A subsurface battery comprises an anodic fracture disposed within a subsurface stratum and a cathodic fracture disposed with the subsurface stratum. A first well electrode contacts the anodic fracture and a second well electrode contacts the cathodic fracture.

An alkaline battery includes a negative electrode. The negative electrode includes a negative electrode active material particle. The negative electrode active material particle includes a center part, a covering layer, and island-form layers. The center part includes zinc as a constituent element. The covering layer covers a surface of the center part and includes gallium as a constituent element. The island-form layers are present on a surface of the covering layer and include indium as a constituent element.

An alkaline battery includes a negative electrode. The negative electrode includes a negative electrode active material particle. The negative electrode active material particle includes a center part, a covering layer, and island-form layers. The center part includes zinc as a constituent element. The covering layer covers a surface of the center part and includes gallium as a constituent element. The island-form layers are present on a surface of the covering layer and include indium as a constituent element.

A catalyst consisting of structurally ordered mesoporous carbon containing a transition metal and a method for preparing the same are provided. The method for preparing the catalyst includes forming a mixture of a carbon precursor and structurally ordered mesoporous silica, carbonizing the mixture to form a composite, and removing mesoporous silica from the composite.

A method of: providing an emulsion having a zinc powder and a liquid phase; drying the emulsion to form a sponge; sintering the sponge in an inert atmosphere to form a sintered sponge; heating the sintered sponge in an oxidizing atmosphere to form an oxidized sponge having zinc oxide on the surface of the oxidized sponge; and heating the oxidized sponge in an inert atmosphere at above the melting point of the zinc. A method of: providing an emulsion comprising a zinc powder and a liquid phase; placing the emulsion into a mold, wherein the emulsion is in contact with a metal substrate; and drying the emulsion to form a sponge.

A method of: providing an emulsion having a zinc powder and a liquid phase; drying the emulsion to form a sponge; sintering the sponge in an inert atmosphere to form a sintered sponge; heating the sintered sponge in an oxidizing atmosphere to form an oxidized sponge having zinc oxide on the surface of the oxidized sponge; and heating the oxidized sponge in an inert atmosphere at above the melting point of the zinc. A method of: providing an emulsion comprising a zinc powder and a liquid phase; placing the emulsion into a mold, wherein the emulsion is in contact with a metal substrate; and drying the emulsion to form a sponge.

Provided is a method for preparing a positive electrode active material for a lithium secondary battery, the method comprising: mixing and reacting a nickel source, a cobalt source, and an aluminum source, ammonia water, sucrose, and a pH adjusting agent to prepare a mixed solution; drying and oxidizing the mixed solution to prepare a positive electrode active material precursor; and adding a lithium source to the positive electrode active material precursor and firing them to prepare a positive electrode active material for a lithium secondary battery.

Provided is a process for preparing an electrode comprising an iron active material. The process comprises first fabricating an electrode comprising an iron active material, and then treating the surface of the electrode with water to thereby create an oxidized surface. The resulting iron electrode is preconditioned prior to any charge-discharge cycle to have the assessable surface of the iron active material in the same oxidation state as in discharged iron negative electrodes active material.

Provided is a process for preparing an electrode comprising an iron active material. The process comprises first fabricating an electrode comprising an iron active material, and then treating the surface of the electrode with water to thereby create an oxidized surface. The resulting iron electrode is preconditioned prior to any charge-discharge cycle to have the assessable surface of the iron active material in the same oxidation state as in discharged iron negative electrodes active material.

A coated nickel hydroxide powder that has a cobalt compound coating having improved uniformity and adhesion properties on the surface of particles thereof and is therefore suitable for a positive electrode active material of an alkaline secondary battery is obtained by coating the surface of nickel hydroxide particles with a cobalt compound, and has a transmittance ratio of 30% or higher as determined by (A−B.sub.max)/(B.sub.0−B.sub.max). The transmittance A (coated nickel hydroxide powder), the transmittance B.sub.0 (nickel hydroxide powder), or the transmittance B.sub.max (nickel hydroxide powder and cobalt compound containing cobalt in an amount corresponding to the amount of cobalt contained in the coating) can be determined by measuring the transmittance of a tubular transparent cell after shaking the tightly-closed transparent cell containing each powder for a certain time and then taking the contents out of the transparent cell.