Jeol Ltd.

Other

Power Systems Co., Ltd.

Okamura Laboratory, Inc.

Asahi Glass Company, Limited

Elna Co., Ltd.

Japan Gore-tex Inc.

Kokoku Intech Co., Ltd.

Advanced Capacitor Technologies, Inc.

Kabushiki Kaisha Powersystems

Michio Okamura

Akinori Mogami

Masaaki Yamagishi

Makoto Takeuchi

Takeshi Morimoto

Kazuya Hiratsuka

Hitoshi Nakamura

Minoru Noguchi

Manabu Iwaida

Eisuke Komazawa

Hitoshi Yoshida

Hiroyuki Katsukawa

Kotaro Kobayashi

Atsushi Shimizu

Yusuke Niiori

Masahiko Shinozuka

A capacitor power sourceincluding a plurality of capacitors comprises: an inflection-point voltage detection circuit () for detecting the inflection-point voltage of the capacitor based on a set voltage Vbot; an overvoltage detection circuit () for detecting the overvoltage Vful of the capacitor; and an initialization circuit () for putting charging current of the capacitor into bypass operation using initialization voltage Vini when an initialization mode is selected, wherein charging/discharging control is performed such that a discharging stop signal is generated based on a detection signal of the inflection-point voltage of any one of the plurality of capacitors, a charging stop signal is generated based on a detection signal of the overvoltage of any one of the plurality of capacitors, and an end signal of the initialization charging is generated based on a plurality of bypass operation signals.

Capacitor power source and charging/discharging control apparatus therefor

The invention is intended to reduce expansion proportion of electric double layer capacitors by combining nonporous carbonaceous electrodes produced by a specific method with an electrolyte of a specific structure. Provided is an electric double layer capacitor comprising nonporous carbonaceous electrodes soaked in an organic electrolytic solution, wherein the organic electrolytic solution contains a pyrrolidinium compound salt as a solute, and wherein the carbonaceous electrodes are electrodes obtained by the method comprising a step of obtaining a carbon powder by prebaking a needle coke green powder under an inert atmosphere, baking the prebaked needle coke powder in the presence of alkali hydroxide under an inert atmosphere, and removing the alkali hydroxide; and a step of shaping the carbon powder.

Electric double layer capacitor

The invention provides an electric double-layer capacitor sealed up by a flexible casing material that ensures a release of pressure upon an increasing internal pressure. A pressure release valve () is attached to the flexible casing material. The pressure release valve () comprises a collar airtightly joined to the flexible casing material and a cylindrical portion () connected to the collar, extending out of a capacitor enclosure. The cylindrical portion () comprises an end part () having a self-closing passage () that is opening to the outside only upon a pressure release and is closed up in a normal state, and a channel () in communication with the interior of the capacitor enclosure.

Electric double-layer capacitor

A connection-switched capacitor storage system comprises plural capacitors, parallel monitors connected with the capacitors, respectively, switches for switching the connections of the capacitors from a series combination to a parallel combination or vice versa, and a control portion. The parallel monitors bypass the charging current for the capacitors when the terminal voltages of the capacitors exceed a given voltage, thus limiting increases of the terminal voltages of initializing the terminal voltages of the capacitors to their original level. The control portion controls initialization and switching of the connections of the capacitors. The control portion causes the parallel monitors to initialize the capacitors near the voltage at which the connections of the capacitors are switched by the switches.

Connection-switched capacitor storage system

There is disclosed a carbon material from which an electric double layer capacitor (EDLC) having a large capacitance can be fabricated. First, a carbon material is activated to produce crystallites of graphite-like carbon having interlayer distances of 0.365 to 0.385 nm. Positive and negative plates are fabricated using the crystallites.

Carbon material for electric double layer capacitor, method of producing same, electric double layer capacitor and method of fabricating same

Disclosed is an electric double layer capacitor including polarizable electrodes immersed in an organic electrolyte, wherein a carbon material for forming the polarizable electrode is a carbon material including graphite-like microcrystalline carbon produced by effecting a heat treatment together with at least one of an alkali metal and an alkali metal compound at not less than a temperature at which alkali metal vapor is generated, and an electrostatic capacity is expressed by insertion of ions of a solute of the organic electrolyte into a space between microcrystalline carbon layers of the carbon material. Accordingly, it is possible to achieve an electrostatic capacity and a withstand voltage which exceed those of the conventional electric double layer capacitor based on the activated carbon system.

Electric double layer capacitor and method for producing the same

A capacitor storage system is provided which is simple in structure and can control the charge level according to the use environment and detect a fault, if any. The capacitor storage system comprises: a plurality of capacitors connected in series and producing terminal voltages, respectively, the capacitors developing a total voltage, parallel monitors connected with the capacitors, respectively, for monitoring terminal voltages of the capacitors and for initializing the capacitors, a charging controller for controlling charging of the series-connected capacitors according to the total voltage of the series-connected capacitors, and a charging stop total voltage setter for setting a charging stop total voltage Vm, wherein each of the parallel monitors having a comparator for detecting a predetermined initialization voltage Vini and a bypass circuit for bypassing a charging current of the corresponding capacitor, the bypass circuit receiving an output from the comparator as its control input, the charging controller enables the parallel monitors to perform an operation of initialization, if the initialization voltage is detected from any one of the capacitors, and then stops charging of the series-connected capacitors when the total voltage of the series-connected capacitors reaches the charging stop total voltage Vm.

Capacitor storage system

There is disclosed an electric double-layer capacitor that is adapted for use in an electric vehicle, for example, and uses aluminum collector electrodes. A native oxide film is formed on each aluminum electrode. Hard granular carbon is made to penetrate through the oxide film into each aluminum electrode. The aluminum electrodes are connected with positive and negative polarizing electrodes, respectively, via the granular carbon, thus lowering the contact resistance.

Method of fabricating double-layer capacitor with lower contact resistance

A long-lived, lightweight, and quickly and precisely charged storage capacitor power supply capable of stably supplying electric power to a load. The power supply has a capacitor block consisting of capacitors connected in series, in parallel or in any combination of series and parallel. The power supply further includes a charging circuit for charging the block, a charging power supply connected with the block via the charging circuit, and a charge-limiting circuit. This charge-limiting circuit detects the voltage across the terminals of the block and limits charging of the block if the voltage reaches a given value. One embodiment of the invention further includes a charge-limiting circuit, a full charge-detecting circuit, and a residual electricity-detecting circuit connected in parallel with the block. The charge-limiting circuit senses that the voltage across the terminals of the block exceeds the given value and causes the charging current to bypass the block. The full charge-detecting circuit senses that the charge-limiting circuit is operated and determines that full charge is attained. The residual electricity-detecting circuit finds the residual electric power from the voltage across the terminals of the block. Another embodiment has a first and a second capacitor block. The voltage across the terminals of the first block is detected. The first block is charged from the second block until the detected voltage reaches a given voltage. The first block supplies electric power directly to the load.

Storage capacitor power supply

An electrical storage capacitor system that efficiently initializes itself to its initial state during pause intervals between charging/discharging cycles of operation without providing any special initializing cycles. The capacitor system comprises capacitors connected in series to store electricity, a variation decision means for judging the amount of variation in amount of charge between the capacitors, an operation decision means for judging whether the capacitors are being charged or discharged, and a initializing charging means for charging the capacitors to initialize themselves to their initial state according to the results of decisions made by the variation decision means and by the operation decision means.

Electrical storage capacitor system having initializing function

There is disclosed a power supply system comprising capacitors that are connected switchably via a small number of switches to decrease variations of an output voltage. The switches comprise a series connection switch and first and second sets of switches. A control means controls the first set of switches, the second set of switches, and the series connection switch to switch connection of the capacitors of the first and second sets among a first state in which the first set of capacitors is connected in series with the second set of capacitors, a second state in which the first set of capacitors is connected in parallel with the second set of capacitors, and a third state in which one or more capacitors of the first set are connected in parallel with one or more capacitors of the second set.

Capacitor power supply with switches to decrease variations in output voltage

There is disclosed an electrical storage capacitor system that performs initializing charging and storage charging for energy storage with reduced energy loss. The capacitor system comprises capacitors connected in series, comparators for comparing the voltages developed across the capacitors with a first reference value, voltage limitation means connected in parallel with the capacitors to limit the voltages of the capacitors to a second reference value during initializing charging, and a charger. During initializing charging, the capacitors are charged while operating the voltage limitation means. Storage charging for energy storage is done according to the output signals from the comparators until the voltage of any one of the capacitors reaches the first reference value.

System for charging capacitors connected in series

There is disclosed a capacitor module capable of having an improved packing density and, hence, an improved energy storage density. A capacitor bank using such capacitor modules is also disclosed. Furthermore, an electrical energy storehouse using such capacitor banks is disclosed. Supercapacitor cells connected in series are housed in a box-like capacitor module. A heat dissipator is mounted on an end surface of the module. Parallel monitors connected in parallel with the capacitor cells, respectively, are mounted to the heat dissipator. Such capacitor modules are stacked to form a capacitor bank. The heat-dissipating surface of each module is located on the outside of the bank and exposed. The modules are held in the bank so that they can be taken out of the bank individually. Capacitor banks making a pair are located back-to-back such that their heat-dissipating surface face outward. Pairs of capacitor banks arranged in this way are arranged vertically and horizontally via passages and via space permitting the modules to be taken out.

Capacitor module, bank of such modules, and storehouse housing such banks

An electric double-layer capacitor that is adapted for use in an electric vehicle, for example, and uses aluminum collector electrodes. A native oxide film is formed on each aluminum electrode. Hard granular carbon is made to penetrate through the oxide film into each aluminum electrode. The aluminum electrodes are connected with positive and negative polarizing electrodes, respectively, via the granular carbon, thus lowering the contact resistance.

Growing community of inventors

Kanagawa, Japan

Michio Okamura