A miniature electrochemical cell having a volume of less than 0.5 cc is described. The cell has a casing of first and second ceramic substrates that are hermetically secured to each other to provide an internal space housing an electrode assembly. First and second conductive pathways extend through the ceramic substrates. The pathways have respective inner surfaces that are conductively connected to the respective anode and cathode current collectors and respective outer surfaces that provide for connection to a load. An electrolyte in the internal space of the housing activates the electrode assembly.

An embodiment is directed to a solid state electrolyte-comprising Li or Li-ion battery cell, comprising an anode electrode, a cathode electrode with an areal capacity loading that exceeds around 3.5 mAh/cm.sup.2, an ionically conductive separator layer that electrically separates the anode and cathode electrodes, and one or more solid electrolytes ionically coupling the anode and the cathode, wherein at least one of the one or more solid electrolytes or at least one solid electrolyte precursor of the one or more solid electrolytes is infiltrated into the solid state Li or Li-ion battery cell as a liquid.

An embodiment is directed to a solid state electrolyte-comprising Li or Li-ion battery cell, comprising an anode electrode, a cathode electrode with an areal capacity loading that exceeds around 3.5 mAh/cm.sup.2, an ionically conductive separator layer that electrically separates the anode and cathode electrodes, and one or more solid electrolytes ionically coupling the anode and the cathode, wherein at least one of the one or more solid electrolytes or at least one solid electrolyte precursor of the one or more solid electrolytes is infiltrated into the solid state Li or Li-ion battery cell as a liquid.

A lithium ion battery according to the present invention comprises a positive electrode, a negative electrode, a positive electrode lead that is connected to the positive electrode, an insulation tape that covers the positive electrode lead, and an electrolyte solution. The insulation tape comprises a base material layer that is mainly composed of an organic material, and a filler layer that is provided on the base material layer; the filler layer contains an oxide compound of an alkaline earth metal; and the electrolyte solution contains fluorine.

This secondary battery is provided with an electrode body formed by laminating a positive electrode and a negative electrode with a separator interposed therebetween. The separator includes a first layer and a second layer having a lesser thermal shrinkage than the first layer, and has a tubular part that is formed in a tubular shape and that constitutes the outermost surface of the electrode body. The tubular part, of the separator, that constitutes the outermost surface of the electrode body has a tape stuck thereto in at least one end portion in the axial direction, the tape pressing the one end portion in the axial direction from one side to the other side in the lamination direction of the electrode body.

An electrochemical device includes electrode plates and a separation layer formed on a surface of an electrode plate. The separation layer includes a porous layer formed on the surface of the electrode plate. The porous layer includes nanofibers. It takes 15 seconds or less for an electrolytic solution to infiltrate into the separation layer. The separation layer exhibits functions of a separator. Therefore, the electrochemical device achieves at least a relatively high energy density without using a stand-alone separator.

An electrochemical device includes electrode plates and a separation layer formed on a surface of an electrode plate. The separation layer includes a porous layer formed on the surface of the electrode plate. The porous layer includes nanofibers. It takes 15 seconds or less for an electrolytic solution to infiltrate into the separation layer. The separation layer exhibits functions of a separator. Therefore, the electrochemical device achieves at least a relatively high energy density without using a stand-alone separator.

A negative electrode material includes a composite of a silicon-based material (1), a polymer (2), and carbon nanotubes (3), where the polymer (2) contains a first group and a second group, the first group is chemically bonded to the carbon nanotubes (3), and the second group is chemically bonded to the silicon-based material (1). Both the carbon nanotubes (3) and the polymer (2) containing two groups are applied to surfaces of particles of the silicon-based material (1). The two groups of the polymer (2) are chemically bonded to the silicon-based material (1) and the carbon nanotubes (3) respectively, so that bonding force between the silicon-based material (1) and the carbon nanotubes (3) is enhanced and a uniform carbon nanotube (3) coating layer is formed. This can significantly improve conductive performance of the silicon-based material (1), thereby improving cycling performance and rate performance of an electrochemical apparatus.

A negative electrode material includes a composite of a silicon-based material (1), a polymer (2), and carbon nanotubes (3), where the polymer (2) contains a first group and a second group, the first group is chemically bonded to the carbon nanotubes (3), and the second group is chemically bonded to the silicon-based material (1). Both the carbon nanotubes (3) and the polymer (2) containing two groups are applied to surfaces of particles of the silicon-based material (1). The two groups of the polymer (2) are chemically bonded to the silicon-based material (1) and the carbon nanotubes (3) respectively, so that bonding force between the silicon-based material (1) and the carbon nanotubes (3) is enhanced and a uniform carbon nanotube (3) coating layer is formed. This can significantly improve conductive performance of the silicon-based material (1), thereby improving cycling performance and rate performance of an electrochemical apparatus.

An energy storage apparatus includes an energy storage device, a spacer disposed in a predetermined direction of the energy storage device, and an adhesive layer which is disposed between the energy storage device and the spacer and bonds the energy storage device and the spacer to each other. The spacer includes a first protruding portion which is disposed at a position adjacent to the adhesive layer in an intersecting direction which intersects the predetermined direction and projects toward the energy storage device and a second protruding portion which is disposed at a position different from the first protruding portion and projects toward the energy storage device and has a protrusion height lower than that of the first protruding portion.