Provided is a positive electrode active material for a lithium ion secondary battery having favorable cycle characteristics and high capacity. A covering layer containing aluminum and a covering layer containing magnesium are provided on a superficial portion of the positive electrode active material. The covering layer containing magnesium exists in a region closer to a particle surface than the covering layer containing aluminum is. The covering layer containing aluminum can be formed by a sol-gel method using an aluminum alkoxide. The covering layer containing magnesium can be formed as follows: magnesium and fluorine are mixed as a starting material and then subjected to heating after the sol-gel step, so that magnesium is segregated.

Provided are a vehicle-use energy storage apparatus, a vehicle-use discharge system, a discharge control method, and a vehicle-use energy storage device each capable of ensuring a sufficient amount of electricity as an amount of electricity used during a normal use time while ensuring an amount of electricity which is reserved as spare electricity, and possessing a sufficient charge-discharge cycle. According to an aspect of the present invention, there is provided a vehicle-use energy storage apparatus including an energy storage device having a negative electrode including a negative active material which contains: a first active material made of a carbon material; and a second active material having a higher oxidation potential than the carbon material and having a higher capacity per volume than the carbon material. In performing discharging of the energy storage device, a main discharge reaction occurs in the first active material during a normal time, and the main discharge reaction occurs in the second active material during an emergency time.

Provided are a vehicle-use energy storage apparatus, a vehicle-use discharge system, a discharge control method, and a vehicle-use energy storage device each capable of ensuring a sufficient amount of electricity as an amount of electricity used during a normal use time while ensuring an amount of electricity which is reserved as spare electricity, and possessing a sufficient charge-discharge cycle. According to an aspect of the present invention, there is provided a vehicle-use energy storage apparatus including an energy storage device having a negative electrode including a negative active material which contains: a first active material made of a carbon material; and a second active material having a higher oxidation potential than the carbon material and having a higher capacity per volume than the carbon material. In performing discharging of the energy storage device, a main discharge reaction occurs in the first active material during a normal time, and the main discharge reaction occurs in the second active material during an emergency time.

3-D magnesium voltaic cells have a magnesium anode coated on multiple opposing surfaces with a continuous protective/electrolyte layer that is ionically conductive and electronically insulating. The resulting protected 3-D magnesium anode is coated on multiple opposing surfaces with a continuous cathode layer that is electronically and ionically conductive, and includes a magnesium storage medium. Suitable magnesium anodes, in particular, magnesium foam anodes, can be made by pulsed galvanostatic deposition of magnesium on a copper substrate. The protective layer can be formed by electropolymerization of a suitable methylacrylate ester. The continuous cathode layer can be a slurry cathode having powders of an electronic conductor and a reversible magnesium storage component suspended in a magnesium electrolyte solution.

A polymer solid electrolyte for an electrochemical device including a magnesium electrode as a negative electrode, the polymer solid electrolyte including a Mg polymer salt containing Mg.sup.2+ and an anionic polymer having an anionic functional group and a coordinating functional group, and the polymer solid electrolyte having Mg ion conductivity.

Disclosed is a flexible battery made of a cathode comprising printable graphite, the cathode positioned on a first side of a paper; an anode comprising aluminum on a second side of the paper; an aqueous electrolyte comprising water and an aluminum halide, the aqueous electrolyte saturated within the paper; and an encapsulating film surrounding the anode and cathode.

An electrochemical cell includes a negative electrode including a metal, metal alloy, or an electrode active material that reversibly intercalates and de-intercalates cations; a positive electrode including (i) an electrode active material that reversibly intercalates and de-intercalates cations or anions, or (ii) an inert host that reversibly catalyzes an external reactant; a separator between the negative electrode and the positive electrode; and an electrolyte including one or more alcohol-based solvents, with one or more salts. The solvents may include methanol, ethanol, isopropanol, triglycerol, 2,2,2-trifluoroethanol, an organic small molecule or macromolecule that contain at least one hydroxyl (OH) group, or a combination thereof. The electrochemical cell may include a mixture of multiple alcohol-based solvents or a mixture of the one or more alcohol-based solvents with water, mixed at select ratios. The electrochemical cell may include one or more additives having a concentration range between 0.01% to 20% by weight.

Provided is a lithium secondary battery including: an aluminum anode configured to occlude and release lithium ions; a cathode configured to occlude and release lithium ions; and an electrolyte solution, in which the aluminum anode is formed of an aluminum-containing metal, and the electrolyte solution contains an electrolyte, an organic solvent, and an additive.

Cells for use in electrochemical devices as well as electrochemical cells and their use in producing electricity, hydrogen, or both electricity and hydrogen simultaneously. The cells include an electrode comprising a liquid phase material, comprising at least one of gallium and indium, disposed on a metal solid comprising aluminum. The liquid phase material can disrupt an oxide layer on the metal solid such that the aluminum can take part in an electrochemical reaction.

A secondary battery includes: a positive electrode having a positive-electrode current collector and a positive-electrode active-material layer; a negative electrode having a negative-electrode current collector and a negative-electrode active-material layer; a electrolyte; and an insulating tape covering a portion of the positive electrode. Furthermore, the positive-electrode current collector has an exposed section that the positive-electrode active-material layer is not disposed. In addition, at least a portion of the exposed section is covered with the insulating tape; the insulating tape has a substrate material layer and an adhesive layer; and the adhesive layer includes an adhesive agent and an insulating inorganic material.