Rechargeable battery with high compression electrode coil and method for making the same

Abstract

An electrochemical cell including an external restraint and a method of making an electrochemical cell are provided. An electrochemical cell includes a coil electrode defining a cylindrical core and extending circumferentially around the core. The coil electrode includes an anode, a cathode, and a separator and an electrolyte between the anode and the cathode. An outer restraint extends circumferentially around the coil electrode and radially compresses the coil electrode to maintain the coil electrode at a radial stack pressure. Electrochemical cells including confined electrodes and methods of making electrochemical cells are provided. The electrochemical cell also includes a wound core and a staked electrode. The staked electrode includes a core portion staked to the winding core and a coil portion spirally wound around the winding core. The constraining electrode includes a coil portion spirally wound around the winding core and a constraining portion. The constraining portion extends circumferentially around the coil portion of the electrode and radially compresses the coil portion of the electrode.

Description

[0001] This application claims the benefit of U.S. Patent Application No. 63 / 424,790, filed on Nov. 11, 2022, the entire content of which is incorporated herein by reference. Technical Field

[0002] The present disclosure generally relates to wound cell batteries or electrochemical cells, among other things. Background Art

[0003] Wound cell batteries or electrochemical cells are generally easy to manufacture and provide robust mechanical stability. Such wound cell batteries or electrochemical cells may include an anode, a cathode, and a separator in the form of a strip wound in a spiral or coil. Wound cell batteries or electrochemical cells can be used as power sources in, for example, medical devices, implantable medical devices, portable electronic devices, or electric vehicles.

[0004] In many applications, such as implantable medical devices, medical devices, and portable electronic devices, miniaturization of the cell battery is desirable. In the case of implantable medical devices, miniaturization of the cell battery can generally contribute to the miniaturization of the implantable medical device itself. Miniaturization of implantable medical devices is generally desirable because it can, for example, increase the availability of non-invasive procedures for implantation, improve patient recovery outcomes, and improve patient comfort.

[0005] Generally speaking, for a battery, it is desirable for the cell battery to have a greater energy density to meet the needs of the device, such as to last longer on a single charge or to meet greater energy demands. Increasing the energy density is also desirable for miniaturized cell batteries to meet the energy needs of devices where small form factor is important. Generally speaking, the energy density of a primary battery (i.e., a battery configured to be discharged once and then discarded or recycled) is greater than that of a secondary battery (i.e., a rechargeable battery configured to be cycled through charge and discharge cycles for reuse). In many applications, a preferred rechargeable battery is superior to a primary battery in aspects such as extending the service life of the device, meeting the average power needs of the device, and reducing waste.

[0006] A rechargeable battery may be particularly desirable in cases where a primary battery is difficult or impossible to replace, such as in implantable medical devices, where accessing the device to replace its battery (or the device itself) may require a hospitalization procedure. However, because of the lower energy density and small form factor, rechargeable batteries in implantable medical devices typically have to be recharged frequently.

[0007] In some cell batteries, such as in lithium metal rechargeable systems, the stack pressure applied to the electrode structure can improve the energy density of the battery. In other words, applying a higher mechanical load to the entire electrode structure generally increases the energy density of such cell batteries. Another benefit of stack pressure can be to stabilize or fix the electrode structure, which typically expands and contracts during charge and discharge cycles. The expansion and contraction of the electrode structure can damage components of the battery (such as current collectors) and may shorten the battery's service life. In batteries with a wound electrode structure, the expansion and contraction during charge and discharge cycles can be more significant.

[0008] In many usage scenarios and form factors, achieving high stack pressure is more difficult. This can include some wound cell batteries, batteries with a small form factor, or wound cell batteries with a small form factor. For applications in implantable medical devices, achieving stack pressure can improve energy density, thus providing miniaturization and increased capacity, as well as more charge and discharge cycles over the battery's service life.

[0009] Generally speaking, there is a need for rechargeable wound cell batteries with high stack pressure to provide increased energy density, manufacturability, robust mechanical stability, and stable battery cycling. In particular, there is a need for rechargeable wound cell batteries with high stack pressure to provide increased energy capacity, manufacturability, robust mechanical stability, and stable battery cycling, which can improve the lives, comfort, and quality of care of patients who survive or receive these implantable medical devices, such as pacemakers, insulin pumps, cardioverter defibrillators, drug delivery pumps, and nerve stimulators. Summary of the Invention

[0010] Disclosed herein are an electrochemical cell having a coiled electrode structure and a method of manufacturing the same, which can achieve a radial stack pressure similar to that achieved in a large electrochemical cell having a stacked electrode structure and an auxiliary stacking load. The electrochemical cell and method of manufacturing the same disclosed herein are suitable for a small form factor. The electrochemical cell disclosed herein and the method of manufacturing it can be used to achieve a higher energy density in rechargeable batteries and even an energy density comparable to that of primary batteries.

[0011] In one example, aspects of the present disclosure relate to an electrochemical cell that includes a coil electrode. The coil electrode may define a cylindrical core and extend circumferentially around the cylindrical core. The coil electrode may include an anode, a cathode, a separator between the anode and the cathode, and an electrolyte between the anode and the cathode. The electrochemical cell may further include an outer restraint that extends circumferentially around the coil electrode. The outer restraint may radially compress the coil electrode to hold the coil electrode under a radial stack pressure. The outer restraint may radially fix the coil electrode.

[0012] In another example, aspects of the present disclosure relate to an electrochemical cell that includes a wound core that defines a longitudinal axis. The electrochemical cell may further include a stud electrode. The stud electrode may include a core portion fixedly coupled to the wound core and a coil portion spirally wound around the wound core. The electrochemical cell may further include a restraint electrode. The restraint electrode may include a coil portion and a restraint portion. The coil portion of the restraint electrode may be spirally wound around at least a portion of the wound core and the coil portion of the stud electrode. The restraint electrode may further include a restraint portion. The restraint portion of the restraint electrode may extend circumferentially around the coil portion of the restraint electrode and the coil portion of the stud electrode and radially compress the coil portion of the restraint electrode and the coil portion of the stud electrode. The restraint portion of the restraint electrode may further radially fix the coil portion of the restraint electrode and the coil portion of the stud electrode. The electrochemical cell may further include a separator that is spirally wound around the wound core between the coil portion of the stud electrode and the coil portion of the restraint electrode. The electrochemical cell may further include an electrolyte between the coil portion of the stud electrode and the coil portion of the restraint electrode. The stud electrode and the restraint electrode may have opposite polarities.

[0013] In yet another example, aspects of the present disclosure relate to a method of manufacturing an electrochemical cell. The method includes inserting a coil electrode into a cylindrical tube. The cylindrical tube may include an inner surface. The coil electrode may define a tubular void and may include an anode, a cathode, and a separator between the anode and the cathode. The anode, the cathode, and the separator may be wound around the tubular void. The method may further include inserting the coil electrode into the cylindrical tube and inserting an expansion plug into the tubular void. Inserting the expansion plug into the tubular void may radially compress the coil electrode between the expansion plug and the inner surface of the cylindrical tube, thereby applying a radial stack pressure to the coil electrode. Inserting the expansion plug into the tubular void may further radially fix the coil electrode.

[0014] In yet another example, aspects of the present disclosure relate to a method of manufacturing an electrochemical cell. The method may include winding a coil electrode around a core. The coil electrode may include an anode, a cathode, and a separator between the anode and the cathode. The method may further include winding one of the anode or the cathode around the coil electrode, which may establish an external restraint. The external restraint may radially compress the coil electrode and apply a radial stacking pressure to the coil electrode. The external restraint may also radially fix the coil electrode.

[0015] Details of one or more aspects of the present disclosure are set forth in the following drawings and the description. Other features, objects, and advantages of the techniques described in the present disclosure will be apparent from the description, the drawings, and the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1A is a perspective view of an electrochemical cell having a closed housing in accordance with one or more embodiments of the present disclosure.

[0017] Figure 1B is Figure 1A a perspective view of the electrochemical cell of, wherein the housing is opened to show the electrode coil.

[0018] Figure 1C is Figure 1A a partially exploded perspective view of the electrochemical cell of.

[0019] Figure 1D is Figure 1A a cross-sectional side view of the electrochemical cell of.

[0020] Figure 2A is a cross-sectional side view of an electrochemical cell in accordance with one or more embodiments of the present disclosure.

[0021] Figure 2B is Figure 2A a cross-sectional front view of the electrochemical cell of.

[0022] Figure 3 is a diagram of a method of fabricating an electrochemical cell in accordance with one or more embodiments of the present disclosure.

[0023] Figures 4A to 4B is a diagram of a method of fabricating an electrochemical cell in accordance with one or more embodiments of the present disclosure.

[0024] The accompanying drawings are presented primarily for clarity and are not necessarily drawn to scale. Additionally, various structures / components may be shown diagrammatically or removed from some or all of the views to better illustrate aspects of the depicted embodiments, or where inclusion of such structures / components is not necessary for understanding the various exemplary embodiments described herein. However, the omission of illustration / description of such structures / components in a particular figure should not be construed as limiting the scope of the various embodiments in any way. Detailed Description

[0025] Unless otherwise indicated, all scientific and technical terms used herein have the meanings commonly used in the art. The definitions provided herein are intended to facilitate understanding of certain terms frequently used herein and are not intended to limit the scope of the present disclosure.

[0026] Unless otherwise indicated, the terms "polymer", "polymeric monomer", and "polymeric material" include, but are not limited to, organic homopolymers, copolymers (such as, for example, block, graft, random, and alternating copolymers, terpolymers, etc.), and blends and modifications thereof. Additionally, unless otherwise specifically defined, the term "polymer" shall include all possible geometric configurations of the material. These configurations include, but are not limited to, isotactic symmetry, syndiotactic symmetry, and atactic symmetry.

[0027] The term "substantially" modifies the term that follows it by at least about 90%, at least about 95%, or at least about 98%. "Substantially" includes "significantly", which refers to statistical significance.

[0028] The term "substantially not" modifies the term that follows it by no more than 25%, no more than 10%, no more than 5%, or no more than 2%.

[0029] In the present disclosure, it is assumed that all numbers are modified by the term "about", which encompasses the term "exactly". As used herein in connection with measured quantities, the term "about" refers to the variation in the measured quantity that a person of ordinary skill in the art would expect when making the measurement and exercising the degree of care commensurate with the purpose of the measurement and the precision of the measuring equipment used.

[0030] As used in this specification and the appended claims, unless the context clearly dictates otherwise, the singular forms "a," "an," and "the" include plural referents. It should also be noted that, unless the context clearly dictates otherwise, the term "or" is generally used in its inclusive sense of "and / or." As used herein, the terms "and / or" and "any combination thereof" and their grammatical equivalents are used interchangeably. These terms are intended to express that any combination is specifically contemplated. For illustrative purposes only, the following phrases "A, B, and / or C" or "A, B, C, or any combination thereof" can mean "A alone; B alone; C alone; A and B; B and C; A and C; and A, B, and C." The term "or" can be used conjunctively or disjunctively, unless the context clearly indicates otherwise.

[0031] Numerical ranges expressed by endpoints include all values within the range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc., or 10 or less includes 10, 9.4, 7.6, 5, 4.3, 2.9, 1.62, 0.3, etc.). Where a range of values is "up to," "at most," or "at least" a particular value, that value is included within the range.

[0032] As used herein, "have / having," "include / including," "comprise / comprising," etc. are used in their open-ended sense and generally mean "including but not limited to." It will be understood that "consisting essentially of," "consisting of," etc. are subsumed within "including," etc. As used herein, when referring to a composition, product, method, etc., "consisting essentially of" means that the components of the composition, product, method, etc. are limited to the enumerated components and any other components that do not materially affect the basic and novel characteristics of the composition, product, method, etc.

[0033] As used in this specification and the claims, the word "comprising" (and any form of "comprising", such as "comprise" or "comprises"), "having" (and any form of "having", such as "have" or "has"), "including" (and any form of "including", such as "includes" or "include"), or "containing" (and any form of "containing", such as "contains" or "contain") is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. It is contemplated that any embodiment discussed in this specification can be implemented with respect to any method or composition of the present disclosure, and vice versa. In addition, the compositions of the present disclosure can be used to implement the methods of the present disclosure. Such inclusive or open-ended words encompass more restrictive or closed terms or phrases, such as "consisting" or "consisting essentially of".

[0034] As used herein, "consisting essentially of" means that an article or method consisting essentially of the recited elements may include additional elements that do not substantially affect the basic and novel characteristics of the article or method.

[0035] The terms "preferred" and "preferably" refer to embodiments that may provide certain benefits in certain circumstances. However, in the same or other circumstances, other embodiments may also be preferred. In addition, the recitation of one or more preferred embodiments does not imply that other embodiments are not applicable and is not intended to exclude other embodiments from the scope of the present disclosure (including the claims).

[0036] References in the specification to "some embodiments", "an embodiment", "one embodiment", "embodiments", "one or more embodiments", or "other embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least some embodiments of the present disclosure, but not necessarily all embodiments.

[0037] Any directions referred to herein, such as "top", "bottom", "left", "right", "upper", "lower", and other directions and orientations are described herein for clarity with reference to the drawings and are not intended to limit the actual device or system or the use of the device or system. The device or system as described herein can be used in multiple directions and orientations.

[0038] Throughout the application, guidance is provided by way of examples, which (including their specific aspects) may be used in various combinations and are the subject of the claims. In each case, the recited lists are only used as representative groups and should not be construed as exclusive lists. It should be understood that the specific examples, materials, amounts, and procedures will be broadly interpreted in accordance with the scope and spirit of the invention set forth herein.

[0039] Reference will now be made in more detail to various embodiments of the subject matter of the present disclosure, one or more embodiments of which are illustrated in the accompanying drawings. The same numbers are used in the drawings to refer to the same components and steps. However, it should be understood that the use of numbers to refer to components in a given drawing is not intended to limit the components labeled with the same numbers in another drawing. Additionally, the use of different numbers to refer to components in different drawings is not intended to indicate that the differently numbered components cannot be the same or similar to other numbered components.

[0040] Now referring Figures 1A to 1D , an embodiment of an electrochemical cell 100 is shown. The electrochemical cell 100 includes a coil electrode 110 that defines a cylindrical core 120. A longitudinal axis A120 is defined by the cylindrical core 120. The coil electrode 110 extends circumferentially around the cylindrical core 120. The coil electrode 110 may be enclosed in a housing (e.g., housing 170). As Figure 1D shown, the coil electrode 110 includes a first electrode 130 and a second electrode 140. Each of the first electrode 130 and the second electrode 140 includes a plurality of windings around the cylindrical core 120. The first electrode 130 and the second electrode 140 are separated from each other by one or more separators (e.g., separator 150, as Figure 1D shown). The electrochemical cell 100 may be any suitable type of electrochemical cell, such as lithium metal, lithium iron phosphate or lithium iron phosphate (LFP), lithium nickel manganese cobalt oxide (NMC), lithium nickel cobalt aluminum oxide (NCA), lithium titanate, etc.

[0041] In an embodiment according to the present disclosure, the electrochemical cell 100 can have an energy density of 100 Wh / l or greater, 200 Wh / l or greater, 300 Wh / l or greater, 400 Wh / l or greater, 450 Wh / l or greater, 500 Wh / l or greater, 600 Wh / l or greater, 700 Wh / l or greater, or 800 Wh / l or greater. Any suitable method can be used to measure the energy density of the electrochemical cell 100. Suitable methods can include, for example, dividing the measured energy capacity of the electrochemical cell 100 (e.g., measured in watt-hours) by the volume of the electrochemical cell (e.g., measured in liters). Any suitable method or device can be used to measure the energy capacity of the electrochemical cell 100. Suitable methods or devices can include, for example, a battery analyzer (e.g., FLUKE BT520 battery analyzer, MACCOR Series 4000 multi-channel battery test system).

[0042] In an embodiment, the housing 170 includes a hollow body 171 that extends circumferentially around the coil electrode 110. The hollow body 171 has an inner surface 172. The housing 170 can include one or both of a head 173 and an end cap 174. The head 173 can be coupled to one end of the housing 170, and the end cap 174 can be coupled to the other end of the housing 170. The head 173 and the end cap 174 can be coupled to the housing 170, for example, by an adhesive, a welding process, or a crimp closure.

[0043] As Figure 1A shown, the head 173 can include one or more feed-through holes (e.g., feed-through hole 162). The one or more feed-through holes can be, for example, for a feed-through pin 160 or a current collector to pass through and enter the housing 170. Additionally or alternatively, the end cap 174 can include one or more feed-through holes. The housing 170 including any one of the hollow body 171, the head 173, and the end cap 174 can be made of any suitable material. Suitable housing materials can include aluminum, titanium, stainless steel, nickel, nickel-plated iron steel, or other suitable materials. In one or more embodiments, the housing 170 can include a polymeric material.

[0044] In an embodiment, the first electrode 130 includes a plurality of first electrode windings about a longitudinal axis A120. The first electrode 130 may be coupled to one or more first current collectors, such as a first feedthrough pin 160. Alternatively or additionally, the first electrode 130 may be indirectly electrically connected to the one or more first current collectors (such as the first feedthrough pin 160) via one or more conductive elements (e.g., an expansion plug 122 or a core insert 123) interposed between the first electrode and the one or more first current collectors (such as the first feedthrough pin 160). The first electrode 130 may be of any suitable thickness. Suitable first electrode thicknesses may include 0.1 mm or less, 0.15 mm or less, 0.2 mm or less, 0.25 mm or less, 0.3 mm or less, 0.35 mm or less, 0.4 mm or less, or 0.5 mm or less.

[0045] The first electrode 130 may be a strip of electrode material (i.e., a generally rectangular piece of electrode material having a width and a linear length greater than the width). The first electrode strip may be of any suitable linear length. Suitable first electrode strip linear lengths may include 30 mm or less, 40 mm or less, 50 mm or less, 60 mm or less, 70 mm or less, 80 mm or less, 90 mm or less, 100 mm or less, 120 mm or less, 140 mm or less, 160 mm or less, 180 mm or less, or 200 mm or less. Suitable first electrode strip linear lengths may also include 10 cm or more, 15 cm or more, 20 cm or more, 30 cm or more, 40 cm or more, or 50 cm or more. The first electrode strip width may be of any suitable width. Suitable first electrode strip widths may include 4 mm or less, 6 mm or less, 8 mm or less, 9 mm or less, 10 mm or less, 15 mm or less, 20 mm or less, 30 mm or less, 40 mm or less, or 50 mm or less. Suitable first electrode widths may also include 1 cm or more, 2 cm or more, 5 cm or more, 10 cm or more, or 15 cm or more.

[0046] In an embodiment, the second electrode 140 includes a plurality of second electrode windings about a longitudinal axis A120. The polarity of the second electrode 140 is opposite to the polarity of the first electrode 130. That is, in an embodiment having an anode electrode as the first electrode 130, the cathode electrode is the second electrode 140, or vice versa.

[0047] In an embodiment, the second electrode 140 is electrically insulated from the cylindrical core 120, for example, by means of a separator 150. The second electrode 140 may be electrically insulated from the first electrode 130, for example, by means of a separator 150. The second electrode 140 may be coupled to one or more second current collectors, such as a second electrode tab 175. Additionally or alternatively, the second electrode 140 may be coupled to or electrically connected to one or more second current collectors, such as a second feedthrough pin ( Figures 1A to 1D not shown in). The second electrode 140 may be of any suitable thickness. Suitable second electrode thicknesses may include 0.1 mm or less, 0.15 mm or less, 0.2 mm or less, 0.25 mm or less, 0.3 mm or less, 0.35 mm or less, 0.4 mm or less, or 0.5 mm or less.

[0048] The second electrode 140 may be a strip of electrode material. The second electrode strip may be of any suitable linear length. Suitable second electrode strip linear lengths may include 30 mm or less, 40 mm or less, 50 mm or less, 60 mm or less, 70 mm or less, 80 mm or less, 90 mm or less, 100 mm or less, 120 mm or less, 140 mm or less, 160 mm or less, 180 mm or less, or 200 mm or less. Suitable second electrode strip linear lengths may also include 10 cm or more, 15 cm or more, 20 cm or more, 30 cm or more, 40 cm or more, or 50 cm or more. The second electrode strip width may be of any suitable width. Suitable second electrode strip widths may include 4 mm or less, 6 mm or less, 8 mm or less, 9 mm or less, 10 mm or less, 15 mm or less, 20 mm or less, 30 mm or less, 40 mm or less, or 50 mm or less. Suitable second electrode widths may also include 1 cm or more, 2 cm or more, 5 cm or more, 10 cm or more, or 15 cm or more.

[0049] The second electrode tab 175 may include an extension of the electrode material of the second electrode 140. Additionally or alternatively, the second electrode tab 175 may include a separate material electrically coupled to the electrode material of the second electrode 140.

[0050] The coil electrode may include an anode electrode, which may be the first electrode 130 or the second electrode 140. The anode electrode may be made of any suitable material. Suitable anode electrode materials may include copper, lithium, graphite, lithium alloy materials, intermetallic materials (e.g., alloys), or silicon. In one or more embodiments, the anode electrode may include a copper foil. The copper foil may include a layer of metallic lithium, such as a coating or plating of lithium or a lithium alloy. The layer of metallic lithium may be any suitable thickness. Suitable metallic lithium thicknesses may include, for example, 1 micron or less, 5 microns or less, 10 microns or less, 15 microns or less, or 20 microns or less. Suitable metallic lithium thicknesses may also include, for example, 5 microns or more, 10 microns or more, 15 microns or more, 20 microns or more, 30 microns or more, or 50 microns or more.

[0051] The coil electrode may include a cathode electrode, which may be the first electrode 130 or the second electrode 140. The cathode electrode may be made of any suitable material. Suitable cathode electrode materials may include lithium-metal oxides (e.g., LiCoO2, LiMn2O4, Li(NixMnyCoz)O2, etc.), vanadium oxide, olivine (e.g., LiFePO4), rechargeable lithium oxides, silver vanadium oxide, carbon monofluoride, or manganese dioxide.

[0052] The separator 150 is disposed between or sandwiched between the first electrode 130 and the second electrode 140. The separator 150 may be in close contact with one or both of the first electrode 130 and the second electrode 140. The separator 150 may include two separate strips, each strip surrounding the cylindrical core 120 and establishing a plurality of separator windings between the first electrode 130 and the second electrode 140. Additionally or alternatively, the separator 150 may be tubular to receive one of the first electrode 130 or the second electrode 140, thereby surrounding the cylindrical core 120 and establishing a plurality of separator windings between the first electrode 130 and the second electrode 140.

[0053] The separator 150 may be porous, microporous, perforated, or may include holes for the electrolyte to penetrate into the inner layer or windings of the coil electrode 110. Thus, the separator 150 may facilitate ion transfer within the inner layer or windings of the coil electrode 110, as the electrolyte (described below) provides a medium for ion transfer, for example, between the first electrode 130 and the second electrode 140. The separator 150 may be made of any suitable material. Suitable separator materials may include polypropylene, polyethylene, polytetrafluoroethylene (PTFE), cellophane, nylon, polyolefin, microporous membranes, or multilayer microporous membranes (e.g., 2320 three - layer microporous membrane). The separator 150 can be of any suitable thickness. Suitable separator thicknesses can include 5 μm or less, 10 μm or less, 20 μm or less, 30 μm or less, 40 μm or less, or 50 μm or less.

[0054] In an embodiment, the electrochemical cell 100 includes an external restraint that extends circumferentially around the coil electrode 110. The external restraint can radially compress the coil electrode 110 to hold the coil electrode 110 under a radial stacking pressure. The external restraint can generally stabilize or radially fix the electrode coil 110, thereby preventing or inhibiting the radial expansion or contraction of the electrode coil 110. The radial stacking pressure can be any suitable pressure. Suitable radial stacking pressures include, for example, 0.1 MPa or greater, 0.3 MPa or greater, 0.5 MPa or greater, 0.7 MPa or greater, 0.9 MPa or greater, or 1 MPa or greater. Any suitable method can be used to measure the radial stacking pressure, such as by using a polymer pressure - sensitive film (e.g., FUJIFILM PRESCALE pressure - sensitive film). In the method for measuring the radial stacking pressure using a polymer pressure - sensitive film, the polymer pressure - sensitive film can be inspected immediately after the cell is formed.

[0055] In accordance with Figures 1A to 1D In an embodiment, the hollow body 171 of the housing 170 can establish the external restraint. In such embodiments, the outer surface of the coil electrode 110 (i.e., the outermost winding) can contact the inner surface 172 of the hollow body 171, thereby radially compressing the coil electrode 110.

[0056] In accordance with Figures 1A to 1D In an embodiment, the cylindrical core 120 can receive an expansion plug 122 to radially press the coil electrode 110 outward against the inner surface 172 of the hollow body 171. The external restraint can radially compress the coil electrode 110 against the expansion plug 122. The expansion plug 122 can limit the inward radial deformation of the coil electrode 110 to prevent the cylindrical core 120 from collapsing or deforming. The expansion plug 122 can maintain the coil structure of the coil electrode 110 that is radially compressed by the external restraint (i.e., the hollow body 171). The expansion plug 122 can receive or otherwise be coupled to a feed - through pin, such as the first current collector 160. The expansion plug 122 can be electrically coupled to the first current collector 160, such as by close contact or by welding (e.g., laser welding or resistance welding). The expansion plug 122 can be made of any suitable material. Suitable expansion plug materials can include aluminum, titanium, stainless steel, nickel, nickel - plated ferrous steel, or other suitable materials. The expansion plug 122 can contain a polymer material.

[0057] In one or more embodiments, the coil electrode 110 can receive a core insert 123 (asFigure 1C as shown). The core insert 123 may include windings disposed between the cylindrical core 120 and the innermost coil of the coil electrode 110. The core insert 123 may improve the accommodation of the expansion plug 122.

[0058] For example, in embodiments where the first electrode 130 and the expansion plug 122 do not easily slide against each other (i.e., the first electrode material and the expansion plug material exhibit a high frictional interaction), the core insert 123 may be made of a material that has a more desirable frictional interaction with the first electrode 130 or the expansion plug 122. In another example, in embodiments where the first electrode is fragile (e.g., in the case where the first electrode 110 is made of copper foil) and may be damaged by directly accommodating the expansion plug 122, the core insert 123 may be made of a more durable or elastic material (e.g., titanium foil) to protect the first electrode 110 from being damaged by accommodating the expansion plug 122.

[0059] The core insert 123 may be made of any suitable material. Suitable core insert materials may include, for example, titanium, titanium foil, aluminum, or aluminum foil. The core insert 123 may be made of a conductive material or an insulating material.

[0060] The electrochemical cell 100 may include one or more current collectors, each electrically connected to one of the electrodes (e.g., the feedthrough pin 160 is electrically connected to the first electrode 130 via the cylindrical core 120, as Figures 1B to 1D shown). The one or more current collectors may extend from their respective electrical connection points to outside the housing 170. The one or more current collectors may extend through one or more feedthrough holes in the housing 170. For example, as Figures 1A to 1D shown, the first feedthrough pin 160 extends through the first feedthrough hole 162 in the head 173. The first feedthrough pin 160 may be directly electrically connected to the first electrode 130. The first feedthrough pin 160 may additionally or alternatively be indirectly electrically connected to the first electrode via one or more conductive elements (e.g., the expansion plug 122 as Figure 1B shown, or the core insert 123 as Figure 1C shown) interposed between the first feedthrough pin and the first electrode 130. The one or more current collectors may be electrically insulated from the housing 170, as Figure 1D shown for the first feedthrough pin 160. The feedthrough pin 160 may be inserted through the channel 124 that extends through the expansion plug 120. The feedthrough pin 160 may be welded to the expansion plug 122 to provide a robust electrical connection between the conductive expansion plug 122 and the feedthrough pin 160.

[0061] The electrochemical cell 100 may include one or more feedthrough insulators, such as the first feedthrough insulator 161 (as Figure 1Das shown). The feedthrough insulator can be disposed in the housing 170, such as in one or both of the head 173 or the end cap 174, to electrically insulate the housing from electrical interconnects such as between the head 173 and the current collector (e.g., the first feedthrough pin 160) or between the end cap 174 and the current collector.

[0062] An embodiment of the electrochemical cell 100 includes an electrolyte disposed in the housing. Although not explicitly labeled in the figures, the electrolyte generally can fill at least a portion of any space within the housing that is not filled by other components of the electrochemical cell 100. The electrolyte can facilitate ion transfer between the first electrode 130 and the second electrode 140. The electrolyte can have an electric potential. The electrolyte can include any suitable material and can be, for example, one or more of a liquid, a gel, or a paste. The material composition of the electrolyte can depend on the cell type of the electrochemical cell. The electrolyte can include, for example, a lithium salt, sulfuric acid, sulfonyl fluoride, or other suitable electrolytes. The electrolyte can include a non-aqueous solution in which a lithium salt (e.g., lithium hexafluorophosphate) is dissolved in an organic carbonate solvent (e.g., a mixture including one or more of ethylene carbonate, dimethyl carbonate, propylene carbonate, diethyl carbonate, or ethyl methyl carbonate). The electrochemical cell 100 can include a volume (i.e., void) that is not filled with the electrolyte. The void can be retained in the electrochemical cell 100 to avoid overpressure of the outer casing.

[0063] The electrochemical cell 100 can also include various insulators (not shown in the figures) to insulate conductive components (e.g., the housing 170; the first feedthrough pin 160; the first electrode 130, the second electrode 140, etc.) from each other. The insulators can be made of any suitable material. Suitable insulator materials can include, for example, polytetrafluoroethylene (PTFE), polysulfone, glass, ceramic materials (e.g., alumina).

[0064] The electrochemical cell 100 can include various electrical connectors, such as electrical connectors between conductive components (e.g., between the first feedthrough pin 160 and the expansion plug 122, between the first feedthrough pin 160 and the first electrode 130, or between the second electrode 140 and the end cap 174). Such electrical connectors can be made by tight contact between two or more conductive materials. Additionally or alternatively, such electrical connectors can be made by welding two or more conductive materials together (e.g., by resistance welding or laser welding). In cases where the conductive materials have at least slightly incompatible metallurgical properties (such as in a connection between titanium and copper), a welding interposer (e.g., a vanadium welding interposer) can be used to manage welding stability and strength.

[0065] Now refer to Figure 2A and Figure 2B, shows an embodiment of an electrochemical cell 200 that includes a coil electrode 210 disposed within a housing 270. The coil electrode 210 includes a first electrode 230 and a second electrode 240. The coil electrode 210 defines a cylindrical core 220. A longitudinal axis A220 is defined by the cylindrical core 220. The coil electrode 210 extends circumferentially around the cylindrical core 220. The coil electrode 210 may be enclosed within a housing (e.g., the housing 270 defines a hollow tube 271 into which the coil electrode 210 may be inserted). Each of the first electrode 230 and the second electrode 240 includes a plurality of windings around the cylindrical core 220. The first electrode 230 and the second electrode 240 are separated from each other by a separator 250.

[0066] In an embodiment, the cylindrical core 220 includes a wound core 222. The coil electrode 210 may also be wound around the wound core 222. The wound core 222 may be made of any suitable material. Suitable wound core materials include, for example, aluminum, titanium, stainless steel, nickel, nickel-plated iron steel, or other suitable materials. In one or more embodiments, the wound core 222 may include a polymeric material.

[0067] In accordance with Figure 2A and Figure 2B one or more embodiments, the first electrode 230 may be a stud electrode having a core portion 231 fixedly coupled (e.g., by welding) to the wound core 222. The core portion 231 may be electrically connected to the wound core 222 (e.g., by welding). The core portion 231 may be welded to the wound core 222, for example, by resistance welding or laser welding. A welding interlayer (such as a vanadium welding interlayer) may be used to weld the core portion 231 to the wound core 222 to manage welding stability and strength.

[0068] The first electrode 230 may further include a wound portion 232 having a plurality of first electrode windings wound around the wound core 222. The wound portion 232 may be electrically connected to the core portion 231. The wound portion 232 may be made of the same material as the core portion 231. The wound portion 232 extends from the core portion 231. In one or more embodiments, the wound portion 232 and the core portion 231 include different materials. The first electrode 230 may be an anode electrode or a cathode electrode.

[0069] The first electrode 230 can be electrically connected to a current collector, such as a central feedthrough pin 260. The first electrode 230 can be directly electrically connected to the central feedthrough pin 260 (e.g., via welding). In an embodiment, the first electrode 230 is indirectly electrically connected to the central feedthrough pin, such as through the winding core 222 or other conductive elements interposed between the first electrode and the central feedthrough pin 260. The central feedthrough pin 260 can extend through the central feedthrough hole 262. The central feedthrough pin 260 can be insulated from the housing 270 by the central feedthrough insulator 261.

[0070] In one or more embodiments in accordance with Figure 2A and Figure 2B the second electrode 240 can be a constrained electrode having a constrained portion 242. The constrained portion 242 can establish an external constraint that holds the coil electrode 110 in a tightly wound configuration to maintain stack pressure and energy density, as described above. In one or more embodiments, a fixing mechanism (not shown) is applied to the constrained portion 242 to hold the external constraint. Any suitable fixing mechanism can be applied. For example, an adhesive, an adhesive tape, a weld, etc. can be used to hold the constrained portion 242 to establish the external constraint. The constrained portion 242 can include at least a portion of a winding that overlaps another portion, and the at least a portion can also be in close contact with the other portion. The constrained portion 242 can additionally or alternatively include a plurality of windings in close contact with each other. The constrained portion 242 can include a portion fixedly coupled to another portion of the constrained portion 242 or another portion of the coil electrode.

[0071] The second electrode 240 can also include a winding portion 241 having a plurality of second electrode windings wound around the winding core 222. The winding portion 241 can be electrically connected to the constrained portion 242. The winding portion 241 can be made of the same material as the constrained portion 242. Alternatively or additionally, the winding portion 241 and the constrained portion 242 can be made of different materials. The second electrode 240 can be an anode electrode or a cathode electrode. The second electrode 240 can be electrically insulated from the first electrode 230, for example, by a separator 250. The second electrode can be electrically insulated from the winding core 222, for example, by a separator 250.

[0072] The second electrode 240 can be electrically connected to a current collector, such as a radial feedthrough pin 265. The second electrode 240 can be directly electrically connected to the radial feedthrough pin 265 (e.g., via welding). The second electrode 240 can be indirectly electrically connected to the radial feedthrough pin, such as through a conductive element interposed between the second electrode and the radial feedthrough pin 265. The radial feedthrough pin 265 can extend through the radial feedthrough hole 267. The radial feedthrough pin 265 can be insulated from the housing 270 by the central feedthrough insulator 266.

[0073] In some embodiments, the electrochemical cell 200 has a "case neutral" design. In other words, the housing 270 can float at the electrolyte potential of the electrochemical cell 200. To achieve a case neutral design, the electrochemical cell can include a current collector that extends through the housing while being insulated from the housing by a feedthrough insulator. Accordingly, the head 273 of the housing 270 can include feedthrough insulators (e.g., central feedthrough insulator 261 and radial feedthrough insulator 266) for each of the current collectors (e.g., central feedthrough pin 260 and radial feedthrough pin 265), respectively).

[0074] The electrochemical cells described herein (e.g., cells 100, 200) can be manufactured in any suitable manner. In an embodiment, a coil electrode as described herein is inserted into a cylindrical housing having a hollow body with an inner surface. The coil electrode can define a tubular void (i.e., a cylindrical core). The coil electrode can include a wound core. The coil electrode can include an anode electrode wound helically around the tubular void, a cathode electrode wound helically around the tubular void, and a separator between the anode electrode and the cathode electrode, the separator also being wound helically around the tubular void or the wound coil.

[0075] Now referring Figure 3 , an embodiment of a method 300 for manufacturing an embodiment of the electrochemical cell 100' is shown. The electrochemical cell 100' is otherwise similar to Figures 1A to 1D the cell shown in. Method 300 can include step 310: inserting the coil electrode 110' into the hollow body 171' of the housing 170'. Method 300 can further include step 320: inserting the core insert 123' into the cylindrical core 120'. Method 300 can further include step 330: inserting an expansion plug 122' into the cylindrical core 120' to radially compress the coil electrode 110' between the expansion plug 122' and the inner surface 172' of the hollow body 171', thereby applying a radial stacking pressure to the coil electrode 110'. Method 300 can include step 340, which can include attaching the head 173' to the hollow body 171'. Step 340 can include: inserting the feedthrough pin 160' through the expansion plug 122'. Method 300 can further include step 350: welding the feedthrough pin 160' to the expansion plug 122'. Method 300 can further include step 360: attaching the end cap 174' to the hollow body 171'.

[0076] In some embodiments of the method of manufacturing an electrolytic cell, the method can further include: winding a coil electrode around a core. The coil electrode can include an anode electrode, a cathode electrode, and a separator between the anode electrode and the cathode electrode.

[0077] In some embodiments of a method of manufacturing an electrolytic cell, the method may include: winding one of an anode or a cathode around a coil electrode, thereby establishing an outer restraint. The outer restraint may radially fix the outer diameter of the coil electrode and compress the coil electrode after cell formation, thereby applying a radial stacking pressure to the coil electrode.

[0078] Now refer to Figure 4A and Figure 4B , which shows an embodiment of a method 400 of manufacturing an electrochemical cell 200'. The electrochemical cell 200' is otherwise similar to Figure 2A and Figure 2B the cells shown therein. Figure 4A and Figure 4B The electrochemical cell 200' depicted in Figure 4A and Figure 4B includes a central feedthrough pin 261', which is electrically connected to a second electrode 240' (i.e., the restraint electrode) via a second electrode tab 275'. Figure 4A and Figure 4B The electrochemical cell 200' depicted in Figure 4A and Figure 4B includes a radial feedthrough pin 265', which is connected to a first electrode 230' (i.e., the stud electrode) via a weld of a stud portion 231' that electrically connects the radial feedthrough pin 265' and the first electrode 230', and the weld also fixedly couples the stud portion 231' of the first electrode 230' to a winding core 222'.

[0079] Method 400 may include step 410: inserting a central feedthrough pin 260' through a central feedthrough hole 262' in a head 273', and inserting a radial feedthrough pin 265' through a radial feedthrough hole 267' in the head 273'. The head 273' may be fixed to a chuck, such as a vacuum chuck 41. Method 400 may further include step 420: adding a disc-shaped insulator to the head 273'. Method 400 may further include step 430: aligning the winding core 222' with the head 273'. Step 430 may include: inserting the central feedthrough pin 260' into a central opening 224' of the winding core 222'. Step 430 may further include: aligning the radial feedthrough pin 265' with a radial groove 223' of the winding core 222'. The winding core may be fixed to a chuck, such as a rotary chuck 42.

[0080] Method 400 may further include step 440: welding the tab portion 231' of the first electrode 230' (i.e., the tabbed electrode) to the radial feedthrough pin 265' and the wound core 222'. This weld may electrically connect the tab portion 231' of the first electrode 230' to the radial feedthrough pin 265'. This weld may also fixedly couple (i.e., tab) the tab portion 231' of the first electrode 230' to the wound core 222'. Step 440 may further include: winding the electrode coil 210' around the wound core 222', starting with the first electrode 230', followed by the second electrode 240' and the separator ( Figure 4A and Figure 4B not shown in).

[0081] Method 400 may further include step 450: completing the winding of at least one turn of the electrode coil 210' with the second electrode 240' to establish the restraint portion 242' of the second electrode 240'.

[0082] Method 400 may further include step 460, which may include: securing or fixing the coil electrode 210', for example, using a piece of tape 211' or other fastener. Step 460 may further include: adding an insulating portion, such as by inserting the core insulation 225' into the central opening 224' of the wound core 222', which may insulate the central feedthrough pin 260' from other conductive elements. Step 460 may further include: forming or attaching the second electrode tab 275', which may be electrically connected to the second electrode 240'.

[0083] Method 400 may further include step 470: electrically connecting the central feedthrough pin 260' to the second electrode tab 275', such as by welding. Step 470 may include: fixedly coupling the second electrode tab 275' to the central feedthrough pin 260', such as by welding.

[0084] Method 400 may further include step 480: inserting the coil electrode 210' into the hollow body 271'. Step 480 may further include: attaching the head 273' to the hollow body 271' to establish the housing 270'. The housing 270' may include an end cap 274', which may be formed as part of the housing 270'. The end cap 274' may also be formed as a separate part and attached to the housing 270'.

[0085] It should be understood that the various aspects disclosed herein can be combined in combinations different from those specifically presented in the specification and the drawings. It should also be understood that, depending on the example, certain actions or events of any of the processes or methods described herein can be performed in a different order, can be added, combined, or omitted entirely (e.g., not all of the described actions or events may be required to perform these techniques). Additionally, although for clarity certain aspects of the present disclosure are described as being performed by a single module or unit, it should be understood that the techniques of the present disclosure can be performed by a combination of units or modules associated with, for example, a medical device.

[0086] Exemplary embodiments

[0087] Exemplary embodiments in accordance with the present disclosure are listed below.

[0088] Embodiment 1 is an electrochemical cell that includes: (a) a coil electrode that defines a cylindrical core and extends circumferentially around the cylindrical core, the coil electrode including: (i) an anode; (ii) a cathode; (iii) a separator between the anode and the cathode; (iv) an electrolyte between the anode and the cathode; and (v) an external restraint that extends circumferentially around the coil electrode and radially compresses the coil electrode to hold the coil electrode under a radial stacking pressure.

[0089] Embodiment 2 is the battery according to Embodiment 1, wherein the coil electrode has an energy density of 300 Wh / l or greater, 400 Wh / l or greater, 500 Wh / l or greater, or 600 Wh / l or greater.

[0090] Embodiment 3 is the battery according to any of the preceding embodiments, wherein the external restraint includes an extension of the anode or the cathode.

[0091] Embodiment 4 is the battery according to any of the preceding embodiments, wherein the anode includes copper.

[0092] Embodiment 5 is the battery according to any of the preceding embodiments, wherein the anode includes a copper foil.

[0093] Embodiment 6 is the battery according to any of the preceding embodiments, wherein the external restraint includes a cylindrical tube.

[0094] Embodiment 7 is the battery according to Embodiment 6, the battery further including an expansion plug within the cylindrical coil, wherein the expansion plug presses the coil electrode against the cylindrical tube.

[0095] Embodiment 8 is the battery according to any one of the foregoing embodiments, the battery further comprising an expansion plug, the expansion plug being within the cylindrical coil, wherein the expansion plug radially presses the coil electrode against the outer restraint.

[0096] Embodiment 9 is the battery according to any one of the foregoing embodiments, the battery further comprising a feedthrough pin, the feedthrough pin being electrically connected to one of the anode or the cathode.

[0097] Embodiment 10 is the battery according to any one of the foregoing embodiments, wherein the stack pressure is at least 0.3 MPa, at least 0.4 MPa, at least 0.5 MPa, at least 0.6 MPa, at least 0.7 MPa, at least 0.8 MPa, at least 0.9 MPa or at least 1 MPa.

[0098] Embodiment 11 is the battery according to any one of the foregoing embodiments, the battery further comprising a winding core, the winding core being within the cylindrical core.

[0099] Embodiment 12 is the battery according to Embodiment 11, wherein the winding core is fixedly connected to the anode or the cathode.

[0100] Embodiment 13 is the battery according to any one of the foregoing embodiments, wherein the outer restraint radially fixes the coil electrode.

[0101] Embodiment 14 is an electrochemical cell, the electrochemical cell comprising: (a) a winding core defining a longitudinal axis; (b) a stud electrode comprising: a core portion fixedly connected to the winding core; and a coil portion helically wound around the winding core; (c) a restraint electrode comprising: a coil portion helically wound around at least a portion of the winding core and the coil portion of the stud electrode; and a restraint portion circumferentially extending around the coil portion of the restraint electrode and the coil portion of the stud electrode and radially compressing the coil portion of the restraint electrode and the coil portion of the stud electrode; (d) a separator helically wound around the winding core between the coil portion of the stud electrode and the coil portion of the restraint electrode; and (e) an electrolyte between the coil portion of the stud electrode and the coil portion of the restraint electrode; wherein the stud electrode and the restraint electrode have opposite polarities.

[0102] Embodiment 15 is the battery according to Embodiment 14, wherein the stud electrode is the anode.

[0103] Embodiment 16 is the battery according to any one of Embodiments 14 or 15, wherein the stud electrode comprises copper.

[0104] Embodiment 17 is the battery according to Embodiment 14, wherein the restraining electrode is the anode.

[0105] Embodiment 18 is the battery according to any one of Embodiments 14 or 17, wherein the restraining electrode comprises copper.

[0106] Embodiment 19 is the battery according to any one of Embodiments 14 to 18, wherein the core portion of the stud electrode is formed of a first material, and wherein the coil portion of the stud electrode is formed of a second material different from the first material.

[0107] Embodiment 20 is the battery according to any one of Embodiments 14 to 19, wherein the core portion of the stud electrode is electrically connected to the coil portion of the stud electrode.

[0108] Embodiment 21 is the battery according to any one of Embodiments 14 to 20, wherein the restraining portion of the restraining electrode radially fixes the coil portion of the restraining electrode and the coil portion of the stud electrode.

[0109] Embodiment 22 is the battery according to any one of Embodiments 14 to 21, wherein the battery has an energy density of 300 Wh / l or greater, 400 Wh / l or greater, 500 Wh / l or greater, or 600 Wh / l or greater.

[0110] Embodiment 23 is a method of manufacturing an electrochemical cell, the method comprising: (a) inserting a coil electrode into a cylindrical tube including an inner surface, the coil electrode defining a tubular void and comprising an anode, a cathode, and a separator between the anode and the cathode, wherein the anode, the cathode, and the separator are wound around the tubular void; (b) inserting the coil electrode into the cylindrical tube; (c) inserting an expansion plug into the tubular void to radially compress the coil electrode between the expansion plug and the inner surface of the cylindrical tube, thereby applying a radial stacking pressure to the coil electrode.

[0111] Embodiment 24 is a method of manufacturing an electrochemical cell, the method comprising: (a) winding a coil electrode around a core, the coil electrode comprising an anode, a cathode, and a separator between the anode and the cathode; (b) winding one of the anode or the cathode around the coil electrode, establishing an external restraint that radially compresses the coil electrode and applies a radial stacking pressure to the coil electrode.

[0112] Embodiment 25 is the method according to any one of Embodiments 23 or 24, wherein the radial stacking pressure is at least 0.3 MPa, at least 0.4 MPa, at least 0.5 MPa, at least 0.6 MPa, at least 0.7 MPa, at least 0.8 MPa, at least 0.9 MPa, or at least 1 MPa.

[0113] Embodiment 26 is the method according to any one of Embodiments 23 to 25, wherein the electrochemical cell has an energy density of 300 Wh / l or greater, 400 Wh / l or greater, 500 Wh / l or greater, or 600 Wh / l or greater.

[0114] Embodiment 27 is the method according to any one of Embodiments 23 to 26, the method further comprising electrically connecting an anode current collector to the anode.

[0115] Embodiment 28 is the method according to any one of Embodiments 23 to 27, the method further comprising electrically connecting a cathode current collector to the cathode.

[0116] Embodiment 29 is the method according to any one of Embodiments 23 to 28, wherein the anode comprises copper.

[0117] Embodiment 30 is the method according to any one of Embodiments 23 to 29, wherein the anode comprises a copper foil.

Claims

1. An electrochemical cell, the electrochemical cell comprising: A coil electrode, the coil electrode defining a cylindrical core and extending circumferentially around the cylindrical core, the coil electrode comprising: An anode; A cathode; A separator located between the anode and the cathode; An electrolyte located between the anode and the cathode; and An external restraint extending circumferentially around the coil electrode and radially compressing the coil electrode to hold the coil electrode under a radial stacking pressure.

2. The cell according to claim 1, wherein the coil electrode has an energy density of 300 Wh / l or greater, 400 Wh / l or greater, or 500 Wh / l or greater.

3. The cell according to claim 1 or 2, wherein the external restraint comprises an extension of the anode or the cathode.

4. The method according to any one of claims 1 to 5, wherein the external restraint comprises a cylindrical tube.

5. The cell according to claim 4, the cell further comprising an expansion plug located in the cylindrical coil, wherein the expansion plug presses the coil electrode against the cylindrical tube.

6. The cell according to any one of claims 1 to 5, wherein the stacking pressure is at least 0.5 MPa.

7. The cell according to any one of claims 1 to 6, the cell further comprising a wound core located in the cylindrical core.

8. The cell according to claim 7, wherein the wound core is fixedly coupled to the anode or the cathode.

9. An electrochemical cell, the electrochemical cell comprising: A wound core defining a longitudinal axis; A stud electrode, the stud electrode comprising: A core portion fixedly coupled to the wound core; and A coil portion helically wound around the wound core; A restraint electrode, the restraint electrode comprising: A coil portion helically wound around at least a portion of the wound core and the coil portion of the stud electrode; and A restraint portion extending circumferentially around the coil portion of the restraint electrode and the coil portion of the stud electrode and radially compressing the coil portion of the restraint electrode and the coil portion of the stud electrode; A separator helically wound around the wound core between the coil portion of the stud electrode and the coil portion of the restraint electrode; and An electrolyte located between the coil portion of the stud electrode and the coil portion of the restraint electrode; Wherein the stud electrode and the restraint electrode have opposite polarities.

10. The cell according to claim 9, wherein the stud electrode is an anode.

11. The cell according to claim 9 or 10, wherein the restraint electrode is an anode.

12. The cell according to any one of claims 9 to 10, wherein the core portion of the stud electrode is formed of a first material, and wherein the coil portion of the stud electrode is formed of a second material different from the first material.

13. The battery according to any one of claims 9 to 12, wherein the constraining portion of the constraining electrode radially fixes the coil portion of the constraining electrode and the coil portion of the stud electrode.

14. A method of manufacturing an electrochemical cell, the method comprising: inserting a coil electrode into a cylindrical tube including an inner surface, the coil electrode defining a tubular void and including an anode, a cathode, and a separator located between the anode and the cathode, wherein the anode, the cathode, and the separator are wound around the tubular void; inserting the coil electrode into the cylindrical tube; inserting an expansion plug into the tubular void to radially compress the coil electrode between the expansion plug and the inner surface of the cylindrical tube, thereby applying a radial stacking pressure to the coil electrode.

15. A method of manufacturing an electrochemical cell, the method comprising: winding a coil electrode around a core, the coil electrode including an anode, a cathode, and a separator located between the anode and the cathode; winding one of the anode or the cathode around the coil electrode, establishing an external constraint that radially compresses the coil electrode and applies a radial stacking pressure to the coil electrode.

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