Electrode assembly, secondary battery, and manufacturing method

Abstract

To provide a device for electrical conduction.SOLUTION: A device includes a unit cell 500 having a plurality of components, including an electrode separated from a counter electrode by a separator 130, stacked along a first axis of the separator, and the side of the separator faces an electrode active material 125 coupled with a plurality of spacer structures 400 to create a space between the separator and the electrode active material, the space is disposed away from the periphery of the separator along a second axis perpendicular to the first axis, the space exists between the electrode active material and the separator during a first use of the device, and the electrode active material extends into the space during a second use of the device.SELECTED DRAWING: Figure 3B

Description

[Technical Field]

[0001] The present disclosure relates generally to methods of manufacturing electrode assemblies for use in energy storage devices, and to energy storage devices including electrode assemblies manufactured according to the methods herein. [Background technology]

[0002] A rocking-chair or insertion-type secondary battery is a type of energy storage device in which carrier ions, such as lithium, sodium, potassium, calcium, or magnesium ions, move between a positive electrode and a negative electrode through an electrolyte. A secondary battery can include a single battery cell or two or more battery cells electrically coupled to form a battery, each battery cell including a positive electrode, a negative electrode, a microporous separator, and an electrolyte.

[0003] In a rocking chair battery cell, both the positive and negative electrodes contain materials that insert and extract carrier ions. When the cell is discharged, carrier ions are extracted from the negative electrode and inserted into the positive electrode. When the cell is charged, the reverse process occurs, and carrier ions are extracted from the positive electrode and inserted into the negative electrode. Summary of the Invention [Problem to be solved by the invention]

[0004] When carrier ions move between electrodes, one persistent challenge lies in the fact that the electrodes tend to expand and contract as the battery is repeatedly charged and discharged. Swelling and contraction during cycling tends to be problematic for battery reliability and cycle life, as electrode expansion can lead to electrical shorts and battery failure. Yet another problem that can arise is that misalignment of the electrodes, due to physical or mechanical stress on the battery during manufacture, use, or shipping, can lead to battery shorts and failure.

[0005] Therefore, there remains a need to control the expansion and contraction of electrodes during battery cycling to improve battery reliability and cycle life. Furthermore, there remains a need for reliable and effective means for manufacturing such batteries. That is, there is a need for an efficient manufacturing method for providing batteries including electrode assemblies in which the expansion of the electrode assembly during battery cycling is controlled. [Means for solving the problem]

[0006] Briefly, one aspect of the present disclosure relates to a secondary battery that cycles between a charged state and a discharged state. The secondary battery includes a battery casing, an electrode assembly, carrier ions, and a nonaqueous electrolyte solution within the battery casing. In this secondary battery, the electrode assembly includes a group of unit cells, and each unit cell includes, in a stacked sequence, a unit cell portion of an electrode current collector layer, an electrode layer including an electrode active material, a separator layer, a counter electrode layer, and a unit cell portion of a counter electrode current collector layer. The unit cell has a width W measured in the stacking direction of the stacked sequence from the unit cell portion of the electrode current collector to the unit cell portion of the counter electrode current collector. uc The electrode layer has a width W measured in the stacking direction of the stacked continuum from the unit cell portion of the electrode current collector adjacent to this electrode layer to the separator layer adjacent to the electrode layer. E , a height H measured from the top surface to the bottom surface of the electrode layer in a second direction perpendicular to the stacking direction E , and a length L measured from the first surface to the second surface in a third direction perpendicular to the stacking direction and the height direction. E , and a volume V bounded by the unit cell portion of the electrode current collector, the separator layer, the top surface of the electrode layer, the bottom surface of the electrode layer, the first end surface of the electrode layer, and the second end surface of the electrode layer. E The electrode layer includes a population of spacer structures that include a material other than the electrode active material, and (a) the spacer population has a volume V of the electrode layer. E (b) a member of the spacer group is located within each sub-volume of the electrode layer, and the electrode layer (i) occupies a total volume within the electrode layer within a range of about 0.1% to about 35% of the volume V of the electrode layer; Eand (ii) is bounded on all sides by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0007] Another aspect of the present disclosure relates to an electrode assembly for a secondary battery that cycles between a charged state and a discharged state. The electrode assembly includes a group of unit cells, and each unit cell includes, in a stacked sequence, a unit cell portion of an electrode current collector layer, an electrode layer containing an electrode active material, a separator layer, a counter electrode layer, and a unit cell portion of a counter electrode current collector layer. The unit cell has a width W measured in the stacking direction of the stacked sequence from the unit cell portion of the electrode current collector to the unit cell portion of the counter electrode current collector. uc The electrode layer has a width W measured in the stacking direction from a unit cell portion of the electrode current collector adjacent to the electrode layer to a separator layer adjacent to the electrode layer. e a height He measured from the top surface to the bottom surface of the electrode layer in a second direction perpendicular to the stacking direction, a length Le measured from the first surface to the second surface in a third direction perpendicular to the stacking direction and the height direction, and a volume V bounded by the unit cell portion of the electrode current collector, the separator layer, the top surface of the electrode layer, the bottom surface of the electrode layer, the first end surface of the electrode layer, and the second end surface of the electrode layer. E The electrode layer includes a population of spacer structures, and (a) the spacer population has a volume V of the electrode layer. E (b) a member of the spacer group is located within each sub-volume of the electrode layer, and the electrode layer (i) occupies a total volume within the electrode layer within a range of about 0.1% to about 35% of the volume V of the electrode layer; E and (ii) is bounded on all sides by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0008] Yet another aspect of the present disclosure relates to a method for forming a secondary battery that cycles between a charged state and a discharged state, the method for forming the secondary battery comprising providing an electrode assembly, carrier ions, and a non-aqueous electrolyte solution in a battery case, the electrode assembly comprising a group of unit cells, each unit cell comprising, in a stacked sequence, a unit cell portion of an electrode current collector layer, an electrode layer including an electrode active material, a separator layer, a counter electrode layer, and a unit cell portion of a counter electrode current collector layer, the unit cell having a width W measured in the stacking direction of the stacked sequence from the unit cell portion of the electrode current collector to the unit cell portion of the counter electrode current collector. uc The electrode layer has a width W measured in the stacking direction from a unit cell portion of the electrode current collector adjacent to the electrode layer to a separator layer adjacent to the electrode layer. e , the height H measured from the top surface to the bottom surface of the electrode layer in a direction perpendicular to the stacking direction E and a length Le measured from the first surface to the second surface in a direction perpendicular to the stacking direction and the height direction, and a volume Ve bounded by the unit cell portion of the electrode current collector, the separator layer, the top surface of the electrode layer, the bottom surface of the electrode layer, the first end surface of the electrode layer, and the second end surface of the electrode layer. The electrode layer includes a group of spacer structures, where (a) the spacer group occupies a total volume within the electrode layer that is within a range of about 0.1% to about 35% of the volume Ve of the electrode layer, and (b) members of the spacer group are located within each sub-volume of the electrode layer, and the electrode layer (i) has at least 25% of the volume Ve of the electrode layer and (ii) is bounded on all sides by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer. The method further includes performing a formation process that includes charging the secondary battery from a discharged state to a charged state.

[0009] Other aspects, features, and embodiments of the present disclosure will be in part discussed and in part apparent in the following description and drawings. [Brief explanation of the drawings]

[0010] [Figure 1A]FIG. 1 is a perspective view of an embodiment of a secondary battery including an electrode assembly. [Figure 1B] FIG. 1 is a perspective view of another embodiment of a secondary battery including an electrode assembly. [Figure 2A] 1A and 1B are perspective and cross-sectional views of a further embodiment of a secondary battery including an electrode assembly. [Figure 2B] 1A and 1B are perspective and cross-sectional views of a further embodiment of a secondary battery including an electrode assembly. [Figure 3A] FIG. 1 is an exploded plan view of one embodiment of a structure including an electrode structure, a counter electrode structure, and a separator layer for an electrode assembly. [Figure 3B] 3B is an exploded cross-sectional view of an embodiment of the electrode assembly structure of FIG. 3A. [Figure 3C] FIG. 4 is a cross-sectional view of an embodiment of the electrode assembly structure of FIGS. 3A and 3B in a stacked configuration, further including a constraint set. [Figure 4A] FIG. 2 is a cross-sectional view of one embodiment of a structure including an electrode current collector, an electrode layer, a separator layer, and a counter electrode current collector for an electrode assembly, taken along the YX plane. [Figure 4B] 4B is a cross-sectional view of an embodiment of the electrode assembly structure of FIG. 4A taken in the YZ plane. [Figure 4C] FIG. 10 is a cross-sectional view of another embodiment of a structure including an electrode current collector, an electrode layer, a separator layer, and a counter electrode current collector for an electrode assembly, with a population of spacer structures within the electrode layer, taken along the YZ plane. [Figure 5A] FIG. 10 is a cross-sectional view of another embodiment of a structure including an electrode current collector, an electrode layer, a separator layer, and a counter electrode current collector for an electrode assembly, the structure including a population of spacer structures within the electrode layer, taken along the YX plane. [Figure 5B] 5B is a cross-sectional view of an embodiment of a structure for the electrode assembly of FIG. 5A taken in the YX plane, at a post-formation stage following a formation process that increases the volume of electrode active material within the electrode layer. [Figure 5C] 5B is a cross-sectional view of an embodiment of a structure for the electrode assembly of FIG. 5A, taken in the YZ plane. [Figure 5D]FIG. 10 is a cross-sectional view of another embodiment of a structure including an electrode current collector, an electrode layer, a separator layer, and a counter electrode current collector for an electrode assembly, the structure including a population of spacer structures within the electrode layer, taken along the YX plane. [Figure 6] FIG. 10 is a cross-sectional view of another embodiment of a structure including an electrode current collector, an electrode layer, a separator layer, and a counter electrode current collector for an electrode assembly, the structure including a population of spacer structures within the electrode layer, taken along the YX plane. [Figure 7A] FIG. 10 is a cross-sectional view of another embodiment of a structure for an electrode assembly including portions of first and second unit cells and including populations of spacer structures within the first and second electrode layers thereof, viewed in the YX plane. [Figure 7B] FIG. 10 is a cross-sectional view of another embodiment of a structure for an electrode assembly including portions of first and second unit cells and including populations of spacer structures within the first and second electrode layers thereof, viewed in the YX plane. [Figure 7C] FIG. 10 is a cross-sectional view of another embodiment of a structure for an electrode assembly including portions of first and second unit cells and including populations of spacer structures within its first and second electrode layers, passing through a shared electrode current collector, viewed in the YX plane. [Figure 8A] 1A-1C are plan views of embodiments of spacer structures formed on electrode structures and / or spacer layers for an electrode assembly. [Figure 8B] 1A-1C are plan views of embodiments of spacer structures formed on electrode structures and / or spacer layers for an electrode assembly. [Figure 8C] 1A-1C are plan views of embodiments of spacer structures formed on electrode structures and / or spacer layers for an electrode assembly. [Figure 8D] 1A-1C are plan views of embodiments of spacer structures formed on electrode structures and / or spacer layers for an electrode assembly. [Figure 8E] 1A-1C are plan views of embodiments of spacer structures formed on electrode structures and / or spacer layers for an electrode assembly. [Figure 8F] 1A-1C are plan views of embodiments of spacer structures formed on electrode structures and / or spacer layers for an electrode assembly. [Figure 8G] 1A-1C are plan views of embodiments of spacer structures formed on electrode structures and / or spacer layers for an electrode assembly. [Figure 8H] 1A-1C are plan views of embodiments of spacer structures formed on electrode structures and / or spacer layers for an electrode assembly. [Figure 9] A schematic diagram of an embodiment of the electrode layer 116 is shown, with representative dimensions and its sub-volumes. [Figure 10] A schematic diagram of an embodiment of the electrode layer 116 is shown, with representative dimensions and its sub-volumes. [Figure 11A] FIG. 2A is a cross-sectional view of one embodiment of a wound electrode assembly, and is an enlarged cross-sectional view of the wound electrode assembly of FIG. 2A showing sections of the first and second unit cells of the wound electrode assembly. [Figure 11B] FIG. 2A is a cross-sectional view of one embodiment of a wound electrode assembly, and is an enlarged cross-sectional view of the wound electrode assembly of FIG. 2A showing sections of the first and second unit cells of the wound electrode assembly. [Figure 12] FIG. 10 is a cross-sectional view of another embodiment of a wound electrode assembly. DETAILED DESCRIPTION OF THE INVENTION

[0011] definition As used herein, "a," "an," and "the" (i.e., singular) refer to plural referents unless the context clearly indicates otherwise. For example, in one example, a referent to "an electrode" includes both a single electrode and multiple similar electrodes.

[0012] As used herein, "about" and "approximately" refer to plus or minus 10%, 5%, or 1% of the stated value. For example, in one example, about 250 μm includes 225 μm to 275 μm. As a further example, in one example, about 1,000 μm includes 900 μm to 1,100 μm. Unless otherwise indicated, all numerical values ​​expressing quantities (e.g., measurements, etc.) and the like used in the specification and claims should be understood in all instances as modified by the term "about." Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and appended claims are approximations. Each numerical parameter should be construed in light of the number of reported significant digits by applying ordinary rounding techniques.

[0013] "Anode," as used herein in the context of a secondary battery, refers to the negative electrode of the secondary battery.

[0014] As used herein, "anode active" means a material suitable for use in the anode of a secondary battery.

[0015] "Cathode," as used herein in the context of a secondary battery, refers to the positive electrode of the secondary battery.

[0016] As used herein, "cathode active" means a material suitable for use in the cathode of a secondary battery.

[0017] As used herein in the context of the state of a secondary battery, "state of charge" refers to a state in which a secondary battery is charged to at least 75% of its rated capacity. For example, a battery can be charged to at least 80% of its rated capacity, at least 90% of its rated capacity, or even at least 95% of its rated capacity, such as 100% of its rated capacity.

[0018] As used herein, "C-rate" refers to a measure of the rate at which a secondary battery is charged or discharged, and is defined as the discharge current divided by the theoretical current draw at which the battery would deliver its nominal rated capacity in 1 hour. For example, a C-rate of 1 C indicates a discharge current that will discharge the battery in 1 hour, a 2C rate indicates a discharge current that will discharge the battery in 1 / 2 hour, a C / 2 rate indicates a discharge current that will discharge the battery in 2 hours, etc.

[0019] As used herein in the context of the state of a secondary battery, a "discharged state" refers to a state in which a secondary battery has discharged to less than 25% of its rated capacity. For example, a battery can be discharged to less than 5% of its rated capacity, such as less than 10% of its rated capacity, less than 20% of its rated capacity, or even 0% of its rated capacity.

[0020] As used herein, "cycling" in the context of cycling a secondary battery between a charging state and a discharging state refers to charging and / or discharging the battery to transition it in a cycle from a first state, either a charging state or a discharging state, to a second state that is the opposite of the first state (i.e., to a charging state if the first state was discharging, or to a discharging state if the first state was charging), and then returning the battery to the first state to complete the cycle. For example, a single cycle of a secondary battery between a charging state and a discharging state can include, if in a charging cycle, charging the battery from the discharging state to the charging state, then discharging it back to the discharging state to complete the cycle. Also, if in a discharging cycle, a single cycle can include discharging the battery from the charging state to the discharging state, then charging it back to the charging state to complete the cycle.

[0021] As used herein, the "Y-axis," "X-axis," and "Z-axis" refer to mutually perpendicular axes (i.e., each is orthogonal to the other). For example, the "Y-axis," "X-axis," and "Z-axis" used herein are analogous to a Cartesian coordinate system used to define three-dimensional aspects or orientations. As such, the description of elements of the inventive subject matter herein is not limited to the particular axis or axes used to describe the three-dimensional orientation of the elements. In other words, when referring to three-dimensional aspects of the inventive subject matter, these axes can be interchangeable.

[0022] As used herein, the "Y direction," "X direction," and "Z direction" refer to directions that are perpendicular to one another (i.e., perpendicular to one another). For example, the "Y direction," "X direction," and "Z direction" as used herein may be generally parallel to the Y axis, X axis, and Z axis, respectively, of a Cartesian coordinate system used to define three-dimensional aspects or orientations.

[0023] As used herein in the context of cycling between a charged state and a discharged state of a secondary battery, "repeated cycling" refers to repeating a cycle from a discharged state to a charged state or from a charged state to a discharged state more than once. For example, repeating cycling between a charged state and a discharged state can include repeating a cycle from a discharged state to a charged state at least twice, such as charging from a discharged state to a charged state, discharging back to the discharged state, charging again to a charged state, and finally discharging back to the discharged state. As yet another example, repeating cycling between a charged state and a discharged state at least twice can include discharging from a charged state to a discharged state, charging back to the charged state, discharging again to the discharged state, and finally charging back to the charged state. As a further example, repeating cycling between a charged state and a discharged state can include repeating at least five cycles, or even at least ten cycles, from a discharged state to a charged state. As a further example, cycling between a charged state and a discharged state can include cycling from a discharged state to a charged state at least 25, 50, 100, 300, 500, or even 1000 times.

[0024] As used herein in the context of secondary batteries, "rated capacity" refers to the capacity of a secondary battery to supply a specified current over a period of time, measured under standard temperature conditions (25°C). For example, rated capacity can be measured in ampere-hours, which is the product of current and time, by either determining the current output in a specified time or determining the time for which current can be output at a specified current. For example, for a battery rated at 20 ampere-hours, a rated current of 2 amperes indicates that the battery is designed to output current for 10 hours. Conversely, a rated time of 10 hours indicates that the battery is designed to output 2 amperes for 10 hours. In particular, the rated capacity of a secondary battery can be given as the rated capacity at a specified discharge current, such as a C-rate, where the C-rate is a measure of the rate at which the battery discharges relative to its capacity. For example, a C-rate of 1C indicates a discharge current at which the battery will discharge in 1 hour, 2C indicates a discharge current at which the battery will discharge in 1 / 2 hour, C / 2 indicates a discharge current at which the battery will discharge in 2 hours, etc. So, for example, a battery rated at 20Amp·hr at a C-rate of 1C will give a discharge current of 20Amp in 1 hour, but a battery rated at 20Amp·hr at a C-rate of 2C will give a discharge current of 40Amp in 1 / 2 hour, and a battery rated at 20Amp·hr at a C-rate of C / 2 will give a discharge current of 10Amp in 2 hours.

[0025] As used herein in the context of an electrode assembly of a secondary battery, the "stacking direction" refers to the direction in which structures within the electrode assembly are stacked relative to one another. According to certain embodiments, the stacking direction may be generally parallel to the shortest distance between structures within a unit cell of the electrode assembly.

[0026] As used herein in the context of an electrode assembly of a secondary battery, the term "stacking sequence" refers to those structures within a unit cell (e.g., unit cell portions of an electrode current collector, an electrode layer, a separator layer, a counter electrode layer, and a unit cell portion of a counter electrode layer) and / or sections of such structures encountered when traversing the electrode assembly in the stacking direction. According to one embodiment, in the case of a prismatic electrode assembly, the stacking sequence of unit cells includes structures of unit cells joined by first ends of the unit cells and second ends of the unit cells in the stacking direction. According to another embodiment, in the case of a wound electrode assembly, the stacking sequence of unit cells corresponds to those sections of unit cells joined by first ends of the unit cells and second ends of the unit cells in the stacking direction, and these sections are located within the same winding of the electrode assembly.

[0027] As used herein, a "wound electrode assembly" refers to an electrode assembly in which an electrode and counter-electrode structure is wound around an inner region of the electrode assembly, such that the electrode assembly includes multiple windings, each with an increasing diameter as the radius from the inner region of the electrode assembly increases. According to certain embodiments, the wound electrode assembly has a stacking direction that is parallel to a direction parallel to the radius R from the inner region to the outer region of the wound electrode assembly, and one or more electrode layers in the wound electrode assembly have a width dimension W measured in a first direction parallel to the stacking direction from the inner region of the electrode assembly to the outer region of the electrode assembly. E , a height dimension H measured in a second direction perpendicular to the stacking direction E , and a length dimension L measured in a third direction perpendicular to the stacking direction and the second direction E According to one embodiment, when measured in cylindrical coordinates having mutually orthogonal coordinates R (radius), Z (height), and A (azimuth), the stacking direction is generally parallel to the radius R, the second direction is generally parallel to the Z direction (height direction), and the third direction is measured along the angular direction A with respect to the total number of turns within the electrode assembly.

[0028] As used herein, "cylindrical coordinates" refers to a coordinate system that specifies a position in space by a height (Z) from a selected origin that serves as a reference axis, a distance R (radius) from the reference axis (Z axis), and an angular position or azimuth angle A, where R, Z, and A are mutually orthogonal coordinates.

[0029] As used herein, "orthogonal directions" refer to directions in a selected coordinate system that are mutually perpendicular to one another. For example, in a Cartesian coordinate system, orthogonal directions are directions parallel to the X, Y, and Z axes of the coordinate system. As another example, in a cylindrical coordinate system, orthogonal directions are directions defined along mutually perpendicular R (radius), Z (height), and azimuth (A) coordinates.

[0030] As used herein, a "prismatic electrode assembly" refers to an electrode assembly including an electrode and counter electrode structure having a series of layered sheets stacked alternately in a stacking direction. According to certain embodiments, the prismatic electrode assembly has a stacking direction parallel to the Y axis, and one or more electrode layers in the wound electrode assembly have a width dimension W measured in a first direction parallel to the stacking direction. E , a height dimension H measured in a second direction parallel to the Z axis E , and a linear dimension L measured in a third direction parallel to the X axis. E where X, Y and Z are mutually orthogonal Cartesian axes.

[0031] A "winding," as used herein with respect to a wound electrode assembly, includes a segment of a unit cell that extends from a starting point to an ending point that is rotated 360° from the starting point along the azimuthal direction A in cylindrical coordinates.

[0032] Detailed Description In general, embodiments of the present disclosure are directed to an energy storage device 100, such as a secondary battery 102, that is cycled between a charged state and a discharged state, and a method for manufacturing the same, as shown in Figure 1A. The secondary battery 102 includes a battery housing 104, an electrode assembly 106, and carrier ions, and may also include an electrolyte, such as a non-aqueous electrolyte solution, within the battery housing.

[0033] Furthermore, in certain embodiments, aspects of the present disclosure provide an electrode assembly 106 that can offer particular advantages when incorporated into an energy storage device 100, such as a battery, capacitor, or fuel cell. In one embodiment, the electrode assembly 106, and the secondary battery 102 including the electrode assembly 106, have a configuration and / or structure selected to accommodate at least one of electrode growth, swelling, and / or expansion that may otherwise occur during charging and / or discharging of the secondary battery including the electrode assembly 106. For example, the electrode assembly 106 can accommodate electrode growth, swelling, and / or expansion that may occur during an initial formation stage when the secondary battery 102 is initially charged from a discharged state to a charged state. The electrode assembly 106 may also be configured to accommodate growth, swelling, and / or expansion that may occur during cycling of the secondary battery 102.

[0034] According to certain embodiments, when transitioning from a discharged state to a charged state, carrier ions, such as one or more of lithium, sodium, potassium, calcium, and magnesium, migrate between the positive and negative electrodes of the battery. Then, when the carrier ions reach the electrode, they may intercalate, or alloy, within the electrode material, increasing the size and volume of the electrode. Conversely, when the transition from a charged state to a discharged state is reversed, the ions may deintercalate, or dealloy, causing the electrode to shrink. This alloying and / or intercalation, and dealloying and / or deintercalation, can result in significant volume changes in the electrode. In yet another embodiment, the transport of carrier ions from the electrode can increase the size of the electrode, for example, by increasing the electrostatic repulsion of the remaining material layers (including, for example, LCO and some other materials). Other mechanisms that can cause swelling in secondary batteries 102 include, for example, the formation of an SEI on the electrode, decomposition of the electrolyte and other components, and even gas formation. In one embodiment, when a secondary battery is charged from a discharged state to a charged state, where the charged state is at least 75% of the rated capacity of the secondary battery, and the discharged state is less than 25% of the rated capacity of the secondary battery, the electrode may include an electrode active material layer having a capacity that accepts more than one mole of carrier ions per mole of electrode active material, causing swelling of the electrode and / or electrode assembly 106. Thus, not only do the electrodes repeatedly expand and contract during charge and discharge, but other swelling mechanisms can also cause strain in the electrode assembly 106, resulting in reduced performance and even potential failure of the secondary battery.

[0035] Additionally, an initial formation process performed to initially form a secondary battery by an initial charging process in which the secondary battery is charged from a discharged state to a charged state can cause strain within the electrode assembly by similar mechanisms, such as swelling of the electrode assembly due to, for example, growth and / or swelling of the electrode active material during the formation process. That is, during the manufacture of a secondary battery 102 including an electrode assembly 106, an initial formation process can be performed that includes at least one initial charging cycle of the secondary battery 102, which can be performed under carefully controlled conditions, including one or more of current, temperature, and duration, to promote the formation of desired structures and contacts between components of the secondary battery 102. The initial formation process can include only a single initial charging cycle or can include multiple charging cycles (e.g., charging and discharging the secondary battery in one or more cycles), depending on the particular battery structure and composition. In one embodiment, the initial formation process can include a series of partial charge and / or discharge cycles. These series of partial charge and / or discharge cycles may, for example, be a charging process that at least partially charges the secondary battery (e.g., to 10% of its full capacity), followed by a subsequent discharging process that at least partially discharges the secondary battery (e.g., to 5% of its full capacity), which, depending on the characteristics of the formed secondary battery, may then be followed by a further charging process that at least partially or even fully charges the secondary battery, and / or further charge and / or discharge processes. According to one embodiment, the initial formation process may be performed as a final step during manufacture to bring the secondary battery 102 to its full power and / or capacity.

[0036] 3A-3C , according to certain embodiments, a population of spacer structures 400 can be provided as part of the electrode assembly 106 to at least partially accommodate electrode growth that may occur during the formation process. According to certain embodiments, the population of spacer structures 400 can be positioned relative to the expanding electrode active material in the electrode layer 116, such as within and / or around the electrode active material layer 125, to define voids and / or spaces between the electrode active material and adjacent structures, such as the adjacent separator layer 130. In one embodiment, the voids and / or spaces can provide a volume in which the electrode active material can grow, such as during the formation stage, thereby allowing for expansion of the electrode active material without causing undue strain on the electrode assembly 106. As a result, in certain embodiments, by providing a population of spacer structures 400 within the electrode assembly 106, a secondary battery 102 can be formed that exhibits less distortion and / or deformation of structures therein due to expansion of the electrode active material, which may occur during the formation process and / or during repeated cycling of the secondary battery 102 between charged and discharged states.

[0037] 1A and 1B and 3B, in one embodiment, the electrode assembly 106 includes a group of electrode structures 110, a group of counter electrode structures 112, and an insulating separator 130 that electrically insulates the electrode structures 110 from the counter electrode structures 112. As shown in these figures, the electrode structures 110, the counter electrode structures 112, and the insulating separator 130 may comprise a series of alternating stacked layers. In one embodiment, the group of electrode structures 110 may include a group of electrode current collectors 114 and a group of electrode layers 116, which may include an electrode active material. The group of electrode layers 116 may include, for example, first and second electrode layers 116a, 116b disposed on opposite sides of the electrode current collector 114. The group of counter electrode structures 112 may include a group of counter electrode current collectors 118 and a group of counter electrode layers 120, which may include a counter electrode active material. The population of counter electrode layers 120 can include, for example, first and second counter electrode layers 120 a , 120 b disposed on opposite sides of the counter electrode current collector 118 .

[0038] According to certain embodiments, the electrode assembly 106 can include a number of different sizes, shapes, and configurations. For example, with reference to Figures 1A and 1B, in one embodiment, the electrode assembly includes a series of electrode and counter-electrode structures 110, 112 including a series of laminated sheets stacked in a stacking direction in a first direction (e.g., parallel to the Y-axis). In an embodiment such as that shown in Figure 1A, the electrode structure 110 including the electrode layer 116 has a height dimension H measured in a second direction perpendicular to the stacking direction (e.g., parallel to the Z-axis). E , and a length dimension L measured in a third direction perpendicular to the stacking direction and the second direction (e.g., parallel to the X axis). E , as well as a width dimension W measured along the stacking direction (e.g., parallel to the Y axis) E 1B, the electrode structure 110, including the electrode layer 116, has a height dimension H E It has.

[0039] 2A, 2B, and 11A-11B, one embodiment of an electrode assembly 106 is shown in which the electrode and counter-electrode structures 110, 112 are configured in a wound electrode assembly 106 having a plurality of windings or turns 205, in which the electrode and counter-electrode sheets 110, 112 are spirally wound from an inner region 200 of the electrode assembly 106 to an outer region 202 of the electrode assembly 106. Each winding 205 of the wound electrode assembly includes a segment of a unit cell extending from a starting point 207a to an ending point 207b, rotated 360° from the starting point along an azimuthal direction A (e.g., in cylindrical coordinates). According to this embodiment, the electrode structure 110 includes electrode layers 116 that extend along a height dimension H measured parallel to the Z axis. E , width dimension W measured in the stacking direction E , which corresponds to a direction generally parallel to a radius R from the inner region 200 of the electrode assembly 106 to the outer region 202 of the electrode assembly 106 in the case of a wound configuration, along which a series of windings 205a, 205b meet. Furthermore, in the illustrated embodiment, the stacking direction of the electrode assembly along R is in a direction perpendicular to the Z axis. That is, according to one embodiment, the stacked stack series 800 is stacked in the stacking direction R, and the height He of the electrode layer 116 is measured in a second direction (e.g., the Z direction) perpendicular to the stacking direction R. According to one embodiment, the length dimension L of the wound electrode layer 116 is E is measured in a third direction orthogonal to the stacking direction and the second direction, the third direction being measured along an angular and / or azimuthal direction A (e.g., in cylindrical coordinates) for the total number of turns within the electrode assembly from an inner region of the electrode assembly to an outer region of the electrode assembly. In one embodiment, the length L of the wound electrode layer is E is the total length of the electrode layer 116 along the spiral path 208 of the wound electrode from the inner region 200 to the outer region 202, with the direction T of this spiral path being perpendicular to the Z axis and the stacking direction R at each point along the spiral path 208. In the embodiment shown in FIG. 2A, the electrode assembly 106 has a cross-section that appears to have an oval shape along the Z axis. In the embodiment shown in FIG. 2B, the electrode assembly 106 has a cross-section that appears to have a circular shape along the Z axis.

[0040] 1A-1B and 3A-3B, according to one embodiment, the electrode assembly 106 includes a group of unit cells 500, and each unit cell 500 includes, in a stacked stack 800, a unit cell portion of an electrode current collector layer 114, an electrode layer 116, a separator layer 130, a counter electrode layer 120, and a unit cell portion of a counter electrode current collector layer 118. Referring to FIGS. 3A-3C, in one embodiment, the unit cell 500 includes a unit cell portion of the electrode current collector layer 114 and a unit cell portion of the counter electrode current collector layer 118, a first electrode layer 116a of the electrode structure 110 disposed on one side of the electrode current collector layer 114, and a first counter electrode layer 120a of the counter electrode structure 112 disposed on one side of the counter electrode current collector layer 118 opposite the electrode current collector layer 114. The electrode and counter electrode layers in the unit cell may be arranged such that the electrode layer is adjacent to a first side 133 a of the separator 130 and the first counter electrode material layer is adjacent to an opposing second side 133 b of the separator 130. According to a specific embodiment, the separator 130 can electrically insulate the electrode layer 116 from the counter electrode layer 120 in the unit cell 500, and when an electrode assembly including the unit cell is used as part of a secondary battery during repeated cycling between a charged state and a discharged state of the battery, carrier ions can be exchanged primarily through the separator 130 between the electrode layer 116 and the counter electrode layer 120 in the unit cell.

[0041] Furthermore, according to certain embodiments, the unit cell portions of the electrode current collector layer and / or counter electrode current collector layer are those portions that participate in the electrochemical reaction within the unit cell, such as when supplying current therebetween to facilitate the transfer of electrons between the unit cell portions of the electrode current collector layer and / or counter electrode current collector layer. For example, with reference to FIG. 1A , a first unit cell 500a includes a unit cell portion of the electrode current collector 114 that participates in the electrochemical reaction within the unit cell 500a, while an adjacent second unit cell 500b includes a unit cell portion of the shared electrode current collector 114 that participates in the electrochemical reaction within the second unit cell 500b. For example, the unit cell portion of the current collector may be half of a current collector divided along the XZ plane in the Y direction in an embodiment such as that shown in FIG. 4A , or may have a different configuration depending on the configuration and other characteristics of the electrode assembly 106.

[0042] The stacking sequence 800 within the unit cell 500 includes those structures within the unit cell 500 (e.g., unit cell portions of the electrode current collector, electrode layer, separator layer, counter electrode layer, and unit cell portions of the counter electrode layer) and / or sections of such structures encountered when traversing the electrode assembly in the stacking direction. The stacking direction is the direction in which the structures within the electrode assembly are stacked relative to one another. According to certain embodiments, the stacking direction may be generally parallel to the shortest distance between the structures within the unit cells of the electrode assembly. For example, in the case of the prismatic electrode assembly of FIGS. 1A and 1B , the stacking direction is parallel to axis Y, which is the direction in which the electrode layers 116 are stacked relative to one another, and the stacking sequence 800 includes those members of the unit cells encountered when moving along axis Y, i.e., unit cell portions of the electrode current collector 114, electrode layer 116, separator layer 130, counter electrode layer 120, and counter electrode current collector 118. 2A and 2B, the stacking direction is parallel to the direction R from the inner region 200 of the electrode assembly 106 to the outer region 202 of the electrode assembly 106, as shown in FIGS. 11A-11B, with each outer winding 205b stacked on top of the inner winding 205. As a result, the stacking sequence 800 of the electrode assembly 106 in this embodiment includes those components of the unit cells encountered when moving along the direction R, namely, the unit cell portions of the electrode current collector 114, the electrode layer 116, the separator layer 130, the counter electrode layer 120, and the counter electrode current collector 118. Thus, each stacked series 800 of individual unit cells 500 in this embodiment is bounded by a section of the unit cell portion of the electrode current collector 114 and a section of the unit cell portion of the counter electrode current collector along direction R within the same winding 205 of the electrode assembly.

[0043] According to one embodiment, the unit cell 500 has a width W measured in the stacking direction of the stacked continuum 800 from the unit cell portion of the electrode current collector 114 to the unit cell portion of the counter electrode current collector 118, as shown, for example, in FIG. 3B and FIGS. 4-6, which illustrate an embodiment of a unit cell 500 within a prismatic electrode assembly. UC Furthermore, in the case of a spirally wound battery, as shown in FIGS. 11A-11B, the width W measured at any winding portion 205 of the unit cell 500 along the winding path 208 of the electrode assembly UC corresponds to the width along the stacking direction R from the unit cell portion of the electrode current collector 114 to the unit cell portion of the counter electrode current collector 118, measured for the stack continuum within a unit cell that includes adjacent sections 502 of the electrode current collector and counter electrode current collector that are closest in the stacking direction (e.g., those sections 502 within the same winding part 205 along the stacking direction R of the winding path 208).

[0044] According to yet another embodiment, the electrode layer 116 has a width W measured in the stacking direction from the unit cell portion of the electrode current collector 114 adjacent to the electrode layer 116 to the separator layer 130 adjacent to the electrode layer 116. e With reference to the embodiment shown in FIG. 3B and FIGS. 4 to 6, in the case of a prismatic electrode assembly, the width W E is measured in the stacking direction between the first surface 115a of the electrode current collector layer 114 and the opposing first surface 131a of the separator layer 130. Similarly, in the case of a spirally wound battery, as shown in FIGS. 11A-11B, the width W measured for any one winding 205 along the winding path 208 of the electrode assembly is E corresponds to the width along the stacking direction R from the unit cell portion of the electrode current collector 114 to the separator layer 130 adjacent to the electrode layer 116, measured for a stack continuum including the nearest adjacent sections of the electrode current collector and separator in the stacking direction (e.g., those sections 502 within the same winding part 205 of the winding path 208 of the electrode assembly).

[0045] According to an embodiment, the electrode layer 116 further includes a height He measured from the top surface 119a to the bottom surface 119b of the electrode layer 116 in a direction perpendicular to the stacking direction. Referring to Figures 1A and 1B showing an embodiment of a prismatic electrode assembly, the height H E may be the dimension measured parallel to the Z direction perpendicular to the stacking direction in Y from the top surface 119a to the bottom surface of the electrode layer 116. As shown in FIGS. 1A and 1B, the height H E is the length direction L measured along the X direction E , and in the embodiment shown in FIG. 1B, the length L E is measured along the longest dimension of the electrode layer 116. With reference to the spiral wound electrode assembly embodiment shown in FIGS. 2A-2B, the height H E may be a dimension measured parallel to the Z direction perpendicular to the stacking direction in R.

[0046] According to one particular embodiment, the top surface 119a and the bottom surface 119b of the electrode layer 116 are spaced apart by a width W of the electrode structure at the ends of the electrode layer in a direction perpendicular to the stacking direction. E The top and bottom surfaces 119 a, 119 b may be coextensive with the surfaces of any physical structures within the electrode layer 116. For example, in one embodiment of the formed electrode assembly, the top and bottom surfaces 119 a, 119 b may include edge surfaces of the electrode active material layer 125 within the electrode layer 116, as shown in FIGS. 1A and 1B. As another example, in one embodiment, such as when spacer structures are disposed around the periphery of the electrode layer 116 and the electrode active material layer 125 is disposed within the peripheral spacer structure(s) (e.g., as shown in FIG. 5C), the top and bottom surfaces 119 a, 119 b may include the top and bottom surfaces of the spacer structures, which may be disposed at the top and bottom ends, respectively, of the electrode layer 116. As yet another example, in the electrode assembly prior to formation, a void 126 may exist between the electrode active material layer 125 and the separator, as shown in FIG. 4B, for example. Therefore, the height H Eis a dimension measured between their top and bottom surfaces 119 a, 119 b (e.g., as shown in FIG. 4B). Similarly, in one embodiment, the top and bottom surfaces 119 a, 119 b are coextensive with the top and bottom surfaces of spacer structures 400 that are disposed at the top and bottom ends, respectively, of the electrode layer 116, such as when spacer structures are disposed around the periphery of the electrode layer 116, with the electrode active material layer 125 and voids 126 disposed within the peripheral spacer structure(s) (e.g., as shown in FIGS. 5A and 5C).

[0047] According to an embodiment of the present specification, the electrode layer 116 further has a length Le measured from the first end surface 121a to the second end surface 121b in a direction perpendicular to the stacking direction and the height direction. E may be a dimension measured parallel to the X direction perpendicular to the stacking direction in Y and the height direction Z from the first end surface 121a to the second end surface 121b of the electrode layer 116. Referring to FIG. 1B showing another embodiment of a prismatic electrode assembly, the length L E may be the dimension measured from the first end surface 121a to the second end surface 121b of the electrode layer 116, parallel to the stacking direction in Y and the Z direction as shown, which is orthogonal to the X direction. With reference to the embodiment of the wound electrode assembly as shown in FIGS. 2A-2B, the length L E may be the total extent of the electrode layer 116 measured along the spiral path 208 of the wound electrode from the first end surface 121 a at the inner region 200 to the second end surface 121 b at the outer region 202 of the electrode assembly 106, the direction T of the spiral path being perpendicular to the Z axis and the stacking direction R at each point along the spiral path. That is, the length L of the wound electrode layer 116 according to a particular embodiment E can be the total extent of the electrode layer 116 measured along all points in the winding path in a direction T perpendicular to the Z axis and the stacking direction.

[0048] According to one embodiment, the length L E is the longest dimension of the electrode layer 116, e.g., the dimension L parallel to the X-axis in FIG. 1B. Ewhich corresponds to the dimension W E or H E In another embodiment, such as that shown in FIG. 1A, when two dimensions of the electrode layer are equal, the length L E can be chosen to be the dimension along the X direction, and the height H E 1A, it can be seen that, although the X and Z directions may be interchangeable in such embodiments if the lateral sizes of the electrode layer 116 are equal, the longest dimension is equal to the dimension wound in direction T along the spiral path. For example, if a wound electrode 116 such as shown in FIGS. 2A-2B is unwound into a flattened embodiment such as shown in FIGS. 1A-B, the dimension along the spiral path in direction T is the height dimension H measured in a direction parallel to the X direction. E , or the width dimension W of the electrode layer measured in a direction parallel to the Y axis (e.g., in direction R in the case of a wound configuration) E Therefore, the length L of the wound electrode 116 in one particular embodiment is E may have a longest dimension of the electrode corresponding to the dimension of the electrode layer that is wound to form the wound electrode assembly 106.

[0049] According to one embodiment, the first and second end surfaces 121a, 121b of the electrode layer 116 are used to define the length L of the electrode layer 116. E Therefore, the width W of the electrode structure at both ends of the electrode layer in the length direction Le can be determined. EThe first and second end surfaces 121 a, 121 b may be coextensive with the surfaces of any physical structures within the electrode layer 116. For example, in the formed electrode assembly, the first and second end surfaces 121 a, 121 b may include end surfaces of the electrode active material layer 125 within the electrode layer 116. As another example, in one embodiment, when spacer structures are disposed around the periphery of the electrode layer 116 and the electrode active material layer 125 is disposed within the peripheral spacer structure(s) (e.g., as shown in FIG. 5B ), the first and second end surfaces 121 a, 121 b may include end surfaces of the spacer structures, which may be disposed at the first and second ends, respectively, of the electrode layer 116. As yet another example, in the electrode assembly prior to formation, a void 126 may exist between the electrode active material layer 125 and the separator, as shown in FIG. 4A , for example. Similarly, in one embodiment, when spacer structures are disposed around the periphery of the electrode layer 116, with the electrode active material layer 125 and voids 126 disposed within the peripheral spacer structure(s) (e.g., as shown in FIG. 5A), the first and second end surfaces 121 a, 121 b are coextensive with the end surfaces of the spacer structures disposed at the first and second ends, respectively, of the electrode layer 116.

[0050] According to yet another embodiment, the width W of the electrode layer 116 for an electrode layer 116 having an irregular or sawtooth interface between the electrode current collector 114 and / or separator layer 130 E Such irregular interfaces can be present, for example, when portions of the separator material and / or electrode current collector material extend into the electrode layer 116, such as when portions of the separator material and / or electrode current collector material act as spacer structures 400, such as shown in FIG. 4C or other configurations. In such embodiments where a sawtooth or irregular interface is present, the width W Ecan be measured by locating one or more of first and second interface surfaces 123a and 123b that identify one or more of the electrode current collector and / or separator surfaces 115a, 131a between the unit cell portion of the electrode current collector 114 adjacent to the electrode layer 116 and the separator layer adjacent to the electrode layer 116 on the opposite side of the electrode layer from the unit cell portion of the electrode current collector. That is, one or more of the first surface 115a of the electrode current collector 114 and the first surface 131a of the separator layer 130 can be defined according to the interface surfaces 123a, 123b that identify the interface between the electrode current collector layer 114 and / or separator layer 113 and the electrode layer 116 (e.g., as in FIG. 3B ). For example, according to one embodiment, the first boundary surface 123a, which is established as the first surface 115a of the unit cell portion of the electrode current collector layer 114, may be defined as a plane such that (i) at least 80% of the area between the first boundary surface and any other plane parallel to the first boundary surface within the stacking sequence of the unit cells and on a second side of the first boundary surface in a direction away from the separator layer 130, comprises the electrode current collector material, and (ii) the area of ​​any other plane parallel to the first boundary surface on the first side of the first boundary surface within the stacking sequence of the unit cells, toward the separator, comprises less than 80% of the electrode current collector material. That is, the boundary surface (first surface) of the electrode current collector may be established to correspond to its position along the stacking direction within the unit cell when moving from the separator to the electrode current collector, where at least 80% of the material encountered within the plane is the current collector material in a direction perpendicular to the stacking direction. As can be appreciated, in further embodiments, the interface (first surface) can be provided where requirement (i) is that at least 90% of the area(s) is current collector material, and / or at least 95% of the area(s) is current collector material, and / or at least 98% of the area(s) is current collector material.Thus, if the interface between the current collector layer 114 and the electrode layer 116 is relatively flat and / or smooth, it may be possible to see that the first surface 115a is equivalent to an interface where 100% of the material within this interface is electrode current collector, but any plane on the first side of the interface toward the separator layer contains little or no electrode current collector within the interface. That is, according to embodiments herein, the interface defined herein can be established for structures where the interface between the electrode current collector and the electrode layer 116 is relatively sawtooth and / or uneven, as well as structures where the interface is more clearly defined.

[0051] Similarly, the second boundary surface 123b, which is defined as the first surface 131a of the separator 130, may be a plane, in which case (i) at least 80% of the area of ​​the second boundary surface and any other plane parallel to the second boundary surface within the stacking sequence of unit cells and on a first side of the second boundary surface in a direction away from the electrode current collector 114 within the unit cell comprises the separator material, and (ii) the area of ​​any other plane parallel to the second boundary surface on a second side of the second boundary surface toward the electrode current collector 114 within the stacking sequence of unit cells comprises less than 80% of the separator material. In other words, the boundary surface (first surface) of the separator layer may be defined to correspond to its position along the stacking direction within the unit cell when moving from the electrode current collector to the separator, where at least 80% of the material encountered within that plane along a direction perpendicular to the stacking direction is the separator material. As can be understood, in further embodiments, the interface (first surface) can be established when requirement (i) is met when at least 90% of the area(s) is / are separator material, and / or when at least 95% of the area(s) is / are current separator material, and / or when at least 98% of the area(s) is / are separator material. Thus, if the interface between the separator layer 130 and the electrode layer 116 is relatively flat and / or smooth, the first surface 131a can be considered to be equivalent to the interface, with 100% of the material within this interface being separator material, but any plane of the second side of the interface toward the electrode current collector layer containing little or no separator material within the interface. That is, according to embodiments herein, the interface defined herein can be established for structures in which the interface between the separator layer 130 and the electrode layer 116 is relatively sawtooth and / or uneven, as well as for structures in which the interface is more clearly defined.

[0052] Furthermore, according to certain embodiments, the first and second interface surfaces 123a, 123b shown in FIG. 3B are planar with dimensions along Cartesian coordinates (X, Y, and Z), but it can be understood that the interface surfaces 123a, 123b that describe the interface between surfaces within the unit cell along the stacking direction may also include curved interfaces or interfaces having other shapes. For example, with reference to the wound electrode assemblies of FIGS. 2A and 2B and 11A and 11B, the first and second interface surfaces may have a curved shape that generally corresponds to the spiral windings of the electrode layer 116. According to certain embodiments, the width W of the electrode layer 116 may be 1 / 2 . E can be measured as the distance between the first and second interface surfaces 123a, b of the unit cell portion of the electrode current collector and the separator layer 130 in the stacked sequence. According to yet another embodiment, when the first and second surfaces 115a, 131a of the electrode current collector 114 and the separator are relatively smooth and / or easily identifiable, this width W E may simply be equal to the distance between surface 115a and surface 131a. According to yet another embodiment, width W E may be the width between one or more of the first and / or second interface surfaces located on the electrode current collector and / or separator having a relatively irregular shape and the surface of the other of the electrode current collector and / or separator that is relatively smooth and / or easily identifiable. That is, the width W E can be understood to be the range of dimensions between the surface of the electrode current collector and the surface of the separator, where these surfaces are defined as either readily identifiable interfacial surfaces between structures and / or boundary surfaces defined to correspond to those surfaces, and meet the above criteria.

[0053] According to one embodiment, the electrode layer 116 has a volume Ve, which is bounded by the unit cell portion of the electrode current collector 114, the separator layer 130, the top surface 119a of the electrode layer 116, the bottom surface 119b of the electrode layer 116, the first end surface 121a of the electrode layer 116, and the second surface 121a of the electrode layer 121a. For example, with reference to Figures 3A and 3B, the volume Ve is the area of ​​the electrode layer L measured between the first and second end surfaces 121a, 121b. E The height H of the electrode layer 116 measured between the top surface 119a and the bottom surface 119b is E and multiplying the width W measured between the first surface 115a of the unit cell portion of the electrode current collector layer 114 and the first surface 131a of the separator layer 130. E It is calculated as multiplication of the width W E may be measured by determining the distance between a first interface 123a and a second interface 123b, which are designated as a first surface 115a of the unit cell portion of the electrode current collector layer 1124 and a first surface 131a of the separator layer, as discussed herein.

[0054] 9, according to one embodiment, the volume V of the electrode layer 116 can be calculated even when the electrode layer has an irregular or non-uniform shape in a dimension orthogonal to the width dimension We. For example, as shown in FIG. 9, the electrode layer 116 has a volume V as viewed in the XZ plane, as viewed along the stacking direction Y, and a dimension H E is the length L of the electrode layer 116 E Similarly, in other embodiments, the dimension L E is the height H of the electrode layer 116 E Both other dimensions L can vary along E and / or H Emay vary as a function of each other and / or as a function of width We. Thus, in certain embodiments, to determine the volume, the integral of the volume of the electrode layer 116 may be calculated to determine the volume Ve. The integral of the volume of the electrode layer 116 may be calculated according to any suitable mathematical method as would be understood by one of ordinary skill in the art. As an example of calculating such a volume integral, E can be set by determining the first and second boundary surfaces 123a, 123b of the unit cell portion of the electrode current collector and the separator within the unit cell (e.g., at the surfaces of these structures), and then determining the distance between the first end surface and the second end surface (length L E ), and the distance between the top and bottom surfaces (height H E ) can be used to calculate the volume of the electrode layer according to the following formula:

[0055] Volume=∫H E (l)×W E (l) × dl (L = 0 to L = L E (integrate over

[0056] Other means of determining the volume of the electrode layer 116 bounded by the unit cell portion of the electrode current collector, the separator layer, the top surface of the electrode layer, the bottom surface of the electrode layer, the first surface of the electrode layer, and the second surface of the electrode layer may also be used. For example, in one embodiment, multiple cross sections at various different points along X, Y, and Z may be taken along the XY, YZ, and XZ planes, and these planes may be used to construct a three-dimensional model that defines the total volume V of the electrode layer. E A computational technique is used to closely approximate the 3D structure of the electrode layer.

[0057] 3A-3C and 4-6, the electrode layer 116 includes a population of spacer structures 400 disposed therein. In one embodiment, the population of spacer structures 400 may be provided as part of the electrode layer 116 that physically separates the electrode material from the separator layer 130 prior to the formation process performed to form the secondary battery. The population of spacers 400 thus allows for voids to exist between the electrode material in the layer 116 and the separator 130, reducing any stresses that may arise during the formation process that may result in expansion of components of the electrode assembly 106, such as the electrode material. For example, as shown in the embodiment depicted in FIG. 5A, the electrode layer 116 includes a width W of the electrode layer 116, and a width W of the separator layer 130. E 5B , the electrode assembly 106 may include an electrode active material layer 125 extending at least partially along the width W of the electrode layer 116, and a void 126 occupying the remainder of the electrode layer 116. For example, the void 126 may be provided when the electrode assembly 106 is in a pre-formation stage before undergoing a formation process for charging and / or forming a secondary battery including the electrode assembly 106. In another embodiment, as shown in FIG. 5B , in a post-formation stage after undergoing a formation process, the electrode assembly 106 may expand during the formation stage to reduce the width W of the electrode layer 116. E , and may even extend to the interface with separator layer 130.

[0058] In one embodiment, the population of spacer structures includes a plurality of spacer structures that are arranged along a direction of the electrode layers that is perpendicular to the stacking direction within the electrode layer 116. For example, in the embodiment shown in FIG. 3C, the plurality of spacer structures are arranged along the length L of the electrode layer 116, which in certain embodiments may be the longest dimension of the electrode layer 116. E11A, the population of spacer structures 400 may be disposed at various points along the direction T of the spiral path of the wound electrode 116, which in certain embodiments may correspond to the longest dimension of the electrode layer. According to yet another embodiment, the population of spacer structures 400 in the electrode layer 116 may include only a single spacer structure 400, such as a single spacer structure extending at least partially along the periphery 404 of the electrode layer, as shown in the embodiment depicted in FIG. 8B. The population of spacer structures may be disposed along the electrode layer 116 at and / or adjacent the interface between the electrode layer 116 and the separator layer 130, e.g., at and / or adjacent the surface 131a of the separator layer 130, as shown in the embodiment depicted in FIG. 6. In the embodiment depicted in FIG. 6, the members of the population of spacer structures 400 are spaced apart from each other across the width W of the electrode layer. E 5A , the separator layer 130 extends only partially through the electrode active material layer 125. According to yet another embodiment, the population of spacer structures can be disposed along the electrode layer 116 at and / or adjacent to the interface between the electrode layer 116 and the unit cell portion of the electrode current collector 114, e.g., at and / or adjacent to the surface 115 a of the unit cell portion of the electrode current collector 114, and / or across the width W of the electrode layer 116 between the interface between the electrode layer 116 and the unit cell portion of the electrode current collector 114 and the separator layer 130, as shown in the embodiment depicted in FIG. E It can extend along.

[0059] According to yet another embodiment, the members of the group of spacer structures 400 are spaced from the surface 131 a of the separator layer 130 to the surface 115 a of the unit cell portion of the electrode current collector (e.g., the width W of the electrode layer 116). E a first portion 410a of the electrode layer 116 extending across the width W of the electrode layer 116 to a position flush with a surface 127 of the electrode active material layer 126 disposed adjacent to the unit cell portion of the electrode current collector 114; E5D) that has its second portion 410b extending only partially across the width W of the electrode layer 116. That is, the members of the same spacer structure may be E 5D, in one embodiment, one or more spacer structures 400 may extend from the surface 115a of the current collector to the W of the electrode layer that is coplanar with the surface 127 of the electrode active material layer. E and a first segment 410c within a section of the structure extending to a position along the W of the electrode layer that is flush with the surface 127 of the electrode active material layer. E and a second segment 410d extending from a position along the separator layer 130 to the surface 131a of the separator layer 130. The first and second segments 410c, 410d may, for example, be different segments of the spacer structure 400 that are fabricated separately but include the same spacer material, and / or may include first and second segments that each include a first and second spacer material, where the first and second spacer materials are different from one another. According to yet another embodiment, the spacer structure 400 may include a combination of first and second portions 410a, b and first and second segments 410c, d.

[0060] In certain embodiments, the electrode active material layer 125 can expand during the formation stage to substantially completely fill the voids 126 left in the pre-formation stage. In other embodiments, during the formation process, the electrode active material layer 125 expands to only partially fill the voids, leaving at least some residual voids 126 in the electrode layer 116 after formation. Such partial filling can be advantageous, for example, to accommodate any further expansion of the electrode active material or other materials that may occur during cycling of a secondary battery including the electrode assembly. According to certain embodiments, the electrode active material layer 125, either pre-formed and / or post-formed, can further include a porous layer such that, either pre-formed and / or post-formed, the electrode active material layer 125 itself can include voids that are independent of any voids provided by the presence of the spacers 400. For example, in one embodiment, electrode active material layer 125 (either at a pre- or post-formation stage) can include at least 10%, at least 25%, and / or at least 50% voids, measured as a percentage of the volume of voids per volume of electrode active material layer 125, and may typically include less than 70% voids, e.g., less than 60% voids, less than 50% voids, and / or less than 25% voids, such as voids in the range of about 10% to 70% of the volume of the electrode active material layer. Thus, by including any voids contained within electrode active material layer 125 itself, in one embodiment, electrode layer 116 during a post-formation stage can be formed to have a total volume V of the electrode layer. E less than 60% voids as a percentage of the total volume V of the electrode layer 116, e.g., less than 50% voids, less than 40%, less than 30%, less than 20%, and / or even about 10% or less voids, etc. EIn another embodiment, the electrode layer during the pre-formation stage comprises at least 40% voids as a percentage of the total volume of the electrode layer, e.g., at least 50% voids, at least 60% voids, at least 75% voids, and / or at least 90% voids as a percentage of the total volume of the electrode layer. That is, during the pre-formation stage, the voids of the electrode layer may be up to or equal to 90%, and during the post-formation stage, the voids may decrease to as little as 10%.

[0061] In one embodiment, the population of spacer structures 400 includes a material other than the electrode active material in the electrode active material layer 125. For example, in one embodiment, the population of spacer structures 400 includes a material that does not substantially increase in volume during the formation process performed to form the secondary battery and / or during the charge cycles of the secondary battery. As another example, the population of spacer structures can include a spacer material whose volume increases during the formation and / or charge cycles, but the increase is due to a lesser amount per mole of spacer material than any increase in volume per mole of electrode active material that occurs during the formation process and / or during the cycles of the secondary battery. For example, in one embodiment, the population of spacer structures can include a spacer material that can have a capacity to accept less than one mole of carrier ions per mole of spacer material when a secondary battery 102 including the electrode assembly 106 is charged from a discharged state to a charged state. Thus, the spacer material may exhibit less expansion than the electrode active material used in the electrode layer when the secondary battery is charged from a discharged state to a charged state, for example, if the layer of electrode active material has a capacity that accepts more than one mole of carrier ions per mole of electrode active material. The charged state of the secondary battery is at least 75% of the rated capacity of the secondary battery, and the discharged state is less than 25% of the rated capacity of the secondary battery. In one embodiment, the population of spacer structures 400 includes any one or more of materials suitable for use in separator layers and / or materials suitable for use as electrode and / or counter-electrode materials, such as any of those described elsewhere herein. According to another embodiment, the population of spacer structures 400 may include an electrode active material, such as any of the electrode active materials described elsewhere herein. According to one embodiment, the population of spacer structures includes materials that are relatively inert and / or non-reactive in operation and storage in a battery environment, such as inert and / or non-reactive in the electrochemical reactions that occur within the secondary battery 102.For example, in one embodiment, the population of spacer structures 400 can include a polymeric material, such as any of the polymeric materials described elsewhere herein that are suitable for separator layer 130. In one embodiment, the population of spacer structures 400 can include a non-porous spacer material. In another embodiment, the population of spacer structures 400 can include a porous spacer material, for example, a porous spacer material that provides a porosity to the structure of at least 10%, at least 25%, at least 50%, at least 75%, or even at least 90%. In one embodiment, the population of spacer structures 400 includes a spacer material that can provide sufficient mechanical strength to withstand pressures that may be applied during the formation process of the secondary battery 102 and / or during repeated cycling of the secondary battery, such as while substantially maintaining a predetermined size and shape during the formation process of the secondary battery 102 and / or during repeated cycling of the secondary battery 102.

[0062] According to yet another embodiment, the population of spacer structures 400 can include a spacer material with a relatively low conductivity, such that the overall conductivity of all of the spacer structures 400 in an electrode layer is lower than the conductivity of either and / or both of the electrode current collector layer and the counter electrode current collector, and even lower than the total conductivity of the electrode active material in the electrode layer 116. For example, according to one embodiment, the ratio of the conductivity of the electrode active material in an electrode layer to the total conductivity of all members of the spacer population in the electrode layer is at least 2:1, at least 5:1, and / or at least 50:1.

[0063] In one embodiment, the population of spacer structures may include a spacer material that is the same material as the separator layer 130. For example, in one embodiment, a width W defined by the width of the electrode layer may be used. EOne or more spacer structures may be provided extending from separator layer 130 (e.g., from second interface 123b defined in the separator layer) at least partially along the width of electrode layer 116. In yet another embodiment, the collection of spacer structures may include a spacer material that is the same material as the material of the electrode current collector layer. For example, in one embodiment, W defined by the width of electrode layer 116 may be provided. E A spacer structure may be provided extending from the unit cell portion of the current collector layer 114 (e.g., from a first interface 123a defined by the unit cell portion of the current collector layer) at least partially along the separator layer 114. In one embodiment, the spacer structure including the separator material may be fabricated as a unitary component with the separator layer, or the separator structure may be formed separately from the separator layer and provided within the electrode layer 116. In yet another embodiment, the ensemble of spacer structures may include the same spacer material as that of the electrode active material. According to yet another embodiment, the ensemble of spacer structures may include a spacer material that has the capacity to act as an electrode active material (e.g., the capacity to accept carrier ions), even if it is not the same as the electrode active material of the electrode active material layer 125. In one embodiment, the spacer material may include any of the electrode active materials described elsewhere herein, including one or more of lithium titanium oxide, graphene, tin, germanium, and transition metal oxides, as well as sulfides, phosphides, and nitrides thereof (e.g., for lithium secondary batteries including lithium sheet electrodes).

[0064] According to one particular embodiment, the collection of spacer structures 400 occupies a volume V of the electrode layer 116. EThe population of spacer structures 400 is provided in the electrode layer 116 in a configuration and distribution such that it occupies a total volume within the electrode layer 116 that is in the range of about 0.1% to about 35% of the volume V of the electrode layer 116. That is, according to certain embodiments, the population of spacer structures 400 comprises a total volume within the electrode layer 116 that is sufficient to provide voids 126 within the electrode assembly prior to formation. Furthermore, according to certain embodiments, the population of spacer structures 400 comprises a total volume within the electrode layer 116 that is small enough so that the presence of any spacer structures after formation does not significantly adversely affect cycling of the secondary battery between charge and discharge states. Thus, in one embodiment, the population of spacer structures 400 comprises a total volume within the electrode layer 116 that is in the range of about 0.1% to about 35% of the volume V of the electrode layer. E In another embodiment, the population of spacer structures occupies a total volume within the electrode layer that is at least 0.1%, such as at least 0.25%, at least 0.5%, at least 0.75%, and / or at least 1%, of the volume V of the electrode layer. E For example, the population of spacer structures occupies a total volume within the electrode layer 116 that is less than 35%, e.g., less than 25%, less than 10%, less than 5%, and / or less than 2%, of the volume V of the electrode layer. E 0.25% to 25% of the volume of the electrode layer, e.g., V E The total volume within the electrode layer 116 may be within the range of 0.5% to 10% of the total volume within the electrode layer 116 .

[0065] According to another embodiment, the total volume V of the electrode layer 116 EThe volume of the solid electrode active material layer 125 as a percentage of the width W of the unit cell increases following the formation process due to growth and / or expansion of the electrode active material layer. According to one embodiment, the electrode layer 116 includes a first volume of solid electrode active material before the formation process and a second volume of solid electrode active material after the formation process that is greater than the first volume. That is, according to certain embodiments, the formation process can be performed to increase the volume of the solid electrode active material in the electrode layer to a second volume that is at least 3%, at least 5%, at least 10%, at least 25%, at least 50%, at least 75%, and / or at least 100% greater than the first volume of the solid electrode active material in the electrode layer. Furthermore, while an increase in the volume of the solid electrode active material can occur, the width W of the unit cell before formation can be increased. UC The width of the unit cell shown after formation, W, compared to UC and / or the width W of the unit cell both before and after formation may, in some embodiments, be less than 1%, less than 0.5%, less than 0.25%, and / or less than 0.1%. UC may be substantially the same, so that the width of the unit cell 500 does not change substantially during the formation process.

[0066] According to yet another embodiment, a population of spacer structures 400 is distributed and / or provided within the electrode layer 116 such that at least one member of the population (i) occupies a volume V of the electrode layer 116 E and (ii) located within each sub-volume of the electrode layer 116 that is bounded on all sides by (aa) the unit cell portion of the current collector 114, (bb) the separator layer 130, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer. E Subvolume SV in E can be calculated by appropriate mathematical methods, as will be understood by those skilled in the art. Referring to FIG. 10, according to one example, the sub-volume SV E is calculated by the length L of the electrode layer 116 according to the following formula: E can be calculated between any two points along

[0067] Sub volume SV E =∫H E (l)×W E (l)×dl (integrate from L=L1 to L=L2)

[0068] Therefore, the total volume V of the electrode layer 116 E For any subvolume, as defined above, that corresponds to 10% or more of the total, the population of spacer structures distributed within the electrode layer 116 is such that at least one member of this population is located within the subvolume. E The integrity of the unit cell structures within the electrode assembly can be maintained by distributing the spacer structures within the electrode layer 116 in a distribution that provides sufficient support to the unit cell structures within the electrode assembly within the volume V of the electrode layer 116. According to one embodiment, the spacer structures are distributed to provide sufficient structural support to avoid excessively large gaps or voids that could lead to collapse or failure of unit cells within the stacked continuum of the electrode assembly. In one embodiment, the population of spacer structures is such that at least one member is positioned within the volume V of the electrode layer. E Within each sub-volume of the electrode assembly having at least 20% of the volume V of the electrode layer, E Within each sub-volume of the electrode assembly, for example, the volume V of the electrode layer E and the like, so that at least 5% of the electrode assembly is located within each sub-volume of the electrode assembly.

[0069] 4A-7C, various embodiments of an electrode assembly unit cell 500 are shown, including a collection of spacer layers. Referring to FIG. 4A, a cross section of the unit cell 500 is shown as taken along the XY plane of the electrode assembly unit cell 500, as shown in the embodiment of FIGS. 3B-3C. In this embodiment, the unit cell has a width W measured between the unit cell portion of the electrode current collector 114 and the unit cell portion of the counter electrode current collector 118 in the stacking direction (parallel to the Y axis). UCThe electrode layer 116 includes an electrode active material layer 125 disposed adjacent to the electrode current collector, and a void 126 between the electrode active material layer 125 and the surface of the separator, and has an electrode layer width W as shown and as discussed elsewhere herein. E is defined between the electrode current collector 114 and the separator, and both the electrode active material layer 125 and the void portion 126 are formed over the width W of the electrode layer 116. E According to one embodiment, the unit cell 500 may be in a pre-formation stage prior to performing a formation process to completely form a secondary battery including the unit cell 500, but the same unit cell 500 in a post-formation stage may include an electrode active material layer 125 that fills a significant portion, or even substantially all, of the void 126. Furthermore, as shown, the cross section is taken with respect to the XY plane at a location in Z where no spacers are present, but a three-dimensional complete unit cell would include spacer structures in other planes along Z. The electrode layer 116 includes first and second end surfaces 121 a, 121 b that have edges of the electrode active material layer 125.

[0070] 4B, a cross section of a unit cell 500 is shown as being taken along the YZ plane of the unit cell 500 of an electrode assembly 106, such as the embodiment shown in FIGS. 3B-3C. In this embodiment, the unit cell has a width W measured between the unit cell portion of the electrode current collector 114 and the unit cell portion of the counter electrode current collector 118 in the stacking direction (parallel to the Y axis). UC The electrode layer 116 includes an electrode active material layer 125 disposed adjacent to the electrode current collector, and a void 126 between the electrode active material layer 125 and the surface of the separator, and has an electrode layer width W as shown and as discussed elsewhere herein. E is defined between the electrode current collector 114 and the separator, and both the electrode active material layer 125 and the void portion 126 are formed over the width W of the electrode layer 116. EAccording to one embodiment, the unit cell 500 may be in a pre-formation stage prior to performing a formation process to fully form a secondary battery including the unit cell 500, but the same unit cell 500 in a post-formation stage may include an electrode active material layer 125 that fills a significant portion of the void 126, or even substantially all of the void 126. Furthermore, as shown, the cross section is taken with respect to the YZ plane at a location in X where no spacers are present, but a three-dimensional complete unit cell may include spacer structures in other planes along Z. The electrode layer 116 includes top and bottom surfaces 119 a, 119 b that have edges of the electrode active material layer 125.

[0071] 5A, a cross section of another embodiment of a unit cell 500 is shown as taken along the YZ plane at a location in Z where the spacer structure 400 is visible. In this embodiment, the unit cell has a width W measured between the unit cell portion of the electrode current collector 114 and the unit cell portion of the counter electrode current collector 118 in the stacking direction (parallel to the Y axis). UC The cross section of the electrode layer 116 includes the electrode active material layer 125 disposed adjacent to the electrode current collector, the spacer structures 400 on either side of the electrode active material layer 125, and the gap 126 between the electrode active material layer 125 and the surface 131a of the separator 130. The width W of the electrode layer E can be defined between the electrode current collector 114 and the separator 130, as shown and discussed elsewhere herein, and the electrode active material layer 125, the spacer structure 400, and the void space 126 are spaced apart by the width W of the electrode layer 116. E According to one embodiment, the unit cell 500 may be in a pre-formation stage prior to performing a formation process to completely form a secondary battery including the unit cell 500, but the same unit cell 500 in a post-formation stage may include an electrode active material layer 125 that fills a significant portion of the void 126, or even substantially all of the void 126. Two spacer structures 400 are disposed on either end of the electrode active material layer 125 and extend a width W from the unit cell portion of the electrode current collector. E, extending along the length dimension L of the electrode layer 116 to the separator 130. Additionally, as shown, the cross section is taken relative to the YX plane at a location in Z where the spacers reside, and the three-dimensional complete unit cell can include additional spacer structures in other planes along Z according to desired spacing characteristics. The electrode layer 116 includes first and second end surfaces 121 a, 121 b, which in the embodiment as shown, include the respective ends of the respective spacer structures in the length dimension L of the electrode layer 116. E 5B illustrates one embodiment of the unit cell of FIG. 5A in a post-formation stage following the formation process, in which electrode active material layer 125 has expanded to at least partially, and even substantially completely, fill void 126.

[0072] 5C shows the unit cell of FIG. 5A in a cross section taken in the YZ plane, at a position in X where the spacer structure 400 can be seen. In this embodiment, the unit cell has a width W measured between the unit cell portion of the electrode current collector 114 and the unit cell portion of the counter electrode current collector 118 in the stacking direction (parallel to the Y axis). UC The cross section of the electrode layer 116 includes the spacer structure 400 and has a width W of the electrode layer, as shown and as discussed elsewhere herein. E is defined between the electrode current collector 114 and the separator, and the spacer structure 400 is spaced apart from the width W of the electrode layer 116. E The electrode layer 116 includes top and bottom surfaces 119a, 119b, which in the illustrated embodiment include the top and bottom ends, respectively, of the spacer structure 400 in the height dimension (parallel to the Z-axis), and define the height H of the electrode layer 116. E According to a further embodiment, a group of spacer structures 400 defines a length L E and / or height H E and / or may include multiple structures 400 arranged along the length L of the electrode layer 116. E and / or height H EThe substrate 400 may include one or more spacer structures 400 extending substantially across the substrate 400 .

[0073] 6 shows yet another embodiment of a unit cell including a spacer structure 400 at a position in Z in a cross section taken in the YX plane, where the spacer structure 400 is visible and located at the periphery of the electrode layer 116 in the length direction and can extend from the inner surface 127 of the electrode active material layer 125. In this embodiment, the unit cell has a width W measured between the unit cell portion of the electrode current collector 114 and the unit cell portion of the counter electrode current collector 118 in the stacking direction (parallel to the Y axis). UC The cross section of the electrode layer 116 includes spacer structures 400 on either side of the electrode active material layer 125, and has a width W of the electrode layer, as shown and as discussed elsewhere herein. E is defined between the electrode current collector 114 and the separator, and the width W of the electrode layer 116 E Included within the electrode active material layer 116 are the electrode active material layer 125, the void 126, and the spacer structure 400. The electrode layer 116 includes first and second end faces 121 a, 121 b, which in the illustrated embodiment include the end faces of the electrode active material layer 125 and the end faces of the spacer structure 400 adjacent in the length dimension (along the X-axis), and the length L of the electrode layer 116 including the spacer structure 400 and the electrode active material layer 116 is E 5A, the spacer structure 400 as shown in FIG. 6 defines a width W of the electrode layer from the interface with the separator. E According to one embodiment, in the pre-formed state, the spacer structures 400 extend from the surface 127 of the electrode active material layer 125 to the surface 131 of the separator layer 130. In the post-formed state, the electrode active material expands to at least partially fill the pre-formed voids 126. In one embodiment, the spacer structures extend from the surface 127 of the electrode active material layer 125 to the surface 131 of the separator layer 130. E According to yet another embodiment, the spacer structure 400 may extend from the surface 115a of the electrode current collector 114 to a width dimension W EAccording to one embodiment, the members of the group of spacer structures may extend at least partially through the electrode active material layer along a width dimension W of the electrode layer between the facing surfaces of the electrode current collector and the separator layer. E Overall (width W E 100%) of the electrode layer width W E According to another embodiment, the median extent of the spacer structures 400 within the electrode layer 116 is greater than or equal to the width W of the electrode layer 116, e.g., as measured from the separator layer 130 toward the electrode current collector 114, or vice versa. E In one embodiment, the median extent of the members of the population of spacer structures in the electrode layer 116 may be less than 60%, less than 50%, less than 40%, less than 25%, and / or less than 15% of the width W of the electrode layer, e.g., as measured from the separator layer 130 to the electrode current collector 114 or vice versa. E According to another embodiment, the population of spacer structures may be at least 2%, at least 3%, and / or at least 5% of the width dimension W of the electrode layer 116. E a spacer structure extending only partially along a width dimension W E The present invention may include a combination of spacer structures extending completely along the length of the substrate (e.g., a combination of the spacer structures shown in Figures 5A and 6). Other suitable spacer structure configurations and arrangements may also be provided.

[0074] 7A-7C illustrate further embodiments of a spacer structure 400 suitable for use with the electrode assembly 106 of the secondary battery 102. In the embodiment illustrated in FIG. 7A, portions of two adjacent unit cells 500a, 500b are shown that share a common electrode current collector 114. In the illustrated embodiment, the electrode current collector 114 includes a first electrode layer 116a disposed on a first side of the electrode current collector (in the first unit cell 500a) and a second electrode layer 116b on an opposing second side of the electrode current collector (in the second unit cell 500b). The first electrode layer 116 includes, for the first unit cell 500a, a first layer 125a of electrode active material layers and a first void 126a between the first layer 125a of electrode active material and the separator 130. The spacer structure 400 extends from the first unit cell portion of the electrode current collector 114 toward the separator in the stacking direction and around the periphery of the first electrode active material layer 125a. The second electrode layer 116b includes, for the second unit cell 500b, a second layer 125b of electrode active material layers and a second void 126b between the second layer 125b of electrode active material and the separator 130, with the spacer structure 400 extending from the second unit cell portion of the electrode current collector 114 toward the separator in the stacking direction and around the periphery of the second electrode active material layer 125b. While the illustrated embodiment shows the electrode assembly 106 before formation having voids 126a, 126b, in embodiments of the electrode assembly after formation, the electrode active material can expand toward the separator and substantially fill the void.

[0075] Similarly, FIG. 7B shows an embodiment in which adjacent unit cells 500a, 500b share a common electrode current collector 114, and spacer structures 400 are provided in the first and second electrode layers 116a, 116b of the adjacent unit cells 500a, 500b. The first electrode layer 116a includes, for the first unit cell 500a, a first layer 125a of electrode active material layers and a first gap 126a between the first layer 125a of electrode active material and the separator 130. The spacer structures 400 extend from a first inner surface 127a of the first electrode active material layer 125 toward the separator in the stacking direction and are located at the periphery of the first inner surface. The second electrode layer 116b includes, for the second unit cell 500b, a second layer 125b of electrode active material layers and a second gap 126b between the second layer 125b of electrode active material and the separator 130. The spacer structure 400 extends from the second inner surface 127b of the second electrode active material layer 125b toward the separator 130 in the stacking direction and is located at the periphery of the second inner surface 127b. According to the illustrated embodiment, the spacer structure 400 is spaced from the separator 130 to the unit cell portion of the electrode current collector 114, and is spaced apart from the width W of the electrode layer 116. E extends only partially along

[0076] According to the embodiment shown in FIGS. 7A and 7B , adjacent first and second unit cells 500 a, 500 b may include spacer structures 400 disposed within the first and second electrode layers 116 a, 116 b, such as adjacent unit cells that share an electrode current collector 114. Similarly, in a wound structure such as that shown in FIGS. 2A and 2B , the spacer structures 400 may be disposed within adjacent windings of the electrode structure in the stacking direction R. However, in other embodiments, the spacer structures 400 may be disposed within alternating unit cells (e.g., every other unit cell) of the stacked sequence along the stacking direction of the electrode assembly, or within certain unit cells and / or only certain unit cells. In yet another embodiment, the spacer structures 400 may be disposed such that they are aligned with each other in the stacking direction. For example, in the embodiment shown in FIG. 7A , the spacer structures 400 are aligned such that the spacers in the first electrode layer 116 a of the first unit cell 500 a are aligned with the spacers in the second electrode layer 116 b of the second unit cell 500 b in the stacking direction (Y direction). Such spacing can be advantageous, for example, to provide a substantially uniform gap within the unit cells along the stacking direction. Similarly, with reference to FIG. 11A , the positions of the spacers may be arranged such that at least some of the spacers are aligned with one another along the stacking direction R. Also, while FIGS. 7A and 7B show the spacers 400 as being located toward the periphery of the electrode layer 116, the spacers may be positioned more centrally within the electrode layer 116 and / or along an inner region at the periphery of the electrode layer 116.

[0077] 7C illustrates yet another embodiment of adjacent first and second unit cells 500a, 500b that include spacer structures 400 disposed within their electrode layers 116. The embodiment of FIG. 7C is similar to the embodiment of FIG. 7A in that the first and second electrode layers 116a, 116b each include an electrode active material layer 125a, 125b around which the spacer structures 400 are located, and the adjacent first and second unit cells 500 share an electrode current collector 400. However, in the embodiment illustrated in FIG. 7C, the spacer structures 400 extend through apertures formed in the electrode current collector 114 shared by both unit cells 500a, 500b, such that the same group of spacer structures 400 extends within both the first and second unit cells 500a, 500b.

[0078] According to yet another embodiment, a population of spacer structures 400 may be provided within the electrode assembly 106 as part of both the electrode structure 110 and the counter electrode structure 112, such as by providing a population of spacer structures 400 not only within one or more electrode layers 116, but also within one or more counter electrode layers 118. For example, a first population of spacer structures 400 may be provided within an electrode layer 116 within the electrode assembly, and a second population of spacer structures 400 may be provided within a counter electrode layer 120 of the electrode assembly, such layers being in the same unit cell and / or in different unit cells within the electrode assembly. According to certain embodiments, the population of spacer structures 400 provided in one or more counter electrode layers 120 can be provided in configurations and / or arrangements corresponding to any of those described elsewhere herein with respect to electrode layer 116, such as in any of Figures 3A-3C, 4A-4C, 5A-5D, 6, 7A-7C, 8A-8H, 9-10, and 11A-11B. That is, the arrangements and / or configurations described elsewhere herein for the population of spacer structures 400 in electrode layer 116 may, in certain embodiments, be suitable for the population of spacer structures in a counter electrode layer, with the counter electrode layer 120, counter electrode active material, and / or counter electrode current collector 118 being substituted for the electrode layer 116, electrode active material, and / or electrode current collector 114 described elsewhere herein.

[0079] In one embodiment, providing first and second populations of spacer structures within both the electrode layer and the counter-electrode layer may be advantageous if both the electrode active material and the counter-electrode active material undergo expansion and / or contraction, such as during the formation process and / or during cycling between charge and discharge states of a secondary battery including the electrode and counter-electrode active materials. According to one embodiment, the population of spacer structures may be provided in a configuration including an electrode active material that expands during charging of the secondary battery and a counter-electrode active material that expands during discharging of the secondary battery, and / or both the electrode active material and the counter-electrode active material may expand during charging of the secondary battery and / or both may expand during discharging of the secondary battery. According to yet another embodiment, one or more of the electrode active material and / or counter-electrode active material may also contract during charging and / or discharging of the secondary battery. In one embodiment, both the electrode active material and the counter-electrode active material (having the same or different magnitudes of expansion) may expand and contract relative to each other during the charging and / or discharging process. In one embodiment, a population of spacer structures can be provided at the interface between an electrode layer and a separator layer, and another population of spacer structures can be provided at the interface between a counter-electrode layer and a separator layer either in the same unit cell and / or in a different unit cell to accommodate expansion (and possibly contraction) that may occur in the electrode and counter-electrode active materials during the formation process and / or during cycling between charge and discharge states of the secondary battery.

[0080] 8A-8H illustrate further embodiments of a population of spacer structures 400 disposed within an electrode layer 116. As shown, the spacer structures 400 can include protrusions 402, which may be formed on a surface of the electrode structure, such as on a surface of the electrode current collector 114 and / or the electrode active material layer 125, and may take various shapes and forms. According to yet another embodiment, the spacer structures 400 can be formed on a surface of one or more of the separator layer 130 and the electrode current collector layer 114, such as in any of the configurations shown in FIGS. 8A-8H, and bonded to form a unit cell 500 that includes the electrode layer during assembly of the electrode assembly. In one embodiment, as shown in FIG. 8A, the spacer structures include a series of raised ridges positioned around the periphery 404 of the electrode layer 116. By providing protrusions and / or ridges around the periphery 400, in certain embodiments, the structure can stabilize the layers around the void so that the separator and electrode layers 116 remain spaced apart from one another, e.g., without the layers substantially bending or deforming into the void. In the embodiment shown in Figure 8B, the group of spacer structures includes a single raised ridge around the periphery 400 of the electrode layer 116.

[0081] 8C, the population of spacer structures 400 may include multiple columns or other raised features distributed across different points on the surface of the electrode layer 116. By distributing the protrusions across the surface, bending and / or deformation of the layer 116 bearing these protrusions is inhibited, and if the protrusions are able to contact adjacent layers (i.e., separator layers 130), separation between these layers can be maintained even under the pressure of the stack of electrode layers when arranged in a stacked sequence.

[0082] Further embodiments are shown in Figures 8D and 8E, which show a population of spacer structures including a series of ridges formed on the surface of the layer and extending diagonally across one or more dimensions of the layer, such as across the height and length of the layer (Figure 8D), as well as a series of cross-shaped protrusions formed around the periphery 404 of the electrode layer 116. Further, Figure 8F shows an embodiment in which the population of spacer structures 400 includes a series of protrusions distributed around the periphery 404 of the electrode layer 116, specifically located at the edge of the electrode layer in the height direction (Z dimension). Figures 8G and 8H show further embodiments of the distribution and configuration of the spacer structures, one in which the spacing between the spacer structures decreases along the height direction (Z dimension) of the electrode layer 116 (Figure 8H) and one in which the spacing between the spacer structures is uniform along the height direction (Z dimension) (Figure 8G).

[0083] According to certain embodiments, the distance between spacer structures may increase and / or decrease along one or more dimensions of the electrode layer 116 and / or between unit cells and / or turns within a wound electrode. For example, with reference to the spirally wound battery embodiment shown in Figures 11A and 11B, in one embodiment, the spacing between spacer structures is determined by the length L of the electrode from the inner region to the outer region of the electrode assembly. E By increasing the spacing along R, the spacer structures in adjacent windings of the electrode assembly can be aligned with one another in the stacking direction R. That is, the spacing between the spacer structures can increase as a function of increasing R, providing the spacer structures are aligned with one another in the stacking direction R. In one embodiment, members of a group of spacer structures 400 are aligned such that a spacer structure 400 disposed in an inner winding 205 a of a unit cell is aligned in the stacking direction with a spacer structure 400 in an outer winding 205 b of the unit cell. FIG. 11C illustrates yet another embodiment of a wound electrode assembly 106 in which a winding 205 includes a straight edge along a winding path 208 of an electrode layer 116.

[0084] According to one embodiment, the electrode assembly 106 including the population of spacers 400 within the electrode layer 116 is suitable for use in a secondary battery that is repeatedly cycled between a charged and discharged state. According to certain embodiments, the electrode assembly including the population of spacers may be in a pre-formation stage, prior to undergoing a formation process, as discussed elsewhere herein. That is, the electrode assembly 106 may be suitable for incorporation into a storage device, such as a secondary battery, and may undergo a formation process. Embodiments herein may also contemplate the electrode assembly 106 in a post-formation stage, such as when the electrode assembly forms part of a secondary battery or other storage device that has undergone a formation process.

[0085] According to one embodiment, a method for forming a secondary battery that is cycled between a charged state and a discharged state includes performing a forming process that involves providing an electrode assembly, carrier ions, and a non-aqueous electrolyte solution within a battery housing, and charging the secondary battery from a discharged state to a charged state. In one embodiment, the forming process can be performed to increase the volume of the solid active electrode material in the electrode layer such that the post-formation volume is at least 3%, at least 5%, at least 10%, at least 25%, at least 50%, at least 75%, and / or at least 100% greater than the first volume of the solid active electrode material in the electrode layer. Furthermore, while the increase in volume of the solid active electrode material can occur, the width W of the unit cell before formation can be increased. UC The width of the unit cell shown after formation, W, compared to UC and / or the change in the width W of the unit cell both before and after formation is less than 1%, less than 0.5%, less than 0.25%, and / or less than 0.1% in some embodiments. UC may be substantially the same, so that the width of the unit cell 500 does not change substantially during the formation process.

[0086] According to certain embodiments, the formation process may include at least one initial charge cycle of the secondary battery 102, which may be performed under carefully controlled conditions, including one or more of current, temperature, and duration, to promote the formation of desired structures and contacts between components of the secondary battery 102, such as the desired structures and contacts between structures within the unit cells 500. Generally, the formation process may include one or more initial charge steps performed under conditions that rearrange and / or optimize the internal structure and morphology so that the secondary battery can be charged to its rated capacity. Depending on the particular battery structure and composition, the formation process may include only a single initial charge cycle, or may include multiple charge cycles, as described elsewhere herein, and may be performed as a final stage during secondary battery fabrication to bring the secondary battery 102 to its full power and / or capacity.

[0087] In one embodiment, referring to FIG. 3C , an electrode constraint set 602 is provided to constrain growth in the stacking direction of the electrode assembly and / or maintain alignment of a group of unit cells within the electrode assembly during the formation process. For example, the electrode constraint set 602 can include first and second constraint members 600 a, 600 b, which are spaced apart along the stacking direction (the Y direction in FIG. 3C ) and can maintain alignment of structures within the electrode assembly in the stacking direction during, and optionally after, the formation process. In one embodiment, growth and / or swelling of the electrode active material within the electrode layer 116 can exert pressure in the stacking direction and / or cause the unit cells 500 to move out of alignment with one another. Accordingly, by providing the electrode constraint set 602, alignment of structures within each unit cell can be maintained such that voids 126 within the unit cells can be effectively utilized to allow expansion of the electrode active material therein.

[0088] In one embodiment, the electrode constraint set 602 includes first and second constraint members 600a, 600b spaced apart from each other along the stacking direction, as shown in FIG. 3C . In another embodiment, the electrode constraint set includes first and second constraint members 600a, 600b spaced apart from each other along another direction perpendicular to the stacking direction, e.g., along one or more of the X and Z directions. A combination of constraints along the stacking direction, in addition to one or more constraints that constrain within one or more of the X and Z directions and / or along a direction perpendicular to the stacking direction, may also be provided. According to one embodiment of a prismatic electrode assembly, the first and second constraint members may be spaced apart from each other along the Y direction, which corresponds to the stacking direction, as shown in FIG. 3C . According to another embodiment of a wound electrode assembly, the constraint set 602 may be configured to constrain along the stacking direction R, such as by providing a cylindrical constraint member and / or one or more segments of a cylindrical constraint extending around the periphery of the wound electrode assembly. For example, the restraint set for the wound electrode assembly may be a can or other housing 104 for the electrode assembly.

[0089] In one embodiment, the electrode constraint set is provided within the battery housing 104 (not shown). In another embodiment, the electrode constraint set 602 is provided outside the battery housing (shown in FIG. 3C). The battery housing 104 may be a sealed housing that seals the electrolyte used in the secondary battery therein. In a further embodiment, the electrode constraint set 602 may be provided before and / or during the formation process and removed from the electrode assembly 106 after formation. According to yet another embodiment, the electrode constraint set 602 may be provided before and / or during the formation process and retained as part of the secondary battery after formation, e.g., to resist growth and / or swelling of the electrode active material during normal cycling of the secondary battery. Without limitation, embodiments of suitable electrode restraints that can be provided to restrain the electrode assembly 106 before, during, and / or after the formation process are described, for example, in U.S. Pat. No. 10,283,807 to Busacca et al., issued May 7, 2019, and U.S. Pat. No. 10,177,400 to Busacca et al., issued January 8, 2019, both of which are incorporated by reference in their entireties herein.

[0090] According to one embodiment, at least a portion, or even entirely all, of the population of spacer structures 400 can be absent after the formation process, for example, if the spacer structures 400 can be incorporated into the electrode active material during the post-formation stage. Furthermore, according to certain embodiments, the population of spacer structures can be mixed into the electrode active material layer 125 during the post-formation stage, for example, such that the electrode active material layer 125 occupies substantially the entire volume of the electrode layer after formation. For example, if the spacer structures include lithium spacer structures used in a secondary battery including a lithium electrode during the pre-formation stage, the interface between the lithium spacer structures and the remainder of the electrode layer may be indistinguishable during the post-formation stage due to the growth of the lithium-containing electrode active material during the formation process. According to yet another embodiment, the population of spacers can chemically react after the electrolyte is filled into the electrode assembly prior to formation, such that at least a portion and / or all of the population of spacers becomes indistinguishable after formation. According to yet another embodiment, at least some and / or all of the spacer population may be removed after assembly of the electrode assembly 106 (e.g., after stacking of the unit cells 500), and either before, during, or after the formation process, for example, if another method of maintaining the voids 126 within the unit cells 500 is provided.

[0091] According to various embodiments, the spacer structure 400 may be formed by a variety of different methods. For example, in one embodiment, the spacer structure 400 can be formed by printing a spacer material onto the electrode structure 110 (e.g., the electrode current collector and / or electrode active material layer) and / or the separator layer, such as by screen printing, stencil printing, inkjet printing, weight printing, and other methods. According to yet another embodiment, the spacer structure can be fabricated by a vapor deposition method using a shadow mask. According to yet another embodiment, the spacer structure can be fabricated by mechanically interfacing pins containing the spacer material into the electrode structure 110 and / or the separator layer 130 with an interference fit. According to yet another embodiment, the spacer structure can be fabricated by co-molding with one or more portions of the separator layer 130 and / or the electrode structure 110. According to yet another embodiment, the spacer structure can be fabricated by disposing an open mesh between the electrode structure 110 and the separator 130 during assembly of the unit cell 500. According to yet another embodiment, the spacer structures can be fabricated by laying wire on top of the electrode structure 110 using glue and pressing it to a desired height above the electrode structure. According to certain embodiments, the population of spacer structures 400 can be deposited or otherwise formed simultaneously with the electrode active material of the electrode active material layer 125. For example, if the electrode active material is deposited or otherwise formed on the surface of the electrode current collector 114, the population of spacer material can likewise be deposited or otherwise formed as part of the formation process of this electrode active material layer. According to yet another embodiment, the population of spacer structures can be deposited before and / or after the electrode active material is already deposited or otherwise formed on the electrode current collector 114. According to yet another embodiment, the population of spacer structures can be at least partially deposited and / or formed during the deposition / formation process of the electrode active material layer and can be completed after the formation of the electrode active material layer is complete.According to another embodiment, the population of spacer structures can be formed as an additive or subtractive process before and / or after the electrode active material layer is formed. Other methods of fabricating the spacer structures and / or combinations of these fabrication methods may also be provided.

[0092] Furthermore, as used herein, for each embodiment in which the term "electrode" is used to describe a material or structure, such as an "electrode structure" or "electrode active material," it is understood that such structure and / or materials can, in certain embodiments, correspond to that of an "negative electrode," such as an "negative electrode structure" or "negative electrode active material." Similarly, as used herein, for each embodiment in which the term "counter electrode" is used to describe a material or structure, such as a "counter electrode structure" or "counter electrode active material," it is understood that such structure and / or materials can, in certain embodiments, correspond to that of a "positive electrode," such as a "positive electrode structure" or "positive electrode active material." That is, where appropriate, any embodiment described with respect to an electrode and / or counter electrode may correspond to the same embodiment in which the electrode and / or counter electrode, respectively, includes their corresponding structures and materials, specifically, the negative electrode and / or positive electrode.

[0093] Other Battery Components The mass members of the electrode 110 and counter electrode 112 comprise electroactive materials capable of absorbing and releasing carrier ions, such as lithium, sodium, potassium, calcium, magnesium, or aluminum ions. In some embodiments, the mass members of the electrode structure 110 comprise anode active electroactive material (sometimes referred to as a negative electrode), and the mass members of the counter electrode structure 112 comprise cathode active electroactive material (sometimes referred to as a positive electrode). In other embodiments, the mass members of the electrode structure 110 comprise cathode active electroactive material, and the mass members of the counter electrode structure 112 comprise anode active electroactive material. For example, the negative electrode active material may be, for example, a particle agglomerate electrode, an electrode active material formed from particulate material, such as by forming a slurry of particulate material and casting it into a layer, or a monolithic electrode.

[0094] Exemplary anode active electroactive materials include carbon materials such as graphite and soft or hard carbon, or any of a range of metals, semi-metals, alloys, oxides, and compounds capable of forming alloys with lithium. Specific examples of metals or semi-metals that can comprise the anode material include graphite, tin, lead, magnesium, aluminum, boron, gallium, silicon, Si / C composites, Si / graphite blends, SiOx, porous Si, intermetallic Si alloys, indium, zirconium, germanium, bismuth, cadmium, antimony, silver, zinc, arsenic, hafnium, yttrium, lithium, sodium, graphite, carbon, lithium titanate, palladium, and mixtures thereof. In one exemplary embodiment, the anode active material includes aluminum, tin, or silicon, or an oxide thereof, a nitride thereof, a fluoride thereof, or another alloy thereof. In another exemplary embodiment, the anode active material includes silicon, silicon oxide, or an alloy thereof.

[0095] In yet another embodiment, the anode active material can include lithium metal, lithium alloys, carbon, petroleum coke, activated carbon, graphite, silicon compounds, tin compounds, and alloys thereof. In one embodiment, the anode active material can include carbon, such as non-graphitizable carbon, graphitic carbon; Li x Fe2O3(0≦x≦1), Li x WO2(0≦x≦1), Sn x Me 1-x Me' y O z(Me: Mn, Fe, Pb, Ge; Me’: Al, B, P, Si, elements in Groups 1, 2, and 3 of the periodic table, halogens; 0 < x ≤ 1; 1 ≤ y ≤ 3; 1 ≤ z ≤ 8), etc. metal complex oxides; lithium metal; lithium alloys; silicon-based alloys; tin-based alloys; metal oxides such as SnO, SnO2, PbO, PbO2, Pb2O3, Pb3O4, Sb2O3, Sb2O4, Sb2O5, GeO, GeO2, Bi2O3, Bi2O4, Bi2O5; conductive polymers such as polyacetylene; Li-Co-Ni-based materials, etc. are included. In one embodiment, the anode active material can include a carbon-based active material including crystalline graphite such as natural graphite and synthetic graphite, and amorphous carbon such as soft carbon and hard carbon. Other examples of carbon materials suitable for the anode active material can include high-temperature sintered carbon such as graphite, kish graphite, pyrolytic carbon, mesophase pitch-based carbon fibers, mesocarbon microbeads, mesophase pitch, graphitized carbon fibers, and coke derived from petroleum or coal tar pitch. In one embodiment, the negative electrode active material may include tin oxide, titanium nitrate, and silicon. In another embodiment, the negative electrode can include a lithium metal such as a lithium metal film, or a lithium alloy such as an alloy of lithium and one or more metals selected from the group consisting of Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Ba, Ra, Al, and Sn. In yet another embodiment, the anode active material is a metal compound that can alloy with and / or intercalate with lithium, such as Si, Al, C, Pt, Sn, Pb, Ir, Ni, Cu, Ti, Na, K, Rb, Cs, Fr, Be, Ca, Sr, Sb, Ba, Ra, Ge, Zn, Bi, In, Mg, Ga, Cd, Si alloy, Sn alloy, Al alloy, etc.; SiO v(0 < v < 2), metal oxides such as SnO2, vanadium oxide or lithium vanadium oxide that can be doped and undoped with lithium ions; and composite materials including metal compounds and carbon materials such as Si-C composite materials or Sn-C composite materials can be included. For example, in one embodiment, the material that can alloy / intercalate with lithium can be a metal such as lithium, indium, tin, aluminum, or silicon, or their alloys; transition metal oxides such as Li4 / 3Ti5 / 3O4 or SnO; and carbonaceous materials such as artificial graphite, graphite carbon fiber, resin-fired carbon, pyrolytic vapor-grown carbon, coke, mesocarbon microbeads ("MCMB"), furfuryl alcohol resin-fired carbon, polyacene, pitch-based carbon fiber, vapor-grown carbon fiber, or natural graphite. In yet another embodiment, the negative electrode active material can include a composition suitable for carrier ions such as sodium or magnesium. For example, in one embodiment, the negative electrode active material is a layered carbonaceous material, and the chemical formula deposited between the layers of the layered carbonaceous material, Na x Sn y-z M z of the composition can be included, where M is Ti, K, Ge, P, or a combination thereof, 0 < x ≦ 15, 1 ≦ y ≦ 5, and 0 ≦ z ≦ 1.

[0096] In one embodiment, the negative electrode active material may further include a conductive material and / or conductive additive (e.g., carbon-based materials, carbon black, graphite, graphene, activated carbon, carbon fiber, carbon black such as acetylene black, ketjen black, channel black, furnace black, lamp black, and thermal black), conductive fiber (e.g., carbon fiber, metal fiber), conductive tube (e.g., carbon nanotube), metal powder (e.g., fluorocarbon powder, aluminum powder, nickel powder), conductive whisker (e.g., zinc oxide, potassium titanate), conductive metal oxide (e.g., titanium oxide), or conductive material (e.g., polyphenylene derivative). Furthermore, metal fiber such as metal mesh; metal powder such as copper, silver, nickel, and aluminum; or organic conductive material such as polyphenylene derivative may also be used. In yet another embodiment, a binder such as one or more of polyethylene, polyethylene oxide, polypropylene, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), styrene-butadiene rubber, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-chlorotrifluoroethylene copolymer, ethylene-tetrafluoroethylene copolymer, polychlorotrifluoroethylene, vinylidene fluoride-pentafluoropropylene copolymer, propylene-tetrafluoroethylene copolymer, ethylene-chlorotrifluoroethylene copolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer, vinylidene fluoride-perfluoromethyl vinyl ether-tetrafluoroethylene copolymer, ethylene-acrylic acid copolymer, and the like may be provided and may be used either alone or as a mixture.

[0097] Exemplary cathode active materials include any of a wide range of cathode active materials. For example, in the case of lithium-ion batteries, the cathode active material may include a cathode material selected from transition metal oxides, transition metal sulfides, transition metal nitrides, lithium transition metal oxides, lithium transition metal sulfides, and lithium transition metal nitrides, which may be selectively used. The transition metal elements of these transition metal oxides, transition metal sulfides, and transition metal nitrides may include metal elements having a d-shell or an f-shell. Specific examples of such metal elements include Sc, Y, lanthanides, actinides, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Tc, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pb, Pt, Cu, Ag, and Au. Additional cathode active materials include LiCoO2, LiNi 0.5 Mn 1.5 O4, Li(Ni x Co y Al z )O2, LiFePO4, Li2MnO4, V2O5, oxymolybdenum sulfides, phosphates, silicates, vanadates, sulfur, sulfur compounds, oxygen (air), Li(Ni x Mn y Co z )O2, and combinations thereof. Additionally, the compounds of the cathode active material layer can include lithium-containing compounds, which can further include metal oxides or metal phosphates, such as compounds containing lithium, cobalt, and oxygen (e.g., LiCoO2), compounds containing lithium, manganese, and oxygen (e.g., LiMn2O4), and compounds containing lithium iron phosphate (e.g., LiFePO4). In one embodiment, the cathode active material includes at least one of lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium iron phosphate, or a composite oxide formed from a combination of the foregoing oxides. In another embodiment, the cathode active material includes lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), or the like, or substituted compounds with one or more transition metals; Li 1+x Mn 2-xO4 (where x is from 0 to 0.33), lithium manganese oxides such as LiMnO3, LiMn2O3, LiMnO2; lithium copper oxide (Li2CuO2); vanadium oxides such as LiV3O8, LiFe3O4, V2O5, Cu2V2O7; LiNi 1-x M x Ni-site type lithium nickel oxide represented by the chemical formula of M x O2 (where M = Co, Mn, Al, Cu, Fe, Mg, B or Ga, and x = 0.01 to 0.3); LiMn 2-x M x Lithium manganese composite oxides represented by the chemical formula of M x O2 (where M = Co, Ni, Fe, Cr, Zn or Ta, and x = 0.01 to 0.1) or Li2Mn3MO8 (where M = Fe, Co, Ni, Cu or Zn); LiMn2O4 in which part of Li is substituted by alkaline earth metal ions; disulfide compounds; one or more of Fe2(MoO4)3, etc. can be included. In one embodiment, the cathode active material is of formula 2: Li 1+a Fe 1-x M’ x (PO 4-b )X b Lithium metal phosphate having an olivine crystal structure, where M’ is at least one selected from Al, Mg, Ni, Co, Mn, Ti, Ga, Cu, V, Nb, Zr, Ce, In, Zn, and Y, X is at least one selected from F, S, and N, -0.5 ≦ a ≦ +0.5, 0 ≦ x ≦ 0.5, and 0 ≦ b ≦ 0.1, for example, at least one of LiFePO4, Li(Fe,Mn)PO4, Li(Fe,Co)PO4, Li(Fe,Ni)PO4, etc. In one embodiment, the cathode active material is LiCoO2, LiNiO2, LiMnO2, LiMn2O4, LiNi 1-y Co y O2, LiCo 1-y Mn y O2, LiNi 1-y Mn y O2 (0 ≦ y ≦ 1), Li(Ni a Co b Mn c )O4 (0 < a < 2, 0 < b < 2, 0 < c < 2, and a + b + c = 2), LiMn 2-z Niz O4, LiMn 2-z Co z It contains at least one of O4(0 < z < 2), LiCoPO4, and LiFePO4, or a mixture of two or more of them.

[0098] In yet another embodiment, the cathode active material can include elemental sulfur (S8), sulfur-based compounds, or mixtures thereof. Sulfur-based compounds specifically include Li2S n (n ≧ 1), organic sulfur compounds, carbon-sulfur polymers ((C2S x ) n : x = 2.5 to 50, n ≧ 2), etc. In yet another embodiment, the cathode active material can include oxides of lithium and zirconium.

[0099] In yet another embodiment, the cathode active material can include at least one composite oxide of lithium and a metal such as cobalt, manganese, nickel, or combinations thereof, and these can be used. Examples of them are Li a A 1-b M b D2 (where 0.90 ≦ a ≦ 1 and 0 ≦ b ≦ 0.5); Li a E 1-b M b O 2-c D c (where 0.90 ≦ a ≦ 1, 0 ≦ b ≦ 0.5, and 0 ≦ c ≦ 0.05); LiE 2-b M b O 4-c D c (where 0 ≦ b ≦ 0.5 and 0 ≦ c ≦ 0.05); Li a Ni 1-b-c Co b M c D a (where 0.90 ≦ a ≦ 1, 0 ≦ b ≦ 0.5, 0 ≦ c ≦ 0.05, and 0 < a ≦ 2); Li a Ni 1-b-c Co b M c O 2-a X a (where 0.90 ≦ a ≦ 1, 0 ≦ b ≦ 0.5, 0 ≦ c ≦ 0.05, and 0 < a < 2); Lia Ni 1-b-c Co b M c O 2-a X2 (wherein 0.90≦a≦1, 0≦b≦0.5, 0≦c≦0.05, and 0 <a<2);Li a Ni 1-b-c Mn b M c D a (Wherein, 0.90≦a≦1, 0≦b≦0.5, 0≦c≦0.05, and 0 <a≦2);Li a Ni 1-b-c Mn b M c O 2-a X a (Wherein, 0.90≦a≦1, 0≦b≦0.5, 0≦c≦0.05, and 0 <a<2);Li a Ni 1-b-c Mn b M c O 2-a X2 (wherein 0.90≦a≦1, 0≦b≦0.5, 0≦c≦0.05, and 0 <a<2);Li a Ni b E c G d O2 (wherein 0.90≦a≦1, 0≦b≦0.9, 0≦c≦0.5, and 0.001≦d≦0.1); Li a Ni b Co c Mn d GeO2 (wherein 0.90≦a≦1, 0≦b≦0.9, 0≦c≦0.5, 0≦d≦0.5, and 0.001≦e≦0.1); Li a NiG b O2 (wherein 0.90≦a≦1 and 0.001≦b≦0.1); Li a CoG b O2 (wherein 0.90≦a≦1 and 0.001≦b≦0.1); Li a MnG b O2 (wherein 0.90≦a≦1 and 0.001≦b≦0.1); Li a Mn2G b O4 (wherein 0.90≦a≦1 and 0.001≦b≦0.1); QO2; QS2; LiQS2; V2O5; LiV2O5; LiX'O2; LiNiVO4; Li (3-f) J2(PO4)3(0≦f≦2);Li(3-f) Fe2(PO4)3 (0≦f≦2); and LiFePO4. In the above formula, A is Ni, Co, Mn, or a combination thereof; M is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element, or a combination thereof; D is O, F, S, P, or a combination thereof; E is Co, Mn, or a combination thereof; X is F, S, P, or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; Q is Ti, Mo, Mn, or a combination thereof; X' is Cr, V, Fe, Sc, Y, or a combination thereof; and J is V, Cr, Mn, Co, Ni, Cu, or a combination thereof. For example, LiCoO2, LiMn x O 2x (x=1 or 2), LiNi 1-x Mn x O 2x (0 <x<1)、LiNi 1-x-y Co x Mn y O2 (0≦x≦0.5, 0≦y≦0.5), or FePO4 can be used. In one embodiment, the cathode active material includes at least one of a lithium compound such as lithium cobalt oxide, lithium nickel oxide, lithium nickel cobalt oxide, lithium nickel cobalt aluminum oxide, lithium nickel cobalt manganese oxide, lithium manganese oxide, or lithium iron phosphate; nickel sulfide; copper sulfide; sulfur; iron oxide; or vanadium oxide.

[0100] In one embodiment, the cathode active material is a sodium-containing material, for example, a material having the formula NaM, such as NaFeO, NaMnO, NaNiO, or NaCoO. 1 a Oxide; or formula NaMn 1-a M 1 a O2, wherein M 1 is at least one transition metal element, and 0≦a<1. A typical positive electrode active material is Na[Ni1 / 2 Mn 1 / 2 ]O2, Na 2 / 3 [Fe 1 / 2 Mn 1 / 2 ]O2 etc.;Na 0.44 Mn 1-a M 1 a Oxide represented by O2, Na 0.7 Mn 1-a M 1 a O 2.05 an oxide represented by the formula M 1 is at least one transition metal element, 0≦a<1);Na b M 2 c Si 12 O 30 By Na6Fe2Si 12 O 30 or Na2Fe5Si 12 O (wherein M 2 is at least one transition metal element, 2≦b≦6, and 2≦c≦5); Na2Fe2Si6O 18 or Na2MnFeSi6O 18 Na etc. d M 3 e SiO 18 (wherein, M 3 is at least one transition metal element, 3≦d≦6, and 1≦e≦2); Na, such as Na2FeSiO6 f M 4 g Oxide represented by Si2O6 (wherein M 4 is at least one element selected from transition metal elements, magnesium (Mg), and aluminum (Al), where 1≦f≦2 and 1≦g≦2; phosphates such as NaFePO4, Na3Fe2(PO4)3, Na3V2(PO4)3, Na4Co3(PO4)2P2O7; borates such as NaFeBO4 or Na3Fe2(BO4)3; Na such as Na3FeF6 or Na2MnF6 h M 5 Fluoride represented by F6 (wherein, M 5is at least one transition metal element, 2≦h≦3), and includes fluorophosphates such as Na3V2(PO4)2F3 and Na3V2(PO4)2FO2. The positive electrode active material is not limited to those mentioned above, and any suitable positive electrode active material used in the art can be used. In one embodiment, the positive electrode active material is preferably NaMnO2, Na[Ni 1 / 2 Mn 1 / 2 ]O2 and Na 2 / 3 [Fe 1 / 2 Mns 1 / 2 ]O2, phosphate cathodes such as Na3V2(PO4)3 and Na4Co3(PO4)2P2O7, or fluorophosphate cathodes such as Na3V2(PO4)2F3 and Na3V2(PO4)2FO2.

[0101] In yet another embodiment, the cathode active material can further include one or more conductive additives and / or binders, which can be, for example, any of the conductive additives and / or binders described for the anode active material herein.

[0102] In one embodiment, the electrode current collector 114 can include a suitable conductive material, such as a metal material. The electrode current collector 114 can be a negative electrode current collector and / or a positive electrode current collector according to embodiments herein. According to one embodiment, the electrode current collector is a negative electrode current collector. In one embodiment, the electrode current collector can include at least one of copper, nickel, aluminum, stainless steel, titanium, palladium, calcined carbon, calcined carbon, indium, iron, magnesium, cobalt, germanium, lithium, a copper or stainless steel surface treatment material (including carbon, nickel, titanium, and silver), an aluminum-cadmium alloy, and / or other alloys thereof. As another example, in one embodiment, the electrode current collector can include at least one of copper, stainless steel, aluminum, nickel, titanium, calcined carbon, a copper or stainless steel surface treatment material (including carbon, nickel, titanium, and silver), an aluminum-cadmium alloy, and / or other alloys thereof. In one embodiment, the electrode current collector can include at least one of copper and stainless steel.

[0103] In one embodiment, the counter electrode current collector 118 can comprise a suitable conductive material, such as a metallic material. The counter electrode current collector 118 can be a negative electrode current collector and / or may be a positive electrode current collector according to embodiments herein. According to one embodiment, the counter electrode current collector is a positive electrode current collector. In one embodiment, the counter electrode current collector comprises at least one of stainless steel, aluminum, nickel, titanium, calcined carbon, sintered carbon, a surface treatment material of aluminum or stainless steel (including carbon, nickel, titanium, silver), and / or an alloy thereof. In one embodiment, the counter electrode current collector comprises aluminum.

[0104] In one embodiment, the anode active material is microstructured to provide a significant void volume fraction to accommodate volume expansion and contraction when lithium ions (or other carrier ions) are incorporated into or desorbed from the anode active material during charge and discharge processes. Generally, the void volume fraction of the anode active material is at least 0.1. However, typically, the void volume fraction of the anode active material is 0.8 or less. For example, in one embodiment, the void volume fraction of the anode active material is about 0.15 to about 0.75. By way of further example, in one embodiment, the void volume fraction of the anode active material is about 0.2 to about 0.7. By way of further example, in one embodiment, the void volume fraction of the anode active material is about 0.25 to about 0.6.

[0105] In one embodiment, the anode active material comprises porous aluminum, tin, or silicon, or alloys thereof, such as, for example, in the form of an electrode active layer 125 comprising porous anode active material. The porous silicon layer may be formed, for example, by anodic oxidation, by etching (e.g., by depositing a noble metal such as gold, platinum, silver, or gold / palladium on the surface of single-crystal silicon and etching the surface with a mixture of hydrofluoric acid and hydrogen peroxide), or by other methods known in the art, such as patterned chemical etching. Furthermore, the porous anode active material generally has a porosity of at least about 0.1, but less than 0.8, and a thickness of about 1 to about 100 micrometers. For example, in one embodiment, the electrode active material layer 125 comprises an anode active material comprising porous silicon and has a thickness of about 5 to about 100 micrometers (W E ) and has a porosity of about 0.15 to about 0.75. By way of further example, in one embodiment, electrode active material layer 125 comprises an anode active material comprising porous silicon and has a thickness (W) of about 10 to about 80 micrometers. E ) and has a porosity of about 0.15 to about 0.7. By way of further example, in one such embodiment, electrode active material layer 125 comprises porous silicon and has a thickness (W E) and has a porosity of about 0.25 to about 0.6. By way of further example, in one embodiment, electrode active material layer 125 comprises a porous silicon alloy (such as nickel silicide) and has a thickness (W E ) and has a porosity of about 0.15 to about 0.75.

[0106] The length (L E ) will vary depending on the energy storage device and its intended use, however, in one embodiment, the members of the group have a length (L) in the range of about 5 mm to about 500 mm. E For example, in one such embodiment, members of the electrode layer population may have a length (L) of about 10 mm to about 250 mm. E By way of further example, in one such embodiment, the members of the population have a length (L E By way of further example, in one embodiment corresponding to a wound electrode assembly, the members of the group have a length (L ) of at least 50 cm, such as at least 75 cm, or even at least 90 cm. E ) and can have a length of at least about 10 meters, or even at least 100 meters. Thus, by way of example, in one embodiment of a wound electrode assembly, the members of the group have a length L in the range of about 50 cm to about 800 meters, e.g., 75 cm to about 500 meters, or even about 75 cm to about 1 meter. E may have

[0107] The width (W E ) also varies depending on the energy storage device and its intended use. In one embodiment, each member of the population of electrode layers 116 has a width (W) in the range of about 0.01 mm to 2.5 mm. E For example, in one embodiment, each member of the cluster may have a width (W E ) is in the range of about 0.025 mm to about 2 mm. By way of further example, in one embodiment, the width (W E ) is in the range of about 0.05 mm to about 1 mm.

[0108] The height (H E ) also varies depending on the energy storage device and its intended use, however, in one embodiment, members of the population of electrode layers 116 have a height (H E For example, in one embodiment, each member of the cluster may have a height (H E ) is in the range of about 0.05 mm to about 5 mm. By way of further example, in one embodiment, the height (H E ) is in the range of about 0.1 mm to about 1 mm. By way of further example, in one embodiment of a wound electrode assembly, the height (HE) of each member of the group is in the range of about 10 mm to about 500 mm, e.g., in the range of about 25 mm to about 100 mm, including the range of 30 mm to 90 mm, and even in the range of 50 mm to 500 mm, such as in the range of 100 mm to 400 mm.

[0109] In one embodiment, the members of the group of electrode layers 116 have a width (W E ) and its height (H E ) E For example, in one embodiment, L E and W E and H E and each of the electrode layers 116 is at least 5:1 (i.e., L E and W E and L are at least 5:1 in ratio, respectively. E and H E and the ratio of L to L is at least 5:1, respectively. E and W E and H E and each of which is at least 10:1. By way of further example, in one embodiment, L E and W E and H E is at least 15:1. By way of further example, in one embodiment, for each member of the population, E and W E and H EThe ratio of each of these is at least 20:1.

[0110] In one embodiment, the height (H E ) and width (W E ) is at least 0.4:1, respectively. For example, in one embodiment, E and W E and H are at least 2:1, respectively, for each member of the population. E and W E and H are in a ratio of at least 10:1, respectively. E and W E and H are in a ratio of at least 20:1, respectively. E and W E The ratio of H to H is generally less than 1,000:1, respectively. E and W E and H are each less than 500:1. E and W E and H are each less than 100:1. E and W E and H are each less than 10:1. E and W E and the ratio of is in the range of about 2:1 to about 100:1, respectively, for each member of the population.

[0111] The width (W CE ) also varies depending on the energy storage device and its intended use. In one embodiment, members of the counter electrode layer population have a width (W) in the range of about 0.01 mm to 2.5 mm. CE For example, in one embodiment, each member of the cluster may have a width (W CE ) is in the range of about 0.025 mm to about 2 mm. By way of further example, in one embodiment, the width (W CE ) is in the range of about 0.05 mm to about 1 mm.

[0112] The height (H CE ) also varies depending on the energy storage device and its intended use. In one embodiment, members of the counter electrode layer 120 population have a height (H) in the range of about 0.05 mm to about 10 mm. CE For example, in one embodiment, each member of the cluster may have a height (H CE ) is in the range of about 0.05 mm to about 5 mm. By way of further example, in one embodiment, the height (H CE ) is in the range of about 0.1 mm to about 1 mm.

[0113] In one embodiment, each member of the population of counter electrode layers 120 has a width (W CE ) and its height (H CE ) CE For example, in one embodiment, L CE and W CE and H CE The ratio of each of the groups to each of the groups is at least 5:1 (i.e., L CE and W CE and L are at least 5:1 in ratio, respectively. CE and H CE and the ratio of L to L is at least 5:1, respectively. CE and W CE and H CE is at least 10:1 for each member of the population. CE and W CE and H CE and each of the following is at least 15:1 for each member of the population. CE and W CE and H CE is at least 20:1 for each member of the population.

[0114] In one embodiment, the height (H CE ) and width (W CE) is at least 0.4:1, respectively. For example, in one embodiment, CE and W CE and the ratio is at least 2:1, respectively, for each member of the population of counter electrode layers 120. By way of further example, in one embodiment, H CE and W CE and H are at least 10:1, respectively, for each member of the population. CE and W CE and H are at least 20:1, respectively, for each member of the population. CE and W CE The ratio of H to H is generally less than 1,000:1 for each member of the population. CE and W CE and the ratio of H to H is less than 500:1, respectively, for each member of the population. CE and W CE and H are each less than 100:1. CE and W CE and H are each less than 10:1. CE and W CE and the ratio of is in the range of about 2:1 to about 100:1, respectively, for each member of the population.

[0115] According to one embodiment, one or more of the electrode current collector and the counter electrode current collector may comprise a metal such as aluminum, carbon, copper, chromium, gold, nickel, NiP, palladium, platinum, rhodium, ruthenium, an alloy of silicon and nickel, titanium, or a combination thereof (see, A. H. Whitehead and M. Schreiber, "Current collectors for positive electrodes of lithium-based batteries," Journal of the Electrochemical Society, 152(11) A2105-A2113 (2005)). By way of further example, in one embodiment, the electrode current collector comprises gold aluminum. By way of further example, in one embodiment, the counter electrode current collector comprises copper or an alloy thereof.

[0116] The electrically insulating separator layer 130 may electrically insulate each member of the population of electrode assemblies 110 from each member of the population of counter-electrode assemblies 112. The electrically insulating separator layer 130 may include a microporous separator material that can be permeated with a non-aqueous electrolyte. For example, in one embodiment, the microporous separator material includes pores having a diameter of at least 50 Å, more typically in the range of about 2,500 Å, and a porosity in the range of about 25% to about 75%, more typically in the range of about 35-55%. Furthermore, the microporous separator material may be permeated with a non-aqueous electrolyte to allow conduction of carrier ions between adjacent members of the population of electrode and counter-electrodes. In certain embodiments, for example, disregarding the porosity of the microporous separator material, at least 70 vol% of the electrically insulating separator material between a member of the population of electrode structures 110 and the nearest member(s) of the population of counter-electrode structures 112 (i.e., "adjacent pairs" and / or members of the same unit cell 500) is a microporous separator material for ion exchange during a charge or discharge cycle. In other words, in one embodiment, the microporous separator material comprises at least 70 vol%, at least 80 vol%, at least 85 vol%, at least 90 vol%, at least 95 vol%, and / or at least 99 vol% of electrically insulating material between a member of the population of electrode structures 110 and the nearest member of the population of counter-electrode structures 112.

[0117] In one embodiment, the microporous separator material includes a particulate material and a binder and has a porosity of at least about 20 vol.%. The pores of the microporous separator material have a diameter of at least 50 Å, typically in the range of about 250-2,500 Å. The microporous separator material typically has a porosity of less than about 75%. In one embodiment, the microporous separator material has a porosity of at least about 25 vol.%. In one embodiment, the microporous separator material has a porosity of about 35-55%.

[0118] Binders for microporous separator materials may be selected from a wide range of inorganic or polymeric materials. For example, in one embodiment, the binder is an organic material selected from the group consisting of silicates, phosphates, aluminates, aluminosilicates, and hydroxides such as magnesium hydroxide and calcium hydroxide. For example, in one embodiment, the binder is a fluoropolymer derived from monomers including vinylidene fluoride, hexafluoropropylene, tetrafluoropropene, and the like. In another embodiment, the binder is a polyolefin such as polyethylene, polypropylene, or polybutene having any of a variety of molecular weight and density ranges. In another embodiment, the binder is selected from the group consisting of ethylene-diene-propene terpolymer, polystyrene, polymethyl methacrylate, polyethylene glycol, polyvinyl acetate, polyvinyl butyral, polyacetal, and polyethylene glycol diacrylate. In another embodiment, the binder is selected from the group consisting of methyl cellulose, carboxymethyl cellulose, styrene rubber, butadiene rubber, styrene-butadiene rubber, isoprene rubber, polyacrylamide, polyvinyl ether, polyacrylic acid, polymethacrylic acid, polyacrylonitrile, polyvinylidene fluoride polyacrylonitrile, and polyethylene oxide, hi another embodiment, the binder is selected from the group consisting of acrylate, styrene, epoxy, and silicone. Other suitable binders may be selected from polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, acrylonitrile-styrene-butadiene copolymer, polyimide or mixtures thereof.In yet another embodiment, the binder may be selected from polyvinylidene fluoride-hexafluoropropylene, polyvinylidene fluoride-trichloroethylene, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, ethylene-vinyl acetate copolymer, polyethylene oxide, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, acrylonitrile-styrene-butadiene copolymer, polyimide, polyethylene terephthalate, polybutylene terephthalate, polyester, polyacetal, polyamide, polyether ether ketone, polyethersulfone, polyphenylene oxide, polyphenylene sulfide, polyethylene naphthalene, and / or any combination thereof. In another embodiment, the binder is a copolymer or blend of two or more of the foregoing polymers.

[0119] The particulate material contained in the microporous separator material may also be selected from a wide range of materials. Generally, such materials have relatively low electrical and ionic conductivity at operating temperatures and do not corrode under the operating voltages of the battery electrodes or current collectors that contact the microporous separator material. For example, in one embodiment, the particulate material is in the range of 1×10 -4 By way of further example, in one embodiment, the particulate material has a conductivity of carrier ions (e.g., lithium) of less than 1×10 S / cm. -5 By way of further example, in one embodiment, the particulate material has a conductivity for carrier ions of less than 1×10 S / cm. -6Conductivity for carrier ions of less than 1000 S / cm. Exemplary particulate materials include particulate polyethylene, polypropylene, TiO2-polymer composite, silica aerogel, fumed silica, silica gel, silica hydrogel, silica xerogel, silica sol, colloidal silica, alumina, titania, magnesia, kaolin, talc, diatomaceous earth, calcium silicate, aluminum silicate, calcium carbonate, magnesium carbonate, or combinations thereof. For example, in one embodiment, the particulate material includes a particulate oxide or nitride, such as TiO2, SiO2, Al2O3, GeO2, BO3, Bi2O3, BaO, ZnO, ZrO2, BN, Si3N4, or Ge3N4. See, e.g., P. Arora and J. Zhang, "Battery Separators," Chemical Reviews 2004, 104, 4419-4462. Other suitable particles include BaTiO3, Pb(Zr,Ti)O3 (PZT), Pb 1-x La x Zr 1-y Ti y O3(PLZT), PB(Mg3Nb 2 / 3 )O3-PbTiO3 (PMN-PT), hafnia (HfO2), SrTiO3, SnO2, CeO2, MgO, NiO, CaO, ZnO, ZrO2, YO3, Al2O3, TiO2, SiC, or mixtures thereof. In one embodiment, the particulate material has an average particle size of about 20 nm to 2 micrometers, more typically 200 nm to 1.5 micrometers. In one embodiment, the particulate material has an average particle size of about 500 nm to 1 micrometer.

[0120] In alternative embodiments, the particulate materials comprised in the microporous separator material may be bound together by techniques such as sintering, bonding, curing, etc., while maintaining the desired porosity for electrolyte penetration to provide ionic conductivity for battery function.

[0121] Microporous separator materials may be deposited by, for example, electrophoretic deposition of particulate separator material, where particles are held together by surface energies such as electrostatic attraction or van der Waals forces, slurry deposition of particulate separator material (including spin or spray coating), screen printing, dip coating, and electrostatic spray deposition. A binder may be included in the deposition process; for example, the particulate material may be deposited in a slurry with a dissolved binder that precipitates upon solvent evaporation, electrophoretically deposited in the presence of a dissolved binder material, or co-electrophoretically deposited with a binder and insulating particles, etc. Alternatively, or in addition, a binder may be added after the particles are deposited in or on the electrode structure; for example, the particulate material may be dispersed in an organic binder solution and dip- or spray-coated, followed by drying, melting, or cross-linking the binder material to provide adhesive strength.

[0122] In the assembled secondary battery 102, the microporous separator material may be infiltrated with a non-aqueous electrolyte suitable for use as the secondary battery electrolyte. Typically, the non-aqueous electrolyte comprises a lithium salt and / or mixture of salts dissolved in an organic solvent and / or solvent mixture. Exemplary lithium salts include inorganic lithium salts such as LiClO, LiBF, LiPF, LiAsF, LiCl, and LiBr, as well as inorganic lithium salts such as LiB(CH), LiN(SOCF), LiN(SOCF), LiNSOCF, LiNSOCF, LiNSOCF, LiNSOCF, LiNSOCF, LiNSOCF, LiNSOCF, LiNSOCF 11 , LiNSO2C6F 13 , and LiNSO2C7F 15As yet another example, the electrolyte can include sodium ions dissolved therein, such as, for example, any one or more of NaClO, NaPF, NaBF, NaCFSO, NaN(CFSO), NaN(CFS0), and NaC(CFSO). Similarly, salts of magnesium and / or potassium can be provided. For example, magnesium salts such as magnesium chloride (MgCl), magnesium bromide (MgBr), or magnesium iodide (MgI), and / or magnesium perchlorate (Mg(ClO)), magnesium nitrate (Mg(NO), magnesium sulfate (MgSO), magnesium tetrafluoroborate (Mg(BF), magnesium tetraphenylborate (Mg(B(CH)), magnesium hexafluorophosphate (Mg(PF), magnesium hexafluoroarsenate (Mg(AsF), magnesium perfluoroalkylsulfonate (Mg(R), magnesium hexafluorophosphate (Mg(PF)), magnesium hexafluoroarsenate (Mg(AsF) ...phosphate (Mg(PF)), magnesium hexafluoroarsenate (Mg(AsF)), magnesium perfluoroalkylsulfonate (Mg(R), magnesium hexafluorophosphate (Mg(PF)), magnesium hexafluorophosphate (Mg(PF)), magnesium hexafluoroarsenate (Mg(AsF)), magnesium perfluoroalkylsulfonate (Mg(R), magnesium hexafluorophosphate (Mg(PF)), magnesium hexafluorophosphate (Mg(PF)), magnesium hexafluorophosphate (Mg(PF)), magnesium hexafluorophosphate (Mg(PF)), magnesium hexafluorophosphate (Mg(PF)), magnesium hexafluorophosphate (Mg(PF)), magnesium hexafluorophosphate (Mg(PF)), f1 SO3)2), where R f1 is a perfluoroalkyl group), magnesium perfluoroalkylsulfonylimide (Mg((R f2 SO2)2N)2, where R f2A magnesium salt may be provided which may be at least one selected from the group consisting of magnesium hexaalkyldisilazide ((Mg(HRDS)2), where R is an alkyl group), and magnesium hexaalkyldisilazide ((Mg(HRDS)2), where R is an alkyl group). Exemplary organic solvents for dissolving the lithium salt include cyclic esters, linear esters, cyclic ethers, and linear ethers. Specific examples of cyclic esters include propylene carbonate, ethylene carbonate, butylene carbonate, γ-butyrolactone, vinylene carbonate, 2-methyl-γ-butyrolactone, acetyl-γ-butyrolactone, and γ-valerolactone. Specific examples of linear esters include dimethyl carbonate, diethyl carbonate, dibutyl carbonate, dipropyl carbonate, methyl ethyl carbonate, methyl butyl carbonate, methyl propyl carbonate, ethyl butyl carbonate, ethyl propyl carbonate, butyl propyl carbonate, alkyl propionates, dialkyl malonates, and alkyl acetates. Specific examples of cyclic ethers include tetrahydrofuran, alkyltetrahydrofurans, dialkyltetrahydrofurans, alkoxytetrahydrofurans, dialkoxytetrahydrofurans, 1,3-dioxolane, alkyl-1,3-dioxolanes, and 1,4-dioxolanes. Specific examples of chain ethers include 1,2-dimethoxyethane, 1,2-diethoxytane, diethyl ether, ethylene glycol dialkyl ethers, diethylene glycol dialkyl ethers, triethylene glycol dialkyl ethers, and tetraethylene glycol dialkyl ethers.

[0123] In yet another embodiment, the secondary battery 102 can include an electrolyte, which can be any of an organic electrolyte, an inorganic electrolyte, a solid polymer electrolyte, a gel polymer electrolyte, an inorganic solid electrolyte, a molten inorganic electrolyte, etc. In yet another embodiment in which the electrolyte is a solid electrolyte, the solid electrolyte itself can provide insulation between electrodes and passage of carrier ions therethrough, thereby eliminating the need for a separate separator layer. That is, in certain embodiments, the solid electrolyte can replace the separator 130 described in embodiments herein. In one embodiment, the solid polymer electrolyte can include any of polymers formed from polyethylene oxide (PEO), polyvinyl acetate (PVA), polyethyleneimine (PEI), polyvinylidene fluoride (PVDF), polyacrylonitrile (PAN), LiPON, and polymethyl methacrylate (PMMA) polymers or copolymers thereof. In another embodiment, a sulfide-based solid electrolyte may be provided, for example, the sulfide-based solid electrolyte may include at least one of lithium and / or phosphorus, such as at least one of LiS and P2S5, and / or other sulfides, such as SiS2, GeS2, Li3PS4, Li4P2S7, Li4SiS4, Li2S-P2S5, and 50Li4SiO4.50Li3BO3, and / or B2S3. Still other embodiments of the solid electrolyte may include nitrides, halides, and sulfates of lithium (Li), for example, Li3N, LiI, Li5NI2, Li3N-LiI-LiOH, LiSiO4, LiSiO4-LiI-LiOH, Li2SiS3, Li4SiO4, Li4SiO4-LiI-LiOH, and Li3PO4-Li2S-SiS2.

[0124] The present disclosure further includes the following enumerated embodiments:

[0125] Embodiment 1. A secondary battery that cycles between a charging state and a discharging state, the secondary battery includes a battery casing, an electrode assembly, carrier ions, and a non-aqueous electrolyte solution in the battery casing; the electrode assembly includes a group of unit cells, and each unit cell includes, in a stacked series, a unit cell portion of an electrode current collector layer, an electrode layer including an electrode active material, a separator layer, a counter electrode layer, and a unit cell portion of a counter electrode current collector layer; The unit cell has a width W measured in the stacking direction of the stacked body from the unit cell portion of the electrode current collector to the unit cell portion of the counter electrode current collector. uc and The electrode layer has a width W measured in the stacking direction of the stacked continuous body from the unit cell portion of the electrode current collector adjacent to the electrode layer to the separator layer adjacent to the electrode layer. E , a height H measured from the top surface to the bottom surface of the electrode layer in a second direction perpendicular to the stacking direction. E and a length L measured from the first surface to the second surface in a third direction perpendicular to the stacking direction and the height direction. E and a volume V bounded by the unit cell portion of the electrode current collector, the separator layer, the top surface of the electrode layer, the bottom surface of the electrode layer, the first end surface of the electrode layer, and the second end surface of the electrode layer. E and The electrode layer includes a population of spacer structures including a material other than the electrode active material, and the spacer population is spaced from the volume V E occupying a total volume within the electrode layer within a range of about 0.1% to about 35% of the total volume within the electrode layer.

[0126] Embodiment 2. A member of the spacer group is located within each sub-volume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; E and (ii) is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0127] Embodiment 3. A member of the spacer group is located within each sub-volume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; E and (ii) is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0128] Embodiment 4. A member of the spacer group is located within each sub-volume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; E and (ii) is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0129] Embodiment 5. A member of the spacer group is located within each sub-volume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; E and (ii) is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0130] Embodiment 6. When the secondary battery is charged from the discharged state to the charged state, the electrode layer comprises an electrode active material layer having a capacity to accept more than 1 mole of carrier ions per mole of electrode active material; 10. The secondary battery of any preceding enumerated embodiment, wherein the state of charge is at least 75% of the rated capacity of the secondary battery and the state of discharge is less than 25% of the rated capacity of the secondary battery.

[0131] Embodiment 7. The population of spacer structures includes a spacer material, the spacer material having a capacity to accommodate carrier ions of less than 1 mole of carrier ions per mole of spacer material when the secondary battery is charged from the discharged state to the charged state; 10. The secondary battery of any preceding enumerated embodiment, wherein the state of charge is at least 75% of the rated capacity of the secondary battery and the state of discharge is less than 25% of the rated capacity of the secondary battery.

[0132] Embodiment 8. The secondary battery of any preceding enumerated embodiment, wherein the population of spacer structures includes a spacer material having any one or more of a polymer material, an electrode active material, an electrode current collector material, a counter electrode current collector material, and a separator material.

[0133] Embodiment 9. The population of spacer structures comprises a spacer material; The spacer material may be selected from the group consisting of fluoropolymers derived from monomers including vinylidene fluoride, hexafluoropropylene, and tetrafluoropropene, polyolefins (such as polyethylene, polypropylene, or polybutene), ethylene-diene-propene terpolymers, polystyrene, polymethyl methacrylate, polyethylene glycol, polyvinyl acetate, polyvinyl butyral, polyacetal, and polyethylene glycol diacrylate, methylcellulose, carboxymethylcellulose, styrene rubber, butadiene rubber, styrene-butadiene rubber, isoprene rubber, polyacrylamide, polyvinyl ether, polyacrylic acid, polymethacrylic acid, polyacrylonitrile, polyvinylidene fluoride polyacrylonitrile, polyethylene oxide, acrylates, styrenes, epoxies, silicones, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, Cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, acrylonitrile-styrene-butadiene copolymer, polyimide, polyvinylidene fluoride-hexafluoropropylene, polyvinylidene fluoride-trichloroethylene, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, ethylene-vinyl acetate copolymer, polyethylene oxide, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, acrylonitrile-styrene-butadiene copolymer, polyimide, polyethylene terephthalate, polybutylene terephthalate, polyester, polyacetal, polyamide, polyether ether ketone, polyethersulfone, polyphenylene oxide, polyphenylene sulfide, polyethylene naphthalene,and / or any one or more of a copolymer combination thereof.

[0134] Embodiment 10. The secondary battery of any preceding enumerated embodiment, wherein the spacer population occupies at least 0.1%, at least 0.25%, at least 0.5%, and / or at least 0.75% of the total volume, and less than 35%, less than 25%, less than 10%, and / or less than 5% of the total volume V of the electrode layers.

[0135] Embodiment 11. A member of the spacer group is located within each sub-volume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; E and (ii) is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0136] Embodiment 12. The secondary battery includes a series of stacked sheets having the electrode layer and the counter electrode layer, the stacking direction is in a first direction, and the height H of the electrode layer is E is measured in a second direction perpendicular to the stacking direction, and the length L of the electrode layer E is measured in a third direction orthogonal to both the second direction and the stacking direction.

[0137] Embodiment 13. A secondary battery according to any of the preceding enumerated embodiments, wherein members of the group of spacer structures in each unit cell of the stacked series are aligned with other members of the group of spacer structures in the stacking direction.

[0138] Embodiment 14. The secondary battery of any preceding enumerated embodiment, wherein the secondary battery includes at least one unit cell, the at least one unit cell being wound continuously around an inner region with an inner winding of the unit cell having a smaller diameter than an outer winding of the unit cell, the diameter of the unit cell increasing with increasing radius from the inner region.

[0139] Embodiment 15. The stacked series is in a first direction, and the height H of the electrode layer E is measured in a second direction perpendicular to the stacking direction, and the length L of the electrode layer E is measured from a central region of the secondary battery to an outer section of the secondary battery along a longest dimension of the electrode layer corresponding to a winding path of the electrode layer.

[0140] Embodiment 16. A secondary battery as described in the preceding enumerated embodiment 14, wherein members of the group of spacer structures are aligned such that spacer structures disposed within the inner windings of the unit cells are aligned in the stacking direction with spacer structures within the outer windings of the unit cells.

[0141] Embodiment 17. A secondary battery as described in enumerated preceding embodiment 16, wherein the distance between spacers disposed within the electrode layer along the longest dimension of the electrode layer increases as the radius from the inner region of the secondary battery to the outer region of the secondary battery increases.

[0142] Embodiment 18. The group of spacer structures has a length L of the electrode layer. E 10. The secondary battery of any preceding enumerated embodiment, comprising a plurality of spacer structures disposed within the electrode layer along

[0143] Embodiment 19. A secondary battery according to any preceding enumerated embodiment, wherein the population of spacer structures includes a single spacer structure located at the periphery of the electrode layer.

[0144] Embodiment 20. The group of spacer structures has a width W of the electrode layer. E 10. The secondary battery of any preceding enumerated embodiment, comprising one or more members of the group extending from the electrode current collector to the separator layer through

[0145] Embodiment 21. The group of spacer structures has a width W of the electrode layer. E The median value of the range extending from the first surface of the electrode current collector layer to the first surface of the separator layer opposite to the first surface of the electrode current collector layer along the E and the width W of the electrode layer is less than 60%, less than 50%, less than 40%, and / or less than 25% of the width W of the electrode layer. E 4. The secondary battery of any preceding enumerated embodiment, wherein the .lambda.

[0146] Embodiment 22. A first adjacent unit cell and a second adjacent unit cell, wherein the first adjacent unit cell and the second adjacent unit cell respectively include a first electrode layer and a second electrode layer, and share an electrode current collector; 10. The secondary battery of any preceding enumerated embodiment, wherein both the first adjacent unit cell and the second adjacent unit cell include populations of spacer structures within their respective first and second electrode layers.

[0147] Embodiment 23. The secondary battery of enumerated embodiment 22, wherein the first adjacent unit cell and the second adjacent unit cell share the same population of spacer structures that extend through the shared electrode current collector and into each of the first and second electrode layers.

[0148] Embodiment 24. A semiconductor device comprising a first unit cell and a second unit cell, the first unit cell and the second unit cell comprising a first electrode layer and a second electrode layer, respectively, and comprising a first population of spacer structures and a second population of spacer structures within the first electrode layer and the second electrode layer, respectively; 10. The secondary battery of any preceding enumerated embodiment, wherein positions of a first group of the spacer structures in the first electrode layer are aligned in a stacking direction with positions of a second group of the spacer structures in the second electrode layer.

[0149] Embodiment 25. A secondary battery according to any preceding enumerated embodiment, wherein the population of spacer structures is disposed at an interface between the electrode layer and the separator layer.

[0150] Embodiment 26. A secondary battery according to any preceding enumerated embodiment, wherein the population of spacer structures is disposed at an interface between the electrode layer and the surface of the current collector layer.

[0151] Embodiment 27. The electrode layer has less than 70% voids, less than 60% voids, less than 25% voids, and / or 10% or less voids within the total volume V of the electrode layer. E 10. The secondary battery of any preceding enumerated embodiment, having as a percentage

[0152] Embodiment 28. The secondary battery of any preceding enumerated embodiment, wherein the ratio of the electrical conductivity of the electrode active material in the electrode layer to the total electrical conductivity of all members of the spacer population in the electrode layer is at least 2:1, at least 5:1, and / or at least 50:1.

[0153] Embodiment 29. An electrode assembly for a secondary battery that cycles between a charged state and a discharged state, the electrode assembly includes a group of unit cells, and each unit cell includes, in a stacked series, a unit cell portion of an electrode current collector layer, an electrode layer including an electrode active material, a separator layer, a counter electrode layer, and a unit cell portion of a counter electrode current collector layer; The unit cell has a width W measured in the stacking direction of the stacked body from the unit cell portion of the electrode current collector to the unit cell portion of the counter electrode current collector. uc and The electrode layer has a width W measured in the stacking direction from the unit cell portion of the electrode current collector adjacent to the electrode layer to the separator layer adjacent to the electrode layer. e a height He measured from the top surface to the bottom surface of the electrode layer in a second direction perpendicular to the stacking direction, a length Le measured from the first surface to the second surface in a third direction perpendicular to the stacking direction and the height direction, and a volume V bounded by the unit cell portion of the electrode current collector, the separator layer, the top surface of the electrode layer, the bottom surface of the electrode layer, the first end surface of the electrode layer, and the second end surface of the electrode layer. E and The electrode layer includes a population of spacer structures, the population of spacers extending over the volume V of the electrode layer. E the electrode assembly occupies a total volume within the electrode layer in the range of about 0.1% to about 35% of the total volume within the electrode layer.

[0154] Embodiment 30. A member of the spacer group is located within each sub-volume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; E and (ii) is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0155] Embodiment 31. A member of the spacer group is located within each sub-volume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; E and (ii) the electrode assembly of any of enumerated embodiments 29-30 is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0156] Embodiment 32. A member of the spacer group is located within each sub-volume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; E and (ii) the electrode assembly of any preceding enumerated embodiment 29-31 is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0157] Embodiment 33. A member of the spacer group is located within each sub-volume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; E and (ii) is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0158] Embodiment 34. When the secondary battery is charged from the discharged state to the charged state, the electrode layer comprises an electrode active material layer having a capacity to accept more than 1 mole of carrier ions per mole of electrode active material; 34. The electrode assembly of any of enumerated previous embodiments 29 to 33, wherein the charged state is at least 75% of the rated capacity of the secondary battery, and the discharged state is less than 25% of the rated capacity of the secondary battery.

[0159] Embodiment 35. The population of spacer structures includes a spacer material, the spacer material having a capacity to accommodate carrier ions of less than 1 mole of carrier ions per mole of spacer material when the secondary battery is charged from the discharged state to the charged state; 35. The electrode assembly of any of enumerated preceding embodiments 29 to 34, wherein the charged state is at least 75% of the rated capacity of the secondary battery, and the discharged state is less than 25% of the rated capacity of the secondary battery.

[0160] Embodiment 36. An electrode assembly described in any of the preceding enumerated embodiments 29 to 35, wherein the collection of spacer structures includes a spacer material, the spacer material having any one or more of a polymer material, an electrode active material, an electrode current collector material, a counter electrode current collector material, and a separator material.

[0161] Embodiment 37. The population of spacer structures comprises a spacer material; The spacer material may be selected from the group consisting of fluoropolymers derived from monomers including vinylidene fluoride, hexafluoropropylene, and tetrafluoropropene, polyolefins (such as polyethylene, polypropylene, or polybutene), ethylene-diene-propene terpolymers, polystyrene, polymethyl methacrylate, polyethylene glycol, polyvinyl acetate, polyvinyl butyral, polyacetal, and polyethylene glycol diacrylate, methylcellulose, carboxymethylcellulose, styrene rubber, butadiene rubber, styrene-butadiene rubber, isoprene rubber, polyacrylamide, polyvinyl ether, polyacrylic acid, polymethacrylic acid, polyacrylonitrile, polyvinylidene fluoride polyacrylonitrile, polyethylene oxide, acrylates, styrenes, epoxies, silicones, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, Cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, acrylonitrile-styrene-butadiene copolymer, polyimide, polyvinylidene fluoride-hexafluoropropylene, polyvinylidene fluoride-trichloroethylene, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, ethylene-vinyl acetate copolymer, polyethylene oxide, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, acrylonitrile-styrene-butadiene copolymer, polyimide, polyethylene terephthalate, polybutylene terephthalate, polyester, polyacetal, polyamide, polyether ether ketone, polyethersulfone, polyphenylene oxide, polyphenylene sulfide, polyethylene naphthalene,37. The electrode assemblies of the preceding enumerated embodiment 36, comprising any one or more of: and / or copolymer combinations thereof.

[0162] Embodiment 38. The spacer population is at least 0.1%, at least 0.25%, at least 0.5%, and / or at least 0.75% of the total volume, and the total volume V of the electrode layer. E 38. The electrode assembly of any of the preceding enumerated embodiments 29 to 37, wherein the electrode assembly comprises less than 35%, less than 25%, less than 10%, and / or less than 5% of the total surface area.

[0163] Embodiment 39. A member of the spacer group is located within each sub-volume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; E and (ii) the electrode assembly of any preceding enumerated embodiment 29-38, wherein the unit cell portion is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0164] Embodiment 40. The electrode assembly includes a series of stacked sheets having the electrode layer and the counter electrode layer, the stacking direction is in a first direction, and the height H of the electrode layer E is measured in a second direction perpendicular to the stacking direction, and the length L of the electrode layer E is measured in a third direction perpendicular to both the second direction and the stacking direction.

[0165] Embodiment 41. An electrode assembly as described in the preceding enumerated embodiment 40, wherein members of the group of spacer structures in each unit cell of the stacked series are aligned with other members of the group of spacer structures in the stacking direction.

[0166] Embodiment 42. An electrode assembly described in any of the preceding enumerated embodiments 29 to 41, wherein the electrode assembly includes at least one unit cell, the at least one unit cell being wound continuously around an inner region with an inner winding of the unit cell having a smaller diameter than an outer winding of the unit cell, and the diameter of the unit cell increasing with increasing radius from the inner region.

[0167] Embodiment 43. The stacked series is in a first direction, and the height H of the electrode layer E is measured in a second direction perpendicular to the stacking direction, and the length L of the electrode layer E 43. The electrode assembly of claim 42, wherein the length is measured from the central region of the electrode assembly to the outer section of the electrode assembly along the longest dimension of the electrode layer corresponding to a winding path of the electrode layer.

[0168] Embodiment 44. An electrode assembly as described in the preceding enumerated embodiment 43, wherein members of the group of spacer structures are aligned such that spacer structures disposed within the inner windings of the unit cells are aligned in the stacking direction with spacer structures within the outer windings of the unit cells.

[0169] Embodiment 45. An electrode assembly as described in the preceding enumerated embodiment 44, wherein the distance between spacers disposed within the electrode layer along the longest dimension of the electrode layer increases as the radius from the inner region of the secondary battery to the outer region of the electrode assembly increases.

[0170] Embodiment 46. The group of spacer structures has a length L of the electrode layer. E 46. ​​The electrode assembly of any of enumerated embodiments 29 to 45, comprising a plurality of spacer structures disposed within the electrode layer along a line.

[0171] Embodiment 47. An electrode assembly described in any of the preceding enumerated embodiments 29 to 46, wherein the population of spacer structures includes a single spacer structure located at the periphery of the electrode layer.

[0172] Embodiment 48. The group of spacer structures has a width W of the electrode layer. E 48. The electrode assembly of any preceding enumerated embodiment 29-47, comprising one or more members of the group extending from the electrode current collector to the separator layer through a

[0173] Embodiment 49. The group of spacer structures has a width W of the electrode layer. E The median value of the range extending from the first surface of the electrode current collector layer to the first surface of the separator layer opposite to the first surface of the electrode current collector layer along the E and the width W of the electrode layer is less than 60%, less than 50%, less than 40%, and / or less than 25% of the width W of the electrode layer. E 49. The electrode assembly of any of the preceding enumerated embodiments 29 to 48, wherein the SiO 2 content is at least 2%, at least 3%, and / or at least 5% of the SiO 2 content.

[0174] Embodiment 50. A semiconductor device including a first adjacent unit cell and a second adjacent unit cell, wherein the first adjacent unit cell and the second adjacent unit cell include a first electrode layer and a second electrode layer, respectively, and share an electrode current collector; 50. The electrode assembly of any preceding enumerated embodiment 29-49, wherein both the first adjacent unit cell and the second adjacent unit cell include populations of spacer structures within their respective first and second electrode layers.

[0175] Embodiment 51. The electrode assembly of enumerated embodiment 50, wherein the first adjacent unit cell and the second adjacent unit cell share the same population of spacer structures that extend through the shared electrode current collector into each of the first electrode layer and the second electrode layer.

[0176] Embodiment 52. A semiconductor device comprising a first unit cell and a second unit cell, the first unit cell and the second unit cell comprising a first electrode layer and a second electrode layer, respectively, and comprising a first population of spacer structures and a second population of spacer structures within the first electrode layer and the second electrode layer, respectively; 52. The electrode assembly of any of enumerated preceding embodiments 29 to 51, wherein the positions of a first group of spacer structures in the first electrode layer are aligned in a stacking direction with the positions of a second group of spacer structures in the second electrode layer.

[0177] Embodiment 53. An electrode assembly according to any preceding enumerated embodiment 29-52, wherein the population of spacer structures is disposed at an interface between the electrode layer and the separator layer.

[0178] Embodiment 54. An electrode assembly according to any preceding enumerated embodiment 29-53, wherein the population of spacer structures is disposed at the interface between the electrode layer and the surface of the current collector layer.

[0179] Embodiment 55. The electrode layer has at least 40% voids, at least 50% voids, at least 60% voids, at least 75% voids, and / or at least 90% voids within the total volume V of the electrode layer. E 55. The electrode assembly of any of the preceding enumerated embodiments 29 to 54, having as a percentage

[0180] Embodiment 56. An electrode assembly described in any of the preceding enumerated embodiments 29 to 55, wherein the ratio of the electrical conductivity of the electrode active material in the electrode layer to the total electrical conductivity of all members of the spacer group in the electrode layer is at least 2:1, at least 5:1, and / or at least 50:1.

[0181] Embodiment 57. A method of forming a secondary battery that cycles between a charged state and a discharged state, comprising: Providing an electrode assembly, carrier ions, and a non-aqueous electrolyte solution in a battery housing, the electrode assembly includes a group of unit cells, and each unit cell includes, in a stacked series, a unit cell portion of an electrode current collector layer, an electrode layer including an electrode active material, a separator layer, a counter electrode layer, and a unit cell portion of a counter electrode current collector layer; The unit cell has a width W measured in the stacking direction of the stacked body from the unit cell portion of the electrode current collector to the unit cell portion of the counter electrode current collector. uc The electrode layer has a width W measured in the stacking direction from the unit cell portion of the electrode current collector adjacent to the electrode layer to the separator layer adjacent to the electrode layer. e , a height H measured from the top surface to the bottom surface of the electrode layer in a direction perpendicular to the stacking direction E and a length Le measured from a first surface to a second surface in a direction perpendicular to the stacking direction and the height direction, and a volume Ve defined by the unit cell portion of the electrode current collector, the separator layer, the top surface of the electrode layer, the bottom surface of the electrode layer, a first end surface of the electrode layer, and a second end surface of the electrode layer, the electrode layer includes a population of spacer structures, the population of spacers occupying a total volume within the electrode layer within a range of about 0.1% to about 35% of the volume Ve of the electrode layer; said providing; performing a formation process including charging the secondary battery from a discharged state to a charged state; The method comprising:

[0182] Embodiment 58. A member of the spacer group is located within each sub-volume of the electrode layer; 58. The method of enumerated embodiment 57, wherein the electrode layer (i) comprises at least 50% of the volume V of the electrode layer, and (ii) is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0183] Embodiment 59. A member of the spacer group is located within each sub-volume of the electrode layer; 59. The method of any preceding enumerated embodiment 57, wherein the electrode layer (i) comprises at least 40% of the volume V of the electrode layer; and (ii) is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0184] Embodiment 60. A member of the spacer group is located within each sub-volume of the electrode layer; 60. The method of any preceding enumerated embodiment 57-59, wherein the electrode layer (i) comprises at least 30% of the volume V of the electrode layer, and (ii) is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0185] Embodiment 61. A member of the spacer group is located within each sub-volume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; E and (ii) is bounded by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

[0186] Embodiment 62. The electrode layer has a first volume of solid electrode active material before the forming process and a second volume of solid electrode active material after the forming process that is greater than the first volume; The method further comprises: providing a W of the unit cell from before the forming process to after the forming process that is less than 1%, less than 0.5%, less than 0.25%, and / or less than 0.1%.UC 62. The method of any preceding enumerated embodiment 57-61, comprising performing the forming process to increase the volume of the solid electrode active material in the electrode layer to the second volume that is at least 3%, at least 5%, at least 10%, at least 25%, at least 50%, at least 75%, and / or at least 100% greater than the first volume of the solid electrode active material in the electrode layer, relative to a change in

[0187] Embodiment 63. A method according to any of the preceding enumerated embodiments 57 to 62, further comprising providing an electrode constraint set that constrains the growth of the electrode assembly in the stacking direction and / or maintains the alignment of the group of unit cells within the electrode assembly during the formation process.

[0188] Embodiment 64. The method of enumerated embodiment 63, wherein the electrode constraint set constrains growth in the stacking direction.

[0189] Embodiment 65. The method of any preceding enumerated embodiment 63-64, comprising removing the electrode restraint set following the forming process.

[0190] Embodiment 66. The method of any preceding enumerated embodiment 63-65, comprising providing the electrode constraint set within the housing of the secondary battery.

[0191] Embodiment 67. The method of any of the preceding enumerated embodiments 63 to 66, comprising providing the electrode constraint set on the outside of the housing of the secondary battery.

[0192] Embodiment 68. The method of any of the preceding enumerated embodiments 63-67, wherein the electrode assembly includes any of the preceding enumerated embodiments 29-56, and the secondary battery includes any of the preceding enumerated embodiments 1-28.

[0193] Incorporation by Reference All publications and patents mentioned herein are incorporated by reference in their entirety for all purposes to the same extent as if each individual publication or patent was specifically and individually indicated to be incorporated by reference. In case of conflict, the present application, including any definitions herein, will control.

[0194] equivalent While specific embodiments have been discussed, the above specification is illustrative and not restrictive. Many variations will become apparent to those skilled in the art upon consideration of this specification. The full scope of the present embodiments should be determined by reference to the claims, along with their full scope of equivalents, and the specification, along with such variations.

[0195] Unless otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term "about." Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and appended claims are approximations that may vary depending upon the desired properties sought to be obtained.

Claims

1. A secondary battery that alternates between a charging state and a discharging state, the secondary battery includes a battery casing, an electrode assembly, carrier ions, and a nonaqueous electrolyte solution in the battery casing; the electrode assembly includes a group of unit cells, and each unit cell includes, in a stacked series, a unit cell portion of an electrode current collector layer, an electrode layer including an electrode active material, a separator layer, a counter electrode layer, and a unit cell portion of a counter electrode current collector layer; The unit cell has a width W measured in the stacking direction of the stacked body from the unit cell portion of the electrode current collector to the unit cell portion of the counter electrode current collector. ｕｃ and The electrode layer has a width W measured in the stacking direction of the stacked body from the unit cell portion of the electrode current collector adjacent to the electrode layer to the separator layer adjacent to the electrode layer. Ｅ , a height H measured from the top surface to the bottom surface of the electrode layer in a second direction perpendicular to the stacking direction Ｅ and L measured from the first surface to the second surface in a third direction perpendicular to the stacking direction and the height direction. Ｅ and a volume V bounded by the unit cell portion of the electrode current collector, the separator layer, the top surface of the electrode layer, the bottom surface of the electrode layer, the first end surface of the electrode layer, and the second end surface of the electrode layer. Ｅ and the electrode layer includes a population of spacer structures, the population of spacer structures includes a material other than the electrode active material, and (a) the population of spacer structures is spaced from the volume V of the electrode layer; Ｅ (b) a member of the spacer group is located within each subvolume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; Ｅ and (ii) is bounded on all sides by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

2. when the secondary battery is charged from the discharged state to the charged state, the electrode layer comprises an electrode active material layer having a capacity to accept more than 1 mole of carrier ions per mole of electrode active material; 2. The secondary battery of claim 1, wherein the state of charge is at least 75% of the rated capacity of the secondary battery, and the state of discharge is less than 25% of the rated capacity of the secondary battery.

3. the population of spacer structures includes a spacer material, the spacer material having a capacity to accommodate carrier ions of less than 1 mole of carrier ions per mole of spacer material when the secondary battery is charged from the discharged state to the charged state; 3. The secondary battery according to claim 1, wherein the charged state is at least 75% of the rated capacity of the secondary battery, and the discharged state is less than 25% of the rated capacity of the secondary battery.

4. 4. The secondary battery according to claim 1, wherein the group of spacer structures includes a spacer material including any one or more of a polymer material, an electrode active material, an electrode current collector material, a counter electrode current collector material, and a separator material.

5. the population of spacer structures includes a spacer material; The spacer material may be a fluoropolymer derived from a monomer including vinylidene fluoride, hexafluoropropylene, tetrafluoropropene, a polyolefin (such as polyethylene, polypropylene, or polybutene), an ethylene-diene-propene terpolymer, polystyrene, polymethyl methacrylate, polyethylene glycol, polyvinyl acetate, polyvinyl butyral, polyacetal, and polyethylene glycol diacrylate, methyl cellulose, carboxymethyl cellulose, styrene rubber, butadiene rubber, styrene-butadiene rubber, or the like. rubber, isoprene rubber, polyacrylamide, polyvinyl ether, polyacrylic acid, polymethacrylic acid, polyacrylonitrile, polyvinylidene fluoride polyacrylonitrile, polyethylene oxide, acrylates, styrenes, epoxies, silicones, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, acrylonitrile-styrene-butadiene copolymer, polyimide, polyvinylidene fluoride-hexafluoropropylene, polyvinylidene fluoride-trichloroethylene, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, ethylene-vinyl acetate copolymer, polyethylene oxide, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, acrylonitrile-styrene-butadiene copolymer, polyimide, polyethylene terephthalate, polybutylene terephthalate, polyester, polyacetal, polyamide, polyether ether ketone, polyethersulfone, polyphenylene oxide, polyphenylene sulfide, polyethylene naphthalene,and / or a combination of copolymers thereof.

6. 6. The secondary battery according to claim 1, wherein the spacer population occupies at least 0.1%, at least 0.25%, at least 0.5%, and / or at least 0.75% of the total volume and less than 35%, less than 25%, less than 10%, and / or less than 5% of the total volume Ve of the electrode layers.

7. a member of the spacer group is located within each subvolume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; Ｅ and (ii) is bounded on all sides by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

8. the secondary battery includes a series of laminated sheets having the electrode layer and the counter electrode layer; The stacking direction is in a first direction, and the height H Ｅ is measured in a second direction perpendicular to the stacking direction, and the length L of the electrode layer Ｅ is measured in a third direction perpendicular to both the second direction and the stacking direction.

9. The secondary battery according to claim 8 , wherein members of the group of spacer structures in each unit cell of the stacked series are aligned with other members of the group of spacer structures in the stacking direction.

10. 10. The secondary battery according to claim 1, wherein the secondary battery includes at least one unit cell, the at least one unit cell being continuously wound around an inner region with an inner winding of the unit cell having a smaller diameter than an outer winding of the unit cell, and the diameter of the unit cell increasing as the radius from the inner region increases.

11. The stacked series is in a first direction, and the height H Ｅ is measured in a second direction perpendicular to the stacking direction, and the length L of the electrode layer Ｅ is measured along the longest dimension of the electrode layer corresponding to a winding path of the electrode layer from a central region of the secondary battery to an outer section of the secondary battery.

12. 11. The secondary battery of claim 10, wherein members of the group of spacer structures are aligned such that spacer structures disposed within the inner windings of the unit cells are aligned in the stacking direction with spacer structures within the outer windings of the unit cells.

13. 13. The secondary battery of claim 12, wherein a distance between spacers disposed within the electrode layer along the longest dimension of the electrode layer increases as a radius from the inner region of the secondary battery to the outer region of the secondary battery increases.

14. The group of spacer structures has a length L of the electrode layer. Ｅ 14. The secondary battery according to claim 1, further comprising a plurality of spacer structures arranged in the electrode layer along a line.

15. 15. The secondary battery according to claim 1, wherein the group of spacer structures includes a single spacer structure located on the periphery of the electrode layer.

16. The group of spacer structures has a width W of the electrode layer. Ｅ 16. The secondary battery according to claim 1, comprising one or more members of the group extending from the electrode current collector to the separator layer through a

17. The group of spacer structures has the width W of the electrode layer. Ｅ The median value of the range extending from the first surface of the electrode current collector layer to the first surface of the separator layer opposite to the first surface of the electrode current collector layer along the Ｅ and the width W of the electrode layer is less than 60%, less than 50%, less than 40%, and / or less than 25% of the width W of the electrode layer. Ｅ The secondary battery according to any one of claims 1 to 16, wherein the ionic current density is at least 2%, at least 3%, and / or at least 5% of the ionic current density.

18. a first adjacent unit cell and a second adjacent unit cell, the first adjacent unit cell and the second adjacent unit cell including a first electrode layer and a second electrode layer, respectively, and sharing an electrode current collector; 18. The secondary battery of claim 1, wherein both the first adjacent unit cell and the second adjacent unit cell include a population of spacer structures within their respective first electrode layers and second electrode layers.

19. 20. The secondary battery of claim 18, wherein the first adjacent unit cell and the second adjacent unit cell share the same population of spacer structures that extend through the shared electrode current collector and into each of the first and second electrode layers.

20. a first unit cell and a second unit cell, the first unit cell and the second unit cell including a first electrode layer and a second electrode layer, respectively, and including a first population of spacer structures and a second population of spacer structures within the first electrode layer and the second electrode layer, respectively; 20. The secondary battery according to claim 1, wherein positions of a first group of the spacer structures in the first electrode layer are aligned in a stacking direction with positions of a second group of the spacer structures in the second electrode layer.

21. 21. The secondary battery according to claim 1, wherein the group of spacer structures is disposed at the interface between the electrode layer and the separator layer.

22. 22. The secondary battery according to claim 1, wherein the group of spacer structures is disposed at the interface between the electrode layer and the surface of the current collector layer.

23. The electrode layer may have less than 70% voids, less than 60% voids, less than 25% voids, and / or 10% or less voids within the total volume V of the electrode layer. Ｅ The secondary battery according to any one of claims 1 to 22, wherein the percentage of

24. 24. The secondary battery according to claim 1, wherein the ratio of the electrical conductivity of the electrode active material in the electrode layer to the total electrical conductivity of all members of the spacer group in the electrode layer is at least 2:1, at least 5:1, and / or at least 50:

1.

25. An electrode assembly for a secondary battery that alternates between a charged state and a discharged state, the electrode assembly includes a group of unit cells, and each unit cell includes, in a stacked series, a unit cell portion of an electrode current collector layer, an electrode layer including an electrode active material, a separator layer, a counter electrode layer, and a unit cell portion of a counter electrode current collector layer; The unit cell has a width W measured in the stacking direction of the stacked body from the unit cell portion of the electrode current collector to the unit cell portion of the counter electrode current collector. ｕｃ and The electrode layer has a width W measured in the stacking direction from the unit cell portion of the electrode current collector adjacent to the electrode layer to the separator layer adjacent to the electrode layer. ｅ a height He measured from the top surface to the bottom surface of the electrode layer in a second direction perpendicular to the stacking direction, a length Le measured from the first surface to the second surface in a third direction perpendicular to the stacking direction and the height direction, and a volume V bounded by the unit cell portion of the electrode current collector, the separator layer, the top surface of the electrode layer, the bottom surface of the electrode layer, a first end surface of the electrode layer, and a second end surface of the electrode layer. Ｅ and the electrode layer includes a population of spacer structures, and (a) the spacer population is spaced from the volume V of the electrode layer; Ｅ (b) a member of the spacer group is located within each subvolume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; Ｅ and (ii) is bounded on all sides by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

26. when the secondary battery is charged from the discharged state to the charged state, the electrode layer comprises an electrode active material layer having a capacity to accept more than 1 mole of carrier ions per mole of electrode active material; 26. The electrode assembly according to claim 25, wherein the state of charge is at least 75% of the rated capacity of the secondary battery, and the state of discharge is less than 25% of the rated capacity of the secondary battery.

27. the population of spacer structures includes a spacer material, the spacer material having a capacity to accommodate carrier ions of less than 1 mole of carrier ions per mole of spacer material when the secondary battery is charged from the discharged state to the charged state; The electrode assembly according to any one of claims 25 to 26, wherein the charged state is at least 75% of the rated capacity of the secondary battery, and the discharged state is less than 25% of the rated capacity of the secondary battery.

28. 28. The electrode assembly according to claim 25, wherein the group of spacer structures includes a spacer material, and the spacer material includes any one or more of a polymer material, an electrode active material, an electrode current collector material, a counter electrode current collector material, and a separator material.

29. the population of spacer structures includes a spacer material; The spacer material may be a fluoropolymer derived from a monomer including vinylidene fluoride, hexafluoropropylene, tetrafluoropropene, a polyolefin (such as polyethylene, polypropylene, or polybutene), an ethylene-diene-propene terpolymer, polystyrene, polymethyl methacrylate, polyethylene glycol, polyvinyl acetate, polyvinyl butyral, polyacetal, and polyethylene glycol diacrylate, methyl cellulose, carboxymethyl cellulose, styrene rubber, butadiene rubber, styrene-butadiene rubber, or the like. rubber, isoprene rubber, polyacrylamide, polyvinyl ether, polyacrylic acid, polymethacrylic acid, polyacrylonitrile, polyvinylidene fluoride polyacrylonitrile, polyethylene oxide, acrylates, styrenes, epoxies, silicones, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, acrylonitrile-styrene-butadiene copolymer, polyimide, polyvinylidene fluoride-hexafluoropropylene, polyvinylidene fluoride-trichloroethylene, polymethyl methacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, ethylene-vinyl acetate copolymer, polyethylene oxide, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, acrylonitrile-styrene-butadiene copolymer, polyimide, polyethylene terephthalate, polybutylene terephthalate, polyester, polyacetal, polyamide, polyether ether ketone, polyethersulfone, polyphenylene oxide, polyphenylene sulfide, polyethylene naphthalene,and / or a copolymer combination thereof.

30. 30. The electrode assembly of claim 25, wherein the spacer population occupies at least 0.1%, at least 0.25%, at least 0.5%, and / or at least 0.75% of the total volume and less than 35%, less than 25%, less than 10%, and / or less than 5% of the total volume V of the electrode layers.

31. a member of the spacer group is located within each subvolume of the electrode layer; The electrode layer is configured to: (i) define the volume V of the electrode layer; Ｅ and (ii) is bounded on all sides by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer.

32. the electrode assembly includes a series of laminated sheets having the electrode layer and the counter electrode layer; The stacking direction is in a first direction, and the height H Ｅ is measured in a second direction perpendicular to the stacking direction, and the length L of the electrode layer Ｅ is measured in a third direction perpendicular to both the second direction and the stacking direction.

33. 33. The electrode assembly according to claim 32, wherein members of the group of spacer structures in each unit cell of the stacked series are aligned with other members of the group of spacer structures in the stacking direction.

34. 34. The electrode assembly according to any one of claims 25 to 33, wherein the electrode assembly includes at least one unit cell, the at least one unit cell being wound continuously around an inner region with an inner winding of the unit cell having a smaller diameter than an outer winding of the unit cell, the diameter of the unit cell increasing with an increasing radius from the inner region.

35. The stacked series is in a first direction, and the height H Ｅ is measured in a second direction perpendicular to the stacking direction, and the length L of the electrode layer Ｅ 35. The electrode assembly of claim 34, wherein is measured from a central region of the electrode assembly to an outer section of the electrode assembly along the longest dimension of the electrode layer corresponding to a winding path of the electrode layer.

36. 36. The electrode assembly of claim 35, wherein members of the group of spacer structures are aligned such that spacer structures disposed within the inner windings of the unit cells are aligned in the stacking direction with spacer structures within the outer windings of the unit cells.

37. 37. The electrode assembly of claim 36, wherein the distance between spacers disposed within the electrode layer along the longest dimension of the electrode layer increases as the radius from the inner region of the secondary battery to the outer region of the electrode assembly increases.

38. The group of spacer structures has a length L of the electrode layer. Ｅ 38. The electrode assembly according to claim 25, further comprising a plurality of spacer structures arranged in the electrode layer along a line.

39. 39. The electrode assembly according to claim 25, wherein the group of spacer structures includes a single spacer structure located at the periphery of the electrode layer.

40. The group of spacer structures has a width W of the electrode layer. Ｅ 40. The electrode assembly of claim 25, comprising one or more members of the group extending from the electrode current collector to the separator layer through a

41. The group of spacer structures has the width W of the electrode layer. Ｅ The median value of the range extending from the first surface of the electrode current collector layer to the first surface of the separator layer opposite to the first surface of the electrode current collector layer along the Ｅ and the width W of the electrode layer is less than 60%, less than 50%, less than 40%, and / or less than 25% of the width W of the electrode layer. Ｅ The electrode assembly according to any one of claims 25 to 40, wherein the surface area is at least 2%, at least 3%, and / or at least 5% of the surface area.

42. a first adjacent unit cell and a second adjacent unit cell, the first adjacent unit cell and the second adjacent unit cell including a first electrode layer and a second electrode layer, respectively, and sharing one electrode current collector; 42. The electrode assembly of claim 25, wherein both the first adjacent unit cell and the second adjacent unit cell include a population of spacer structures within their respective first and second electrode layers.

43. 43. The electrode assembly of claim 42, wherein the first adjacent unit cell and the second adjacent unit cell share the same population of spacer structures that extend through the shared electrode current collector into each of the first and second electrode layers.

44. a first unit cell and a second unit cell, the first unit cell and the second unit cell including a first electrode layer and a second electrode layer, respectively, and including a first population of spacer structures and a second population of spacer structures within the first electrode layer and the second electrode layer, respectively; 44. The electrode assembly of claim 25, wherein the positions of the first group of spacer structures in the first electrode layer are aligned in the stacking direction with the positions of the second group of spacer structures in the second electrode layer.

45. 45. The electrode assembly according to claim 25, wherein the group of spacer structures is disposed at an interface between the electrode layer and the separator layer.

46. 46. ​​The electrode assembly according to claim 25, wherein the group of spacer structures is disposed at the interface between the electrode layer and the surface of the current collector layer.

47. The electrode layers may have at least 40% voids, at least 50% voids, at least 60% voids, at least 75% voids, and / or at least 90% voids within the total volume V of the electrode layers. Ｅ The electrode assembly according to any one of claims 25 to 46, wherein the percentage of

48. 48. The electrode assembly according to any one of claims 25 to 47, wherein the ratio of the electrical conductivity of the electrode active material in the electrode layer to the total electrical conductivity of all members of the spacer group in the electrode layer is at least 2:1, at least 5:1, and / or at least 50:

1.

49. 1. A method for forming a secondary battery that cycles between a charged state and a discharged state, comprising: Providing an electrode assembly, carrier ions, and a non-aqueous electrolyte solution in a battery housing, the electrode assembly includes a group of unit cells, and each unit cell includes, in a stacked series, a unit cell portion of an electrode current collector layer, an electrode layer including an electrode active material, a separator layer, a counter electrode layer, and a unit cell portion of a counter electrode current collector layer; The unit cell has a width W measured in the stacking direction of the stacked body from the unit cell portion of the electrode current collector to the unit cell portion of the counter electrode current collector. ｕｃ and The electrode layer has a width W measured in the stacking direction from the unit cell portion of the electrode current collector adjacent to the electrode layer to the separator layer adjacent to the electrode layer. ｅ , a height H measured from the top surface to the bottom surface of the electrode layer in a direction perpendicular to the stacking direction Ｅ and a length Le measured from a first surface to a second surface in a direction perpendicular to the stacking direction and the height direction, and a volume Ve defined by the unit cell portion of the electrode current collector, the separator layer, the top surface of the electrode layer, the bottom surface of the electrode layer, a first end surface of the electrode layer, and a second end surface of the electrode layer, the electrode layer includes a population of spacer structures, (a) the spacer population occupies a total volume within the electrode layer within a range of about 0.1% to about 35% of the volume Ve of the electrode layer, and (b) a member of the spacer population is located within each sub-volume of the electrode layer; the electrode layer (i) comprises at least 25% of the volume Ve of the electrode layer, and (ii) is bounded on all sides by (aa) the unit cell portion of the electrode current collector, (bb) the separator layer, (cc) the top surface of the electrode layer, (dd) the bottom surface of the electrode layer, (ee) the first end surface of the electrode layer, and (ff) the second end surface of the electrode layer; said providing; performing a formation process including charging the secondary battery from a discharged state to a charged state; The method comprising:

50. the electrode layer having a first volume of solid electrode active material before the forming process and a second volume of solid electrode active material after the forming process that is greater than the first volume; The method further comprises: providing a W value of the unit cell from before the forming process to after the forming process that is less than 1%, less than 0.5%, less than 0.25%, and / or less than 0.1%. ＵＣ 50. The method of claim 49, comprising performing the forming process to increase the volume of the solid electrode active material in the electrode layer to the second volume that is at least 3%, at least 5%, at least 10%, at least 25%, at least 50%, at least 75%, and / or at least 100% greater than the first volume of the solid electrode active material in the electrode layer relative to a change in

51. 51. The method of any of claims 49-50, further comprising providing a set of electrode constraints that constrain growth of the electrode assembly in the stacking direction and / or maintain alignment of a population of unit cells within the electrode assembly during the formation process.

52. 52. The method of claim 51, wherein the electrode constraint set constrains growth in the stacking direction.

53. A method according to any of claims 51 to 52, including removing the electrode constraint set following the forming process.

54. The method of any one of claims 51 to 53, comprising providing the electrode constraint set within the housing of the secondary battery.

55. The method of any one of claims 51 to 54, comprising providing the electrode constraint set on the outside of the housing of the secondary battery.

56. The electrode assembly includes any one of claims 25 to 50, The method according to any one of claims 51 to 55, wherein the secondary battery comprises any one of claims 1 to 24.

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