Shape-matching battery pack assembly

Abstract

The conformal battery pack assembly includes an array of electrically connected individual electrochemical cells surrounded and encapsulated by a flexible outer shell, and the array is geometrically arranged such that there are at least three non-parallel bending axes.

Description

Technical Field

[0001] The present disclosure relates to portable or wearable battery packs, and more particularly to a shape-conforming battery pack assembly.

Background Art

[0002] Portable consumer electronic devices have specific power requirements. Generally, small wearable consumer electronic devices receive power from a single battery (contained within the device itself) or from a portable battery pack that may include one or more battery cells. These portable battery packs are typically housed within a hard plastic outer shell that can be attached to the user by a strap or carried by the user within a pocket or other carrying location. These hard battery packs are uncomfortable when strapped to the body or placed in a pocket. Additionally, such battery packs bulge the clothing when worn under the clothes. This is aesthetically undesirable and can also be uncomfortable. Further, current battery packs require inconvenient connection cords to supply power to the device.

[0003] U.S. Patent No. 9,343,716 describes a battery assembly including a plurality of cells. These cells have an upper laminate layer and a lower laminate layer bonded together by an adhesive, which allows for the possibility of removing one or more cells for flexibility and better fit within a device. These battery assemblies are configured such that the upper laminate layer and the lower laminate layer are connected to the cells and to each other by an adhesive.

Summary of the Invention

[0004] According to the first embodiment, the shape-conforming battery pack assembly includes an array of individual electrochemical cells electrically connected to one another. The array is enclosed and encapsulated by a flexible outer shell. The array is geometrically arranged such that at least three non-parallel bending axes exist.

[0005] According to a second embodiment, the shape-conforming battery pack assembly includes an array of individual electrochemical cells electrically connected to one another. The array is enclosed and encapsulated by a flexible outer shell. The electrical connections between the cells are configured to reduce material stress, thereby allowing extension and / or bending and / or torsion over a planned number of flexing cycles without exceeding the fatigue limit stress on the electrical connections.

[0006] According to a third embodiment, the shape-conforming battery pack assembly includes an array of individual electrochemical cells electrically connected to one another. The array is enclosed and encapsulated by a flexible shell. Electronic components are operably connected to the array of individual electrochemical cells. The electronic components are enclosed and encapsulated by a flexible shell. The array is geometrically arranged such that at least three non-parallel bending axes exist.

[0007] The above embodiments of the shape-fitting battery pack assembly may further include one or more of the following optional features, structures, and / or forms:

[0008] In some optional forms, the array has a shape that is approximately circular or polygonal, such as an octagon or a hexagon.

[0009] In other optional configurations, the array includes an opening. In some optional configurations, electronic components are located within the opening and are electrically connected in series or parallel to the cell array. In some optional configurations, the opening is 4 mm or less.

[0010] In some optional forms, the electronic component is a sensor, and for example, the electronic component may be a physiological sensor.

[0011] In other optional forms, the maximum size of the outer shell is 22mm x 35mm.

[0012] In other optional configurations, the battery array is configured to produce more than 20mAh at a nominal 3.0V.

[0013] In other optional forms, the outer shell includes slits or perforations to facilitate bending.

[0014] In other optional forms, the electrical connections between cells include highly conductive flexible materials. In some optional forms, the electrical connections include copper, nickel, stainless steel, brass, metal alloys, carbon fiber, conductive polymers, or combinations thereof.

[0015] In other optional forms, the shape of the electrical connection may be a loop, coil, helix or spiral, offset, or convex shape to improve flexibility. In other optional forms, the electrical connection may be configured to have a circular, elliptical, rectangular, or other cross-sectional shape.

[0016] In other optional configurations, the electrical connection connects the top, bottom, or sides of the cells. In other optional configurations, the electrical connection connects the top of one cell to the bottom of another cell.

[0017] In other optional forms, electrical connections are made by thermal welding, resistance welding, laser welding, or ultrasonic welding.

[0018] In other optional forms, the electrical connections are soldered, brazed, bonded with conductive adhesive, or held together by mechanical pressure.

[0019] In other alternative forms, the flexible outer shell includes an outer shell material having a fracture elongation ratio of 1.1 to 1.8, a maximum tensile strength of 1.0 MPa to 50 MPa, and / or a Young's modulus of 0.5 kPa to 140 kPa.

[0020] In other alternative forms, the flexible outer shell material includes an elastomer.

[0021] In other alternative forms, an adhesive is disposed on one or both sides of the flexible outer shell.

[0022] In other alternative forms, the flexible outer shell material has a hardness of HOOO-S 10 to 90A, preferably HOO-5 to 30A, more preferably OO-10 to OO-50, as defined by ASTM standard D2240-15.

[0023] In other alternative forms, the outer shell material has an elongation at break of 10% to 1,000%.

[0024] In other alternative forms, the electronic component includes one or more of a processor, a microprocessor, a signal processor, an integrated circuit, a display, a capacitor, a resistor, a transistor, a medical device such as a glucose delivery device or an automated external defibrillator, a global positioning system (GPS) receiver, a sensor (such as a biometric sensor, a temperature sensor, an accelerometer, a moisture sensor, etc.), or an antenna.

[0025] In other alternative forms, the electronic component is operably connected to the surface of one electrochemical cell within an array of individual electrochemical cells.

[0026] In other alternative forms, the electronic component is positioned within the flexible outer shell.

[0027] In other alternative forms, the electronic component is surrounded and encapsulated by the flexible outer shell.

Brief Description of the Drawings

[0028] This specification concludes with claims that particularly point out and distinctly claim the subject matter regarded as forming the present disclosure, but the invention will be better understood from the following description when taken in conjunction with the accompanying drawings.

[0029] [Figure 1] It is a top perspective view of a shape-conforming battery pack assembly constructed in accordance with the present disclosure. [Figure 2] It is a bottom perspective view of the battery pack assembly of FIG. 1. [Figure 3] It is a side view of the battery pack assembly of FIG. 1. [Figure 4A] It is a top view of various additional embodiments of a battery pack assembly having a plurality of electrochemical cells of a first size. [Figure 4B] It is a top view of various additional embodiments of a battery pack assembly having a plurality of electrochemical cells of a first size. [Figure 4C] It is a top view of various additional embodiments of a battery pack assembly having a plurality of electrochemical cells of a first size. [Figure 4D] It is a top view of various additional embodiments of a battery pack assembly having a plurality of electrochemical cells of a first size. [Figure 4E] It is a top view of various additional embodiments of a battery pack assembly having a plurality of electrochemical cells of a first size. [Figure 5A] It is a top view of various additional embodiments of a battery pack assembly having a plurality of electrochemical cells of a second size. [Figure 5B] It is a top view of various additional embodiments of a battery pack assembly having a plurality of electrochemical cells of a second size. [Figure 5C] It is a top view of various additional embodiments of a battery pack assembly having a plurality of electrochemical cells of a second size. [Figure 5D] It is a top view of various additional embodiments of a battery pack assembly having a plurality of electrochemical cells of a second size. [Figure 6A] Figure 1 is a top view of various additional array configurations that may be used in the shape-fitting battery pack assembly, each array configuration containing a geometric shape with three or more bending axes. [Figure 6B] Figure 1 is a top view of various additional array configurations that may be used in the shape-fitting battery pack assembly, each array configuration containing a geometric shape with three or more bending axes. [Figure 6C] Figure 1 is a top view of various additional array configurations that may be used in the shape-fitting battery pack assembly, each array configuration containing a geometric shape with three or more bending axes. [Figure 6D] Figure 1 is a top view of various additional array configurations that may be used in the shape-fitting battery pack assembly, each array configuration containing a geometric shape with three or more bending axes. [Figure 6E] Figure 1 is a top view of various additional array configurations that may be used in the shape-fitting battery pack assembly, each array configuration containing a geometric shape with three or more bending axes. [Figure 7A] This is a side view of another embodiment of a shape-fitting battery pack assembly in which individual battery cells are inclined or perpendicular to the length dimension of the outer casing. [Figure 7B] This is a side view of another embodiment of a shape-fitting battery pack assembly in which individual battery cells are inclined or perpendicular to the length dimension of the outer casing. [Figure 7C] This is a side view of another embodiment of a shape-fitting battery pack assembly in which individual battery cells are inclined or perpendicular to the length dimension of the outer casing. [Figure 8] These are side and top views of another embodiment of a shape-fitting battery pack assembly including multiple stacked electrochemical cell arrays. [Figure 9] This is a schematic diagram of various appropriate electrical connections between individual electrochemical cells within a battery assembly, where the electrical connections are arranged on top of the individual electrochemical cells and connect the terminals of the cells. [Figure 10]This is a schematic diagram of the various electrical connections between individual electrochemical cells within a battery assembly, where the electrical connections are arranged on top of the individual electrochemical cells and connect each of the individual electrochemical cells to their respective cans. [Figure 11] This is a bottom view of an example of a battery pack assembly having electrical connections formed within the upper part of an electrochemical cell. [Figure 12] This is a top view of another example of a battery pack assembly having electrical connections formed within an electrochemical cell. [Figure 13] This is a top view of another battery pack assembly having a stacked flexible outer shell. [Figure 14] Figure 13 is a magnified view of the electrochemical cell in the battery pack assembly. [Figure 15] A wearable assembly including a sensor and battery pack assembly connected to a medical device is illustrated. [Figure 16] This is a graph of collected test data for one embodiment of a compatible battery pack. [Modes for carrying out the invention]

[0030] Electrochemical cells, or batteries, may be primary or secondary. Primary batteries are intended to be discharged only once (e.g., until empty) and then discarded. Primary batteries (or disposable batteries) are described, for example, in David Linden, Handbook of Batteries (4th edition, 2011). Secondary batteries (or rechargeable batteries) are intended to be recharged and reused. Secondary batteries may be discharged and recharged many times, for example, 50 or more, 100 or more, or more times. Secondary batteries are described, for example, in David Linden, Handbook of Batteries (4th edition, 2011). Therefore, batteries may include various combinations of electrochemical couples and electrolytes. The descriptions and examples provided herein apply to both aqueous, non-aqueous, ionic liquid, and solid-state primary and secondary batteries. Primary and secondary batteries of these systems may be used in the battery pack assemblies relating to this disclosure.

[0031] As used herein, the term “embedded and encapsulated by” refers to an individual item, such as a battery cell, that is completely embedded within a matrix of material such that there are substantially no gaps or spaces between the embedded item and the matrix of material (for example, the matrix of material contains less than 5 vol% of trapped air / gas). In other words, the matrix of material is in contact with the embedded object at substantially all locations outside the embedded object. Examples of processes for manufacturing an item embedded in and encapsulated by a matrix of material include, for example, overmolding, dipping, spraying, casting, and vapor deposition.

[0032] As used herein, the term “enclosed and encapsulated” refers to an item, such as a battery cell, being completely enclosed by a matrix of material, although small gaps or spaces may exist between the item and the surrounding matrix of material. Examples of processes for manufacturing enclosed and encapsulated items include, for example, lamination, vacuum forming, compression molding, powder coating, and joining by encapsulating the cell within an assembly of at least two pre-formed substrates and joining them at the seams using heat seals or adhesives.

[0033] As used herein, the terms “bending axis,” “multiple bending axes,” “axis of bending,” or “multiple bending axes” refer to one or more substantial straight lines passing through the flexible shell of the battery pack without contacting any battery cells within the flexible shell. One or more bending axes allow the flexible shell to deform or bend along the substantial straight lines, easily forming non-planar shapes, thereby significantly improving user comfort when the battery pack is in contact with the user's skin. One or more bending axes also allow the flexible shell to deform or bend to conform to the shape of a non-planar object. A substantial straight line is a line that deviates from the straight line by 20 degrees, preferably 15 degrees, or less, from the straight line, which is formed by drawing a straight line between the two endpoints of the bending axis at the periphery of the flexible shell. The deviation is measured by establishing an angled cone starting at one of the endpoints, which diverges by 20 degrees (or 15 degrees) to either side of the ideal line, such that the bending axis is contained within this cone along its entire length. The material within the flexible shell is preferably adapted to deform along the substantially straight line in response to the bending force applied to the flexible shell. The bending axis may stretch along the length, width, and / or thickness dimensions of the flexible shell. In some cases, the axis of symmetry may be the bending axis if it does not intersect or overlap with the battery cells disposed within the flexible shell.

[0034] As used herein, the term “electronic component” refers to any device that is powered by electricity. Examples of electronic components include processors, microprocessors, signal processors, integrated circuits, displays, capacitors, resistors, transistors, medical devices (such as glucose delivery devices or automated defibrillators), global positioning system (GPS) receivers, sensors (such as biometric sensors, temperature sensors, accelerometers, moisture sensors), antennas, and combinations thereof.

[0035] Many wearable electronic devices require a self-contained portable power source. Typically, power is supplied by an electrochemical battery cell or a portable battery pack assembly. However, existing electrochemical battery cells and battery pack assemblies often lack sufficient flexibility and elasticity to be comfortable when attached to human skin, and therefore frequently cause discomfort to the user.

[0036] Known battery assemblies, which include multiple cells with upper and lower laminate layers bonded together using adhesive, generally lack flexibility, stretchability, and shape conformability.

[0037] The battery pack assemblies described herein offer a wide range of power characteristics while being flexible and shape-conforming to suitably enhance user comfort. The battery pack assemblies described herein also include a protective flexible outer shell having a skin-like feel, which extends the length of time the battery pack assembly can be comfortably tolerated when worn, by further suitably enhancing user comfort. Furthermore, the battery pack assemblies described herein may be incorporated into clothing such as wristbands, belts, suspenders, headbands, armbands, socks, vests, or other smart clothing in general to provide additional energy storage for rechargeable devices, health and fitness equipment, other sensors, audio equipment, and mobile phone power. Because the battery pack assemblies described herein can completely enclose individual electrochemical cells within a matrix of waterproof, shape-conforming material, smart clothing incorporating the disclosed battery pack assemblies can be suitably and safely washed without removing the electrochemical cells.

[0038] The disclosed battery pack assemblies may include any type of electrochemical cell, but in some examples, relatively low-cost coin or button electrochemical cells of any chemical reaction (including, for example, primary lithium, Zn-Ag2O, and Zn-MnO2) may be preferably used. In other embodiments, the electrochemical cell may include cylindrical, rectangular, or pouch cells. In yet another embodiment, the electrochemical cell may have other shapes such as rectangular or square.

[0039] Referring here to Figures 1-3, an example of a shape-conforming battery pack assembly 10 according to the present disclosure includes an array of individual electrochemical cells 12 that are electrically connected to one another. The array of individual electrochemical cells 12 is embedded and encapsulated within a matrix of shape-conforming material 14 that forms a protective flexible shell 16. This protects the cells from the ambient air and provides a shape-conforming material that improves user experience and comfort when the battery pack assembly is mounted. In the illustrated embodiment, an opening 22 is formed into which an electronic component 20 is optionally included. The electronic component 20 may include one or more of the following: a processor, microprocessor, signal processor, integrated circuit, display, capacitor, resistor, transistor, sensor, medical device such as a glucose delivery device or automatic defibrillator, global positioning system (GPS) receiver, sensor (biometric sensor, temperature sensor, accelerometer, moisture sensor, etc.), induction coil, or antenna. Furthermore, in some embodiments, the antenna may also function as an induction coil that converts a time-varying magnetic or electric field into a DC current for battery charging. In some embodiments, the electronic component 20 may be a sensor that comes into direct contact with the user's skin. In other embodiments, the electronic component 20 may be located in a separate compartment, embedded in a shape-fitting material 14, and encapsulated. Even in this case, the electronic component 20 is electrically connected to one or more electrochemical cells 12 to receive power. The electronic component 20 is an optional component. In other embodiments, the shape-fitting battery pack assembly 10 may be used to power other devices that are not sensors.

[0040] In some embodiments, electronic components may be connected to the surface of the cell 12, or may be located within the matrix of the shape-conforming material 14 between the cells 12, or between one cell 12 and the outer surface of the matrix of the shape-conforming material 14 (for example, they may be embedded and encapsulated by the matrix of the shape-conforming material, or surrounded and encapsulated). An array of electronic components and individual electrochemical cells 12 may be embedded within the matrix of the shape-conforming material 12 and encapsulated by the matrix, for example, by molding or by covering with a film, to form an entire electronic device / battery assembly. In yet another embodiment, a stretchable (elastomer) circuit having conductors and components may also be embedded within the matrix of the shape-conforming material 14 and encapsulated by the matrix. Such embodiments produce a single, integrated flexible / elastic unit containing both electronic components and power sources (electrochemical cells 12), all of which are protected by the matrix of the shape-conforming material 14.

[0041] In some embodiments, the electrochemical cells 12 are connected in series and in parallel by flexible conductors 24 that electrically connect each electrochemical cell 12. An exemplary embodiment includes two flexible conductors 24 at the top, one connecting the negative terminal of the first group 12b of the electrochemical cell 12 and the other connecting the positive terminal of the second group 12a of the electrochemical cell 12 (Figure 1), and one flexible conductor 24 at the bottom connecting the negative terminal of the second group 12a of the electrochemical cell 12 to the positive terminal of the first group 12b of the electrochemical cell 12 (Figure 2), although the flexible conductors are for illustrative purposes only. Thus, the electrochemical cells 12 can be electrically connected in series, in parallel, or in series and parallel by the flexible conductors 24, as is known in the art, depending on the requirements of power, capacity, and / or voltage. The electrochemical cell 12 may be connected to a device requiring power using one or more external terminals 26.

[0042] If an electronic component 20 is included, it may be virtually any type of electronic component, such as a sensor. In some embodiments, the electronic component 20 may be a physiological sensor that measures a physiological characteristic or state. Typical examples of sensors 20 include, but are not limited to, heart rate sensors, EKG sensors, nerve impulse sensors, glucose sensors, electrical skin response sensors, hydration sensors, sweat sensors, and body temperature sensors, and virtually any type of sensor may be used. The battery pack assembly 10 may also further include structures or medical devices that can provide treatment for a sensed state, as further described with reference to Figure 15, such as a drug delivery system activated by a signal from the electronic component 20 (e.g., insulin injection in response to glucose monitoring), electrotherapy such as defibrillation for abnormal heart rates, wound sterilization, and healing (e.g., bone growth stimulation).

[0043] In other embodiments, the electronic component 20 may be a position sensor or a biometric sensor. Typical sensors include, but are not limited to, GPS sensors, accelerometers, gyroscopes, and pedometers. In a typical example, these types of sensors may be used in a battery pack assembly combined with sportswear to monitor sports performance. In another embodiment, a shape-conforming battery pack with a position sensor, accelerometer, and / or humidity sensor may be mounted on a non-planar surface of a package for tracking luggage.

[0044] The flexible outer shell 16 comprises an outer shell material having a skin-like feel to improve and promote user comfort. The outer shell material includes a material having one or more of the following: a break elongation ratio of 1.1 to 1.8, preferably 1.2 to 1.7, more preferably 1.3 to 1.6; a maximum tensile strength of 1 to 50 MPa, preferably 15 to 40 MPa, more preferably 20 to 40 MPa, more preferably 25 to 35 MPa; and a Young's modulus of 5 kPa to 140 MPa, preferably 20 to 100 MPa, more preferably 30 to 80 MPa.

[0045] In some embodiments, the outer shell material has a hardness value of HOOO-S 10 to 90A, preferably HOO-5 to 30A, and more preferably HOO-10 to HOO-50, as defined by ASTM standard D2240-15. In other embodiments, the hardness may be greater than HOOO-S 10 or less than 90A, but preferably HOOO-S 10 to 90A.

[0046] In some embodiments, the outer shell material has an elongation fracture of 350% to 1,000%, preferably 500% to 900%, more preferably 600% to 900%, and more preferably about 900%. In other embodiments, the elongation fracture may be higher than 350% or less than 1,000%, but preferably 100% to 1500%.

[0047] In some embodiments, the outer shell material has a 100% modulus of less than 86 psi (i.e., tensile stress at 100% elongation), preferably 8 psi to 86 psi, more preferably about 10 psi.

[0048] In some embodiments, the outer shell material has a tensile strength of less than 50 MPa or greater than 15 MPa, preferably 15 to 40 MPa, and more preferably about 25 MPa.

[0049] In some embodiments, the shell material comprises an elastomer. Individual electrochemical cells 12 may be embedded and encapsulated using an elastomer in the form of a liquid precursor, which can be done, for example, by injecting the liquid elastomer into a mold containing electrochemical cells 12 connected to each other by a flexible conductor 24, and then curing the elastomer (for example, by drying or heating, or by curing a two-component liquid elastomer over time and / or by temperature, or by exposure to UV light or radiation). Alternatively, the liquid elastomer may be applied by dipping or spraying the electrochemical cells 12, and then initiating the curing process. In some embodiments, casting-friendly silicone rubber, similar to that used for skin effects and cinematic effects, may be particularly advantageous. Suitable silicone rubbers for casting include, but are not limited to, BODY DOUBLE® Silk (Bentley Advanced Materials), BODY DOUBLE® Standard Set (Bentley Advanced Materials), PlatSil® Gel (Polytek Development Corp.), ECO-FLEX® Series Silicone Rubber (Smooth On, Inc.), Smooth-On Dragon Skin® (Smooth-On, Inc.), or ELASTOSIL® RTV-2 (Wacker). Other materials, including other silicones or other materials having the properties described herein, may also be used. In other embodiments, the array of electrochemical cells may be embedded and encapsulated using a hot-melt adhesive or low-pressure molding material, such as Henkel Technomelt® AS8998 polyolefin hot-melt adhesive having an elongation fracture of 733% and a Shore hardness of 10A.

[0050] Encapsulation can also be achieved by covering the electrochemical cells 12 with a thin sheet of elastomer substrate held together with an adhesive. In some embodiments, the boundaries of the substrate and / or the area around the edges of the battery may be heat-sealed to fix the electrochemical cells 12 in place. For example, the electrochemical cells 12 may be placed on a thin elastomer sheet coated with adhesive and then wired together by flexible conductors 24. Another layer of adhesive-coated elastomer film may then be pressed onto the electrochemical cells 12. This provides a matrix of shape-conforming material that completely surrounds and encapsulates the electrochemical cells 12. The flexible conductors 24 may exit the encapsulation along the bonding lines between two adjacent adhesive layers or at other desired locations. In some embodiments, an array of electrochemical cells can be surrounded and encapsulated using tape such as 3M Schotchwrap® tape 50 with a 200% elongation break or 3M Industrial Protective Film 7070UV with a 635% elongation break.

[0051] In some embodiments, the flexible shell material is laminated around individual electrochemical cells 12 so that the individual electrochemical cells 12 are surrounded and encapsulated by the shell material, as shown in Figures 13 and 14. In other embodiments, the shell material is molded around individual electrochemical cells 12 so that the individual electrochemical cells 12 are embedded and encapsulated by the shell material, as shown in Figures 1-3.

[0052] In some embodiments, the outer shell material has adhesive 30 (Figure 3) on one or both sides.

[0053] Referring here to Figures 4A-4E, the disclosed battery pack assembly 10 can have virtually countless shapes and electrochemical cell 12 array configurations. For example, in the case of an electrochemical cell 12 having a first size or diameter, the shell material 16 may have a substantially rectangular shape, or a more elliptical / elliptical or circular shape (however other shapes are also possible). Individual electrochemical cells 12 may be arranged to have a symmetrical or asymmetrical layout (as shown). The flexible shell material 16 may include openings 22 for sensors. The electrochemical cells 12 may be arranged such that the array has one or more axes of symmetry. Preferably, the array has at least three or more axes of symmetry. For example, the array may have a first axis of symmetry A, a second axis of symmetry B, a third axis of symmetry C, and a fourth axis of symmetry D, as shown in Figure 4D. All axes of symmetry may be non-parallel to each other. In other embodiments, two or more axes of symmetry may be parallel but separated from each other (e.g., axes of symmetry E and F in Figure 4E). In yet another embodiment, more than four or fewer axes of symmetry may be formed.

[0054] As shown in Figures 5A–5D, if electrochemical cells 12 having a second size or diameter (here relatively smaller than the electrochemical cell 12 shown in Figure 4) are used, the disclosed battery pack assembly 10 may have different electrochemical cell 12 array configurations. Although the shape of the flexible shell material 16 can be virtually infinite, if smaller electrochemical cells 12 are used, as in the embodiments of Figures 4A–4E, the individual electrochemical cells 12 can be combined and packed more densely, so that the individual electrochemical cells 12 can be arranged within a given volume of the shell material 16. In other embodiments, the battery pack assembly may include a mixture of multiple electrochemical battery cells having different sizes and / or shapes. Similar to the embodiments of Figures 4A–4E, the embodiments of Figures 5A–5D may also include an opening 22 for a sensor.

[0055] Returning to Figure 4D, if an axis of symmetry does not include the electrochemical cell 12 or does not overlap with the electrochemical cell 12, that axis of symmetry may also form a bending axis. For example, axes of symmetry B, C, and D also form bending axes. However, axis of symmetry A abuts the electrochemical cell 12, and the electrochemical cell 12 resists bending of the flexible outer shell 16 around axis of symmetry A, so axis of symmetry A does not form a bending axis.

[0056] As particularly illustrated in Figures 4A to 4D, individual cells may be spaced apart from each other by 5% to 100%, preferably 10% to 100%, and more preferably 15% to 100%, of the average cell diameter. In other embodiments where the individual cells have a rectangular or square shape, the individual cells may be spaced apart from each other by 5% to 100%, preferably 10% to 100%, of the maximum straight-line dimension of the individual cell. Spacing within these ranges enhances the flexibility and shape conformability of the battery pack.

[0057] Additionally, the flexible outer shell may have a thickness-to-length ratio of 1:2 to 1:30, preferably 1:5 to 1:20, and more preferably 1:10 to 1:15.

[0058] Generally, an increase in the number of bending axes accommodates more skin bending modes and, therefore advantageously, provides a more comfortable fit for the user. For example, circular, hexagonal, or octagonal (more generally polygonal) arrays may be preferred, such as the arrays shown in Figures 4C and 4D and Figures 6D and 6E. Slits, cuts, or perforations within the outer shell material 16 can provide greater flexibility or elasticity to the battery pack assembly 10. For example, the slits, cuts, or perforations 42 shown in Figure 4E may be created between adjacent cells, and for example, the slits may preferably be equidistant from the bending axes, located between the bending axes, or positioned along the bending axes, in which case shape conformability is improved. Alternatively, they may be created at other locations that reduce stress within the encapsulation material and lessen the force required to bend or stretch the battery pack assembly 10.

[0059] Figures 6A–6C show several examples of rectangular arrays, Figure 6D shows a hexagonal array, and Figure 6E shows a circular array. The hexagonal array of electrochemical cells 12 in Figure 6D includes at least three non-parallel bending axes (A, B, and C), and the circular array of electrochemical cells 12 in Figure 6E includes at least four non-parallel bending axes (A, B, C, and D).

[0060] Figures 7A–7C show other rope-type embodiments of the shape-fitting battery pack assembly. The embodiments shown in Figures 7A–7C may be formed as relatively long and thin shapes similar to ropes. In these embodiments, the individual electrochemical cells are oriented at an angle less than or equal to the perpendicular dimension of the shell 16. The rope-type embodiments are flexible and elastic. In other words, these embodiments are preferably bent and stretched simultaneously. The rope-type embodiments may be configured to balance cell size and spacing. The embodiments in Figures 7A–7C show individual battery cells connected in series, but in other embodiments, the individual battery cells may be connected in series, in parallel, or in a combination of series and parallel.

[0061] Figure 8 shows another embodiment of a shape-conforming battery assembly comprising two separate battery cell arrays, namely a first array 12a and a second array 12b. Each array occupies a separate parallel plane. The first array 12a is positioned adjacent to the second array 12b, and the individual cells 12 in the second array 12b are offset from the individual cells in the first array. When individual cells 12 are offset from each other in various layers, flexibility can be enhanced by providing gaps or planar slits between the arrays. In other embodiments, individual cells in the second array 12b may be located directly above or directly below individual cells in the first array 12a.

[0062] Referring here to Figures 9 and 10, various types of electrical connections between electrochemical cells 12 are shown. In some embodiments, as shown in Figure 9, a flexible conductor 24 may be formed between the poles of individual electrochemical cells 12 on the top and / or bottom of the electrochemical cell 12. The flexible conductor 24 may have various stress-relieving shapes such as loops, offsets, curves, coils, helical shapes, bends, corkscrews, and arcs, which is advantageous in reducing material stress when the battery pack assembly 10 is bent, folded, or stretched. Similarly, as shown in Figure 10, the flexible conductor 24 may be formed between the sides of individual electrochemical cells 12 (for example, since the cans of the electrochemical cells are typically electrically connected to the poles), and the flexible conductor 24 may similarly take on stress-relieving shapes such as loops, offsets, curves, coils, helical shapes, bends, corkscrews, and arcs.

[0063] The flexible conductor 24 may include a highly conductive material that is flexible and does not crack when repeatedly bent. These types of materials give the longest usable life of the battery pack assembly 10, in particular when the material is formed to provide the conductor 24 with the stress-relieving shape described above. In some embodiments, the flexible conductor 24 may include copper, nickel, stainless steel, brass, other metals or alloys, carbon fiber, conductive polymers, or combinations of these materials. The conductor is relatively thin, allowing for maximum flexibility without unacceptable voltage loss during discharge or charging. In some embodiments, the conductor may include a 36-gauge enameled copper magnet wire with a diameter of about 0.14 mm. However, a diameter of about 0.05 mm to about 0.5 mm has been found to strike a balance between flexibility and fatigue failure. Advantageously, flexible conductors with thicknesses within the disclosed range are generally more fatigue-resistant because the flexible conductor is supported by a flexible shell. Furthermore, this support allows for the use of smaller gauge wires than would be possible if the flexible conductor were exposed and not supported by the matrix material, thereby enhancing the flexibility and elastic properties of the battery pack assembly.

[0064] The flexible conductor 24 can be attached to the electrochemical cell 12 in various ways, such as by resistance welding, ultrasonic welding, laser welding, brazing, soldering, or by using a conductive polymer or adhesive.

[0065] Figures 11 and 12 illustrate one embodiment of a battery pack assembly 10 comprising an array of electrochemical cells 12 embedded in a matrix of shape-conforming material and encapsulated by the matrix. In Figure 11, the flexible conductors 24 on top of the electrochemical cells, which would otherwise be visible through the transparent or translucent shape-conforming material, are omitted for clarity. The embodiments in Figures 11 and 12 can be formed, for example, by molding a matrix of shape-conforming material around an array of electrochemical cells 12. The electrochemical cells 12 in the array are electrically connected by flexible conductors 24, as generally discussed above, and the flexible conductors 24 are further connected to terminals. Advantageously, the battery pack assembly 10 can be stretched or twisted without damaging the electrochemical cells 12 or the flexible conductors 24. Furthermore, stretching and / or twisting advantageously allow the battery pack assembly 10 to conform to another surface, for example, a part of the human body.

[0066] Figures 13 and 14 illustrate another embodiment of the battery pack assembly 10, comprising an array of electrochemical cells 12 surrounded and encapsulated by a shape-conforming material. The embodiments of Figures 13 and 14 may be formed, for example, by laminating an array of electrochemical cells 12 between two sheets of material. The array of electrochemical cells 12 is electrically connected by flexible conductors 24, as generally described above. Advantageously, the battery pack assembly 10 can be stretched or twisted without damaging the electrochemical cells 12 or the flexible conductors 24. Furthermore, stretching and / or twisting advantageously allow the battery pack assembly 10 to conform to the shape of another surface, for example, a part of the human body.

[0067] Referring next to Figure 15, an example of a wearable garment 100 including a battery pack assembly 10 according to the present disclosure is shown. The battery pack assembly 10 may be positioned at any point on the wearable garment 100, and the battery pack assembly 10 adjusts its shape to conform to the position on the body beneath it. The battery pack assembly 10 includes an array of individual electrochemical cells 12 and electronic components 20. The electronic components 20 may include physiological sensors as described above. The electronic components 20 may be communicatively connected to a medical device 200, such as the medical device described above. If necessary, the medical device 200 monitors the condition and / or administers drug therapy in response to readings from the electronic components 20.

[0068] Example 1 Next, with reference to Figure 16, the impact of shell expansion and bending on battery performance is shown. The test configuration included an array of eight SR616 silver oxide button cells in a 2 series × 4 parallel configuration, similar to the arrangement shown in Figure 5C, but with a total of eight cells instead of the ten shown in Figure 5C. The cells were connected by 36-gauge enameled insulated copper wire, bent into a meandering shape, and resistance welded to the cell terminals. The assembly was embedded and encapsulated in silicone rubber, specifically Smooth-On Dragon Skin® FX-Pro, a silicone rubber with a Shore A hardness of 2A, a 100% modulus of 37.8 psi, a 763% elongation break, and a maximum tensile strength of 288 psi.

[0069] The control assembly was continuously discharged at 0.8mA at room temperature until it reached a voltage of 2.0V.

[0070] Stretching: The assembly was stretched for 5,000 consecutive cycles along the length dimension of the outer shell by 10% more than the relaxed dimension. After 5,000 cycles, the assembly was discharged continuously at 0.8 mA at room temperature until it reached a voltage of 2.0 V.

[0071] Bending: The assembly was bent on a 0.625-inch diameter mandrel and then relaxed to its normal shape. The bending cycle was performed continuously at a rate of 22 cycles / minute until 5,000 cycles were achieved. After 5,000 cycles, the battery was continuously discharged at 0.8mA at room temperature until it reached a voltage of 2.0V.

[0072] As shown in Figure 16, the test results indicate that stretching and bending did not significantly affect the electrical performance of the battery assembly. In fact, there was virtually no difference in electrical performance between the control assembly and the stretched and bent assemblies. Therefore, individual battery cells were advantageously protected from environmental factors and surrounded by a skin-like material without affecting their electrical performance.

[0073] While specific electrochemical cell 12 array configurations are shown herein, electrochemical cells 12 spaced substantially regularly apart provide relatively uniform overall mechanical properties and are therefore generally preferred by the user in one embodiment. The specific geometric arrangement of the electrochemical cells 12, particularly three or more axes of symmetry, combined with the size and geometric shape of the outer shell material, which is optionally adapted to the specific application, as well as the size and geometric shape of the electrical interconnections between cells, especially the stress-relieving shapes described above, improves the flexibility and elasticity of the battery assembly, thereby providing the user with greater comfort, as well as enhanced wearability and functionality. Individual electrochemical cells within the array may be the same or different sizes and may be circular, elliptical, rectangular, or any other preferred shape. Depending on the application requirements, the battery pack assembly 10 can take virtually any external form and may have one or more through-holes located at various positions. This can be provided, for example, by omitting the electrochemical cell 12 at a desired position in the hole, or by cutting a hole in a desired space between the electrochemical cells 12 so that a sensor can be placed in the resulting hole and come into direct contact with the user's skin.

[0074] The disclosed battery pack assemblies are relatively thin and possess mechanical properties sufficiently similar to skin to feel comfortable when attached to the human body with a suitable adhesive. These battery pack assemblies facilitate skin-mounted sensors or other devices that cause less irritation and discomfort to the user and can be worn for longer periods. The disclosed battery pack assemblies advantageously provide a continuous and uninterrupted interconnection between battery contacts and sensor contacts. Although stated to facilitate skin contact, it should be understood that the disclosed battery pack assemblies do not need to be used in this manner and can instead be incorporated into clothing, such as an armband or the article shown in Figure 15. The skin-like feel allows the disclosed battery assembly to bend and behave in a way that allows it to move when worn by a user, thus enhancing user comfort and thus promoting long-term compliance and use. Furthermore, the disclosed battery assembly advantageously protects the cells and electrical connections from environmental factors such as temperature changes, liquids, dirt, and dust, while substantially maintaining the electrical performance of the battery cells.

[0075] The dimensions and values ​​disclosed herein should not be understood as being strictly limited to the exact numerical values ​​listed. Instead, unless otherwise specified, each such dimension is intended to mean both the listed value and a functionally equivalent range around that value. For example, a dimension disclosed as "40 mm" is intended to mean "approximately 40 mm".

[0076] All documents referenced herein (including any cross-references or related patents or applications, and any patents or applications to which this application claims priority or benefit thereof) are incorporated herein by reference in their entirety unless expressly excluded or otherwise limited. The reference of any document does not constitute prior art to any invention disclosed or claimed herein, nor does it constitute teaching, suggestion, or disclosure of any such invention, either alone or in combination with any one or more other references. Furthermore, in the event of any conflict between the meaning or definition of any term in this document and any meaning or definition of the same term in any document incorporated by reference, the meaning or definition assigned to the term in this document shall prevail.

[0077] While specific embodiments of the present invention have been illustrated and described, it will be apparent to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the appended claims are intended to encompass all such changes and modifications that fall within the scope of the invention.

Claims

1. A shape-conforming battery pack assembly, An array of individual electrochemical cells electrically connected to one another, wherein the array is enclosed by a flexible shell and encapsulated, The array is geometrically arranged such that there are at least three non-parallel bending axes. A shape-conforming battery pack assembly in which the array of individual electrochemical cells comprises a first array and a second array, the first array and the second array occupy separate parallel planes, and the individual cells are offset from each other between the parallel planes.

2. The shape-matching battery pack assembly according to claim 1, wherein the array has a circular or hexagonal array shape.

3. The shape-conforming battery pack assembly according to claim 1 or 2, wherein the array includes an opening in the array and a sensor located within the opening, the sensor being electrically connected to the array of cells.

4. The shape-conforming battery pack assembly according to any one of claims 1 to 3, wherein the battery array is configured to generate more than 20 mAh at a nominal 3.0 V.

5. The shape-conforming battery pack assembly according to any one of claims 1 to 4, further comprising slits or perforations in the outer shell to facilitate bending.

6. The shape-conforming battery pack assembly according to claim 5, wherein at least one slit or perforation substantially overlaps with at least one bending axis and thus corresponds to the at least one bending axis.

7. The shape-conforming battery pack assembly according to claim 5, wherein each of the at least three non-parallel bending axes includes a corresponding perforation or slit along the axis.

8. The shape-conforming battery pack assembly according to any one of claims 1 to 7, wherein the electrical connections between cells include a highly conductive flexible material.

9. The shape-conforming battery pack assembly according to any one of claims 1 to 8, wherein the electrical connection is in one shape of a loop, offset, helical, or meandering in order to improve flexibility.

10. The shape-conforming battery pack assembly according to any one of claims 1 to 9, wherein the electrical connection connects one of the top, bottom, or side of the cell.

11. The shape-conforming battery pack assembly according to any one of claims 1 to 10, wherein the electrical connections are made by thermal welding, resistance welding, laser welding, or ultrasonic welding.

12. The shape-conforming battery pack assembly according to any one of claims 1 to 11, wherein the electrical connections are soldered, brazed, bonded with a conductive adhesive, or held together by mechanical pressure.

13. The shape-conforming battery pack assembly according to any one of claims 1 to 12, wherein the electrical connection has a circular or rectangular cross-sectional shape.

14. A shape-conforming battery pack assembly, An array of individual electrochemical cells electrically connected to one another, wherein the array is enclosed by a flexible shell and encapsulated, A shape-conforming battery pack assembly in which the electrical connections between cells are configured to allow stretching and / or bending and / or torsion over a planned number of bending cycles without exceeding the fatigue limit stress to the electrical connections, thereby reducing material stress.

15. The shape-conforming battery pack assembly according to claim 14, wherein the electrical connections between cells include a highly conductive flexible material.

16. The shape-conforming battery pack assembly according to claim 14 or 15, wherein the electrical connection is in one of the shapes of a loop, offset, helical, or meandering in order to improve flexibility.

17. The shape-conforming battery pack assembly according to any one of claims 14 to 16, wherein the electrical connection connects one of the top, bottom, or side of the cell.

18. The shape-conforming battery pack assembly according to any one of claims 14 to 17, wherein the electrical connections are made by thermal welding, resistance welding, laser welding, or ultrasonic welding.

19. The shape-conforming battery pack assembly according to any one of claims 14 to 18, wherein the electrical connections are soldered, brazed, bonded with a conductive adhesive, or held together by mechanical pressure.

20. The shape-conforming battery pack assembly according to any one of claims 14 to 19, wherein the electrical connection has a circular or rectangular cross-sectional shape.

21. The shape-adaptive battery pack assembly according to any one of claims 14 to 20, wherein the array has a circular or polygonal array shape.

22. The shape-conforming battery pack assembly according to any one of claims 14 to 21, wherein the array includes an opening in the array and a sensor located within the opening, the sensor being electrically connected to the array of cells.

23. The shape-conforming battery pack assembly according to any one of claims 14 to 22, wherein the battery array is configured to generate more than 20 mAh at a nominal 3.0 V.

24. A shape-conforming battery pack assembly according to any one of claims 14 to 23, further comprising perforations within the outer shell to facilitate bending.

25. The shape-conforming battery pack assembly according to claim 24, wherein the perforation is a slit.

26. A shape-conforming battery pack assembly, An array of individual electrochemical cells electrically connected to each other, wherein the array is enclosed by a flexible outer shell and encapsulated, An electronic component operably connected to the array of individual electrochemical cells, wherein the electronic component is enclosed and encapsulated by the flexible outer shell, The array is geometrically arranged such that at least three non-parallel bending axes are present in the shape-conforming battery pack assembly.

27. The shape-conforming battery pack assembly according to claim 26, wherein the electronic components include one or more of the following: a processor, a microprocessor, a signal processor, an integrated circuit, a display, a capacitor, a resistor, a transistor, a medical device such as a glucose delivery device or an automated defibrillator, a global positioning system (GPS) receiver, a sensor (such as a biometric sensor, a temperature sensor, an accelerometer, a moisture sensor, etc.), or an antenna.

28. The shape-conforming battery pack assembly according to claim 26 or 27, wherein the electronic component is operably connected to the face of one electrochemical cell in the array of individual electrochemical cells.

29. The shape-conforming battery pack assembly according to any one of claims 26 to 28, wherein the electronic component is positioned within the flexible outer shell.

30. The shape-conforming battery pack assembly according to any one of claims 26 to 28, wherein the electronic components are enclosed and encapsulated by the flexible outer shell.

31. The shape-conforming battery pack assembly according to claim 14, wherein the electrical connection includes a wire having a diameter of 0.05 mm to 0.5 mm.

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