A secondary battery according to an embodiment includes a container, an electrolytic solution, a cathode and an anode, and a flow mechanism. The container includes an opening on a bottom surface thereof. The electrolytic solution is disposed in the container. The cathode and the anode are disposed in the electrolytic solution. The flow mechanism includes a generation part that is connected to the container via the opening and generates a gas bubble(s) in the container through the opening, and that causes the electrolytic solution to flow. A protrusion part that is positioned at an edge part of the opening and extends in upward and downward directions is disposed on the bottom surface.

An alkaline battery comprises an anode, a cathode, a separator disposed between the anode and the cathode, a barrier layer disposed between the anode and the cathode, and an electrolyte in fluid communication with the anode, the cathode, and the separator. The barrier layer is at least one of: an organic polymer film or a porous inorganic layer or combinations thereof.

The invention relates to a starved metal hydride battery. The battery is characterized in that the battery further comprises adding of oxygen gas or hydrogen gas or hydrogen peroxide or a combination thereof in order to rebalance the electrodes and replenish the electrolyte by reactions with the electrode materials.

The invention relates to a starved metal hydride battery. The battery is characterized in that the battery further comprises adding of oxygen gas or hydrogen gas or hydrogen peroxide or a combination thereof in order to rebalance the electrodes and replenish the electrolyte by reactions with the electrode materials.

A negative electrode used in a nickel metal hydride secondary battery includes a negative electrode core body and a negative electrode mixture carried on the negative electrode core body. The negative electrode mixture includes hydrogen storage alloy powder which is an aggregate of hydrogen storage alloy particles, a binder, and a thickener. The hydrogen storage alloy particles have a volume mean particle size of 40 μm or less and a concentration of chlorine of not less than 180 ppm to not more than 780 ppm.

A negative electrode used in a nickel metal hydride secondary battery includes a negative electrode core body and a negative electrode mixture carried on the negative electrode core body. The negative electrode mixture includes hydrogen storage alloy powder which is an aggregate of hydrogen storage alloy particles, a binder, and a thickener. The hydrogen storage alloy particles have a volume mean particle size of 40 μm or less and a concentration of chlorine of not less than 180 ppm to not more than 780 ppm.

A nickel-containing hydroxide particle covered with cobalt capable of preventing cracks and fissures in the particle and fine powder from being generated due to having an excellent particle strength is provided. The nickel-containing hydroxide particle covered with cobalt, including a covering layer containing cobalt oxyhydroxide formed on a nickel-containing hydroxide particle, wherein an average particle strength is 65.0 MPa or more and 100.0 MPa or less for a particle diameter with a cumulative volume percentage of 50% by volume (D50) of 10.0 μm or larger and 11.5 μm or smaller.

A nickel-containing hydroxide particle covered with cobalt capable of preventing cracks and fissures in the particle and fine powder from being generated due to having an excellent particle strength is provided. The nickel-containing hydroxide particle covered with cobalt, including a covering layer containing cobalt oxyhydroxide formed on a nickel-containing hydroxide particle, wherein an average particle strength is 65.0 MPa or more and 100.0 MPa or less for a particle diameter with a cumulative volume percentage of 50% by volume (D50) of 10.0 μm or larger and 11.5 μm or smaller.

There is provided a secondary zinc battery including: a unit cell including; a positive-electrode plate including a positive-electrode active material layer and a positive-electrode collector; a negative-electrode plate including a negative-electrode active material layer containing zinc and a negative-electrode collector; a layered double hydroxide (LDH) separator covering or wrapping around the entire negative-electrode active material layer; and an electrolytic solution. The positive-electrode collector has a positive-electrode collector tab extending from one edge of the positive-electrode active material layer, and the negative-electrode collector has a negative-electrode collector tab extending from the opposite edge of the negative-electrode active material layer and beyond a vertical edge of the LDH separator. The unit cell can thereby collects electricity from the positive-electrode collector tab and the negative-electrode collector tab. The LDH separator has at least two continuous closed edges, provided that an edge, adjacent to the negative-electrode collector tab, of the LDH separator is open.

There is provided a secondary zinc battery including: a unit cell including; a positive-electrode plate including a positive-electrode active material layer and a positive-electrode collector; a negative-electrode plate including a negative-electrode active material layer containing zinc and a negative-electrode collector; a layered double hydroxide (LDH) separator covering or wrapping around the entire negative-electrode active material layer; and an electrolytic solution. The positive-electrode collector has a positive-electrode collector tab extending from one edge of the positive-electrode active material layer, and the negative-electrode collector has a negative-electrode collector tab extending from the opposite edge of the negative-electrode active material layer and beyond a vertical edge of the LDH separator. The unit cell can thereby collects electricity from the positive-electrode collector tab and the negative-electrode collector tab. The LDH separator has at least two continuous closed edges, provided that an edge, adjacent to the negative-electrode collector tab, of the LDH separator is open.