Provided is an internal hybrid electrochemical cell comprising: (A) a pseudocapacitance cathode comprising a cathode active material that contains a conductive carbon material and a porphyrin compound, wherein the porphyrin compound is bonded to or supported by the carbon material to form a redox pair for pseudocapacitance, wherein the carbon material is selected from activated carbon, activated carbon black, expanded graphite flakes, exfoliated graphite worms, carbon nanotube, carbon nanofiber, carbon fiber, a combination thereof; (B) a battery-like anode comprising lithium metal, lithium metal alloy, or a prelithiated anode active material (e.g. prelithiated Si, SiO, Sn, SnO.sub.2, etc.), and (C) a lithium-containing electrolyte in physical contact with the anode and the cathode; wherein the cathode active material has a specific surface area no less than 100 m.sup.2/g which is in direct physical contact with the electrolyte.

A method of producing sizing agent-applied carbon fiber bundles includes a sizing agent application process of immersing a plurality of carbon fiber bundles running side by side in a sizing agent bath, followed by a dry process performed to obtain sizing agent-applied carbon fiber bundles and, to address issues of wrapping of a carbon fiber bundle caused by sticking of a sizing agent solution to a guide roller, the first guide roller for the carbon fiber bundles after being immersed in the sizing agent bath and coming out of a liquid surface of the sizing agent bath is set to have a surface adhesive force of 0.2 N/cm.sup.2 or less.

A method of producing sizing agent-applied carbon fiber bundles includes a sizing agent application process of immersing a plurality of carbon fiber bundles running side by side in a sizing agent bath, followed by a dry process performed to obtain sizing agent-applied carbon fiber bundles and, to address issues of wrapping of a carbon fiber bundle caused by sticking of a sizing agent solution to a guide roller, the first guide roller for the carbon fiber bundles after being immersed in the sizing agent bath and coming out of a liquid surface of the sizing agent bath is set to have a surface adhesive force of 0.2 N/cm.sup.2 or less.

The purpose of the present invention is to provide an electrode active material layer exhibiting excellent mechanical strength. This electrode material for a non-aqueous electrolyte secondary battery includes at least an electrode active material, a carbon-based conductive auxiliary agent, and a binder. The carbon-based conductive auxiliary agent has a linear structure, and includes ultra-fine fibrous carbon having an average fibre diameter of more than 200 nm but not more than 900 nm. The electrode material configures an electrode active material layer in which the maximum tensile strength (.sub.M) in a planar direction and the tensile strength (.sub.T) in an in-plane direction orthogonal to the maximum tensile strength (.sub.M) satisfy relational expression (a), namely .sub.M/.sub.T1.6.

The purpose of the present invention is to provide an electrode active material layer exhibiting excellent mechanical strength. This electrode material for a non-aqueous electrolyte secondary battery includes at least an electrode active material, a carbon-based conductive auxiliary agent, and a binder. The carbon-based conductive auxiliary agent has a linear structure, and includes ultra-fine fibrous carbon having an average fibre diameter of more than 200 nm but not more than 900 nm. The electrode material configures an electrode active material layer in which the maximum tensile strength (.sub.M) in a planar direction and the tensile strength (.sub.T) in an in-plane direction orthogonal to the maximum tensile strength (.sub.M) satisfy relational expression (a), namely .sub.M/.sub.T1.6.

Provided are a graphene-based fiber in which a liquid-crystalline aromatic compound is intercalated into a graphene-based material, a graphene-based carbon fiber obtained by carbonizing the graphene-based fiber, and a method of manufacturing the same.

Provided are a graphene-based fiber in which a liquid-crystalline aromatic compound is intercalated into a graphene-based material, a graphene-based carbon fiber obtained by carbonizing the graphene-based fiber, and a method of manufacturing the same.

Methods are provided for reducing or minimizing the temperature dependence of a pitch feed or fraction for use in carbon fiber production, such as a mesophase pitch feed or fraction or an isotropic pitch feed or fraction. A pitch sample can be characterized to determine a characteristic temperature and a characteristic viscosity for the sample. One or more solvent extraction processes can also be performed on the pitch and/or the extract and raffinate fractions formed by the solvent extraction(s). The resulting raffinate and extract fractions are then used to form a modified pitch fraction with a T.sub.0 value that is lower than the T.sub.0 value of the original pitch. The modified pitch fraction can optionally also have a different .sub.inf value relative to the original pitch.

A fire retardant material comprising a carbon fiber which tensile elasticity is 700 GPa or more, and a fire retardant resin such as polycarbonate.

A fire retardant material comprising a carbon fiber which tensile elasticity is 700 GPa or more, and a fire retardant resin such as polycarbonate.