A wireless sensor device capable of constant operation without replacement of batteries. The wireless sensor device is equipped with a rechargeable battery and the battery is recharged wirelessly. Radio waves received at an antenna circuit are converted into electrical energy and stored in the battery. A sensor circuit operates with the electrical energy stored in the battery, and acquires information. Then, a signal containing the information acquired is converted into radio waves at the antenna circuit, whereby the information can be read out wirelessly.

A porous insulator contains a porous structure, containing a polymer compound having communicating pores, and a solid having a melting point or glass transition temperature lower than that of the polymer compound.

A porous insulator contains a porous structure, containing a polymer compound having communicating pores, and a solid having a melting point or glass transition temperature lower than that of the polymer compound.

An electrode for an electrochemical device has a coated portion in which an active material layer is formed on a current collector; a non-coated portion in which the active material layer is not formed; and a resin layer that is laminated such that the coated portion and a portion of the non-coated portion are covered; wherein: the resin layer has a high-permeability portion having high ion permeability and positioned on the coated portion; a low-permeability portion having low ion permeability and positioned on a portion of the non-coated portion; and a transition portion in which ion permeability decreases from the high-permeability portion side toward the low-permeability portion side and positioned between the high-permeability portion and the low-permeability portion.

A capacitor includes a first metal layer disposed on a wafer or substrate, a first polarized dielectric layer above the first metal layer and comprising a plurality of electrets formed by aligning molecular dipoles throughout a three-dimensional surface area of a polarizable dielectric material during polarization by applying a momentary electric field of positive or negative polarity, a second metal layer disposed on the first polarized dielectric layer to electrically isolate the first polarized dielectric layer, and a second polarized dielectric layer above the second metal layer, the second polarized dielectric layer comprising a plurality of electrets formed by aligning molecular dipoles throughout a three-dimensional surface area of a polarizable dielectric material during polarization by applying a second momentary electric field of opposing polarity. A plurality of alternating polarized dielectric layers and metal layers may be arranged in series to form a stack, with an internal passivation layer disposed between each stack.

A capacitor includes a first metal layer disposed on a wafer or substrate, a first polarized dielectric layer above the first metal layer and comprising a plurality of electrets formed by aligning molecular dipoles throughout a three-dimensional surface area of a polarizable dielectric material during polarization by applying a momentary electric field of positive or negative polarity, a second metal layer disposed on the first polarized dielectric layer to electrically isolate the first polarized dielectric layer, and a second polarized dielectric layer above the second metal layer, the second polarized dielectric layer comprising a plurality of electrets formed by aligning molecular dipoles throughout a three-dimensional surface area of a polarizable dielectric material during polarization by applying a second momentary electric field of opposing polarity. A plurality of alternating polarized dielectric layers and metal layers may be arranged in series to form a stack, with an internal passivation layer disposed between each stack.

A flexible electrode includes: a current collector; an electrode layer positioned at a top of the current collector; a first support layer positioned at a top of the electrode layer; and a second support layer positioned at a bottom of the current collector, wherein each of the first support layer and the second support layer is a conductive coating layer-containing porous polymer substrate including a porous polymer substrate, and a conductive coating layer positioned on a surface of the porous polymer substrate and including a conductive material and a dispersing agent, and the porous polymer substrate is a non-woven web provided with a plurality of polymer fibers and a pore structure interconnected by the plurality of polymer fibers.

A capacity deterioration caused when charging and discharging cycles are repeated in a capacitor that includes a polarizable electrode is suppressed. An electrode foil includes a collector 7 and an electrode active substance layer 3. The electrode active substance layer 3 is formed on a surface of the collector 7. This electrode active substance layer 3 is divided by a dividing portion 32 into a plurality of small regions 31. The electrode foil is applicable for a positive electrode foil, or the positive-electrode foil and a negative-electrode foil, and suppresses a capacity deterioration in an electric double-layer capacitor or in a hybrid capacitor.

A power storage device includes a case, an electrode body, and an electrolyte. The electrode body is located in the case and has a positive electrode, a negative electrode, and a separator located between the positive and negative electrodes. The electrolytefills the case 2. A principal surface of the electrode body is connected to an inner surface of the case.

A power storage device includes a case, an electrode body, and an electrolyte. The electrode body is located in the case and has a positive electrode, a negative electrode, and a separator located between the positive and negative electrodes. The electrolytefills the case 2. A principal surface of the electrode body is connected to an inner surface of the case.