Kawasaki Jukogyo Kabushiki Kaisha

National Institute of Advanced Industrial Science and Technology

Tomoaki Takasaki

Tetsuo Sakai

Takashi Mukai

Kazuo Tsutsumi

Kazuya Nishimura

Jinhan Yao

Tsutomu Iwaki

Masateru Nakoji

Makoto Saito

Kasuo Tsutsumi

Disclosed is a nickel positive electrode for a fiber battery having a long life duration, and also being enabling a high output and high capacity to be attained. For this purpose, the nickel positive electrode for a fiber battery is obtained by coating a carbon fiber with nickel, then causing a cathodic polarization in a nickel nitrate bath using the nickel-coated carbon fiber as a cathode, and then immersing the precipitate, which was deposited on the surface of the carbon fiber by the cathodic polarization, in an aqueous caustic alkali solution.

Nickel positive electrode for fiber battery

A secondary battery includes: a fiber negative electrode having a surface on which a negative electrode active material coating is formed, the coating containing a compound of AMXZ; a fiber positive electrode including a positive electrode active material coating containing nickel hydroxide; an aqueous electrolyte solution; and a separator. The negative electrode coating has an uncoated surface. A is selected from the group consisting of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, and Ba; M is selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Nb, Mo, Ru, Pd, Ag, Ta, W, Pr, Sm, Eu, and Pb; X is selected from the group consisting of B, Al, Si, P, S, Ga, and Ge; Z is selected from the group consisting of O, S, N, F, Cl, Br, and I; and 0&#x2266;a&#x2266;6, 1&#x2266;b&#x2266;5, 0&#x2266;c&#x2266;4, 0&#x3c;d&#x2266;12, and 0&#x2266;a/b&#x2266;4.

Negative electrode for use in secondary battery and secondary battery including the same

An object of the present invention is to provide a highly efficient electrical storage device that uses a fiber positive electrode and a fiber negative electrode and in which lithium ion is used as an intercalating species, and to provide a method of fabricating the electrical storage device. The electrical storage device according to the present invention includes: a fiber positive electrode including an electrically conductive fiber, the fiber having a surface on which a positive electrode active material coating is formed, the positive electrode active material coating containing a transition metal oxide represented by a chemical formula 1 which is (LiA)MXO; a fiber negative electrode including an electrically conductive fiber, the fiber having a surface on which a negative electrode active material coating is formed; a separator; and an electrolyte (in the chemical formula 1, A is at least one kind of alkali metal selected from the group consisting of Na, K, Rb, and Cs; M is at least one kind of transition metal selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Nb, Mo, Ru, Pd, Ag, Ta, W, Ce, Pr, Sm, Eu, and Pb; X is at least one kind of typical elements selected from the group consisting of B, Al, Si, P, S, Ga, and Ge; and 0&#x3c;a&#x2266;6, 1&#x2266;b&#x2266;5, 0&#x2266;c&#x2266;4, 0&#x3c;d&#x2266;12, 0&#x2266;a/b&#x2266;4, and 0&#x2266;x&#x2266;0.5).

Electrical storage device including fiber electrode, and method of fabricating the same

Provided is a method for mass manufacturing, at low cost, of a fiber positive electrode for a lithium secondary battery, which has excellent charge/discharge cycle characteristics, and which is capable of charging/discharging with high current density, and a main active material of which is a lithium-doped transition metal oxide. The method includes the steps of: (a) forming a tubular coating of either a transition metal oxide or a transition metal hydroxide on a carbon fiber current collector; and (b) performing, in a lithium ion containing solution in a sealed system under presence of an oxidant or a reductant, heat treatment at 100 to 250&#xb0; C. on the carbon fiber current collector, on which the tubular coating of either the transition metal oxide or the transition metal hydroxide is formed, to obtain a coating of a lithium-doped transition metal oxide on the carbon fiber current collector. Further provided are: a fiber negative electrode for a lithium secondary battery, which has high current density, high energy density, and excellent charge/discharge cycle characteristics, and which can be fabricated in a relatively easy manner; and a method for fabricating the fiber negative electrode. The fiber negative electrode for a lithium secondary battery includes: (c) a carbon fiber current collector; (d) an outer layer which is a tubular composite layer of a Sn oxide and MOformed on the carbon fiber current collector; and (e) an intermediate layer formed of a Sn alloy, which has a lithium occlusion capacity and which is present at an interface between the carbon fiber current collector and the outer layer. The method for fabricating the fiber negative electrode for a lithium secondary battery includes: forming a coating of one of Sn and a Sn alloy, and a coating of at least one kind of metal selected from the group consisting of Fe, Mo, Co, Ni, Cr, Cu, In, Sb, and Bi, on a carbon fiber current collector by an electroplating method; and then performing heat treatment on the carbon fiber current collector under a trace oxygen atmosphere at 350 to 650&#xb0; C. Moreover, the lithium secondary battery includes: the fiber positive electrode and the fiber negative electrode fabricated in the above methods; and an electrolyte.

Fiber electrode for lithium secondary battery, fabrication method therefor, and lithium secondary battery including fiber electrode

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Akashi, Japan

Tomoaki Takasaki