Patent Application
20160141577
Oil wells are created by drilling a hole into the earth, in some cases using a drilling rig that rotates a drill string (e.g., drill pipe) having a drill bit attached thereto. In other cases, the drilling rig does not rotate the drill bit. For example, the drill bit can be rotated downhole. The drill bit, aided by the weight of pipes (e.g., drill collars) cuts into rock within the earth. Drilling fluid (e.g., mud) is pumped into the drill pipe and exits at the drill bit. The drilling fluid may be used to cool the bit, lift rock cuttings to the surface, at least partially prevent destabilization of the rock in the wellbore, and/or at least partially overcome the pressure of fluids inside the rock so that the fluids do not enter the wellbore. Other equipment can also be used for evaluating formations, fluids, production, other operations, and so forth. Downhole equipment can be powered by remote energy sources that power the equipment via transmission lines (e.g., electrical, optical, mechanical, or hydraulic transmission lines). Downhole equipment can also be powered by local energy sources such as local generators or energy storage devices (e.g., battery packs) coupled with the equipment.
Aspects of the disclosure can relate to an energy storage device including at least two electrodes (e.g., an anode and a cathode). At least one of the two electrodes can be formed from lithium or a lithium alloy. The energy storage device can also include an electrolyte solution in contact with the two electrodes and a separator with a melting point higher than a melting point of lithium. The separator can define a boundary between the two electrodes and encapsulates at least one of the two electrodes. The separator can also be impermeable to molten lithium. Thus, when exposed to a temperature that causes lithium from one or more of the electrodes to melt, the separator can prevent contact between molten lithium from one electrode and the other electrode.
Other aspects of the disclosure can relate to a method for providing an energy storage device with at least one encapsulated electrode. The method includes provisioning two electrodes. At least one of the two electrodes can include lithium or a lithium alloy. At least one of the two electrodes can be encapsulated with a separator having a melting point higher than a melting point of lithium and being impermeable to molten lithium. Thus, the separator can define a boundary between the two electrodes. The method can also include provisioning two electrical leads. Each of the two electrical leads can be placed in contact with a respective one of the two electrodes. At least one of the two electrical leads can extend from an encapsulated one of the two electrodes through the separator via a tightly fitting through hole of the separator such that molten lithium cannot leak into or out of the separator from around the electrical lead. An electrolyte solution can be provided in contact with the two electrodes. The two electrodes and the electrolyte solution can also be contained in a vessel including ports for connecting the two electrical leads with respective electrical leads of an external device.
Also, aspects of the disclosure can relate to a system including downhole equipment and an energy storage device coupled with the downhole equipment to power the downhole equipment. The energy storage device can include two electrodes and an electrolyte solution in contact with the two electrodes. At least one of the two electrodes can include lithium or a lithium alloy. The energy storage device can also include a separator with a melting point higher than a melting point of lithium. The separator can be impermeable to molten lithium and can encapsulate at least one of the two electrodes such that it defines a boundary between the two electrodes. The energy storage device can also include two electrical leads. Each of the two electrical leads can be set in contact with a respective one of the two electrodes. At least one of the two electrical leads can be extended from an encapsulated one of the two electrodes through the separator via a tightly fitting through hole of the separator such that molten lithium cannot leak into or out of the separator from around the electrical lead. The energy storage device can also include a vessel containing the two electrodes and the electrolyte solution. The vessel can include ports for connecting the two electrical leads with respective electrical leads of the downhole equipment.
This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.
Embodiments of an energy storage device with an encapsulated electrode are described with reference to the following figures. The same numbers are used throughout the figures to reference like features and components.
A bottom hole assembly (BHA) 116 is suspended at the end of the drill string 104. The bottom hole assembly 116 includes a drill bit 118 at its lower end. In embodiments of the disclosure, the drill string 104 includes a number of drill pipes 120 that extend the bottom hole assembly 116 and the drill bit 118 into subterranean formations. Drilling fluid (e.g., mud) 122 is stored in a tank and/or a pit 124 formed at the wellsite. The drilling fluid can be water-based, oil-based, and so on. A pump 126 displaces the drilling fluid 122 to an interior passage of the drill string 104 via, for example, a port in the rotary swivel 114, causing the drilling fluid 122 to flow downwardly through the drill string 104 as indicated by directional arrow 128. The drilling fluid 122 exits the drill string 104 via ports (e.g., courses, nozzles) in the drill bit 118, and then circulates upwardly through the annulus region between the outside of the drill string 104 and the wall of the borehole 102, as indicated by directional arrows 130. In this manner, the drilling fluid 122 cools and lubricates the drill bit 118 and carries drill cuttings generated by the drill bit 118 up to the surface (e.g., as the drilling fluid 122 is returned to the pit 124 for recirculation).
In some embodiments, the bottom hole assembly 116 includes a logging-while-drilling (LWD) module 132, a measuring-while-drilling (MWD) module 134, a rotary steerable system 136, a motor, and so forth (e.g., in addition to the drill bit 118). The logging-while-drilling module 132 can be housed in a drill collar and can contain one or a number of logging tools. It should also be noted that more than one LWD module and/or MWD module can be employed (e.g. as represented by another logging-while-drilling module 138). In embodiments of the disclosure, the logging-while drilling modules 132 and/or 138 include capabilities for measuring, processing, and storing information, as well as for communicating with surface equipment, and so forth.
The measuring-while-drilling module 134 can also be housed in a drill collar, and can contain one or more devices for measuring characteristics of the drill string 104 and drill bit 118. The measuring-while-drilling module 134 can also include components for generating electrical power for the down hole equipment. This can include a mud turbine generator (also referred to as a “mud motor”) powered by the flow of the drilling fluid 122. However, this configuration is provided by way of example and is not meant to limit the present disclosure. In other embodiments, other power and/or battery systems can be employed. The measuring-while-drilling module 134 can include one or more of the following measuring devices: a weight-on-bit measuring device, a torque measuring device, a vibration measuring device, a shock measuring device, a stick slip measuring device, a direction measuring device, an inclination measuring device, and so on.
In embodiments of the disclosure, the wellsite system 100 is used with controlled steering or directional drilling. For example, the rotary steerable system 136 is used for directional drilling. As used herein, the term “directional drilling” describes intentional deviation of the wellbore from the path it would naturally take. Thus, directional drilling refers to steering the drill string 104 so that it travels in a desired direction. In some embodiments, directional drilling is used for offshore drilling (e.g., where multiple wells are drilled from a single platform). In other embodiments, directional drilling enables horizontal drilling through a reservoir, which enables a longer length of the wellbore to traverse the reservoir, increasing the production rate from the well. Further, directional drilling may be used in vertical drilling operations. For example, the drill bit 118 may veer off of a planned drilling trajectory because of the unpredictable nature of the formations being penetrated or the varying forces that the drill bit 118 experiences. When such deviation occurs, the wellsite system 100 may be used to guide the drill bit 118 back on course.
Drill assemblies can be used with, for example, a wellsite system (e.g., the wellsite system 100 described with reference to
A drill assembly includes a body for receiving a flow of drilling fluid. The body comprises one or more crushing and/or cutting implements, such as conical cutters and/or bit cones having spiked teeth (e.g., in the manner of a roller-cone bit). In this configuration, as the drill string is rotated, the bit cones roll along the bottom of the borehole in a circular motion. As they roll, new teeth come in contact with the bottom of the borehole, crushing the rock immediately below and around the bit tooth. As the cone continues to roll, the tooth then lifts off the bottom of the hole and a high-velocity drilling fluid jet strikes the crushed rock chips to remove them from the bottom of the borehole and up the annulus. As this occurs, another tooth makes contact with the bottom of the borehole and creates new rock chips. In this manner, the process of chipping the rock and removing the small rock chips with the fluid jets is continuous. The teeth intermesh on the cones, which helps clean the cones and enables larger teeth to be used. A drill assembly comprising a conical cutter can be implemented as a steel milled-tooth bit, a carbide insert bit, and so forth. However, roller-cone bits are provided by way of example and are not meant to limit the present disclosure. In other embodiments, a drill assembly is arranged differently. For example, the body of the bit comprises one or more polycrystalline diamond compact (PDC) cutters that shear rock with a continuous scraping motion.
In embodiments of the disclosure, the body of a drill assembly can define one or more nozzles that allow the drilling fluid to exit the body (e.g., proximate to the crushing and/or cutting implements). The nozzles allow drilling fluid pumped through, for example, a drill string to exit the body. For example, drilling fluid can be furnished to an interior passage of the drill string by the pump and flow downwardly through the drill string to a drill bit of the bottom hole assembly, which can be implemented using, for example, a drill assembly. Drilling fluid then exits the drill string via nozzles in the drill bit, and circulates upwardly through the annulus region between the outside of the drill string and the wall of the borehole. In this manner, rock cuttings can be lifted to the surface, destabilization of rock in the wellbore can be at least partially prevented, the pressure of fluids inside the rock can be at least partially overcome so that the fluids do not enter the wellbore, and so forth.
Modern oil and gas exploration increasingly uses electronic devices in the borehole to provide measurements, and for control and operational optimization. Although a wellsite drilling system 100 is described herein, those skilled in the art will appreciated that any wellsite system can include downhole electronic equipment (e.g., sensors, actuators, communication devices, or the like). When operating electronics as part of a drill string and/or other downhole equipment and/or strings (e.g., for well testing, well simulation, well monitoring, formation evaluation, etc.), available power in the borehole may be limited near a bottom hole assembly. In some cases, electrical power can be generated by turbines while fluids are pumped into and/or out of a well, but this technique may not be efficient when there is little or no movement of fluids. Batteries can also be installed in electronic equipment to provide electrical power in a borehole, but batteries have a finite energy storage capacity, which limits the amount of time the equipment can be operated. In some cases, larger batteries may be used, but the amount of space available in the borehole is also finite, limiting the size of such batteries. In other cases, higher power density batteries may be used, but such batteries may be more prone to failure (e.g., in the high temperature operating conditions present downhole). The availability of energy to various sensors, actuators, communication modules (e.g., receivers or transmitters) and other downhole equipment in oil wells is a difficult issue due to the harsh environment in terms of temperature and vibration. High temperatures (e.g., 200° C. and above) can be encountered down hole, but equipment may also operate at room temperature. Sometimes a wide range of temperatures is encountered in operation.
As described herein, batteries can use lithium (Li) or lithium alloy in at least one of the electrodes (i.e., in the anode, the cathode, or both). Yet, it has been found that the maximum operating temperature of a battery cell can be limited by the melting point of lithium (˜180° C.). Alloys, such as lithium magnesium alloys, can be used in an electrode to increase the effective melting point of the electrode (e.g., the temperature at which at least a portion of the electrode begins to melt). However, it has been found that at high temperatures molten lithium can seep through the alloy formation and enter in contact with the other electrode, thus providing a short circuit that can cause the battery to fail. Additionally, it has been found that use of other metals with lithium to form alloys exhibiting higher melting points can result an increase in overall battery size to achieve adequate storage capacity.
As shown in
At least one of the two electrodes 202 includes lithium or a lithium alloy. In some embodiments, at least one of the two electrodes can be formed from lithium or an alloy with at least 60% lithium content. For example, the alloy can include about 60% to about 100% lithium content. By way of further example, the alloy can include about 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% lithium content. In this regard, higher lithium content can result in higher storage capacity and/or reduced overall size of the energy storage device 200.
The energy storage device 200 also includes a separator 208 with a melting point higher than a melting point of lithium. The separator 208 is also impermeable to molten lithium. For example, the separator 208 can be formed from a polymer, a polyimide, fiberglass, a ceramic material, or the like. Although the separator 208 is impermeable to molten lithium, the separator 208 is permeable to electrolytes from the electrolyte solution 206 to allow electrolyte flow between the electrodes 202. The separator 208 encapsulates at least one of the two electrodes 202 and defines a boundary between the two electrodes 206. At high temperatures (e.g., above a melting point of lithium), the separator 208 contains molten lithium from an encapsulated one of the two electrodes 202 and/or protects the encapsulated one of the two electrodes 202 from molten lithium of another one of the two electrodes 202. Thus, the separator 208 prevents the electrodes 202 from short circuiting with one another.
The energy storage device 200 can also include two electrical leads 210. Each of the two electrical leads 210 is in contact with a respective one of the two electrodes 202. At least one of the two electrical leads 210 extends from an encapsulated one of the two electrodes 202 through the separator 208 via a tightly fitting through hole 212 (e.g., “tightly fitting” such that molten lithium cannot leak into or out of the separator 208 from around the electrical lead 210). The through hole 212 may be lined with a gasket and/or tightly formed around the electrical lead 210 to avoid seepage of molten lithium into or out of the encapsulated one of the two electrodes 202. The vessel 204 can include ports (e.g., through holes or interfacing connectors/leads) for connecting the two electrical leads 210 with respective electrical leads of the downhole equipment 140 or any other device powered by the energy storage device 200.
As shown in
The separator 208 can be formed from a flexible separator material (e.g., a polymer or polyimide). As shown in
As discussed above, an electrical lead 210 can be placed in contact with the encapsulated electrode 202 via a tightly fitting through hole 212 formed in the separator 208. In some embodiments, the electrical lead 210 is coupled to the electrode 202 prior to encapsulation with the separator 208 (i.e., before the edges are sealed off) so that the separator material is tightly fit around the electrical lead 210 during a sealing process to form the tightly fitting through hole 212. In other embodiments, the through hole 212 is formed in the separator 208 after the electrode 202 is encapsulated. The through hole 212 can be lined with a gasket or resin that tightly fits the through hole 212 around the electrical lead 210 so that molten lithium cannot seep out of the separator 208 from any openings around the electrical lead 210.
As shown in
Where a bobbin or jellyroll configuration is implemented, the separator 208 may form an outer layer that wraps around both of the electrodes 202 (e.g., as shown in
Bobbin or jellyroll configurations can be used to prepare the electrodes 202 for insertion in the vessel 204, which can include a cylindrical canister. However, the vessel 204 and the electrode configuration are not limited to cylindrical formation. Those skilled in the art will appreciate that the electrodes 202 can be arranged in rectangular and other geometric formations as well. Some of these formations may include aspects of the bobbin or jellyroll configurations described above. Some formations may simply include a first electrode 202 placed in parallel with a second electrode 202. Various arrangements can be implemented without departing from the scope of the energy storage device 200 described herein.
A system implementing a drill assembly or any other downhole equipment 140, including one or more of its components, can operate under computer control and can be powered by a local storage device (e.g., a battery or battery pack), such as the energy storage device 200. For example, a processor can be included with or in a system to control the components and functions of systems described herein using software, firmware, hardware (e.g., fixed logic circuitry), manual processing, or a combination thereof. The terms “controller,” “functionality,” “service,” and “logic” as used herein generally represent software, firmware, hardware, or a combination of software, firmware, or hardware in conjunction with controlling the systems. In the case of a software implementation, the module, functionality, or logic represents program code that performs specified tasks when executed on a processor (e.g., central processing unit (CPU) or CPUs). The program code can be stored in one or more computer-readable memory devices (e.g., internal memory and/or one or more tangible media), and so on. The structures, functions, approaches, and techniques described herein can be implemented on a variety of commercial computing platforms having a variety of processors.
The drill assembly can be coupled with a controller including a processor, a memory, and a communications interface. The processor provides processing functionality for the controller and can include any number of processors, micro-controllers, or other processing systems, and resident or external memory for storing data and other information accessed or generated by the controller. The processor can execute one or more software programs that implement techniques described herein. The processor is not limited by the materials from which it is formed or the processing mechanisms employed therein and, as such, can be implemented via semiconductor(s) and/or transistors (e.g., using electronic integrated circuit (IC) components), and so forth.
The memory is an example of tangible, computer-readable storage medium that provides storage functionality to store various data associated with operation of the controller, such as software programs and/or code segments, or other data to instruct the processor, and possibly other components of the controller, to perform the functionality described herein. Thus, the memory can store data, such as a program of instructions for operating the system (including its components), and so forth. It should be noted that while a single memory is described, a wide variety of types and combinations of memory (e.g., tangible, non-transitory memory) can be employed. The memory can be integral with the processor, can comprise stand-alone memory, or can be a combination of both. The memory can include, but is not necessarily limited to: removable and non-removable memory components, such as random-access memory (RAM), read-only memory (ROM), flash memory (e.g., a secure digital (SD) memory card, a mini-SD memory card, and/or a micro-SD memory card), magnetic memory, optical memory, universal serial bus (USB) memory devices, hard disk memory, external memory, and so forth.
The communications interface is operatively configured to communicate with components of the system. For example, the communications interface can be configured to transmit data for storage in the system, retrieve data from storage in the system, and so forth. The communications interface is also communicatively coupled with the processor to facilitate data transfer between components of the system and the processor (e.g., for communicating inputs to the processor received from a device communicatively coupled with the controller). It should be noted that while the communications interface is described as a component of a controller, one or more components of the communications interface can be implemented as external components communicatively coupled to the system via a wired and/or wireless connection. The system can also comprise and/or connect to one or more input/output (I/O) devices (e.g., via the communications interface), including, but not necessarily limited to: a display, a mouse, a touchpad, a keyboard, and so on.
The communications interface and/or the processor can be configured to communicate with a variety of different networks, including, but not necessarily limited to: a wide-area cellular telephone network, such as a 3G cellular network, a 4G cellular network, or a global system for mobile communications (GSM) network; a wireless computer communications network, such as a WiFi network (e.g., a wireless local area network (WLAN) operated using IEEE 802.11 network standards); an internet; the Internet; a wide area network (WAN); a local area network (LAN); a personal area network (PAN) (e.g., a wireless personal area network (WPAN) operated using IEEE 802.15 network standards); a public telephone network; an extranet; an intranet; and so on. However, this list is provided by way of example and is not meant to limit the present disclosure. Further, the communications interface can be configured to communicate with a single network or multiple networks across different access points.
Referring now to
Although a few example embodiments have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the example embodiments without materially departing from an energy storage device with an encapsulated electrode. Features shown in individual embodiments referred to above may be used together in combinations other than those which have been shown and described specifically. Accordingly, any such modification is intended to be included within the scope of this disclosure as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not just structural equivalents, but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures. It is the express intention of the applicant not to invoke 35 U.S.C. §112, paragraph 6 for any limitations of any of the claims herein, except for those in which the claim expressly uses the words ‘means for’ together with an associated function.
