and a second separator interposed between the second cathode and the first anode.

Provided is a positive electrode active material that achieves improvement in load resistance such as rate performance and output resistance when used as a positive electrode active material in a lithium-ion secondary battery, achieves improvement in powder properties, has a short manufacturing cycle time, and is low in cost. The positive electrode active material is manufactured by a first step of forming a first mixture by separately pulverizing a compound containing one or more elements selected from magnesium, calcium, zirconium, lanthanum, and barium; a compound containing halogen and an alkali metal; and a fluoride containing one or more metals selected from nickel, aluminum, manganese, titanium, vanadium, iron, and chromium, and then mixing them with metal oxide powder; and a second step of performing heating at a temperature higher than or equal to 700° C. and lower than or equal to 950° C.

The present disclosure provides a composite wherein NaCl nanoparticles are uniformly dispersed on reduced graphene oxide (rGO), a positive electrode active material including the same, a sodium secondary battery including the same, and a method for preparing the same. The positive electrode active material according to the present disclosure has a structure wherein NaCl nanoparticles are uniformly dispersed on rGO in a one-step process through chemical self-assembly. Therefore, the positive electrode active material according to the present disclosure exhibits superior electrochemical properties with high capacity because the small NaCl particles are dispersed uniformly and is economically favorable because the preparation process is simple.

A positive electrode active substance for the non-aqueous secondary battery is provided. The positive electrode active substance includes a metal or a metal compound including the metal element M.sup.1 exhibiting a conversion reaction and/or a reverse conversion reaction, and an amorphous metal oxide of the metal element M.sup.2. M.sup.2 includes at least one metal element selected from the group consisting of V, Cr, Mo, Mn, Ti, and Ni.

A method for forming a positive electrode active material of a lithium ion secondary battery is provided. The method for forming a positive electrode active material includes a first step of placing a first container in which a mixture of a lithium oxide, a fluoride, and a magnesium compound are put, in a heating furnace, a second step of providing an atmosphere including oxygen in an inside of the heating furnace, and a third step of heating the inside of the heating furnace. The third step is performed after the first step and the second step are performed. Preferably, an atmosphere including oxygen is provided in the heating furnace before the inside of the heating furnace is heated. More preferably, the fluoride is lithium fluoride and the magnesium compound is magnesium fluoride.

An amorphous oxide-based positive electrode active material that is a production material of a positive electrode for an all-solid secondary battery, wherein the amorphous oxide-based positive electrode active material (i) comprises an alkali metal selected from Li and Na; a second metal selected from Co, Ni, Mn, Fe, Cr, V, Cu, Ti, Zn, Zr, Nb, Mo, Ru and Sn; an ionic species selected from phosphate ion, sulfate ion, borate ion, silicate ion, aluminate ion, germanate ion, nitrate ion, carbonate ion and halide ion; and an oxygen atom (except for the oxygen atom constituting the ionic species); (ii) contains at least an amorphous phase; and (iii) is a production material of a positive electrode with a thickness of 20 μm or more.

An electrolyte element (10) comprises a perforated sheet (11) of non-reactive metal such as an aluminium-bearing ferritic steel, and a non-permeable ceramic layer (16b) of sodium-ion-conducting ceramic bonded to one face of the perforated sheet (11) by a porous ceramic sub-layer (16a). The perforated sheet (11) may be of thickness in the range 50 μm up to 500 μm, and the thickness of the non-permeable ceramic layer (16b) may be no more than 50 μm, for example 20 μm or 10 μm. Thus the electrolyte properties are provided by the non-permeable thin layer (16b) of ceramic, while mechanical strength is provided by the perforated sheet (11). The electrolyte element (10) may be used in a rechargeable molten sodium-metal halide cell, in particular a sodium/nickel chloride cell (20). It makes cells with increased power density possible.

A fluoride ion secondary battery, comprising: a positive electrode layer, a solid electrolyte layer, and a negative electrode layer, wherein the positive electrode layer comprises a positive electrode active material; the positive electrode active material comprises a composite fluoride comprising copper and a fluoride; the solid electrolyte comprises BaCaF.sub.4; the negative electrode layer comprises a negative electrode active material, a conductive aid, and a solid electrolyte; the negative electrode active material comprises a lanthanoid fluoride doped with the alkaline earth metal fluoride; the conductive aid comprises a carbon material, the solid electrolyte contained in the negative electrode layer comprises at least one of BaCaF.sub.4 and SrCaF.sub.4; and the lanthanoid fluoride doped with the alkaline earth metal fluoride forms a composite with the carbon material.

A negative electrode plate, a lithium-ion battery and an apparatus are disclosed. The negative electrode plate includes a negative electrode current collector, a negative electrode active material layer including a negative electrode active material and disposed on at least one surface of the negative electrode current collector, and a lithium-replenishing layer disposed on a surface of the negative electrode active material layer away from the negative current collector. The negative electrode plate can effectively ameliorate the problem of plate heating, and channels formed by the lithium-replenishing region and the gap region can enable the lithium-ion battery to be effectively impregnated with the electrolyte after electrolyte injection is performed to the lithium-ion battery, thereby improving the energy density of the battery while also improving the service life and kinetic performance of the battery.

Provided is an anode-free metal halide battery. The metal halide battery comprises a current collector, an electrolyte, and a cathode. The current collector comprises a passivation layer of an electrically insulating material. The passivation layer allows metal ion transport. The electrolyte comprises an ion-conducting material and is in contact with the current collector and the cathode. The cathode comprises a metal halide salt incorporated into an electrically conductive metal.