Abstract: A battery includes: an electrode group including an air electrode and a negative electrode that are stacked with a separator interposed therebetween; and a container housing the electrode group together with an alkaline electrolyte liquid. The air electrode includes a catalyst for an air electrode. This catalyst for an air electrode is a catalyst for an air electrode including an oxide containing at least bismuth (Bi), ruthenium (Ru), sodium (Na), and oxygen, and Na/(Ru+Bi+Na) representing an atomic ratio of the sodium to a sum of the bismuth, the ruthenium, and the sodium is 0.126 or more and 0.145 or less.

Abstract: A battery 2 includes: a container 10; and an electrode group 6 housed in the container 10 together with an alkaline electrolyte liquid 4. The electrode group 6 includes a nickel electrode 14 as a positive electrode and a negative electrode 12 that are combined with a separator 8 interposed therebetween. The nickel electrode 14 includes a positive electrode core and a positive electrode mixture permeated in the positive electrode core. The positive electrode mixture contains nickel hydroxide that is a positive electrode active material. The nickel hydroxide contains a sulfate salt, and a weight rate of a S component contained in the sulfate salt to a Ni component in the nickel hydroxide is 0.28% or more and 1.50% or less.

Abstract: A battery includes: an electrode group including an air electrode and a negative electrode that are stacked with a separator interposed therebetween; and a container housing the electrode group together with an alkaline electrolyte liquid. The air electrode includes a catalyst for an air secondary battery, and this catalyst for an air secondary battery includes a pyrochlore bismuth-ruthenium composite oxide having a full width at half maximum of a diffraction peak corresponding to a (222) face obtained by a powder X-ray diffraction method using CuK? rays as X-rays, of 0.350 deg or larger and 0.713 deg or smaller.

Abstract: A battery includes: an electrode group including an air electrode and a negative electrode that are stacked with a separator interposed therebetween; and a container housing the electrode group together with an alkaline electrolyte liquid. The air electrode includes a catalyst for an air electrode. This catalyst for an air electrode is a catalyst for an air electrode including an oxide containing at least bismuth (Bi), ruthenium (Ru), sodium (Na), and oxygen, and Na/(Ru+Bi+Na) representing an atomic ratio of the sodium to a sum of the bismuth, the ruthenium, and the sodium is 0.126 or more and 0.145 or less.

Abstract: An air electrode catalyst for an air secondary battery includes a pyrochlore-type composite oxide having two or more crystal structures having a different amount of oxygen. A battery, according to some embodiments, includes an electrode group including an air electrode and a negative electrode stacked with a separator therebetween, and a container accommodating the electrode group along with an alkali electrolyte solution, wherein the air electrode includes the air electrode catalyst. The air electrode catalyst may have a pyrochlore-type composite oxide having a crystal structure represented by Bi2Ru2O6.92 and a crystal structure represented by Bi2Ru2O7.33.

Abstract: A battery includes an electrode group including an air electrode and a negative electrode stacked with a separator therebetween, and an accommodating bag accommodating the electrode group along with an alkali electrolyte solution. The air electrode includes a catalyst for an air secondary battery. This catalyst for an air secondary battery is produced by a method for producing a catalyst for an air secondary battery, the method including a precursor preparation step of preparing a bismuth-ruthenium oxide precursor, a calcination step of calcining the bismuth-ruthenium oxide precursor obtained in this precursor preparation step to form a bismuth-ruthenium oxide, and a nitric acid treatment step of immersing the bismuth-ruthenium oxide obtained by this calcination step in a nitric acid aqueous solution.

Abstract: A nickel-hydrogen secondary battery includes an electrode group comprising a separator, a positive electrode, and a negative electrode, and the positive electrode contains a positive electrode active material including a base particle comprising a nickel hydroxide particle containing Mn in solid solution and a conductive layer comprising a Co compound and covering the surface of the base particle, wherein the X-ray absorption edge energy of Mn detected within 6500 to 6600 eV by measurement with an XAFS method is 6548 eV or higher.

Abstract: A battery includes an electrode group including an air electrode and a negative electrode stacked with a separator therebetween, and an accommodating bag accommodating the electrode group along with an alkali electrolyte solution. The air electrode includes a catalyst for an air secondary battery. This catalyst for an air secondary battery is produced by a method for producing a catalyst for an air secondary battery, the method including a precursor preparation step of preparing a bismuth-ruthenium oxide precursor, a calcination step of calcining the bismuth-ruthenium oxide precursor obtained in this precursor preparation step to form a bismuth-ruthenium oxide, and a nitric acid treatment step of immersing the bismuth-ruthenium oxide obtained by this calcination step in a nitric acid aqueous solution.

Abstract: An air electrode catalyst for an air secondary battery includes a pyrochlore-type composite oxide having two or more crystal structures having a different amount of oxygen. A battery, according to some embodiments, includes an electrode group including an air electrode and a negative electrode stacked with a separator therebetween, and a container accommodating the electrode group along with an alkali electrolyte solution, wherein the air electrode includes the air electrode catalyst. The air electrode catalyst may have a pyrochlore-type composite oxide having a crystal structure represented by Bi2Ru2O6.92 and a crystal structure represented by Bi2Ru2O7.33.

Abstract: A nickel-hydrogen secondary battery includes an electrode group comprising a separator, a positive electrode, and a negative electrode, and the positive electrode contains a positive electrode active material including a base particle comprising a nickel hydroxide particle containing Mn in solid solution and a conductive layer comprising a Co compound and covering the surface of the base particle, wherein the X-ray absorption edge energy of Mn detected within 6500 to 6600 eV by measurement with an XAFS method is 6548 eV or higher.

Abstract: A multi-phase hydrogen storage alloy comprising a hexagonal Ce2Ni7 phase and a hexagonal Pr5Co19 phase, where the Ce2Ni7 phase abundance is ?30 wt % and the Pr5Co19 phase abundance is ?8 wt % and where the alloy comprises a mischmetal where Nd in the mischmetal is <50 at % or a multi-phase hydrogen storage alloy comprising one or more rare earth elements, a hexagonal Ce2Ni7 phase and a hexagonal Pr5Co19 phase, where the Ce2Ni7 phase abundance is from about 30 to about 72 wt % and the Pr5Co19 phase abundance is ?8 wt % have improved electrochemical performance. The alloys are useful in an electrode in a metal hydride battery, a fuel cell or a metal hydride air battery.

Abstract: A nickel-hydrogen secondary battery includes an electrode group including a separator, a positive electrode and a negative electrode, the positive electrode includes a positive electrode active material, the positive electrode active material includes a composite particle including a compound of Co and a compound of Ni, and the ratio R represented by A/B satisfies a relationship of R?0.3, when the amount of jumping in the X-ray absorption fine structure spectrum of the Co in 7600 to 7800 eV and the amount of jumping in the X-ray absorption fine structure spectrum of the Ni in 8300 to 8500 eV obtained by measurement according to a conversion electron yield method are defined as A and B, respectively.

Abstract: A multi-phase hydrogen storage alloy comprising a hexagonal Ce2Ni7 phase and a hexagonal Pr5Co19 phase, where the Ce2Ni7 phase abundance is ?30 wt % and the Pr5Co19 phase abundance is ?8 wt % and where the alloy comprises a mischmetal where Nd in the mischmetal is <50 at % or a multi-phase hydrogen storage alloy comprising one or more rare earth elements, a hexagonal Ce2Ni7 phase and a hexagonal Pr5Co19 phase, where the Ce2Ni7 phase abundance is from about 30 to about 72 wt % and the Pr5Co19 phase abundance is ?8 wt % have improved electrochemical performance. The alloys are useful in an electrode in a metal hydride battery, a fuel cell or a metal hydride air battery.

Abstract: A multi-phase hydrogen storage alloy comprising a hexagonal Ce2Ni7 phase and a hexagonal Pr5Co19 phase, where the Ce2Ni7 phase abundance is ?30 wt % and the Pr5Co19 phase abundance is ?8 wt % and where the alloy comprises a mischmetal where Nd in the mischmetal is <50 at % or a multi-phase hydrogen storage alloy comprising one or more rare earth elements, a hexagonal Ce2Ni7 phase and a hexagonal Pr5Co19 phase, where the Ce2Ni7 phase abundance is from about 30 to about 72 wt % and the Pr5Co19 phase abundance is ?8 wt % have improved electrochemical performance. The alloys are useful in an electrode in a metal hydride battery, a fuel cell or a metal hydride air battery.

Abstract: A nickel-hydrogen secondary battery includes an electrode group comprising a separator, a positive electrode, and a negative electrode, and the positive electrode contains a positive electrode active material including a base particle comprising a nickel hydroxide particle containing Mn in solid solution and a conductive layer comprising a Co compound and covering the surface of the base particle, wherein the X-ray absorption edge energy of Mn detected within 6500 to 6600 eV by measurement with an XAFS method is 6548 eV or higher.

Abstract: A nickel-hydrogen secondary battery includes an electrode group including a separator, a positive electrode and a negative electrode, the positive electrode includes a positive electrode active material, the positive electrode active material includes a composite particle including a compound of Co and a compound of Ni, and the ratio R represented by A/B satisfies a relationship of R?0.3, when the amount of jumping in the X-ray absorption fine structure spectrum of the Co in 7600 to 7800 eV and the amount of jumping in the X-ray absorption fine structure spectrum of the Ni in 8300 to 8500 eV obtained by measurement according to a conversion electron yield method are defined as A and B, respectively.

Abstract: A multi-phase hydrogen storage alloy comprising a hexagonal Ce2Ni7 phase and a hexagonal Pr5Co19 phase, where the Ce2Ni7 phase abundance is ?30 wt % and the Pr5Co19 phase abundance is 8 wt % and where the alloy comprises a mischmetal where Nd in the mischmetal is <50 at % or a multi-phase hydrogen storage alloy comprising one or more rare earth elements, a hexagonal Ce2Ni7 phase and a hexagonal Pr5Co19 phase, where the Ce2Ni7 phase abundance is from about 30 to about 72 wt % and the Pr5Co19 phase abundance is ?8 wt % have improved electrochemical performance. The alloys are useful in an electrode in a metal hydride battery, a fuel cell or a metal hydride air battery.

Abstract: A negative electrode for alkaline storage battery using a hydrogen-absorbing alloy includes fluorinated oil and a surface active agent.

Abstract: An alkaline storage battery has a negative electrode using a hydrogen-absorbing alloy represented by a general formula Ln1-xMgxNiyAz wherein Ln is at least one element selected from rare-earth elements including Y, Ca, Zr, and Ti, A is at least one element selected from Co, Fe, Mn, V, Cr, Nb, Al, Ga, Zn, Sn, Cu, Si, P and B, and 0.15?x?0.30, 0<z?1.5, and 2.8?y+z?4.0 are satisfied. The hydrogen-absorbing alloy has a hexagonal system crystal structure or a rhombohedral system crystal structure as its main phase and has a subphase of line which average number of not less than 50 nm in thickness existing in the range of 10 ?m×10 ?m in the cross section of the main phase is 3 or less.

Abstract: A hydrogen-absorbing alloy for alkaline storage battery which is produced by a rapid cool using a rapid quenching method and whose component is represented by a general formula Ln1-xMgxNia-b-cAlbZc is used for a negative electrode of an alkaline storage battery.