10505results about "Hybrid/EDL manufacture" patented technology

A low temperature chemical route to efficiently produce nanomaterials is described. The nanomaterials are synthesized by intercalating ions into layered compounds, exfoliating to create individual layers and then sonicating to produce nanotubes, nanorods, nanoscrolls and/or nanosheets. It is applicable to various different layered inorganic compounds (for example, bismuth selenides/tellurides, graphite, and other metal complexes, particularly transition metal dichalcogenides compounds including oxygen, sulfur, tellurium or selenium).

A flexible, asymmetric electrochemical cell comprising: (A) A sheet of graphene paper as first electrode comprising nano graphene platelets having a platelet thickness less than 1 nm, wherein the first electrode has electrolyte-accessible pores; (B) A thin-film or paper-like first separator and electrolyte; and (C) A thin-film or paper-like second electrode which is different in composition than the first electrode; wherein the separator is sandwiched between the first and second electrode to form a flexible laminate configuration. The asymmetric supercapacitor cells with different NGP-based electrodes exhibit an exceptionally high capacitance, specific energy, and stable and long cycle life.

A secondary hybrid aqueous energy storage device includes an anode electrode, a cathode electrode which is capable of reversibly intercalating sodium cations, a separator, and a sodium cation containing aqueous electrolyte, wherein an initial active cathode electrode material comprises an alkali metal containing active cathode electrode material which deintercalates alkali metal ions during initial charging of the device.

The invention relates to an aqueous fluoropolymer, and preferably polyvinylidene fluoride (PVDF), composition for manufacturing electrodes for use in non-aqueous-type electrochemical devices, such as batteries and electric double layer capacitors. The composition contains aqueous PVDF binder, and one or more powdery electrode-forming materials. In one embodiment, the composition is free of fluorinated surfactant In another embodiment, one or more fugitive adhesion promoters are added. The electrode formed from the composition of the invention exhibits interconnectivity and irreversibility that is achieved from the use of aqueous PVDF binder.

An electrochemical device comprising a chemically modified graphene material is disclosed. An ultracapacitor comprising a chemically modified graphene material is disclosed, along either with a method of making an ultracapacitor, the method comprising forming two electrodes, wherein at least one of the two electrodes comprises a graphene material, and positioning each of the two electrodes such that each is in contact with an opposing side of a separator and a current collector

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.

The energy content of supercapacitor is determined by its capacitance value and working voltage. To attain a high capacitance and a high voltage, several pieces of electrodes and separators are spirally wound with edge sealing to form a bipolar supercapacitor in cylindrical, oval or square configuration. While the winding operation effectively provides a large surface area for high capacitance, the bipolar packaging instantly imparts a unitary roll a minimum working voltage of 5V on using an organic electrolyte. The bipolar roll is a powerful building block for facilitating the assembly of supercapacitor modules. Using containers with multiple compartments, as many bipolar rolls can be connected in series, in parallel or in a combination of the two connections to fabricate integrated supercapacitors with high energy density as required by applications.

A polarizable electrode for an electric double layer capacitor includes an activated carbon powder, and a binder material mixed with the activated carbon. The amount of water contained in the polarizable electrode is 1500 ppm or less with respect to the weight of the polarizable electrode.

In activated carbon obtained by subjecting a carbonaceous material to an activation treatment, the overall content of alkali metals is set at 100 ppm or less, or the overall content of heavy metals is set at 20 ppm or less and the overall content of alkali metals is set at 200 ppm or less. In cases where such activated carbon is used as a raw material in electronic devices, the formation of dendrites by the reductive deposition of alkali metals or heavy metals tends not to occur, so that problems such as short-circuiting or the like tend not to arise, and a good rate of self-discharge retention is shown.

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.

The invention provides a multi-element composite nano-material for a super capacitor, and a preparation method of the nano-material. The nano-material comprises a carbon material, metal oxide and conducting polymer, and components of the nano-material can be two or more than two materials. By the aid of the characteristics such as fine electrical conductivity, long cycle life and high specific surface area of the carbon material, high pseudo-capacitance of the metal oxide and low internal resistance, low cost and high operating voltage of the conducting polymer, different types of electrode materials generate synergistic effects, advantages are mutually combined, shortcomings are mutually weakened, the energy storage characteristics of an electric double-layer capacitor and a pseudo-capacitor are simultaneously made full use of, a composite electrode material with high power density, fine circulating stability and higher energy density is prepared, and the multi-element composite nano-material is excellent in comprehensive performance when used for an electrode of the super capacitor, has the advantages of simple preparation process, short cycle, low cost and the like, and is suitable for large-scale industrial production.

A dry process-based electro-chemical device and method for making a self-supporting dry electrode film for use therein is disclosed. Cost effective manufacture of electrochemical devices such as batteries, capacitors, and fuel cells is enabled.

Synthesis process for new particles of Li4Ti5O12, Li(4-alpha)ZalphaTi5O12 or Li4ZbetaTi(5-beta)O12, preferably having a spinel structure, wherein beta is greater than 0 and less than or equal to 0.5 (preferably having a spinel structure), alpha representing a number greater than zero and less than or equal to 0.33, Z representing a source of at least one metal, preferably chosen from the group made up of Mg, Nb, Al, Zr, Ni, Co. These particles coated with a layer of carbon notably exhibit electrochemical properties that are particularly interesting as components of anodes and/or cathodes in electrochemical generators.

The invention discloses a method for preparing graphene aerogel and graphene/ metallic oxide aerogel. The method is characterized in that graphite oxide aqueous solution serves as a raw material, alcohol serves as a cross-linking agent, a precursor solution is obtained through the simple mixing and dispersing processes, the hydrothermal method is adopted, the freeze drying method or a supercritical drying method is adopted, and then the graphene aerogel is obtained . The graphene/ metallic oxide aerogel can be prepared by adding metallic oxide into the polymeric precursor solution. On one hand, the graphene vinyl aerogel material has the characteristic of the graphene aerogel, and on the other hand, the graphene vinyl aerogel material can have the physicochemical characteristic of the metallic oxide. In addition, the aerogel material has a large specific surface and good electrical conductivity, can directly serve as a supercapacitor electrode, and has large specific capacity, good rate capability and cycling stability. The materials used in the method are low in cost, the industrial process is simple, and the method is friendly to the environment.

Particular aspects provide capacitors, and particularly ultracapacitors, comprising molecules suitable to substantially increasing the capacitance of the capacitor, and methods for making same Particular aspects provide ultracapacitors that include nanoparticles optionally coated with molecules, such as polymer electrolytes. Certain aspects provide an energy storage device or capacitor, comprising at least three layers sealed in a fluid-tight covering, wherein a first layer comprises at least one electrolytic polymer molecule of positive charge and at least one nanoparticle; a second dielectric layer comprising at least one insulative polymer; a third layer comprising at least one electrolytic polymer molecule of negative charge and at least one nanoparticle. In certain aspects, the electrolytic polymer of the first layer comprises at least one high charge density polymer electrolyte of positive charge, and wherein the electrolytic polymer of the third layer comprises at least one high charge density polymer electrolyte of negative charge.

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.

The invention provides a preparation method for three-dimensional porous graphene for a supercapacitor. The preparation method comprises steps as follows: ultrasonically dispersing graphene oxide; fully mixing with a strong alkali solution; pre-drying until a surface is humidified; then activating at a vacuum environment at 120 to 180 DEG C or in protective gas atmosphere at 180 to 1200 DEG C under a high temperature; and etching the surface of the graphene to obtain a three-dimensional porous structure through high-temperature strong alkali and stream, so as to improve a specific surface area of a graphene material. According to the preparation method, activated graphene oxide is reduced through chemical reduction and high-temperature reduction methods, so as to improve a performance of activated graphene. The activated graphene and an adhesive are mixed to prepare into electrode paste based on a certain mass ratio, and the electrode paste is loaded on a conductive current collector to prepare into a supercapacitor electrode, so that a degree of agglomeration of the graphene on a pole piece can be further reduced, and a high electrochemical performance can be obtained.

A process for producing a supercapacitor electrode, comprising: (a) preparing a graphene dispersion containing an optional blowing agent; (b) depositing the dispersion onto a supporting substrate to form a wet layer; (c) removing the liquid medium from the wet layer to form a dried layer of graphene material; (d) heat treating the dried layer at a temperature from 80° C. to 3,200° C. to induce volatile gas molecules from the non-carbon elements or to activate the blowing agent for producing a layer of solid graphene foam having a physical density from 0.01 to 1.7 g/cm³ and a specific surface area from 50 to 3,300 m²/g; and (e) impregnating the foam with an electrolyte to form a layer of pre-impregnated graphene foam, which is compressed to form the electrode. This process leads to a supercapacitor having a large electrode thickness, high active mass loading, high tap density, and exceptional energy density.

An apparatus, system, and method are provided for a vertical two-terminal nanotube device configured to capture and generate energy, to store electrical energy, and to integrate these functions with power management circuitry. The vertical nanotube device can include a column disposed in an anodic oxide material extending from a first distal end of the anodic oxide material to a second distal end of the anodic oxide material. Further, the vertical nanotube device can include a first material disposed within the column, a second material disposed within the column, and a third material disposed between the first material and the second material. The first material fills the first distal end of the column and extends to the second distal end of the column along inner walls of the column. The second material fills the first distal end of the column and extends to the second distal end of the column within the first material. Both the first material and the second material are exposed at the first distal end of the column.

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.

A polymer gel electrolyte includes an electrolyte solution composed of a plasticizer with at least two carbonate structures on the molecule and an electrolyte salt, in combination with a matrix polymer. Secondary batteries made with the polymer gel electrolyte can operate at a high capacitance and a high current, have a broad service temperature range and a high level of safety, and are thus particularly well-suited for use in such applications as lithium secondary cells and lithium ion secondary cells. Electrical double-layer capacitors made with the polymer gel electrolyte have a high output voltage, a large output current, a broad service temperature range and excellent safety.