Patent Application
20160087460
The present invention relates to ultra-capacitor structures and more particularly to ultra-capacitor structures with multiple ultra-capacitor cells, and methods thereof.
Modern electronic devices make use of numerous electronic components requiring different voltages or currents for operation. For instance, memory components, central processing units, and radio transceivers may all operate at different nominal voltages or currents. In addition, modern electronic devices and components thereof can require different voltages or currents for different periods of time. In one example, a mobile electronic device can have a radio transceiver requiring different voltages or currents during radio reception, radio standby, or radio transmission. In another example, the mobile electronic device can have a camera component requiring different voltages or currents during camera flash or camera focusing.
Typically, electronic devices, such as mobile electronic devices, have a battery with a single nominal voltage, and multiple different voltages or currents are achieved through the use of direct current to direct current (DC-DC) conversion circuits. However, DC-DC conversion circuits are inefficient, dissipating energy to the surrounding environment in the form of heat or radiation. The dissipated energy can adversely impact performance of the electronic device, for example, due to increased temperature from thermal dissipation, and decreased energy capacity for powering the electronic devices.
The shortcomings of the prior art are overcome, and additional advantages are provided, through the provision, in one aspect, of a structure. The structure includes: an ultra-capacitor structure having multiple ultra-capacitor cells; and a switching mechanism, the switching mechanism being operable to selectively connect different electrical interconnect configurations of the multiple ultra-capacitor cells of the ultra-capacitor structure to provide any one of a plurality of different voltages or currents to at least one electrical load, and to selectively control charging of the multiple ultra-capacitor cells using energy from at least one battery.
In another aspect, an electronic system is presented. The electronic system includes: an ultra-capacitor structure having multiple ultra-capacitor cells; at least one battery; and a switching mechanism, the switching mechanism being operable to selectively connect different electrical interconnect configurations of the multiple ultra-capacitor cells of the ultra-capacitor structure to provide any one of a plurality of different voltages or currents to at least one electrical load, and to selectively control charging of the multiple ultra-capacitor cells using energy from the at least one battery.
In a further aspect, a method is presented. The method includes: obtaining an ultra-capacitor structure having multiple ultra-capacitor cells; connecting different electrical interconnect configurations of the multiple ultra-capacitor cells of the ultra-capacitor structure to provide any one of a plurality of different voltages or currents to at least one electrical load; and charging the ultra-capacitor structure using energy from at least one battery.
Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention.
One or more aspects of the present invention are particularly pointed out and distinctly claimed as examples in the claims at the conclusion of the specification. The foregoing and other objects, features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
Aspects of the present invention and certain features, advantages, and details thereof, are explained more fully below with reference to the non-limiting examples illustrated in the accompanying drawings. Descriptions of well-known materials, fabrication tools, processing techniques, etc., are omitted so as not to unnecessarily obscure the invention in detail. It should be understood, however, that the detailed description and the specific examples, while indicating aspects of the invention, are given by way of illustration only, and not by way of limitation. Various substitutions, modifications, additions, and/or arrangements, within the spirit and/or scope of the underlying inventive concepts will be apparent to those skilled in the art from this disclosure.
The present disclosure provides, in part, ultra-capacitor structures with multiple ultra-capacitor cells and methods thereof, which can be used in conjunction with electronic devices. By way of explanation, an electronic device can have numerous electronic components requiring different voltages or currents for operation. In addition, the different voltages or currents may be required for different periods of time. The ultra-capacitor structures described herein can provide multiple different voltages or currents, for different periods of times, to the electronic components. For example, different voltages or currents can be provided by different electrical interconnect configurations of the multiple ultra-capacitor cells of the ultra-capacitor structure.
As used herein, an ultra-capacitor is, for instance, an electrochemical capacitor that includes an electrolyte disposed between electrodes. An electrolyte is a substance through which electricity may pass, and may be, for example, a fluid, solid, semisolid, or flowable material. One example of an ultra-capacitor is an electrochemical double layer capacitor (EDLC), which may store electrical energy by the separation of charge, for instance, in a double layer of ions, at the interface between the surface of a conductive electrode and an electrolyte. Another term for an ultra-capacitor is a supercapacitor. An ultra-capacitor structure may include one or more ultra-capacitor cells.
Energy storage devices, including ultra-capacitor structures and batteries, may be characterized by an energy density and a power density. The energy density (also known as the specific energy) of an energy storage device is defined as the amount of energy stored per unit mass of the device, and the power density is defined as the rate per unit mass at which energy may be transferred to or from the device. Different types of energy storage devices may be compared by comparing their respective energy densities and power densities. As one example, an activated carbon ultra-capacitor may have, for example one-tenth of the energy density of a conventional lithium-ion rechargeable battery, but have, for example, 10 to 100 times the power density of the conventional lithium-ion rechargeable battery. Therefore, an ultra-capacitor may deliver a relatively large amount of energy to an electrical load over a relatively short time, as compared to a battery that may deliver a relatively small amount of energy to an electrical load over a relatively long time.
In operation, an electronic device, such as a mobile electronic device, can have multiple different operating requirements for voltage, current, power, energy, and/or RC (resistance times capacitance) time constants. For instance, certain components of the electronic device, such as a central processing unit, a memory storage device, or a display screen may steadily consume power. In addition, other components of the electronic device, such as radio transceiver, a camera flash, or a pump portion of a medical device, such as an insulin pump, may intermittently consume high power for short durations. In such a case, a battery may be used for long term storage of energy, and may be used to charge ultra-capacitor cells of an ultra-capacitor structure, which may then deliver bursts of higher levels of energy at appropriate voltage, current, power, and/or RC time constant, as needed by various electronic components.
Advantageously, the ultra-capacitor structures described herein allow, for example, a single battery at a specific nominal voltage to be used to power an electronic device, with the ultra-capacitor structures converting the power therefrom into appropriate voltages or currents as needed. This enables the elimination of inefficient and/or space consuming components, such as numerous capacitors or DC-DC converters, allowing for maximum power efficiency in a minimal footprint electronic device. For example, the ultra-capacitor structures described herein can provide several different voltages or currents to several different electrical loads, such as electronic components, either at the same time, or sequentially. Concurrently with providing several different voltages or currents to electronic components, the ultra-capacitor structures described herein can be charged using energy from at least one battery.
Generally stated, provided herein, in one aspect, is a structure. The structure includes: an ultra-capacitor structure having multiple ultra-capacitor cells; and a switching mechanism, the switching mechanism being operable to selectively connect different electrical interconnect configurations of the multiple ultra-capacitor cells of the ultra-capacitor structure to provide any one of a plurality of different voltages or currents to at least one electrical load, and to selectively control charging of the multiple ultra-capacitor cells using energy from at least one battery.
In one embodiment, the switching mechanism is operable to selectively connect an electrical interconnect configuration of first ultra-capacitor cells of the ultra-capacitor structure to provide a voltage or current to the at least one electrical load, and concurrently therewith to selectively control charging of second ultra-capacitor cells of the ultra-capacitor structure using energy from the at least one battery.
In another embodiment, the switching mechanism is operable to selectively connect a first electrical interconnect configuration of first ultra-capacitor cells of the ultra-capacitor structure to provide a first voltage or current to a first electrical load of the at least one electrical load, and concurrently therewith selectively connect a second electrical interconnect configuration of second ultra-capacitor cells of the ultra-capacitor structure to provide a second voltage or current to a second electrical load of the at least one electrical load, wherein the first voltage or current and the second voltage or current are different voltages or currents.
In a further embodiment, the switching mechanism is operable to selectively connect a first electrical interconnect configuration of first ultra-capacitor cells of the ultra-capacitor structure to provide a first voltage or current to the at least one electrical load during a first period of time, and selectively connect a second electrical interconnect configuration of second ultra-capacitor cells of the ultra-capacitor structure to provide a second voltage or current to the at least one electrical load during a second period of time, wherein the first period of time and the second period of time are sequential periods of time. In such a case, the switching mechanism is operable to selectively control charging of the second ultra-capacitor cells of the ultra-capacitor structure using energy from the at least one battery during the first period of time, and selectively control charging of the first ultra-capacitor cells of the ultra-capacitor structure using energy from the at least one battery during the second period of time.
In one implementation, a configuration of the different electrical interconnect configurations of the multiple ultra-capacitor cells of the ultra-capacitor structure comprises at least two of the multiple ultra-capacitor cells electrically connected in series configuration to the at least one electrical load. In another implementation, a configuration of the different electrical interconnect configurations of the multiple ultra-capacitor cells of the ultra-capacitor structure comprises at least two of the multiple ultra-capacitor cells electrically connected in parallel configuration to the at least one electrical load.
In a further implementation, the structure further comprises a controller, the controller being coupled to the switching mechanism and operable to control the switching mechanism to selectively electrically connect any one of the different electrical interconnect configurations of the multiple ultra-capacitor cells of the ultra-capacitor structure to the at least one electrical load, responsive in part to energy levels of the multiple ultra-capacitor cells.
In another aspect, an electronic system is presented. The electronic system includes: an ultra-capacitor structure having multiple ultra-capacitor cells; at least one battery; and a switching mechanism, the switching mechanism being operable to selectively connect different electrical interconnect configurations of the multiple ultra-capacitor cells of the ultra-capacitor structure to provide any one of a plurality of different voltages or currents to at least one electrical load, and to selectively control charging of the multiple ultra-capacitor cells using energy from the at least one battery.
Reference is made below to the drawings, which are not drawn to scale for ease of understanding, wherein the same reference numbers used throughout different figures designate the same or similar components.
In another embodiment, the connecting 120 includes: connecting a first electrical interconnect configuration of first ultra-capacitor cells of the ultra-capacitor structure to provide a first voltage or current to a first electrical load of the at least one electrical load 122; and connecting a second electrical interconnect configuration of second ultra-capacitor cells of the ultra-capacitor structure to provide a second voltage or current to a second electrical load of the at least one electrical load, wherein the first voltage or current and the second voltage or current are different voltages or currents 124.
In a further embodiment, the connecting 120 includes: connecting a first electrical interconnect configuration of first ultra-capacitor cells of the ultra-capacitor structure to provide a first voltage or current to the at least one electrical load during a first period of time 126; and connecting a second electrical interconnect configuration of second ultra-capacitor cells of the ultra-capacitor structure to provide a second voltage or current to the at least one electrical load during a second period of time, wherein the first period of time and the second period of time are sequential periods of time 128.
In particular,
In the illustrated embodiment, switches 222 are interspersed, or co-located, with ultra-capacitor cells 212. In another embodiment, the switching mechanism can be implemented in one or more centralized integrated circuits, such as, for example, an application specific integrated circuit (ASIC) or a controller, such as an embedded micro-controller. In such a case, separate or combined control lines and power lines can be provided to interconnect the multiple ultra-capacitor cells of the ultra-capacitor structure to the switching mechanism. For instance, connections 221 can include both control lines and power lines. As one specific example, the controller can be an MSP430 Micro-controller available from Texas Instruments, Inc., of Dallas, Tex.
By way of example, in the embodiment of
In a further embodiment, structure 200 includes a controller 230 coupled to switching mechanism 220. In such a case, controller 230 can be operable to control switching mechanism 220 to selectively electrically connect any one of the different electrical interconnect configurations of multiple ultra-capacitor cells 212. By way of example, controller 230 can selectively electrically connect ultra-capacitor cells 212 responsive in part to energy levels of ultra-capacitor cells 212. For instance, controller 230 can determine that one group of ultra-capacitor cells 212 is nearly depleted, and selectively control charging of that group of ultra-capacitor cells 212 using energy from at least one battery 240.
In one example, each ultra-capacitor cell includes electrodes separated by a separator and electrically connected by ions of an electrolyte located between the electrodes. For instance, the electrodes may be fabricated of a porous or spongy material, which may have a large specific surface area. Examples of electrode materials include as activated carbon, amorphous carbon, carbon aerogel, graphene, or carbon nanotubes.
In another example, electrode materials can have a specific surface area of 500-1000 square meters per gram, due to micro-porosity. In addition, the electrolyte may include a solvent with dissolved chemicals, such as potassium hydroxide (KOH). Further, the electrodes can be connected to one or more current collectors, which may include a conductive material, such as a metal, for instance, aluminum or copper. In another example, the electrode material, such as graphite, may be painted onto the current collectors. In such a case, the current collectors can act as terminals, such as positively charged anodes or negatively charged cathodes of the ultra-capacitor cells. Various materials may be used in the formation of an ultra-capacitor structure. For example, polymers, such as polyethylene terephthalate (PET), may be used to provide electrical insulation or to contain electrolytes, and adhesives may be used to bond layers together.
In the embodiment of
In one embodiment, selectively connecting can include providing any one of a plurality of different voltages or currents to at least one electrical load 250. In another embodiment, different numbers of ultra-capacitor cells can be selectively connected to the different electrical loads to provide different voltages or currents. For instance, an ultra-capacitor structure may include numerous ultra-capacitor cells, each having a voltage capacity of 2 volts (V). In such a case, switching mechanism 220 can selectively connect 3 ultra-capacitor cells in series to provide 6 V to an electrical load, or 4 ultra-capacitor cells in series to provide 8 V to an electrical load, and so forth.
In the embodiment of
By way of explanation, the techniques described herein allow for dynamic, on-the-fly configurations of ultra-capacitor cells 212 to achieve a variety of different design goals. For instance, numerous ultra-capacitor cells may be connected so that a continuous stream of energy can be delivered from a first subset of ultra-capacitor cells, and concurrently therewith, a second subset of ultra-capacitor cells can simultaneously be charged from the battery. In such an example, after the first subset of ultra-capacitor cells has been depleted, the second subset can be seamlessly switched on the fly to deliver a stream of energy, and the first subset can be charged from the battery.
In one embodiment, continuous power delivery to an electrical load can include using a smoothing circuit to deliver a constant voltage to the electrical load. For example, after the first subset of ultra-capacitor cells has been depleted, the second subset can be switched to deliver power to the electrical load before switching the first subset to be charged from the battery. In such configuration (make-before-break configuration), both the first and second subsets can be connected to the electrical load through a smoothing circuit, to ensure that a constant voltage is delivered to the electrical load. In one specific example, both subsets can be connected to the electrical load for an overlap of 0.1-10 milliseconds. In other cases, where an electronic component does not require precise input voltages, a smoothing circuit may not be used.
In another embodiment, a subset of ultra-capacitor cells can be ready to deliver an energy pulse for a short duration when needed, for example, to power the flash of a camera. In a further embodiment, a first subset of ultra-capacitor cells can be connected to an electrical load for a particular time period, and as the energy of the first subset is depleted, a second subset can be connected to the electrical load, so that a voltage delivered to the electrical load remains within a pre-determined range.
Turning to the embodiment of
In the embodiment of
In the embodiment of
In the embodiment of
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprise” (and any form of comprise, such as “comprises” and “comprising”), “have” (and any form of have, such as “has” and “having”), “include” (and any form of include, such as “includes” and “including”), and “contain” (and any form of contain, such as “contains” and “containing”) are open-ended linking verbs. As a result, a method or device that “comprises,” “has,” “includes,” or “contains” one or more steps or elements possesses those one or more steps or elements, but is not limited to possessing only those one or more steps or elements. Likewise, a step of a method or an element of a device that “comprises,” “has,” “includes,” or “contains” one or more features possesses those one or more features, but is not limited to possessing only those one or more features. Furthermore, a device or structure that is configured in a certain way is configured in at least that way, but may also be configured in ways that are not listed.
The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below, if any, are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiment was chosen and described in order to best explain the principles of one or more aspects of the invention and the practical application, and to enable others of ordinary skill in the art to understand one or more aspects of the invention for various embodiments with various modifications as are suited to the particular use contemplated.
This application claims the benefit of U.S. Provisional Patent Application No. 62/054,148, filed Sep. 23, 2014, which is hereby incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62054148 | Sep 2014 | US |
