A positive electrode for a lithium secondary battery includes a positive electrode current collector; a lower positive electrode active material layer disposed on at least one surface of the positive electrode current collector; and an upper positive electrode active material layer disposed on the lower positive electrode active material layer, wherein the lower positive electrode active material layer includes 90% or more of a sphere-type carbonaceous conductive material as a conductive material, the upper positive electrode active material layer includes 90% or more of a needle-type carbonaceous conductive material as a conductive material, and the content of the conductive material contained in the lower positive electrode active material layer is larger than the content of the conductive material contained in the upper positive electrode active material layer.

A bio-electrode composition includes (A) an ionic material and (B) a silicon material powder. The component (A) is a polymer compound containing a repeating unit-a having a structure selected from an ammonium salt, a sodium salt, a potassium salt, and a silver salt of any of fluorosulfonic acid, fluorosulfonimide, and N-carbonyl-fluorosulfonamide. Thus, the present invention provides a bio-electrode composition capable of forming a living body contact layer for a bio-electrode that is excellent in electric conductivity and biocompatibility, is light-weight, can be manufactured at low cost, and can control significant reduction in the electric conductivity even when the bio-electrode is wetted with water or dried; a bio-electrode including a living body contact layer formed of the bio-electrode composition; and a method for manufacturing the bio-electrode.

Methods of manufacturing cathode active materials, including preparing a solution of a hygroscopic species and a reactive oxygen species, heating the solution at a temperature that is less than about 400° C. for a time sufficient for a precipitate of the cathode active material to form, and collecting the cathode active material. The cathode active materials can be used to prepare cathodes that evolve little or no oxygen during operation. The cathodes can be economically incorporated into batteries that can provide high energy density.

A copolymer, including a structural unit represented by Chemical Formula 1, a structural unit represented by Chemical Formula 2, or a combination thereof:

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wherein R.sub.1, R.sub.2, R.sub.3, X.sub.1, X.sub.2, and Ar.sub.1 are as provided herein.

Provided is a Li.sup.+battery comprising an anode comprising an anode active material comprising a plurality of transition metal (TM.sub.1)-substituted binary transition metal (TM.sub.2) oxide nanocrystals, a cathode in electrical communication with the anode, a separator between the anode and the cathode, and an electrolyte in contact with the anode and the cathode. The anode active material, in a lithiated state, is characterized by a three-dimensional network of the TM.sub.1 and nanoparticles of Li.sub.2O and nanoparticles of the TM.sub.2, both types of nanoparticles distributed throughout the network. In a delithiated state, the anode active material is characterized by the network of the TM.sub.1 and nanoparticles of an oxide of the TM.sub.1 and nanoparticles of an oxide of the TM.sub.2, both types of nanoparticles distributed throughout the network. The TM.sub.1-substituted binary TM.sub.2 oxide may be characterized by a ratio of TM.sub.2/TM.sub.1 of at least about 5.

A rechargeable manganese battery includes: (1) a first electrode including a porous, conductive support; (2) a second electrode including a catalyst support and a catalyst disposed over the catalyst support; and (3) an electrolyte disposed between the first electrode and the second electrode to support reversible precipitation and dissolution of manganese at the first electrode and reversible evolution and oxidation of hydrogen at the second electrode.

Provided are a positive electrode for a metal-sulfur battery, a method of manufacturing the same, and a metal-sulfur battery including the same. The positive electrode comprises a positive electrode active material layer including carbon material and sulfur-containing material. In the positive electrode active material layer, a region in which the sulfur-containing material is densified and a region in which the carbon material is densified are arranged separately. By providing a positive electrode capable of exhibiting a high utilization rate of sulfur, it is possible to provide a metal-sulfur battery having high capacity and stable life characteristics.

A lead-acid battery provided with a negative electrode plate, a positive electrode plate, and an electrolyte solution. The negative electrode plate includes a negative current collector and a negative electrode material. When it is defined in a log differential pore volume distribution of the negative electrode material that a) a region having a pore size of 1 to 3 μm is a P region, b) a region having a pore size of 6 to 15 μm is a Q region, c) a maximum value of the log differential pore volume in the P region is P, and d) a maximum value of the log differential pore volume in the Q region is Q, after initial degradation, during use, or after 1220 cycles in a light-load life test in which charge and discharge of constant current discharge at 25 A for one minute and constant voltage charge at 2.47 V/cell and an upper limit current of 25 A for ten minutes are repeated at a test temperature of 75° C., the log differential pore volume distribution of the negative electrode material has a peak p corresponding to the maximum value P in the P region and a peak q corresponding to the maximum value Q in the Q region, and the maximum value P and the maximum value Q satisfy 0.25≤P/(P+Q)≤0.63.

Energy storage devices, battery cells, and batteries of the present technology may include a first current collector including a material characterized by a maximum corrosion current in an aqueous electrolyte below or about 2 mA/cm.sup.2. The batteries may include a cathode material coupled with the first current collector. The batteries may include a second current collector, and may include an anode material coupled with the second current collector. The batteries may also include an aqueous electrolyte characterized by a pH greater than or about 14.

The present invention relates to a catalyst for solid polymer fuel cells in which catalyst particles including platinum are supported on a carbon powder carrier. The invention provides a catalyst for solid polymer fuel cells in which the ratio of zerovalent platinum to platinum present on the surfaces of the catalyst particles is 80% or more and 100% or less. In the platinum catalyst, excellent durability is exhibited in an environment of operating a solid polymer fuel cell, and the amount of platinum eluted at the time of immersing the catalyst in a predetermined sulfuric acid solution is lower as compared to conventional platinum catalysts. The invention provides a catalyst for solid polymer fuel cells excellent in both initial activity and durability.