A printed energy storage device includes a first electrode, a second electrode, and a separator between the first and the second electrode. At least one of the first electrode, the second electrode, and the separator includes frustules, for example of diatoms. The frustules may have a uniform or substantially uniform property or attribute such as shape, dimension, and/or porosity. A property or attribute of the frustules can also be modified by applying or forming a surface modifying structure and/or material to a surface of the frustules. A membrane for an energy storage device includes frustules. An ink for a printed film includes frustules.

An electrode comprises graphene, titanium dioxide and a binder, the binder configured to facilitate the binding together of the graphene and titanium dioxide to form the electrode.

An electrode comprises graphene, titanium dioxide and a binder, the binder configured to facilitate the binding together of the graphene and titanium dioxide to form the electrode.

The present invention provides an electrode material comprising at least one of metal compound powder and carbon powder, the powder having an average particle size of 50 μm or less and an activation energy E.sub.α of 0.05 eV or less. Further, the powder preferably has hopping conduction characteristics at room temperature of 25° C. Furthermore, the powder preferably has an amount of oxygen defects of 1×10.sup.18 cm.sup.−3 or more. Still further, the powder preferably has a carrier density of 1×10.sup.18 cm.sup.−3 or more. Due to above structure, there can be provided an electrode material having a high storage capacity and a high charge/discharge efficiency.

The present invention provides an electrode material comprising at least one of metal compound powder and carbon powder, the powder having an average particle size of 50 μm or less and an activation energy E.sub.α of 0.05 eV or less. Further, the powder preferably has hopping conduction characteristics at room temperature of 25° C. Furthermore, the powder preferably has an amount of oxygen defects of 1×10.sup.18 cm.sup.−3 or more. Still further, the powder preferably has a carrier density of 1×10.sup.18 cm.sup.−3 or more. Due to above structure, there can be provided an electrode material having a high storage capacity and a high charge/discharge efficiency.

A slurry capable of strongly adhering an active material to a surface of a current collector even when heat-dried at high temperature is provided. The slurry according to an embodiment of the present invention contains at least an active material and a fibrous adhesion-imparting component and has a property expressed by Equation (1) below: (Peel strength P.sub.60)/(peel strength P.sub.80≥0.8) (1), where the peel strength P.sub.60 is peel strength determined as follows: a laminate of a copper foil/a solidified product/an acrylic plate is prepared by applying the slurry to a surface of a copper foil having a thickness of 15 μm and drying at 60° C. for 30 minutes to produce a solidified product with a length of 25 mm, a width of 150 mm, and a thickness of 100 μm, bonding an acrylic plate to a surface of the solidified product with a double-sided adhesive tape and reciprocating a 1-kg weight 5 times; the peel strength is determined when a copper foil edge is peeled at an angle of 90° and a speed of 100 mm/min in a state where the acrylic plate side of the resulting laminate is fixed; and the peel strength P.sub.80 is peel strength determined by the same method as the peel strength P.sub.60 except for changing the drying conditions to 80° C. for 22.5 minutes.

A method for fabricating an electrode for an energy storage device is provided. The method includes heating a mixture of solvent and materials for use as energy storage media; adding active material to the mixture; adding dispersant to the mixture to provide a slurry; coating a current collector with the slurry; and calendaring the coating of slurry on the current collector to provide the electrode.

A method for fabricating an electrode for an energy storage device is provided. The method includes heating a mixture of solvent and materials for use as energy storage media; adding active material to the mixture; adding dispersant to the mixture to provide a slurry; coating a current collector with the slurry; and calendaring the coating of slurry on the current collector to provide the electrode.

An objective of the present disclosure is to provide a method of producing metal compound particle group for an electricity storage device electrode that has an improved rate characteristic, the metal compound particle group, and an electrode formed of the metal compound particle group. The method of producing metal compound particle group applied for an electrode of an electricity storage device, the method includes a step of combining a precursor of metal compound particle with a carbon source to obtain a first composite material, a step of producing the metal compound particle by heat processing the first composite material under a non-oxidizing atmosphere to obtain a second composite material having the metal compound particle combined with carbon, and a step of eliminating carbon by heat processing the second composite material under an oxygen atmosphere to obtain the metal compound particle group having the metal compound particle coupled in a three-dimensional mesh structure.

An objective of the present disclosure is to provide a method of producing metal compound particle group for an electricity storage device electrode that has an improved rate characteristic, the metal compound particle group, and an electrode formed of the metal compound particle group. The method of producing metal compound particle group applied for an electrode of an electricity storage device, the method includes a step of combining a precursor of metal compound particle with a carbon source to obtain a first composite material, a step of producing the metal compound particle by heat processing the first composite material under a non-oxidizing atmosphere to obtain a second composite material having the metal compound particle combined with carbon, and a step of eliminating carbon by heat processing the second composite material under an oxygen atmosphere to obtain the metal compound particle group having the metal compound particle coupled in a three-dimensional mesh structure.