Battery cell designs for improved charge rate and temperature regulation

Abstract

A battery cell includes a shaft disposed in an orthogonal orientation relative to a plane of a first electrode, a second electrode, and a separator interposed between the first electrode and the second electrode. The first electrode includes one or more layers of a first electrode active material having at least one dimension smaller than a corresponding dimension of the first current collector such that an outer perimeter of the first current collector is exposed to form a peripheral tab in electrical contact with a case of the battery cell. The second electrode includes one or more layers of a second electrode active material having at least on dimension that is smaller than a corresponding dimension of the second current collector such that an inner perimeter of the second current collector is exposed to form a central tab in electrical contact with the shaft.

Description

BATTERY CELL DESIGNS FOR IMPROVED CHARGE RATE AND TEMPERATURE REGULATIONCROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to U.S. Provisional Application No. 63 / 693,939, entitled “BATTERY CELL DESIGN FOR IMPROVED CHARGE RATE AND TEMPERATURE CONTROL” and filed on September 12, 2024, the disclosure of which is incorporated herein by reference in its entirety.TECHNICAL FIELD

[0002] The subject matter described herein relates generally to battery technology and more specifically to battery cell designs for improved charge rate and temperature regulation.BACKGROUND

[0003] Batteries are a form of electrochemical energy storage system in which energy is stored in the form of chemical reactions at the electrodes. This chemical energy is converted into electrical energy through a reduction oxidation (redox) reaction, a type of faradic process governed by Faraday’s law. For example, during the charging and discharging of a battery cell, the faradic process (e.g., a reduction oxidation (redox) reaction) occurring at the electrodeelectrolyte interface causes a transfer charge (or electrons) therebetween. When the battery cell is discharged, ions migrate from the negative electrode (or anode) to the positive electrode (or cathode) of the battery cell while electrons flow through an external circuit from the negative electrode (or anode) to the positive electrode (or cathode). The movement of electrons (or the flow electric charge or current), driven by a voltage source in the form of the discharging battery cell, may power an electrical load. Conversely, during the charging of the battery cell, an external power source forces ions and electrons to move in the opposite direction. For instance, while the battery cell is being charged, electrons return from the positive electrode(or cathode) to the negative electrode (or anode) while ions migrate from the positive electrode(or cathode) back to the negative electrode (or anode) of the battery cell.SUMMARY

[0004] Systems, methods, and articles of manufacture, including battery cells and battery cell components, are provided. In some implementations of the current subject matter, there is provided a battery cell that includes: a case enclosing a shaft, a first electrode, a second electrode having an opposite polarity as the first electrode, and a first separator interposed between the first electrode and the second electrode, wherein the shaft is disposed in an orthogonal orientation relative to a plane of the first electrode, the second electrode, and the first separator, the first electrode includes one or more layers of a first electrode active material disposed on one or more surfaces of a first current collector, the one or more layers of the first electrode active material having at least one dimension that is smaller than a corresponding dimension of the first current collector such that an outer perimeter of the first current collector is exposed, and an exposed outer perimeter of the first current collector forming a peripheral tab in electrical contact with the case of the battery cell, and the second electrode includes one or more layers of a second electrode active material disposed on one or more surfaces of a second current collector, the one or more layers of the second electrode active material having at least one dimension that is smaller than a corresponding dimension of the second current collector such that an inner perimeter of the second current collector is exposed, and an exposed inner perimeter of the second current collector forming a central tab in electrical contact with the shaft.

[0005] In some variations of the battery cell, one or more of the following features can optionally be included in any feasible combination.

[0006] In some variations, at least one of the shaft and the case of the battery cell comprises a heat sink that absorbs and dissipates heat generated by the electrodes.

[0007] In some variations, the shaft comprises a hollow tube filled by one or more coolants.

[0008] In some variations, the one or more coolants include a gas coolant, a liquid coolant, and / or a solid coolant.

[0009] In some variations, the shaft comprise a solid bar formed from one or more thermally conductive materials.

[0010] In some variations, the perimeter tab is secured to the case of the battery cell by welding or soldering.

[0011] In some variations, the central tab is secured to the shaft by welding or soldering.

[0012] In some variations, an outer surface of the shaft includes one or more slots for receiving one or more central tabs.

[0013] In some variations, an inner surface of the case includes one or more slots for receiving one or more peripheral tabs.

[0014] In some variations, the battery cell further includes one or more additional shafts disposed in the orthogonal orientation relative to a plane of the first electrode, the second electrode, and the first separator.

[0015] In some variations, the battery cell includes a quantity of shafts proportional to one or more dimensions of the battery cell.

[0016] In some variations, the quantity of shafts is proportional to an area of a cross section parallel to the plane of the first electrode, the second electrode, and the first separator.

[0017] In some variations, the battery cell include one, two, three, four, five, six, or seven shafts.

[0018] In some variations, the case further encloses a third electrode having a same polarity as the first electrode but an opposite polarity as the second electrode. The third electrode includes one or more layers of the first electrode active material disposed on one or more surfaces of a third current collector. The one or more layers of the first electrode active material have at least one dimension that is smaller than a corresponding dimension of the third current collector such that an outer perimeter of the third current collector is exposed. An exposed outer perimeter of the third current collector forms an additional peripheral tab in electrical contact with the case of the battery cell.

[0019] In some variations, the case further encloses a fourth electrode having an opposite polarity as the third electrode. The fourth electrode includes one or more layers of the second electrode active material disposed on one or more surfaces of a fourth current collector. The one or more layers of the second electrode active material have at least one dimension that is smaller than a corresponding dimension of the fourth current collector such that an inner perimeter of the fourth current collector is exposed. An exposed inner perimeter of the fourth current collector forms an additional central tab in electrical contact with the shaft of the battery cell.

[0020] In some variations, the one or more layers of the first electrode active material, the first current collector, the one or more layers of the second electrode active material, the second current collector, and the first separator comprise a plurality of concentric layers.

[0021] In some variations, the plurality of concentric layers share a common axis comprising the shaft.

[0022] In some variations, the separator comprises a rigid separator.

[0023] In some variations, the separator comprises a ceramic-based separator.

[0024] In some variations, the separator comprises a solid state electrolyte.

[0025] In some variations, the case further encloses one or more of a liquid electrolyte, a gel electrolyte, and a solid electrolyte.

[0026] The details of one or more variations of the subject matter described herein are set forth in the accompanying drawings and the description below. Other features and advantages of the subject matter described herein will be apparent from the description and drawings, and from the claims. While certain features of the currently disclosed subject matter are described for illustrative purposes in relation to metal ion battery cells, such as lithium ion battery cells, it should be readily understood that such features are not intended to be limiting. The claims that follow this disclosure are intended to define the scope of the protected subject matter.DESCRIPTION OF DRAWINGS

[0027] The accompanying drawings, which are incorporated in and constitute a part of this specification, show certain aspects of the subject matter disclosed herein and, together with the description, help explain some of the principles associated with the disclosed implementations. In the drawings,

[0028] FIG. 1A depicts a schematic diagram illustrating an example of a battery cell with single tab design, in accordance with some example embodiments;

[0029] FIG. IB depicts a schematic diagram illustrating an example of a battery cell with a multi-tab (or all-tab) design, in accordance with some example embodiments;

[0030] FIG. 2A depicts a vertical cross sectional view of an example of a battery cell with a concentric tab design, in accordance with some example embodiments;

[0031] FIG. 2B depicts a transparent perspective view of an example of a battery cell with a concentric tab design, in accordance with some example embodiments;

[0032] FIG. 2C depicts a transparent perspective view of another example of a battery cell with a concentric tab design, in accordance with some example embodiments;

[0033] FIG. 2D depicts a horizontal cross sectional view of an example of a battery cell with a concentric tab design, in accordance with some example embodiments;

[0034] FIG. 2E depicts another horizontal cross sectional view of another example of a battery cell with a concentric tab design, in accordance with some example embodiments;

[0035] FIG. 3A depicts a schematic diagram illustrating the direction of current flow and electron flow in an example of a battery cell with a concentric tab design, in accordance with some example embodiments;

[0036] FIG. 3B depicts a schematic diagram illustrating the direction of current flow and electron flow in another example of a battery cell with a concentric tab design, in accordance with some example embodiments;

[0037] FIG. 4A depicts a schematic diagram illustrating the horizontal cross sectional view of an example of a battery cell with a concentric tab design, in accordance with some example embodiments;

[0038] FIG. 4B depicts a schematic diagram illustrating the horizontal cross sectional view of another example of a battery cell with a concentric tab design, in accordance with some example embodiments;

[0039] FIG. 4C depicts a schematic diagram illustrating the horizontal cross sectional view of another example of a battery cell with a concentric tab design, in accordance with some example embodiments;

[0040] FIG. 4D depicts a schematic diagram illustrating the horizontal cross sectional view of another example of a battery cell with a concentric tab design, in accordance with some example embodiments;

[0041] FIG. 4E depicts a schematic diagram illustrating the horizontal cross sectional view of another example of a battery cell with a concentric tab design, in accordance with some example embodiments;

[0042] FIG. 5A depicts a schematic diagram illustrating the horizontal cross sectional view of an example of a battery cell with multiple shafts for current collection and temperature regulation, in accordance with some example embodiments;

[0043] FIG. 5B depicts a schematic diagram illustrating the horizontal cross sectional view of another example of a battery cell with multiple shafts for current collection and temperature regulation, in accordance with some example embodiments;

[0044] FIG. 5C depicts a schematic diagram illustrating the horizontal cross sectional view of another example of a battery cell with multiple shafts for current collection and temperature regulation, in accordance with some example embodiments;

[0045] FIG. 5D depicts a schematic diagram illustrating the horizontal cross sectional view of another example of a battery cell with multiple shafts for current collection and temperature regulation, in accordance with some example embodiments;

[0046] FIG. 5E depicts a schematic diagram illustrating the horizontal cross sectional view of another example of a battery cell with multiple shafts for current collection and temperature regulation, in accordance with some example embodiments;

[0047] FIG. 5F depicts a schematic diagram illustrating the horizontal cross sectional view of another example of a battery cell with multiple shafts for current collection and temperature regulation, in accordance with some example embodiments; and

[0048] FIG. 6 depicts a table illustrating a comparison of various performance metrics for a battery cell with a concentric tab design and a battery cell with a conventional tab design, in accordance with some example embodiments.

[0049] When practical, similar reference numbers denote similar structures, features, or elements.DETAILED DESCRIPTION

[0050] During the charging and discharging of a battery cell, electrons (or electric charge or current) flows into and out of the battery cell through the electrode tabs coupled with the positive electrode (or cathode) and negative electrode (or anode). In this context, each "electrode tab" is a metallic strip the battery cell that is electrically coupled with the current collector (e.g., metal foil) of the corresponding electrode. While the battery cell is being discharged, electrons flow from the negative electrode (or anode) to the positive electrode (or cathode) via the positive electrode tab coupled with the positive electrode (or cathode) and the negative electrode tab coupled with the negative electrode (or anode). During the charging of the battery cell, the flow of electrons (or electric charge or current) is reversed. That is, electrons flow from the positive electrode (or cathode) back to the negative electrode (or anode), also via the positive electrode tab coupled with the positive electrode (or cathode) and the negative electrode tab coupled with the negative electrode (or anode). Depending on the direction of electric current flow, the electrode tab electrically coupled with a current collector (e.g., metal foil) may collect electric current from the current collector or, alternatively, distribute electric current thereto.

[0051] Given their role in distributing electric current (or electrons) to and from the current collectors coupled therewith, electrode tabs are a critical component of any battery cell.The design of electrode tabs play a deterministic role in the performance of a battery cell. Forexample, design elements, such as the material, quantity, layout (or placement), and cross- sectional area of electrode tabs, may significantly impact the charge rate of a battery cell by influencing cell impedance, current distribution, and temperature regulation. For example, higher charge rates may be achieved using higher conductivity electrode tabs (e.g., nickel (Ni) plated copper (Cu) electrode tabs), more or larger sized electrode tabs may lower overall cell impedance, and electrode tab layout may be optimized to shorten the travel paths of electrons (or electric current) within current collectors. In some cases, increasing the quantity and / or size of electrode tabs may reduce overall cell impedance, thus facilitating the flow of higher electric current during the charging and discharging of the battery cell. The quantity, size, and placement of electrode tabs also influence the distribution of electric current (or electrons) through the current collector (and the electrode coupled therewith), which in turn affects the uniformity of the charging process and heat dissipation. Finally, the rate capability of a battery cell may be further improved by shortening the distance electrons travel within current collectors (e.g., the effective electrode length) through optimal placement of electrode tabs.

[0052] Electrode tabs are typically electrically coupled to portions of the current collector that have not been coated with an electrode active material. For example, an electrode tab may be welded to the uncoated, tab area portion of a current collector, which typically extend out from another portion of the current collector that has been coated with the electrode active material. In some cases, the electrode tab is also electrically coupled with the terminal (e.g., negative terminal or positive terminal) of the battery cell. With conventional designs, the tab areas of a current collector (and the electrode tabs coupled therewith) are placed on one side of the current collector. For example, the example of the battery cell 100 shown in FIG. 1 A includes a tab 110 placed on one side of the first current collector 111 coupled with the first electrode 113 and another tab 110 placed on one side of the second current collector 115 coupled with the second electrode 117. The example of the battery cell 100 shown in FIG. IBhas a multi -tab (or all-tab) design in which multiple tabs 110 are placed on one side of the first current collector 111 coupled with the first electrode 113 and multiple tabs 110 are placed on one side of the second current collector 115 coupled with the second electrode 117. While the multi -tab (or all tab) design of the battery cell 100 shown in FIG. IB exhibits better power capability than the single tab design of the battery cell 100 shown in FIG. 1A, these conventional electrode tab designs still have limited rate capabilities when deployed in larger sized battery cells. The limitations in charge rate arise when the distance electrons travel within current collectors (e.g., the first current collector 111, the second current collector 115) increases with the size of the battery cell. Furthermore, when the size of the battery cell increases, heat distribution also becomes less uniform with conventional electrode tab designs. This is because in a larger sized battery cell, the heat generated at the center of the electrodes must be travel a longer distance before reaching an external heat exchange source and vice versa (cooling or heating). The non-uniformity in heat distribution may result in nonuniformity in material expansion, non-uniformity in ion distribution, as well as non-uniformity in the charging or discharging states of the electrode.

[0053] For some battery cell formats, the only external heat exchange source may be the case of the battery cell, which is typically electrically coupled to either the negative electrode or the positive electrode of the battery cell. In instances where the case of the battery cell is connected to the negative electrode but not the positive electrode, the heat generated by the positive electrode at the center of the battery cell must travel through electrolyte, multiple layers of electrodes, and separator before reaching the case. Alternatively, the heat generated by the positive electrode at the center of the battery cell must first travel horizontally through the electrolyte and the separator before vertically through the negative electrodes to reach the end of the case. These heat distribution patterns engender significant top-center-bottomtemperature non-uniformities, which in turn create internal stress within the electrodes, negatively impact electrical performance, and accelerates cell aging and degradation.

[0054] Various example embodiments of the present disclosure include a concentric tab design that improves upon the deficiencies of conventional electrode tab designs. For example, in some cases, the concentric tab design may include a central tab formed by a layer of electrode active material that coats a surface of a current collector (e.g., metal foil) while leaving an inner perimeter of the current collector exposed. That is, the central tab may be formed from a gap between the outer edge of the current collector and outer edge of the layer of electrode active material in which the layer of electrode active material does not coat, cover, or otherwise conceal the surfaces of the current collector. In some cases, the central tab may be secured (e.g., welded, soldered, and / or the like), for example, by an electrically conductive connection, to one or more shafts disposed in an orthogonal orientation relative to the current collector. In some cases, the concentric tab design may further include a peripheral tab formed by a layer of electrode active material that coats a surface of another current collector (e.g., metal foil) while leaving an outer perimeter of the other current collector exposed. That is, the peripheral tab may be formed from a gap between the inner edge of the current collector and inner edge of the layer of electrode active material in which the layer of electrode active material does not coat, cover, or otherwise conceal the surfaces of the current collector. In some cases, the peripheral tab may be secured (e.g., welded, soldered, and / or the like), for example, by an electrically conductive connection, to a battery case. In some cases, a battery cell incorporating a concentric tab design may exhibit lower cell impedance and higher power density than a battery cell with conventional tab designs (e.g., the single tab design shown in FIG. 1A and the multi-tab (or all-tab) design shown in FIG. IB). This is because various example embodiments of the concentric tab design described herein provide more symmetrical current flow and shorter current (or electron) flow distance than conventional tab designs.Accordingly, a battery cell incorporating various example embodiments of the concentric tab design described herein may exhibit a higher charge rate and discharge rate (or faster charging and discharging) with better thermal management for greater operational safety and longevity.

[0055] In some example embodiments, a battery cell may include a first current collector (e.g., a first metal foil) coupled with a first electrode, a second current collector (e.g., a second metal foil) coupled with a second electrode having an opposite polarity as the first electrode, and a separator interposed between the first electrode and the second electrode. In some cases, the first electrode includes a first layer of electrode active material disposed on a surface of the first current collector while the second electrode includes second layer of electrode active material disposed on a surface of the second current collector. In some cases, the first layer of electrode active material and the first current collector may be concentric (e.g., sharing a common center point) with the dimensions of the first layer of electrode active material being smaller than that of the first current collector such that an outer perimeter of the first current collector is exposed and not coated with electrode active material. In some cases, the exposed outer perimeter of the first current collector may form a peripheral electrode tab secured (e.g. welded, soldered, and / or the like), with an electrically conductive connection, to the case of the battery cell. In some cases, the second layer of electrode active material and the second current collector may be concentric (e.g., sharing a common center point) with the dimensions of the second layer of electrode active material being smaller than that of the second current collector such that an inner perimeter of the second current collector is exposed and not coated with electrode active material. In some cases, the exposed inner perimeter of the second current collector may form a central electrode tab secured (e.g., welded, soldered, and / or the like), with an electrically conductive connection, to one or more shafts disposed at a center of the battery cell. In some cases, the one or more shafts may be placed orthogonal in orientation to that of the first current collector, the first electrode, the separator, the second currentcollector, and the second electrode. In some cases, the one or more shafts may be solid bar of a thermally conductive material (e.g., aluminum (Al), copper (Cu), and / or the like) serving as a heat sink that absorbs and dissipates heat generated by the electrodes. Alternatively, the one or more shafts may be a hollow tube filled with a coolant (e.g., a solid coolant, a liquid coolant, a gas coolant, and / or the like) for regulating the temperature of the battery cell during operation.

[0056] FIG. 2A depicts a horizonal cross sectional view of an example of a battery cell 200 with a concentric tab design, in accordance with some example embodiments. A transparent perspective view of an example of the battery cell 200 in a cylindrical cell format is depicted in FIG. 2B while a transparent perspective view of an example of the battery cell 200 in a prismatic (or pouch) cell format is depicted in FIG. 2C. Vertical cross sectional views of the battery cell 200 are shown in FIGS. 2D-E. It should be appreciated that the battery cell 200 may be in a different format than the examples shown in FIGS. 2A-E. Moreover, the battery cell 200 may be in any battery chemistry including, for example, metal ion (e.g., lithium (ion), sodium (Na) ion), solid state, and / or the like.

[0057] Referring to FIGS. 2A-E, the battery cell 200 may include a first electrode 205a in which one or more layers of a first electrode active material 201a are coupled with a first current collector 202a. For example, in some cases, the first electrode active material 201a may be coated on one surface of the first current collector 202a. In some cases, the first electrode active material 201a may also be coated on an opposite surface of the first current collector 202a. In the example shown in FIGS. 2A-E, the first current collector 202a may be a metal foil interposed between two layers of the first electrode active material 201a. That is, in the example shown in FIG. 2A, the first electrode active material is coated on opposite surfaces of the first current collector 202a. In some cases, the battery cell 200 may further include a second electrode 205b having an opposite polarity as the first electrode 205a. In some cases, the second electrode 205b may include one or more layers of a second electrode active material201b coupled with a second current collector 202b. For instance, in some cases, the second electrode active material 201b may be coated on one or both surfaces of the second current collector 202b. In the example shown in FIG. 2 A, the second current collector 202b may be a metal foil interposed between two layers of the second electrode active material 201b. In some cases, the concentric tab design of the battery cell 200 stacks concentric layers of the first electrode active material 201a, the first current collector 202a, the second electrode active material 201b, the second current collector 202b, and the separator 203 whereas conventional battery designs requires winding or folding layers of the first electrode active material 201a, the first current collector 202a, the second electrode active material 201b, the second current collector 202b, and the separator 203 into a jellyroll. That the layers of the first electrode active material 201a, the second electrode active material 201b, and the separator 203 are stacked rather than wound (or folded) may enable the use of thicker layers of the first electrode active material 201a and the second electrode active material 201b. In some cases, the thicker layers of the first electrode active material 201a and the second electrode active material 201b may increase the energy density of the battery cell 200.

[0058] In some cases, the battery cell 200 may include one or more electrolytes (e.g., formed from one or more ionically conducive materials) including, for example, a liquid electrolyte, a solid electrolyte, a gel electrolyte, and / or the like. In some cases, the concentric tab design of the battery cell 200, including the stacking of concentric layers of the first electrode active material 201a, the first current collector 202a, the second electrode active material 201b, the second current collector 202b, and the separator 203, may enable the use of a solid-state-electrolyte. In some cases, the solid-state-electrolyte may also act as the separator 203. In some cases, the use of more rigid materials (e.g., ceramic and / or the like) for the separator 203. It should be appreciated that increasing the rigidity of the separator 203 improves the safety profile of the battery cell 200.

[0059] In the example shown in FIGS. 2A-E, the second current collector 202b may be a metal foil interposed between two layers of the second electrode active material 201b. In some cases, a first layer of a separator 203 (e.g., formed from one or more porous electrically nonconductive materials) may be interposed between the first electrode 205a and the second electrode 205b (e.g., between a layer of the first electrode active material 201a forming the first electrode 205a and a layer of the second electrode active material 201b forming the second electrode 205b). In some cases, the battery cell 200 may include one or more additional electrodes. For example, as shown in FIG. 2A, the battery cell 200 may include a third electrode 205c having a same polarity as the first electrode 205a and an opposite polarity as the second electrode 205b. In some cases, the third electrode 205c may also include the first current collector 202a interposed between two layers of the first electrode active material 201a. In some cases, the battery cell 200 may also include a fourth electrode 205d having an opposite polarity as the third electrode 205c. In some cases, the fourth electrode 205d may include the second current collector 202b interposed between two layers of the second electrode active material 201b. As shown in FIG. 2A, a second layer of the separator 203 may be interposed between the second electrode 205b and the third electrode 205c while a third layer of the separator 203 may be interposed between the third electrode 205c and the fourth electrode 205d.

[0060] Referring again to FIGS. 2A-E, in some cases, the battery cell 200 may be configured with a concentric tab design formed by stacking concentric layers of the first electrode active material 201a, the first current collector 202a, the separator 203, the second electrode active material 201b, and the second current collector 202b. As shown in FIGS. 2A-E, the concentric layers of the first electrode active material 201a, the first current collector 202a, the separator 203, the second electrode active material 201b, and the second current collector 202b may share a common center point in the form of a shaft 210. In the example ofthe battery cell 200 shown in FIGS. 2A-E, the shaft 210 may be oriented along a first axis (e.g., y-axis) that is orthogonal to the plane (e.g., xz-plane) occupied by the concentric layers of the first electrode active material 201a, the first current collector 202a, the separator 203, the second electrode active material 201b, and the second current collector 202b. In some cases, the shaft 210 may be electrically insulated from the case 220 of the battery cell 200. In some cases, the shaft 210 may be a solid bar.

[0061] In some example embodiments, the battery cell 200 may include one or more thermal regulation mechanisms. For example, in instances where the shaft 210 is a solid bar, the shaft 210 may be formed from one or more thermally conductive materials (e.g., aluminum (Al), copper (Cu), and / or the like) such that the shaft 210 serves as a heat sink. Alternatively, the shaft 210 may be a hollow tube filled with a coolant 215 for regulating the temperature of the battery cell 200 during operation. In some cases, the coolant 215 may be one or more of a solid coolant, a liquid coolant, or a gas coolant. In some cases, the shaft 210 may serve as a thermal regulator for absorbing and dissipating heat generated by the one or more layers of the second electrode active material 201b forming the second electrode 205b and / or the fourth electrode 205d. In some cases, the one or more thermal regulation mechanism may also include the case 220 of the battery cell 200. For instance, in some cases, the case 220 of the battery cell 200 may be formed from one or more thermally conductive materials (e.g., aluminum (Al), copper (Cu), and / or the like) such that the case 220 may also serve as a heat sink. In some cases, the case 220 may absorb and dissipate heat generated by the one or more layers of the first electrode active material 210a forming the first electrode 205a and / or the third electrode 205c.

[0062] the first electrode 205a, the second electrode 205b, the third electrode 205c, the fourth electrode 205d, and / or the like

[0063] In some example embodiments, the battery cell 200 may include one or more features to facilitate the assembly of the concentric tab design. For example, in some cases, an exterior surface of the shaft 210 and / or an interior surface of the case 220 may be slotted (e.g., includes one or more slots) to facilitate the placement and securing (e.g., welding, soldering, and / or the like) of the concentric layers of the first electrode active material 201a, the first current collector 202a, the separator 203, the second electrode active material 201b, and the second current collector 202b. In some cases, the one or more slots in the shaft 210 and / or the case 220 may be sealed once the concentric layers of the first electrode active material 201a, the first current collector 202a, the separator 203, the second electrode active material 201b, and the second current collector 202b have been secured (e.g., welded, soldered, and / or the like) thereto.

[0064] In some example embodiments, at least one dimension (e.g., diameter, radius, length, width, and / or the like) of the concentric layers of the first electrode active material 201a, the first current collector 202a, the separator 203, the second electrode active material 201b, and the second current collector 202b may be configured to enable an exposed inner perimeter 206 of the first current collector 202a to form a central tab 207 contacting the shaft 210. For example, in some cases, at least one dimension (e.g., diameter, radius, length, width, and / or the like) of the one or more layers of the first electrode active material 201a disposed on opposite surfaces of the first current collector 202a may be smaller than a corresponding dimension (e.g., diameter, radius, length, width, and / or the like) of the first current collector 202a, thus leaving both surfaces of the inner perimeter 206 of the first current collector 202a exposed (e.g., not coated with the first electrode active material 201a). In some cases, the exposed inner perimeter 206 of the first current collector 202a may be a gap between the inner edge of the first current collector 202a and the inner edge of the one or more layers of the first electrode active material201a where the surfaces of the first current collector 202a are not covered, coated, or otherwiseconcealed by the one or more layers of the first electrode active material 201a. In some cases, the exposed inner perimeter 206 of the first current collector 202a may form the central tab 207, which may be secured (e.g., welded, soldered, and / or the like) to the shaft 210. In some cases, the dimensions of the first current collector 202a may be smaller than that of the case 220, such that the outer perimeter of the first current collector 202a does not contact the case 220 of the battery cell 200 while the inner perimeter 206 of the first current collector 202a is in contact with the shaft 210.

[0065] In some example embodiments, at least one dimension (e.g., diameter, radius, length, width, and / or the like) of the concentric layers of the first electrode active material 201a, the first current collector 202a, the separator 203, the second electrode active material 201b, and the second current collector 202b may be configured to enable an exposed outer perimeter 208 of the second current collector 202b to form a peripheral tab 209 contacting the case 220 of the battery cell 200. For example, in some cases, at least one dimension (e.g., diameter, radius, length, width, and / or the like) of the one or more layers of the second electrode active material 201b disposed on opposite surfaces of the second current collector 202b may be smaller than a corresponding dimension (e.g., diameter, radius, length, width, and / or the like) of the second current collector 202b, thus leaving both surfaces of the outer perimeter 208 of the second current collector 202b exposed. In some cases, the exposed outer perimeter 208 of the second current collector 202b may be a gap between the outer edge of the second current collector 202b and the outer edge of the one or more layers of the second electrode active material 201b where the surfaces of the second current collector 202b are not coated, covered, or otherwise concealed by the one or more layers of the second electrode active material 201b. In some cases, the exposed outer perimeter 208 of the second current collector 202b may form the peripheral tab 209, which may be secured (e.g., welded, soldered, and / or the like) to the case 220 of the battery cell 200. In some cases, the dimensions of the second current collector202b may be smaller than that of the case 220, such that the inner perimeter of the second current collector 202b does not contact the shaft 110 while the outer perimeter 208 of the second current collector 202b is in contact with the case 220 of the battery cell 200.

[0066] In some example embodiments, the concentric tab design of the battery cell 200 may reduce impedance within the battery cell 200 while increasing its power density. These improvements in the performance of the battery cell 200 may be attributed to the concentric tab design increasing the symmetry of current flow and reducing the distance electrons (or electric current) travel within the first current collector 202a and the second current collector 202b (e.g., the effective electrode length). The aforementioned improvements are depicted schematically in FIG. 3 A in the horizontal cross section of a cylindrical cell and in FIG. 3B in the horizontal cross section of a prismatic (or pouch) cell. The arrows indicate the direction of current flow, which is opposite to the direction of the flow of electrons. As shown in FIGS. 3A-B, current flow is more symmetrical in both the first current collector 202a of the first electrode 205a and the second current collector 202b of the second current collector 205b. More symmetrical current flow may in turn increase the charge (and discharge) rate of the battery cell 200 at least because electrons (or electric current) travel a shorter distance into and out of the battery cell 200. Furthermore, more symmetrical current flow and shorter electron (or electric current) travel distance may improve heat distribution across the battery cell 200. In some cases, heat generated by the first electrode 205a and the second electrode 205b may be further dissipated by the shaft 110 and the case 220 of the battery cell 200.

[0067] FIGS. 4A-E depict schematic diagrams illustrating the horizontal cross sectional view of additional examples of the battery cell 200 with different horizontal cross-section shapes, in accordance with some example embodiments. For example, as shown in FIGS. 4A- E, the horizontal cross section of the battery cell 200 may be a triangle (FIG. 4A), a rectangle (FIG. 4B), a pentagon (FIG. 4C), a hexagon (FIG. 4D), a blade (FIG. 4E), and / or the like.Moreover, in some cases, the horizontal cross sectional shape of the shaft 210 may correspond to that of the battery cell 200. For instance, the horizontal cross section of the shaft 210 may be a triangle (FIG. 4A), a rectangle (FIG. 4B), a pentagon (FIG. 4C), a hexagon (FIG. 4D), a blade (FIG. 4E), and / or the like. However, it should be appreciated that the horizontal cross section of the shaft 210 does not necessarily have to have a same shape as the horizontal cross section of the battery cell 200.

[0068] In some example embodiments, instead of the single shaft 210 shown in FIGS. 2A-E, 3A-B, and 4A-E, the battery cell 200 may include multiple shafts having a same (or different) horizontal cross section shape as the battery cell 200. FIGS. 5A-F depict illustrating the horizontal cross sectional view of additional examples of the battery cell 200 with multiple shafts for current collection and temperature regulation, in accordance with some example embodiments. In some cases, additional shafts may be included in the battery cell 200 when the dimensions of the battery cell 200 increases and a single shaft is insufficient for current collection and temperature regulation (e.g., heat distribution and dissipation). In some cases, the quantity of shafts included in the battery cell 200 may be proportional to one or more dimensions of the battery cell 200, such as an area of a cross section parallel to a plane of the separator 203, the first electrode 205a, the second electrode 205b, and / or the like (e.g., horizontal cross sectional area of the battery cell 200). For example, FIG. 5A depicts an example of the battery cell 200 having a circular horizontal cross section and five shafts that also have a circular horizontal cross section. The example of the battery cell 200 in FIG. 5B has a triangular horizontal cross section and four shafts also with a triangular horizontal cross section. In FIG. 5C, the horizontal cross section of the battery cell 200 is a square in shape while the horizontal cross sections of the five shafts included in the battery cell 200 are also square in shape. The example of the battery cell 200 in FIG. 5D has a rectangular horizontal cross section and three shafts with the same rectangular horizontal cross section. FIGS. 5E-Fdepicts examples of the battery cell 200 whose horizontal cross sections are polygons in shape (e.g., pentagon in FIG. 5E and hexagon in FIG. 5F). In those examples, the horizontal cross sections of the constituent shafts (e.g., six in FIG. 5E and seven in FIG. 5F) are the same polygons in shape (e.g., pentagons in FIG. 5E and hexagons in FIG. 5F).

[0069] As noted, various example embodiments of the concentric tab design described herein may improve the charge and discharge rate as well as the temperature regulation of battery cells. These improvements are evidenced in a test cell constructed with a concentric tab design. The test cell included layers of a positive electrode active material with an areal loading of 20 milligrams per square centimeter over an area of 596 square centimeters. The test cell further included layers of a negative electrode active material with an areal loading of 10.8 milligrams per square centimeter over an area of 608.8 square centimeters. Table 600 in FIG. 6 compares the impedance, voltage, charge time, discharge capacity retention, and peak temperature of the test cell and a baseline cell having a conventional tab design. As the performance metrics in Table 600 show, the test cell with the concentric tab design exhibits much lower impedance, in this case, it is 26.9% lower than the baseline cell with the conventional tab design when the cells are fresh and 25% lower post formation. The charge time of the test cell with the concentric tab design is approximately 15 minutes faster than the charge time of the baseline cell with the conventional tab design at 0.3C constant current constant voltage (CCCV) charging protocol. The discharge capacity retention of the test cell with the concentric tab design is 3.7% higher than the baseline cell with the conventional tab design. The test cell with the concentric tab design also exhibits a lower peak temperature than the baseline cell with the conventional tab design traditional. For the single-layer design of the test cell, the difference in peak temperature was 0.9°C. It should be appreciated that the benefit of the concentric tab design in temperature regulation would be more significant in a multilayer design.

[0070] In the descriptions above and in the claims, phrases such as “at least one of’ or “one or more of’ may occur followed by a conjunctive list of elements or features. The term “and / or” may also occur in a list of two or more elements or features. Unless otherwise implicitly or explicitly contradicted by the context in which it used, such a phrase is intended to mean any of the listed elements or features individually or any of the recited elements or features in combination with any of the other recited elements or features. For example, the phrases “at least one of A and B;” “one or more of A and B;” and “A and / or B” are each intended to mean “A alone, B alone, or A and B together.” A similar interpretation is also intended for lists including three or more items. For example, the phrases “at least one of A, B, and C;” “one or more of A, B, and C;” and “A, B, and / or C” are each intended to mean “A alone, B alone, C alone, A and B together, A and C together, B and C together, or A and B and C together.” Use of the term “based on,” above and in the claims is intended to mean, “based at least in part on,” such that an unrecited feature or element is also permissible.

[0071] The subject matter described herein can be embodied in systems, apparatus, methods, and / or articles depending on the desired configuration. The implementations set forth in the foregoing description do not represent all implementations consistent with the subject matter described herein. Instead, they are merely some examples consistent with aspects related to the described subject matter. Although a few variations have been described in detail above, other modifications or additions are possible. In particular, further features and / or variations can be provided in addition to those set forth herein. For example, the implementations described above can be directed to various combinations and subcombinations of the disclosed features and / or combinations and subcombinations of several further features disclosed above. In addition, the logic flows depicted in the accompanying figures and / or described herein do not necessarily require the particular order shown, orsequential order, to achieve desirable results. Other implementations may be within the scope of the following claims.

Claims

CLAIMSWhat is claimed is:

1. A battery cell, comprising: a case enclosing a shaft, a first electrode, a second electrode having an opposite polarity as the first electrode, and a first separator interposed between the first electrode and the second electrode, wherein the shaft is disposed in an orthogonal orientation relative to a plane of the first electrode, the second electrode, and the first separator, the first electrode includes one or more layers of a first electrode active material disposed on one or more surfaces of a first current collector, the one or more layers of the first electrode active material having at least one dimension that is smaller than a corresponding dimension of the first current collector such that an outer perimeter of the first current collector is exposed, and an exposed outer perimeter of the first current collector forming a peripheral tab in electrical contact with the case of the battery cell, and the second electrode includes one or more layers of a second electrode active material disposed on one or more surfaces of a second current collector, the one or more layers of the second electrode active material having at least one dimension that is smaller than a corresponding dimension of the second current collector such that an inner perimeter of the second current collector is exposed, and an exposed inner perimeter of the second current collector forming a central tab in electrical contact with the shaft.

2. The battery cell of claim 1, wherein at least one of the shaft and the case of the battery cell comprises a heat sink that absorbs and dissipates heat generated by the electrodes.

3. The battery cell of any of claims 1 to 2, wherein the shaft comprises a hollow tube filled by one or more coolants.

4. The battery cell of claim 3, wherein the one or more coolants include a gas coolant, a liquid coolant, and / or a solid coolant.

5. The battery cell of any of claims 1 to 4, wherein the shaft comprise a solid bar formed from one or more thermally conductive materials.

6. The battery cell of any of claims 1 to 5, wherein the perimeter tab is secured to the case of the battery cell by welding or soldering.

7. The battery cell of any of claims 1 to 6, wherein the central tab is secured to the shaft by welding or soldering.

8. The battery cell of any of claims 1 to 7, wherein an outer surface of the shaft includes one or more slots for receiving one or more central tabs.

9. The battery cell of any of claims 1 to 8, wherein an inner surface of the case includes one or more slots for receiving one or more peripheral tabs.

10. The battery cell of any of claims 1 to 9, further comprising: one or more additional shafts disposed in the orthogonal orientation relative to a plane of the first electrode, the second electrode, and the first separator.

11. The battery cell of any of claims 1 to 10, wherein the battery cell includes a quantity of shafts proportional to one or more dimensions of the battery cell.

12. The battery cell of claim 11, wherein the quantity of shafts is proportional to an area of a cross section parallel to the plane of the first electrode, the second electrode, and the first separator.

13. The battery cell of any of claims 1 to 12, wherein the battery cell include one, two, three, four, five, six, or seven shafts.

14. The battery cell of any of claims 1 to 13, wherein the case further encloses a third electrode having a same polarity as the first electrode but an opposite polarity as the second electrode, wherein the third electrode includes one or more layers of the first electrode active material disposed on one or more surfaces of a third current collector, wherein the one or more layers of the first electrode active material have at least one dimension that is smaller than a corresponding dimension of the third current collector such that an outer perimeter of the third current collector is exposed, and wherein an exposed outer perimeter of the third current collector forms an additional peripheral tab in electrical contact with the case of the battery cell.

15. The battery cell of claim 14, wherein the case further encloses a fourth electrode having an opposite polarity as the third electrode, wherein the fourth electrode includes one or more layers of the second electrode active material disposed on one or more surfaces of a fourth current collector, wherein the one or more layers of the second electrode active material have at least one dimension that is smaller than a corresponding dimension of the fourth current collector such that an inner perimeter of the fourth current collector is exposed, and wherein an exposed inner perimeter of the fourth current collector forms an additional central tab in electrical contact with the shaft of the battery cell.

16. The battery cell of any of claims 1 to 15, wherein the one or more layers of the first electrode active material, the first current collector, the one or more layers of the secondelectrode active material, the second current collector, and the first separator comprise a plurality of concentric layers.

17. The battery cell of claim 16, wherein the plurality of concentric layers share a common axis comprising the shaft.

18. The battery cell of any of claims 1 to 17, wherein the separator comprises a rigid separator.

19. The battery cell of any of claims 1 to 18, wherein the separator comprises a ceramic-based separator.

20. The battery cell of any of claims 1 to 19, wherein the separator comprises a solid state electrolyte.

21. The battery cell of any of claims 1 to 20, wherein the case further encloses one or more of a liquid electrolyte, a gel electrolyte, and a solid electrolyte.

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