1810results about "Hybrid capacitor current collectors" patented technology

Composite electrodes including carbon nanofibers (fibrils) and an electrochemically active material are provided for use in electrochemical capacitors. The fibril composite electrodes exhibit high conductivity, improved efficiency of active materials, high stability, easy processing, and increase the performance of the capacitor. A method for producing the composite electrodes for use in electrochemical capacitors is also provided.

Thin-film micro-electrochemical energy storage cells (MEESC) such as microbatteries and double-layer capacitors (DLC) are provided. The MEESC comprises two thin layer electrodes, an intermediate thin layer of a solid electrolyte and optionally, a fourth thin current collector layer; said layers being deposited in sequence on a surface of a substrate. The MEESC is characterized in that the substrate is provided with a plurality of through cavities of arbitrary shape, with high aspect ratio. By using the substrate volume, an increase in the total electrode area per volume is accomplished.

An electrical storage device of the present invention is characterized in that a positive electrode, a negative electrode, a lithium electrode, and an electrolyte capable of transferring lithium ion is included, the lithium electrode is arranged to be out of direct contact with the negative electrode, and lithium ion can be supplied to the negative electrode by flowing a current between the lithium electrode and the negative electrode through an external circuit. With the above characteristic, problems such as non-uniform carrying of lithium ion to the negative electrode, shape-change of a cell, and temperature increase of an electrolytic solution under incomplete sealing of a cell and the like can be easily solved. A using method of the electrical storage device is characterized in that, by using the lithium electrode as a reference electrode, the positive electrode potential and negative electrode potential can be measured, and the potential of the positive or negative electrode can be controlled when the electrical storage device is charged or discharged. Therefore, the potentials of the positive electrode and negative electrode can be monitored, thereby it can be easily determined whether deterioration of the electrical storage device is caused by the positive electrode or the negative electrode. Also, it is possible to control the device with the potential difference between the negative electrode and reference electrode, that is, the negative potential. In addition, when characteristics deteriorate such as the internal resistance increase, an appropriate amount of lithium ion can be supplied to the negative electrode and/or positive electrode by the lithium electrode.

There is provided an organic electrolyte capacitor having electrodes on current collectors that have holes penetrating the front and rear surfaces, in which electrode materials formed an the through-holes of the current collectors seldom fall off and high energy density and high power density can be obtained. The organic electrolyte capacitor includes positive electrodes, negative electrodes and an electrolyte capable of transferring lithium ions, in which the positive electrodes contain a substance capable of carrying lithium ions and/or anions reversibly as a positive electrode active material, the negative electrodes contain a substance capable of carrying lithium ions as a negative electrode active material, the positive and negative electrodes possess the positive or negative electrode active material layers on an electrode substrate that has conductive layers made of conductive materials on current collectors, which have through-holes, and the negative electrodes carry lithium electrochemically.

An asymmetric electrochemical capacitor has at least a larger capacitance electrode and a smaller capacitance electrode, with an electrolyte therebetween. The larger capacitance electrode has a larger absolute capacitance than the smaller capacitance electrode. The capacitor thus has an overall capacitance which is approximately the absolute capacitance of the smaller capacitance electrode. The electrodes may be made of different materials, with the larger capacitance electrode made of the material having a larger specific capacitance. The larger capacitance electrode may thus be the same physical size as or smaller than the smaller capacitance electrode.

The quick recharge energy storage device has a sufficient capacity due to the combination of a micro-battery and at least one micro-supercapacitor connected between two terminals of an integrated circuit. The integrated circuit, powered by the micro-battery, monitors high-speed (less than one second) charge of the micro-supercapacitors from an external energy source. The micro-supercapacitor can be connected in parallel with the micro-battery so as to subsequently recharge the micro-battery during the necessary time. The micro-battery provides a sufficient energy capacity, while the micro-supercapacitors allow high recharging speeds compatible with various applications (smart cards, smart labels, micro-system power supply, etc . . . ). The micro-battery and micro-supercapacitors are preferably formed on the same substrate, either side by side or stacked. Series connection of several micro-supercapacitors provides sufficient voltage for charging the micro-battery.

The present invention is characterized by obtaining a high charge/discharge capacity upon high rate charging/discharging in a hybrid capacitor having characteristics of both an electric double layer capacitor and a lithium-ion secondary battery. Specifically, the present invention is a capacitor comprising: a positive electrode 1 composed of a polarizable electrode containing activated carbon; a negative electrode 2 containing as an anode active material a carbon material capable of inserting/extracting lithium ion; and a nonaqueous electrolyte containing lithium ion, wherein a charge cutoff potential for the negative electrode 2 is within the range of 0.15 to 0.25 V (vs. Li/Li⁺).

The present invention relates to an electric double layer capacitor comprised of carbonaceous electrodes enclosed in polymer housing, using conductive polymer current collectors intrinsically bonded to both the electrodes and the enclosure, and a method for constructing the same. The present invention also relates to bipolar stacks of electric double layer capacitor cells and a method for producing the same.

A method of formation and charge of a negative polarizable electrode of an electric double layer capacitor. The method can be used for manufacturing of high capacitance capacitors utilizing the energy of the electric double layer. The methods achieve hydrogen evolution on carbonaceous materials using very negative potentials. The methods provide an EDL capacitor, employing an aqueous electrolyte, with improved specific energy. The methods may also ensure the hermeticity of the capacitor. The methods include pretreating the electric double layer capacitor by keeping the negative polarizable electrode at a desired minimum potential prior to use. Desirably, the minimum potential ranges from about -0.25 to about -1.2 V vs. a reference hydrogen electrode.

An energy storage device cell includes: a capacitor cathode including a capacitor cathode collector foil, and a capacitor cathode electrode layer formed on one face of the capacitor cathode collector foil and containing microparticles of activated carbon; a first separator; a common anode including an anode collector foil having a through-hole, and an anode electrode layer formed on one face of the anode collector foil; a second separator; and a battery cathode including a battery cathode collector foil, and a battery cathode electrode layer formed on one face of the battery cathode collector foil and containing particles of a lithium-containing metal compound. The first separator is sandwiched by the capacitor cathode electrode layer and the anode electrode layer. The second separator is sandwiched by the anode collector foil and the battery cathode electrode layer.

A power storage device having a small thickness is manufactured. A manufacturing method of the power storage device includes: forming a first layer and a second layer over a first substrate; forming a first insulating layer, a positive electrode and a negative electrode over the second layer; forming a solid electrolyte layer over the first insulating layer, the positive electrode, and the negative electrode; forming a sealing layer to cover the solid electrolyte layer; forming a planarization film and a support over the sealing layer; separating the first layer and the second layer from each other so that the second layer, the positive electrode, the negative electrode, the solid electrolyte layer, the sealing layer, the planarization film, and the support are separated from the first substrate; attaching the separated structure to a second substrate which is flexible; and separating the support from the planarization film.

Provided is a method for manufacturing a power storage device in which a crystalline silicon layer including a whisker-like crystalline silicon region is formed as an active material layer over a current collector by a low-pressure CVD method in which heating is performed using a deposition gas containing silicon. The power storage device includes the current collector, a mixed layer formed over the current collector, and the crystalline silicon layer functioning as the active material layer formed over the mixed layer. The crystalline silicon layer includes a crystalline silicon region and a whisker-like crystalline silicon region including a plurality of protrusions which project over the crystalline silicon region. With the protrusions, the surface area of the crystalline silicon layer functioning as the active material layer can be increased.

An energy storage stack of at least two surface-mediated cells (SMCs) internally connected in parallel or in series. The stack includes: (A) At least two SMC cells, each consisting of (i) a cathode comprising a porous cathode current collector and a cathode active material; (ii) a porous anode current collector; and (iii) a porous separator disposed between the cathode and the anode; (B) A lithium-containing electrolyte in physical contact with all the electrodes, wherein the cathode active material has a specific surface area no less than 100 m²/g in direct physical contact with the electrolyte to receive lithium ions therefrom or to provide lithium ions thereto; and (C) A lithium source. This new-generation energy storage device exhibits the highest power densities of all energy storage devices, much higher than those of all the lithium ion batteries, lithium ion capacitors, and supercapacitors.

<heading lvl="0">Abstract of Disclosure</heading> A method of making a double layer capacitor consists of the steps of: impregnating each of a plurality of carbon preforms with a metal; forming a plurality of current collector foils, each of the plurality of current collector foils having a tab portion and a paddle portion; forming a plurality of electrodes by positioning one of the plurality of carbon preforms against respective paddle portions of each of the plurality of current collector foils, wherein each of the plurality of electrodes comprises one of the plurality of current collector foils and one of the plurality of carbon preforms; stacking each of the plurality of electrodes such that tab portions of adjacent ones of the plurality of current collector foils are offset, thereby forming an electrode stack; interposing respective porous separator portions between each of the plurality of electrodes, wherein the porous separator portions function as electrical insulators between the adjacent ones of the plurality of electrodes preventing electrical shorting against each other; applying a modest constant pressure against the electrode stack; saturating the electrode stack with an electrolytic solution; and maintaining the electrode stack immersed within the electrolytic solution.

Provided is an anode active material for energy storage devices capable of electrochemically inserting and extracting lithium ions and production method thereof, an electrode structure including the active material and flake graphite, and an energy storage device using the electrode structure as an anode. The anode active material includes secondary particles that are aggregates of 10-300 nm primary particles containing silicon as a main component. The primary particles each include, as a surface layer, a composite metal oxide layer containing at least one or more metal elements selected from at least Al, Zr, Mg, Ca, and La and Li.

A method of manufacturing a cylindrical high voltage supercapacitor. An anode and a cathode are provided. At least one bipolar electrode is interposed between the anode and the cathode, and a separator is intervened in each pair of the above electrodes. The anode, the cathode, the bipolar electrode and the separator, as placed in the above order, are wound concentrically into a roll, so as to form the cylindrical high voltage supercapacitor.

Disclosed herein are electrodes having a multi-layered structure, including at least two active material layers formed on an electrode current collector or including at least two active material layers formed on an electrode current collector, wherein at least two active material layers are stacked thereon, and a supercapacitor comprising the same. The electrodes including at least two active material layers configured of the activated carbon layer having large specific surface area and the graphene layer having excellent electrical conductivity in order to reduce the internal resistance and stacked in a multi layered structure are manufactured and the supercapacitor includes the electrodes to increase capacitance due to the large specific surface area of the activated carbon and reduce the internal resistance due to excellent electrical conductivity of the graphene, thereby making it possible to improve the capacitance and electrical conductivity.

To provide an electric storage device whose negative electrode can be doped with lithium ions in a short time and whose resistance can be lowered. An electric storage device including a unit that is obtained by alternately stacking a positive-electrode sheet 9 and a negative-electrode sheet 10 with a separator 3 interposed therebetween, the positive electrode sheet 9 including a positive-electrode active material layer 1 and a positive-electrode charge collector 4, and the negative electrode sheet 10 including a negative-electrode active material layer 2 and a negative-electrode charge collector 5, in which a foil, an etching foil, or a porous lath foil is used as the positive-electrode charge collector 4 and the negative-electrode charge collector 5, a cut is made in a coating area of the positive-electrode active material layer 1 and the negative-electrode active material layer 2, and a lithium supply source is disposed so as to be opposed to the negative electrode sheet 10 of the unit.

A current collector for use in a capacitor having an aqueous or non-aqueous electrolyte, such as an aqueous sulfuric acid electrolyte. The conductive basis of the current collector may be manufactured from a number of conductive metals but, preferably, is comprised of lead or a lead alloy. The portion of the conductive basis that will be in contact with the electrolyte is provided with a protective layer that is created by deposition of one or more layers of one or more protective coating materials thereto. Each protective coating material is comprised of at least a conductive carbon powder and a polymer binder that is resistant to the electrolyte. Preferably, but not essentially, the protective coating material(s) are applied to the conductive basis in the form of a paste, which is subsequently subjected to a solvent evaporation step and a thermal treatment step. The resulting protective layer is also substantially devoid of pores through which the electrolyte can permeate.

An electrode includes a substrate having a carbon nanostructure (CNS) disposed thereon and a coating including an active material conformally disposed about the carbon nanostructure and the substrate. The electrode is used in a hybrid capacitor-battery having a bifunctional electrolyte capable of energy storage.

An ultracapacitor or hybrid capacitor includes an electrically non-conductive rigid or semi-rigid porous honeycomb structure (12) having cells extending along a common direction and having an average density per unit area within in a plane perpendicular to the common direction exceeding 15.5 per square centimeter, desirably formed of a material that is stable at temperatures of 300° or more, such that high temperatures processing can be used to help ensure high purity of the final product. The material may desirably be an oxide or non-oxide ceramic, such as cordierite, silicon nitride, alumina, aluminum titanate, zircon, glass, or glass-ceramic.

The present invention relates to a film-type micro-supercapacitor and a manufacturing method thereof including a method for manufacturing an electrode film by using graphene or graphene oxide, a method for forming a two-dimensional electrode by separating a graphene or graphene oxide electrode film into two independent electrodes through patterning, a method for forming an in-plane structure of the two-dimensional electrode, a method for forming a current collector on an electrode, and a method for manufacturing a supercapacitor with a micrometer thickness by supplying an electrolyte to the two-dimensional electrode. The film-type micro-supercapacitor can efficiently replace or support the battery in the field of very small electronic devices such as microelectromechanical systems (MEMS), paper-like displays, or smartcards requiring a very small power supply.