Dispersed cell formation system for lithium-containing batteries

Abstract

A cell formation system for lithium-containing secondary batteries includes a population of formation clusters, each formation cluster including a connector configured to connect to a lithium-containing secondary battery, a charging module connected to the connector and configured to charge the battery, a pre-lithiation module connected to the connector and configured to diffuse lithium into an electrode active material layer of the battery, a discharge module connected to the connector and configured to discharge the battery, and a communication interface for communicatively coupling the formation cluster to a central controller. The formation cluster is configured to, in response to instructions received from the central controller, charge the battery using the charging module, diffuse lithium into the electrode active material layer of the battery using the pre-lithiation module, and discharge the secondary battery using the discharge module after lithium has diffused into the electrode active material layer of the battery.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 63 / 202,930, filed June 30, 2021, the disclosure of which is incorporated by reference in its entirety.

[0002] The field of the disclosure relates generally to the formation of secondary batteries, and more specifically to a distributed cell formation system for lithium-containing secondary batteries. [Background technology]

[0003] In a rocking chair battery cell, both the positive and negative electrodes of the secondary battery contain a material into which carrier ions, such as lithium, can be inserted and extracted. When the battery is discharged, carrier ions are extracted from the negative electrode and inserted into the positive electrode. When the battery is charged, carrier ions are extracted from the positive electrode and inserted into the negative electrode.

[0004] Silicon has become a promising candidate to replace carbonaceous materials as anodes due to its high specific capacity. For example, a graphite anode formed from LiC6 can have a specific capacity of about 370 milliampere-hours per gram (mAh / g), while a Li 15 Crystalline silicon anodes formed from Si4 can have a specific capacity of about 3600 mAh / g, nearly 10 times higher than graphite anodes. However, the use of silicon anodes has been limited due to the large volume change (e.g., 300%) of silicon when Li carrier ions are inserted into the silicon anode. This volume increase, together with the cracking and pulverization associated with charge and discharge cycles, has limited the practical use of silicon anodes. In addition, the use of silicon anodes has been limited due to their poor initial coulombic efficiency (ICE), which leads to capacity loss during the initial formation of secondary batteries utilizing silicon anodes.

[0005] After the lithium-containing secondary batteries are assembled, the assembled batteries are typically subjected to a formation process. During the formation process, the batteries are slowly charged and discharged one or more times. At least some known formation processes include a pre-lithiation process to add lithium to the batteries. These formation processes are typically performed by large-scale centralized systems. Such systems include a central control center connected to all the batteries undergoing the formation process. The central control center directly controls the charging, discharging, and (where applicable) pre-lithiation of all the batteries to which it is connected. To control the formation process and enable the distribution of power to a large number of batteries, the central control center is a relatively large and expensive system that uses a significant amount of power, occupies a significant amount of space, and utilizes a large number of wires to connect to all of the batteries undergoing formation. Summary of the Invention

[0006] In one aspect, a cell formation system for a lithium-containing secondary battery includes a population of forming clusters. Each forming cluster of the population of forming clusters includes a connector configured to connect to a lithium-containing secondary battery. Each lithium-containing secondary battery includes a population of bilayers, an electrode bus bar, and a counter electrode bus bar. Each bilayer of the population of bilayers includes an electrode structure, a separator structure, and a counter electrode structure. The electrode structure of each member of the bilayer population includes an electrode current collector and an electrode active material layer, and the counter electrode structure of each member of the bilayer population includes a counter electrode current collector and a counter electrode active material layer. Each forming cluster of the population of forming clusters also includes a charging module connected to the connector and configured to charge the lithium-containing secondary battery connected to the connector, a pre-lithiation module connected to the connector and configured to diffuse lithium into the electrode active material layer of the lithium-containing secondary battery connected to the connector, a discharging module connected to the connector and configured to discharge the lithium-containing secondary battery connected to the connector, and a communication interface for communicatively coupling the forming cluster to a central controller. The formation cluster is configured, in response to instructions received from the central controller, to charge a lithium-containing secondary battery connected to the connector using the charging module, to diffuse lithium into an electrode active material layer of the lithium-containing secondary battery using the pre-lithiation module after the lithium-containing secondary battery has been charged, and to discharge the lithium-containing secondary battery using the discharging module after lithium has been diffused into an electrode active material layer of the lithium-containing secondary battery using the pre-lithiation module.

[0007] In another aspect, a forming cluster for connecting to a single lithium-containing secondary battery in a cell forming system for lithium-containing secondary batteries includes a connector configured to connect to the lithium-containing secondary battery. Each lithium-containing secondary battery includes a bilayer population, an electrode bus bar, and a counter electrode bus bar. Each bilayer of the bilayer population includes an electrode structure, a separator structure, and a counter electrode structure. The electrode structure of each member of the bilayer population includes an electrode current collector and an electrode active material layer, and the counter electrode structure of each member of the bilayer population includes a counter electrode current collector and a counter electrode active material layer. The forming cluster also includes a charging module connected to the connector and charging the lithium-containing secondary battery connected to the connector, a pre-lithiation module connected to the connector and diffusing lithium into the electrode active material layer of the lithium-containing secondary battery connected to the connector, a discharging module connected to the connector and discharging the lithium-containing secondary battery connected to the connector, and at least one microcontroller. The at least one microcontroller is programmed to charge a lithium-containing secondary battery connected to the connector using the charging module, to diffuse lithium into an electrode active material layer of the lithium-containing secondary battery using the pre-lithiation module after the lithium-containing secondary battery is charged, and to discharge the lithium-containing secondary battery using the discharging module after lithium has been diffused into an electrode active material layer of the lithium-containing secondary battery using the pre-lithiation module.

[0008] In yet another aspect, a distributed cell formation system for lithium-containing secondary batteries includes a central controller and a population of formation clusters located remotely from the central controller. The central controller includes a processor, a memory, and a communication interface. Each formation cluster is configured to perform a plurality of steps of a cell formation process for a single lithium-containing secondary battery. Each lithium-containing secondary battery includes a population of bilayers, an electrode bus bar, and a counter electrode bus bar. Each bilayer of the population of bilayers includes an electrode structure, a separator structure, and a counter electrode structure. The electrode structure of each member of the bilayer population includes an electrode current collector and an electrode active material layer, and the counter electrode structure of each member of the bilayer population includes a counter electrode current collector and a counter electrode active material layer. Each formation cluster includes a connector configured for connection to a lithium-containing secondary battery, a population of modules, each module of the population of modules configured to perform a different one of a plurality of steps on a lithium-containing secondary battery connected to the connector, a communication interface communicatively coupled to the central controller, and at least one microcontroller. At least one microcontroller is programmed to control the population of modules to perform a number of steps of a cell formation process in response to instructions received from the central controller.

[0009] Various refinements exist on the features mentioned in relation to the above aspects. Further features may also be incorporated into the above aspects. These refinements and additional features may exist individually or in any combination. For example, various features discussed below in relation to any of the illustrated embodiments may be incorporated alone or in any combination into any of the above aspects. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is a perspective view of an exemplary embodiment of a secondary battery. [Diagram 2] Draw a unit cell of the secondary battery of Figure 1. [Diagram 3]Draw the cathode structure of the unit cell in Figure 2. [Figure 4] Draw the anode structure for the unit cell in Figure 2. [Diagram 5] 1 illustrates a perspective view of an exemplary embodiment of a cushioning system; [Figure 6] Draw an exploded view of the cushioning system of Figure 5. [Figure 7] 1 depicts a perspective view of an exemplary embodiment auxiliary pole; [Figure 8] Draw an exploded view of the auxiliary pole in Figure 7. [Figure 9] 8 is a perspective view of the auxiliary pole of FIG. 7 at one stage in the assembly process of the auxiliary pole of FIG. 7. [Figure 10] 8 is a perspective view of the auxiliary pole of FIG. 7 at another stage in the assembly process of the auxiliary pole of FIG. 7. [Figure 11] 8 is a perspective view of the auxiliary pole of FIG. 7 at yet another stage in the assembly process of adding an extending tab to the auxiliary pole of FIG. 7. [Figure 12] 6 is a perspective view of the cushioning system of FIG. 5 at one stage in the assembly process of the cushioning system. [Figure 13] 6 is a perspective view of the cushioning system of FIG. 5 at another stage in the assembly process of the cushioning system. [Figure 14] 6 is a perspective view of the cushioning system of FIG. 5 at yet another stage in the assembly process of the cushioning system. [Figure 15] FIG. 15 is a cross-sectional view of a portion of the cushioning system of FIG. [Figure 16] 6 is a perspective view of the cushioning system of FIG. 5 at yet another stage in the assembly process of the cushioning system. [Figure 17] FIG. 6 is a perspective view of the buffering system of FIG. 5 after performing a buffering process on the secondary battery. [Figure 18] 1 is a flowchart of a method for pre-lithiating a secondary battery with carrier ions using an auxiliary electrode of an exemplary embodiment. [Figure 19] 19 is a flowchart depicting further details of the method of FIG. 18. [Figure 20]19 is a flowchart depicting further details of the method of FIG. 18. [Figure 21] 19 is a flowchart depicting further details of the method of FIG. 18. [Figure 22] FIG. 1 is a block diagram of an exemplary cell formation system for a lithium-containing secondary battery. [Figure 23] FIG. 23 is a block diagram of an exemplary forming cluster for use in the cell forming system of FIG. 22. [Figure 24] FIG. 24 is a block diagram of an exemplary pre-lithiation module for use in the formation cluster of FIG. 23. [Diagram 25] FIG. 25 is a simplified circuit diagram of an exemplary embodiment of a switched-capacitor circuit for use in the pre-lithiation module of FIG. [Figure 26] 26 is a graph of a series of PFM control pulses applied to the switches of the switched-capacitor circuit of FIG. 25 as a function of time. [Figure 27] 27 is a graph of the resulting current through the auxiliary electrode in response to the control pulses of FIG. 26 as a function of time. [Figure 28] FIG. 25 is a circuit diagram of an example implementation of a switched-capacitor circuit for use in the pre-lithiation module of FIG. [Figure 29] 1 is a graph of a buffer current for use as part of an exemplary pre-lithiation profile. [Diagram 30] 1 is a graph of the duration of pulses of an exemplary pre-lithiation profile. [Diagram 31] 1 is a graph of the number of pulses for an exemplary pre-lithiation profile. [Diagram 32] FIG. 32 is a graph of the cathode-anode voltage and the cathode-auxiliary electrode voltage as a function of time when prelithiating using the prelithiation profiles of FIGS. 29-31. [Diagram 33] FIG. 32 is a graph of buffer current as a function of time when prelithiating using the prelithiation profiles of FIGS. 29-31.

[0011] definition As used herein, "A," "an," and "the" (i.e., singular) refer to plural references unless the context clearly dictates otherwise. For example, in one example, reference to an "electrode" includes both a single electrode and a plurality of 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 micrometers (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 numbers expressing quantities (e.g., measurements, and the like) and the like used in the specification and claims are to be understood as being modified in all instances by the term "about". Thus, unless otherwise indicated to the contrary, the numerical parameters set forth in the following specification and the appended claims are approximations. Each numerical parameter should be construed, at least in light of the reported significant digits and by applying ordinary rounding techniques.

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

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

[0015] As used herein, "cathode" in reference to a secondary battery refers to the positive electrode in the secondary battery.

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

[0017] "Conversion chemically active material" or "conversion chemistry" refers to a material that undergoes a chemical reaction during the charge and discharge cycle of a secondary battery.

[0018] As used herein, "counter electrode" may refer to either the negative or positive electrode (anode or cathode) of a secondary battery, unless the context clearly indicates otherwise.

[0019] As used herein, "counter electrode current collector" may refer to the negative or positive (anode or cathode) current collector opposite the negative electrode current connector of a secondary battery, unless the context clearly indicates otherwise.

[0020] In the context of cycling a secondary battery between a charging state and a discharging state, "cycling" as used herein refers to charging and / or discharging the battery to move the battery 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., a charging state if the first state was discharged, or a discharging state if the first state was charged), 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 may include charging the battery from a discharging state to a charging state and then returning to the discharging state to complete the cycle, as in a charging cycle. A single cycle may also include discharging the battery from a charging state to a discharging state and then charging back to a charging state to complete the cycle, as in a discharging cycle.

[0021] As used herein, "electrochemically active material" means an anode active material or a cathode active material.

[0022] As used herein, "electrode" may refer to either the negative or positive electrode (anode or cathode) of a secondary battery, unless the context clearly indicates otherwise.

[0023] As used herein, "electrode current collector" may refer to either the negative or positive (anode or cathode) current collector of a secondary battery, unless the context clearly indicates otherwise.

[0024] As used herein, "electrode material" may refer to either an anode material or a cathode material, unless the context clearly indicates otherwise.

[0025] As used herein, "electrode structure" may refer to an anode structure (e.g., anode structure) or a cathode structure (e.g., cathode structure) adapted for use in a battery, unless the context clearly indicates otherwise.

[0026] "Capacity" or "C", as used herein, unless the context clearly indicates otherwise, refers to the amount of charge that a battery (or a subportion of a battery including one or more pairs of electrode and counter electrode structures forming a bilayer) can deliver at a given voltage.

[0027] "Electrolyte," as used herein, unless the context clearly indicates otherwise, refers to a non-metallic liquid, gel, or solid material adapted for use in a battery in which electrical current is carried by the movement of ions.

[0028] 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 specified capacity, unless the context clearly indicates otherwise. For example, a battery may be charged to at least 80% of its specified capacity, at least 90% of its specified capacity, or even at least 95% of its specified capacity, such as 100% of its specified capacity.

[0029] "Discharge capacity," as used herein with respect to the negative electrode, means the amount of carrier ions available for extraction from the negative electrode and insertion into the positive electrode during a discharge operation of the battery between a given set of cell end-of-charge and cell end-of-discharge voltage limits, unless the context clearly indicates otherwise.

[0030] A "discharged state," as used herein in the context of the state of a secondary battery, refers to a state in which a secondary battery is discharged to less than 25% of its specified capacity, unless the context clearly indicates otherwise. For example, a battery may be discharged to less than 20% of its specified capacity, such as less than 10% of its specified capacity, or even less than 5% of its specified capacity, such as 0% of its specified capacity.

[0031] "Reversible Coulombic capacity," as used herein with reference to an electrode (i.e., positive, negative, or auxiliary electrode), means the total capacity of the electrode for carrier ions available for reversible exchange with the counter electrode.

[0032] As used herein, "longitudinal axis", "lateral axis", and "vertical axis" refer to mutually perpendicular axes (i.e., each perpendicular to the other). For example, "longitudinal axis", "lateral axis", and "vertical axis" as used herein are akin to a Cartesian coordinate system used to define three-dimensional aspects or orientations. As such, the description of the elements of the subject matter disclosed herein is not limited to the particular axis(es) used to describe the three-dimensional orientation of the elements. Alternatively stated, the axes may be interchangeable when referring to three-dimensional aspects of the disclosed subject matter.

[0033] As used herein, "composite material" or "composite" refers to a material that includes two or more constituent materials, unless the context clearly indicates otherwise.

[0034] As used herein, "porosity" or "porosity" or "void volume fraction" refers to a measurement of void (i.e., empty) space in a material and is the fraction of the volume of voids relative to the total volume of the material as a percentage from 0 to 1, or 0% to 100%.

[0035] "Polymer," as used herein, unless the context clearly indicates otherwise, may refer to a substance or material composed of repeating macromolecular subunits.

[0036] As used herein, unless the context clearly indicates otherwise, "microstructure" may refer to the structure of the surface of a material as revealed by an optical microscope at a magnification of greater than about 25 times.

[0037] As used herein, unless the context clearly indicates otherwise, "microporous" may refer to a material that contains pores having diameters of less than about 2 nanometers.

[0038] As used herein, "macroporous" may refer to materials that contain pores having diameters greater than about 50 nanometers, unless the context clearly indicates otherwise.

[0039] As used herein, "nanoscale" or "nanoscopic scale" can refer to structures having length scales ranging from about 1 nanometer to about 100 nanometers.

[0040] As used herein, “pre-lithiation” or “pre-lithiating” may refer to the addition of lithium to the active lithium content of a lithium-containing secondary battery as part of the formation process prior to operation of the battery to compensate for the loss of active lithium. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0041] The embodiments of the present disclosure provide a distributed formation process in which modern electronic devices and distributed embedded network strategies are adopted. Thus, instead of a centralized system that requires a dedicated connection to every battery undergoing the formation process and controls the formation process of hundreds or thousands of batteries, the formation process in the exemplary embodiments of the present disclosure is distributed among smaller clusters, each of which directly handles the formation process of the battery to which it is connected. These embodiments can simplify the construction of the formation system by requiring a less powerful central controller and less interconnection wiring, while allowing the formation processing system to be more easily scaled and physically distributed to desired locations.

[0042] Some embodiments of the present disclosure may provide advantages such as mitigation or amelioration of poor ICE associated with silicon-based anodes in secondary batteries utilizing an auxiliary anode electrochemically coupled with the secondary battery to provide additional carrier ions during and / or after initial battery formation. The use of the auxiliary anode mitigates the initial loss of carrier ions in the secondary battery during initial formation, thereby providing the technical advantage of, for example, increasing the capacity of the secondary battery after formation. Furthermore, the introduction of additional carrier ions after battery formation mitigates the cycle-based loss of carrier ions typically lost through secondary reactions, thereby providing the technical advantage of reducing capacity loss per cycle in the secondary battery. Still further, the introduction of additional carrier ions after battery formation improves the cycle performance of the secondary battery by maintaining the anode of the secondary battery at a lower potential voltage during discharge since the anode contains additional carrier ions. In some embodiments, the auxiliary anode is removed from the secondary battery after formation, thereby providing the technical advantage of increasing the energy density of the battery.

[0043] Figure 1 is a perspective view of an exemplary embodiment of a secondary battery 100, and Figure 2 illustrates a unit cell 200 for the secondary battery 100. The secondary battery 100 of Figure 1 has an exposed portion that shows a portion of the internal structure of the secondary battery, as described further below.

[0044] As illustrated in FIG. 1, the secondary battery 100 includes a plurality of adjacent subunits 102. Each electrode subunit 102 has dimensions of an X-axis, a Y-axis, and a Z-axis, respectively. The X-axis, the Y-axis, and the Z-axis are each perpendicular to each other, similar to a Cartesian coordinate system. As used herein, the dimension of each electrode subunit 102 in the Z-axis may be referred to as the "height", the dimension in the X-axis may be referred to as the "length", and the dimension in the Y-axis may be referred to as the "width". The electrode subunits 102 may be combined into one or more unit cells 200 (see FIG. 2). Each of the unit cells 200 includes at least one anode active material layer 104 and at least one cathode active material layer 106. The anode active material layer 104 and the cathode active material layer 106 are electrically insulated from each other by a separator layer 108. It should be understood that in preferred embodiments of the present disclosure, any number of electrode subunits 102 may be used in the secondary battery 100, such as 1 to 200 or more electrode subunits 102.

[0045] Referring to FIG. 1, the secondary battery 100 includes a first bus bar 110 and a second bus bar 112, which are in electrical contact with the anode active material layer 104 and the cathode active material layer 106 of each of the subunits 102, respectively, via electrode tabs 114. The electrode tabs 114 are only visible on a first side 120 of the secondary battery 100 in FIG. 1, but a different set of electrode tabs 114 is present on a second side 121 of the secondary battery. The electrode tabs 114 on the first side 120 of the secondary battery 100 are electrically coupled to the first bus bar 110, which may be referred to as an anode bus bar. The electrode tabs 114 on the second side 121 of the secondary battery 100 (not visible in FIG. 1) are electrically coupled to the second bus bar 112, which may be referred to as a cathode bus bar. In this embodiment, the first bus bar 110 is electrically coupled to a first electrical terminal 124 of the secondary battery 100, which is electrically conductive. If the first bus bar 110 comprises a positive bus bar for the secondary battery 100, the first electrical terminal 124 comprises a negative terminal for the secondary battery 100. Further, in this embodiment, the second bus bar 112 is electrically coupled to a second electrical terminal 125 of the secondary battery 100, which is electrically conductive. If the second bus bar 112 comprises a negative bus bar for the secondary battery 100, the second electrical terminal 125 comprises a positive terminal for the secondary battery 100.

[0046] In one embodiment, a casing 116, which may be referred to as a constraint, may be applied over one or both of the XY surfaces of the secondary battery 100. In the embodiment shown in Figure 1, the casing 116 includes a number of perforations 118 to facilitate electrolyte distribution or flow once the secondary battery 100 is fully assembled. In one embodiment, the casing 116 includes stainless steel, such as SS301, SS316, 440C, or 440C hard. In other embodiments, the casing 116 is made of aluminum (e.g., aluminum 7075-T6, hard H18, etc.), titanium (e.g., 6Al-4V), beryllium, beryllium copper (hard), copper (O2 free, hard), nickel, other metals or metal alloys, composites, polymers, ceramics (e.g., alumina (e.g., sintered or Coorstek AD96), zirconia (e.g., Coorstek YZTP), yttria stabilized zirconia (e.g., ENrG E-Strate®)), glass, tempered glass, polyetheretherketone (PEEK) (e.g., Aptiv 1102), PEEK with carbon (e.g., Victrex 90HMF40 or Xycomp 1000-04), polyphenylene sulfide (PPS) with carbon (e.g., Tepex Dynalite 207), polyetherketone (PEEK) with 30% glass (e.g., Victrex 90HMF40 or Xycomp 1000-04), Polyimide (e.g., Kapton®), E Glass Std Fabric / Epoxy, 0°, E Glass UD / Epoxy, 0°, Kevlar Std Fabric / Epoxy, 0°, Kevlar UD / Epoxy, 0°, Carbon Std Fabric / Epoxy, 0°, Carbon UD / Epoxy, 0°, Toyobo Zylon® HM Fiber / Epoxy, Kevlar 49 Aramid Fiber, S Glass Fibers, Carbon Fibers, Vectran UM LCP Fibers, Dyneema, Zylon or other suitable materials.

[0047] In some embodiments, the casing 116 comprises a sheet having a thickness ranging from about 10 to about 100 micrometers (μm). In one embodiment, the casing 116 comprises a stainless steel sheet (e.g., SS316) having a thickness of about 30 μm. In another embodiment, the casing 116 comprises an aluminum sheet (e.g., 7075-T6) having a thickness of about 40 μm. In another embodiment, the casing 116 comprises a zirconia sheet (e.g., Coorstek YZTP) having a thickness of about 30 μm. In another embodiment, the casing 116 comprises an E-glass UD / epoxy 0 degree sheet having a thickness of about 75 μm. In another embodiment, the casing 116 comprises 12 μm carbon fiber with a packing density of >50%.

[0048] In this embodiment, secondary battery 100 includes a first major surface 126 and a second major surface 127 opposite first major surface 126. Major surfaces 126, 127 of secondary battery 100 may be substantially planar in some embodiments.

[0049] Referring to FIG. 2, which shows the secondary battery 100 along the cut line DD in FIG. 1, individual layers of a unit cell 200, which may be the same or similar to the electrode subunit 102, are depicted. For each of the unit cells 200, in some embodiments, the separator layer 108 is an ion-permeable microporous polymeric material suitable for use as a separator in a secondary battery. In one embodiment, the separator layer 108 is coated with ceramic particles on one or both sides. In this embodiment, the unit cell 200 includes a positive electrode current collector 202 in the center, which may include or be electrically coupled to one of the electrode tabs 114 on one of the sides 120, 121 of the secondary battery 100 (see FIG. 1). The unit cell 200 further includes a positive electrode active material layer 104, a separator layer 108, a negative electrode active material layer 106, and a negative electrode current collector 204 in a stacked configuration. The negative electrode current collector 204 may include or be electrically coupled to one of the electrode tabs 114 on one of the sides 120 , 121 of the secondary battery 100 that is different from the positive electrode current collector 202 .

[0050] In an alternative embodiment, the arrangement of the cathode active material layer 106 and the anode active material layer 104 may be swapped such that the cathode active material layer is toward the center and the anode active material layer is distal to the cathode active material layer. In one embodiment, unit cell 200A includes, stacked in succession from left to right, an anode current collector 202, an anode active material layer 104, a separator layer 108, a cathode active material layer 106, and a cathode current collector 204. In an alternative embodiment, unit cell 200B includes, stacked in succession from left to right, a separator layer 108, a first layer of cathode active material layer 106, a cathode current collector 204, a second layer of cathode active material layer 106, a separator layer 108, a first layer of anode active material layer 104, an anode current collector 202, a second layer of anode active material layer 104, and a separator layer 108.

[0051] 2 , the layered structure comprising the cathode active material layer 106 and the cathode current collector 204 may be referred to as a cathode structure 206, while the layered structure comprising the anode active material layer 104 and the anode current collector 202 may be referred to as an anode structure 207. Collectively, the collection of cathode structures 206 for the secondary battery 100 may be referred to as the positive electrode 208 of the secondary battery 100, and the collection of anode structures 207 for the secondary battery 100 (only one of the anode structures 207 is shown in FIG. 2 ) may be referred to as the negative electrode 209 of the secondary battery 100.

[0052] A voltage difference V exists between adjacent cathode structures 206 and anode structures 207, the adjacent structures being considered bilayers in some embodiments. Each bilayer has a capacity C determined by the configuration and construction of the cathode structures 206 and anode structures 207. In this embodiment, each bilayer produces a voltage difference of about 4.35 volts. In other embodiments, each bilayer has a voltage difference of about 0.5 volts, about 1.0 volts, about 1.5 volts, about 2.0 volts, about 2.5 volts, about 3.0 volts, about 3.5 volts, about 4.0 volts, 4.5 volts, about 5.0 volts, 4-5 volts, or any other suitable voltage. During cycling between charge and discharge states, the voltage may vary, for example, between about 2.5 volts and about 4.35 volts. The capacity C of the bilayer in this embodiment is about 3.5 milliamp hours (mAh). In other embodiments, the capacity C of the bilayer is about 2 mAh, less than 5 mAh, or any other suitable capacity. In some embodiments, the capacity C of the bilayer can be up to about 10 mAh.

[0053] The cathode current collector 204 may include aluminum, nickel, cobalt, titanium, and tungsten, or alloys thereof, or any other material suitable for use as a cathode current collector layer. 3 For example, in one such embodiment, the cathode current collector 204 has a conductivity of at least about 10 4 By way of further example, in one such embodiment, the cathode current collector 204 has a conductivity of at least about 10 5The cathode current collector 204 has a conductivity of Siemens / cm. In general, the cathode current collector 204 may include a metal such as aluminum, carbon, chromium, gold, nickel, NiP, palladium, platinum, rhodium, ruthenium, alloys of silicon and nickel, titanium, or combinations 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 cathode current collector 204 includes gold or an alloy thereof, such as gold silicide. By way of further example, in one embodiment, the cathode current collector 204 includes nickel or an alloy thereof, such as nickel silicide.

[0054] The cathode active material layer 106 can be an intercalation-type chemically active material, a conversion chemically active material, or a combination thereof.

[0055] Exemplary conversion chemical materials useful in the present disclosure include S (or the lithiated form LiS), LiF, Fe, Cu, Ni, FeF, FeO d F 3.2d , FeF3, CoF3, CoF2, CuF2, NiF2, and the like, where 0≦d≦0.5, and the like.

[0056] The exemplary cathode active material layer 106 also includes any of a wide range of intercalation-type cathode active materials. For example, in the case of a lithium-ion battery, the cathode active material may include a cathode active 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 may be used selectively. 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 are 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, molybdenum oxysulfide, phosphates, silicates, vanadates, sulfur, sulfur compounds, oxygen (air), Li(Ni x Mn y Co z ) O2, and combinations thereof.

[0057] Generally, the cathode active material layer 106 has a thickness of at least about 20 μm. For example, in one embodiment, the cathode active material layer 106 has a thickness of at least about 40 μm. By way of further example, in one such embodiment, the cathode active material layer 106 has a thickness of at least about 60 μm. By way of further example, in one such embodiment, the cathode active material layer 106 has a thickness of at least about 100 μm. Typically, the cathode active material layer 106 has a thickness of less than about 90 μm or less than about 70 μm.

[0058] FIG. 3 illustrates one of the cathode structures 206 of FIG. 2. Each cathode structure 206 has a longitudinal axis (A CE ) measured along the length (L CE ) and width (W CE ) and length L CEand width W CE The height (H CE ) and.

[0059] The total length L of the cathode structure 206 CE will vary depending on the secondary battery 100 and its intended use. In general, however, each cathode structure 206 typically has a length L in the range of about 5 millimeters (mm) to about 500 mm. CE For example, in one such embodiment, each cathode structure 206 has a length L of about 10 mm to about 250 mm. CE By way of further example, in one such embodiment, each cathode structure 206 has a length L of about 25 mm to about 100 mm. CE According to one embodiment, the cathode structure 206 includes one or more first electrode members having a first length and one or more second electrode members having a second length different from the first length. In yet another embodiment, the different lengths of the one or more first electrode members and the one or more second electrode members may be selected to conform to a predetermined shape of the electrode assembly, such as an electrode assembly shape having different lengths along one or more of the longitudinal and / or lateral axes, and / or to provide predetermined performance characteristics of the secondary battery 100.

[0060] Width W of cathode structure 206 CE will vary depending on the secondary battery 100 and its intended use. In general, however, the cathode structure 206 typically has a width W CE For example, in one embodiment, each cathode structure 206 has a width W CE By way of further example, in one embodiment, the width W of each cathode structure 206 ranges from about 0.025 mm to about 2 mm. CEis in the range of about 0.05 mm to about 1 mm. According to one embodiment, the cathode structure 206 includes one or more first electrode members having a first width and one or more second electrode members having a second width different from the first width. In yet another embodiment, the different widths of the one or more first electrode members and the one or more second electrode members may be selected to conform to a predetermined shape of the secondary battery 100, such as an assembly having different widths along one or more of the longitudinal and / or lateral axes, and / or to provide predetermined performance characteristics of the secondary battery 100.

[0061] Height H of cathode structure 206 CE will vary depending on the secondary battery 100 and its intended use. In general, however, the cathode structure 206 typically has a height H in the range of about 0.05 mm to about 25 mm. CE For example, in one embodiment, each cathode structure 206 has a height H CE By way of further example, in one embodiment, the height H of each cathode structure 206 ranges from about 0.05 mm to about 5 mm. CE is in the range of about 0.1 mm to about 1 mm. According to one embodiment, the cathode structure 206 includes one or more first cathode members having a first height and one or more second cathode members having a second height different from the first height. In yet another embodiment, the different heights of the one or more first cathode members and the one or more second cathode members may be selected to conform to a predetermined shape of the secondary battery 100, such as a shape having different heights along one or more of the longitudinal and / or lateral axes, and / or to provide predetermined performance characteristics of the secondary battery 100.

[0062] Generally, each cathode structure 206 has a width W CE substantially larger than its height H CE Length L substantially larger than CE For example, in one embodiment, for each cathode structure 206, L CE and W CE and H CE and each of the L CE and WCE and L are at least 5:1, respectively. CE and H CE and W are each at least 5:1. CE and H CE L for each CE is at least 10:1 for each cathode structure 206. By way of further example, in one embodiment, W CE and H CE L for each CE is at least 15:1 for each cathode structure 206. By way of further example, in one embodiment, W CE and H CE L for each CE is at least 20:1 for each cathode structure 206.

[0063] In one embodiment, the width W of the cathode structure 206 CE Height H CE and H are each at least 0.4:1. CE Against W CE is at least 2:1, respectively, for each cathode structure 206. By way of further example, in one embodiment, H CE Against W CE is at least 10:1, respectively, for each cathode structure 206. By way of further example, in one embodiment, H CE Against W CE The ratio of H is at least 20:1 for each cathode structure 206, respectively. CE Against W CE The ratio of H is generally less than 1,000:1, respectively, for each cathode structure 206. For example, in one embodiment, CE Against W CE is less than 500:1, respectively, for each cathode structure 206. By way of further example, in one embodiment, H CE Against W CE The ratio of H to H is less than 100:1, respectively. CE Against W CEand H are each less than 10:1. CE Against W CE The ratio ranges from about 2:1 to about 100:1 for each cathode structure 206, respectively.

[0064] Anode structure and materials 2, the anode current collector 202 in the unit cell 200 may comprise a conductive material such as copper, carbon, nickel, stainless steel, cobalt, titanium, and tungsten, and alloys thereof, or any other material suitable as an anode current collector layer. Generally, the anode current collector 202 has a thickness of at least about 10 3 For example, in one such embodiment, the anode current collector 202 has a conductivity of at least about 10 4 By way of further example, in one such embodiment, the anode current collector 202 has a conductivity of at least about 10 5 It has a conductivity in Siemens / cm.

[0065] Generally, the anode active material layer 104 in the unit cell 200 can be selected from the group consisting of: (a) silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), titanium (Ti), nickel (Ni), cobalt (Co), and cadmium (Cd); (b) alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Ni, Co, or Cd with other elements; (c) alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn , oxides, carbides, nitrides, sulfides, phosphides, selenides, and tellurides of Al, Ti, Fe, Ni, Co, V, or Cd, and mixtures, composites, or lithium-containing composites thereof; (d) salts and hydroxides of Sn; (e) lithium titanate, lithium manganate, lithium aluminate, lithium-containing titanium oxides, lithium transition metal oxides, ZnCo2O4; (f) particles of graphite and carbon; (g) lithium metal; and (h) combinations thereof.

[0066] Exemplary anode active material layer 104 includes graphite and soft or hard carbon, or carbon materials such as graphene (e.g., single-walled or multi-walled carbon nanotubes), or any of a range of metals, metalloids, alloys, oxides, nitrides, and compounds that can intercalate or alloy with lithium. Specific examples of metals or metalloids that can comprise the anode material include graphite, tin, lead, magnesium, aluminum, boron, gallium, silicon, Si / C composites, Si / graphite blends, silicon oxide (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 an exemplary embodiment, the anode active material includes aluminum, tin, or silicon, or oxides thereof, nitrides thereof, fluorides thereof, or other alloys thereof. In another exemplary embodiment, the anode active material layer 104 includes silicon or an alloy or oxide thereof.

[0067] In one embodiment, the anode active material layer 104 is microstructured to provide a significant void volume fraction to accommodate volumetric expansion and contraction as lithium ions (or other carrier ions) are incorporated into or exit the anode active material layer 104 during charging and discharging processes of the secondary battery 100. In general, the void volume fraction of the (each of) the anode active material layer 104 is at least 0.1. Typically, however, the void volume fraction of the (each of) the anode active material layer 104 is 0.8 or less. For example, in one embodiment, the void volume fraction of the (each of) the anode active material layer 104 is between about 0.15 and about 0.75. By way of further example, in one embodiment, the void volume fraction of the (each of) the anode active material layer 104 is between about 0.2 and about 0.7. By way of further example, in one embodiment, the void volume fraction of (each of) the anode active material layers 104 is between about 0.25 and about 0.6.

[0068] Depending on the composition of the microstructured anode active material layer 104 and the method of their formation, the microstructured anode active material layer 104 may comprise a macroporous, microporous, or mesoporous material layer, or a combination thereof, such as a combination of microporous and mesoporous, or a combination of mesoporous and macroporous. Microporous materials are typically characterized by pore dimensions of less than 10 nanometers (nm), wall dimensions of less than 10 nm, pore depths of 1 μm to 50 μm, and a pore morphology generally characterized by a "spongy" irregular appearance, non-smooth walls, and branched pores. Mesoporous materials are typically characterized by pore dimensions of 10 nm to 50 nm, wall dimensions of 10 nm to 50 nm, pore depths of 1 μm to 100 μm, and a pore morphology generally characterized by more or less well-defined branched or dendritic pores. Macroporous materials are typically characterized by pore dimensions greater than 50 nm, wall dimensions greater than 50 nm, pore depths between 1 μm and 500 μm, and pore morphologies that can be linear, branched, or dendritic, and smooth or rough-walled. In addition, the void volume can include open or closed porosity, or a combination thereof. In one embodiment, the void volume includes open porosity, i.e., the anode active material layer 104 includes porosity at the sides of the anode active material layer that has openings through which lithium ions (or other carrier ions) can enter or exit. For example, lithium ions can enter the anode active material layer 104 through the pore openings after leaving the cathode active material layer 106. In another embodiment, the void volume includes closed porosity, i.e., the anode active material layer 104 includes porosity that is enclosed. In general, open porosity can provide a larger interfacial surface area for carrier ions, while closed porosity tends to be less susceptible to SEI formation, each providing room for expansion of anode active material layer 104 upon the ingress of carrier ions. Thus, in certain embodiments, it is preferred that anode active material layer 104 include a combination of open and closed porosity.

[0069] In one embodiment, the anode active material layer 104 comprises porous aluminum, tin, or silicon, or alloys, oxides, or nitrides thereof. The porous silicon layer may be formed, for example, by anodization, by etching (e.g., by depositing a precious 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. In addition, the porous anode active material layer 104 generally has a porosity of at least about 0.1 but less than 0.8, and a thickness of about 1 μm to about 100 μm. For example, in one embodiment, the anode active material layer 104 comprises porous silicon, has a thickness of about 5 μm to about 100 μm, and has a porosity of about 0.15 to about 0.75. By way of further example, in one embodiment, the anode active material layer 104 comprises porous silicon, has a thickness of about 10 μm to about 80 μm, and has a porosity of about 0.15 to about 0.7. By way of further example, in one such embodiment, the anode active material layer 104 comprises porous silicon, has a thickness of about 20 μm to about 50 μm, and has a porosity of about 0.25 to about 0.6. By way of further example, in one such embodiment, the anode active material layer 104 comprises a porous silicon alloy (such as nickel silicide), has a thickness of about 5 μm to about 100 μm, and has a porosity of about 0.15 to about 0.75.

[0070] In another embodiment, the anode active material layer 104 comprises fibers of aluminum, tin, or silicon, or alloys thereof. The individual fibers may have a diameter (thickness dimension) of about 5 nm to about 10,000 nm and a length that generally corresponds to the thickness of the anode active material layer 104. The silicon fibers (nanowires) may be formed by, for example, chemical vapor deposition or other techniques known in the art, such as vapor-liquid-solid (VLS) growth and solid-liquid-solid (SLS) growth. In addition, the anode active material layer 104 generally has a porosity of at least about 0.1 but less than 0.8, and a thickness of about 1 μm to about 200 μm. For example, in one embodiment, the anode active material layer 104 comprises silicon nanowires, has a thickness of about 5 μm to about 100 μm, and a porosity of about 0.15 to about 0.75. By way of further example, in one embodiment, anode active material layer 104 comprises silicon nanowires, has a thickness of about 10 μm to about 80 μm, and a porosity of about 0.15 to about 0.7. By way of further example, in one such embodiment, anode active material layer 104 comprises silicon nanowires, has a thickness of about 20 μm to about 50 μm, and a porosity of about 0.25 to about 0.6. By way of further example, in one such embodiment, anode active material layer 104 comprises silicon alloy (such as nickel silicide) nanowires, has a thickness of about 5 μm to about 100 μm, and a porosity of about 0.15 to about 0.75.

[0071] In yet another embodiment, the anode active material layer 104 is coated with a particulate lithium material selected from the group consisting of stabilized lithium metal particles, such as lithium carbonate stabilized lithium metal powder, lithium silicate stabilized lithium metal powder, or other sources of stabilized lithium metal powder or ink. The particulate lithium material is coated with a concentration of about 0.05 mg / cm. 2 ~5mg / cm 2 , for example, about 0.1 mg / cm 2 ~4mg / cm 2 , or even about 0.5 mg / cm 2 ~3mg / cm 2 The lithium particulate material may be applied onto the anode active material layer 104 by spraying, filling, or otherwise disposing it on the anode active material layer 104 at a loading of about 1000 μm. 50The average particle size (D) can be from 5 μm to 200 μm, for example, from about 10 μm to 100 μm, from 20 μm to 80 μm, or even from about 30 μm to 50 μm. 50 ) can be defined as the particle size corresponding to 50% on the cumulative volume-based particle size distribution curve. 50 ) can be measured, for example, using laser diffraction methods.

[0072] In one embodiment, the anode current collector 202 has an electrical conductance that is substantially greater than the electrical conductance of its associated anode active material layer 104. For example, in one embodiment, when there is an applied current to store energy in the secondary battery 100 or an applied load to discharge the secondary battery 100, the ratio of the electrical conductance of the anode current collector 202 to the electrical conductance of the anode active material layer 104 is at least 100:1. By way of further example, in some embodiments, when there is an applied current to store energy in the secondary battery 100 or an applied load to discharge the secondary battery 100, the ratio of the electrical conductance of the anode current collector 202 to the electrical conductance of the anode active material layer 104 is at least 500:1. By way of further example, in some embodiments, when there is an applied current to store energy in the secondary battery 100 or an applied load to discharge the secondary battery 100, the ratio of the electrical conductance of the anode current collector 202 to the electrical conductance of the anode active material layer 104 is at least 1000:1. By way of further example, in some embodiments, when there is an applied current to store energy in the secondary battery 100 or an applied load to discharge the secondary battery 100, the ratio of the electrical conductance of the anode current collector 202 to the electrical conductance of the anode active material layer 104 is at least 5000:1. By way of further example, in some embodiments, when there is an applied current to store energy in the secondary battery 100 or an applied load to discharge the secondary battery 100, the ratio of the electrical conductance of the anode current collector 202 to the electrical conductance of the anode active material layer 104 is at least 10,000:1.

[0073] FIG. 4 illustrates one of the anode structures 207 of FIG. 2 in an exemplary embodiment. Each anode structure 207 is aligned along the longitudinal axis (A E ) measured along the length (L E ) and width (W E ) and length L E and width W E The height (H E ) and.

[0074] Overall length L of anode structure 207 E will vary depending on the secondary battery 100 and its intended use. In general, however, the anode structure 207 typically has an overall length L in the range of about 5 millimeters (mm) to about 500 mm. E For example, in one such embodiment, the anode structure 207 has a total length L of about 10 mm to about 250 mm. E By way of further example, in one such embodiment, the anode structure 207 has a total length L of about 25 mm to about 100 mm. E According to one embodiment, the anode structure 207 includes one or more first electrode members having a first length and one or more second electrode members having a second length different from the first length. In yet another embodiment, the different lengths of the one or more first electrode members and the one or more second electrode members may be selected to conform to a predetermined shape of the secondary battery 100, such as a shape having different lengths along one or more of the longitudinal and / or lateral axes, and / or to provide predetermined performance characteristics of the secondary battery 100.

[0075] Width W of anode structure 207 E will vary depending on the secondary battery 100 and its intended use. In general, however, each anode structure 207 typically has a width W E For example, in one embodiment, each anode structure 207 has a width W E By way of further example, in one embodiment, the width W of each anode structure 207 ranges from about 0.025 mm to about 2 mm. Eis in the range of about 0.05 mm to about 1 mm. According to one embodiment, the anode structure 207 includes one or more first electrode members having a first width and one or more second electrode members having a second width different from the first width. In yet another embodiment, the different widths of the one or more first electrode members and the one or more second electrode members may be selected to conform to a predetermined shape of the secondary battery 100, such as a shape having different widths along one or more of the longitudinal and / or lateral axes, and / or to provide predetermined performance characteristics of the secondary battery 100.

[0076] Height H of anode structure 207 E will vary depending on the secondary battery 100 and its intended use. In general, however, the anode structure 207 typically has a height H in the range of about 0.05 mm to about 25 mm. E For example, in one embodiment, each anode structure 207 has a height H E By way of further example, in one embodiment, the height H of each anode structure 207 ranges from about 0.05 mm to about 5 mm. E is in the range of about 0.1 mm to about 1 mm. According to one embodiment, the anode structure 207 includes one or more first electrode members having a first height and one or more second electrode members having a second height different from the first height. In yet another embodiment, the different heights of the one or more first electrode members and the one or more second electrode members may be selected to conform to a predetermined shape of the secondary battery 100, such as a shape having different heights along one or more of the longitudinal and / or lateral axes, and / or to provide predetermined performance characteristics of the secondary battery 100.

[0077] Generally, the anode structures 207 each have a width W E and its height H E A length L substantially larger than each of E For example, in one embodiment, for each anode structure 207, L E and W E and H E and each of the L E and W Eand L are at least 5:1, respectively. E and H E and W are each at least 5:1. E and H E L for each E is at least 10:1. By way of further example, in one embodiment, W E and H E L for each E is at least 15:1. By way of further example, in one embodiment, W E and H E L for each E is at least 20:1 for each anode structure 207.

[0078] In one embodiment, the width W of the anode structure 207 E Height H E and H are each at least 0.4:1. E Against W E is at least 2:1, respectively, for each anode structure 207. By way of further example, in one embodiment, H E Against W E and H are each at a ratio of at least 10:1. E Against W E The ratio of H to H is at least 20:1, respectively. E Against W E The ratio of H is generally less than 1,000:1, respectively. For example, in one embodiment, E Against W E and H are each less than 500:1. E Against W E The ratio of H to H is less than 100:1, respectively. E Against W E and H are each less than 10:1. E Against W E The ratio ranges from about 2:1 to about 100:1 for each anode structure 207, respectively.

[0079] Separator structure, separator material, and electrolyte Referring again to FIG. 2, separator layer(s) 108 separate the cathode structure 206 from the anode structure 207. The separator layer 108 is made of an electrically insulating but ionically permeable separator material. The separator layer 108 is adapted to electrically insulate each member of the plurality of cathode structures 206 from each member of the plurality of anode structures 207. Each separator layer 108 will typically comprise a microporous separator material that can be permeated with a non-aqueous electrolyte; for example, in one embodiment, the microporous separator material comprises pores having diameters of at least 50 angstroms (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% to 55%.

[0080] Generally, the separator layers 108 each have a thickness of at least about 4 μm. For example, in one embodiment, the separator layers 108 have a thickness of at least about 8 μm. By way of further example, in one such embodiment, the separator layers 108 have a thickness of at least about 12 μm. By way of further example, in one such embodiment, the separator layers 108 have a thickness of at least about 15 μm. In some embodiments, the separator layers 108 have a thickness of up to 25 μm, up to 50 μm, or any other suitable thickness. Typically, however, the separator layers 108 have a thickness of less than about 12 μm or less than about 10 μm.

[0081] In general, the material of the separator layer 108 can be selected from a wide range of materials capable of conducting carrier ions between the anode active material layer 104 and the cathode active material layer 106 of the unit cell 200. For example, the separator layer 108 can include a microporous separator material capable of being permeated with a liquid non-aqueous electrolyte. Alternatively, the separator layer 108 can include a gel or solid electrolyte capable of conducting carrier ions between the anode active material layer 104 and the cathode active material layer 106 of the unit cell 200.

[0082] In one embodiment, the separator layer 108 may include a polymer-based electrolyte. Exemplary polymer electrolytes include PEO-based polymer electrolytes, polymer-ceramic composite electrolytes, polymer-ceramic composite electrolytes, and polymer-ceramic composite electrolytes.

[0083] In another embodiment, the separator layer 108 may include an oxide-based electrolyte. An exemplary oxide-based electrolyte is lithium lanthanum titanate (Li 0.34 La 0.56 TiO3), Al-doped lanthanum zirconate lithium (Li 6.24 La3Zr2Al 0.24 O 11.98 ), Ta-doped lithium lanthanum zirconate (Li 6.4 La3Zr 1.4 Ta 0.6 O 12 ), and lithium aluminum titanium phosphate (Li 1.4 Al 0.4 Ti 1.6 (PO4)3).

[0084] In another embodiment, the separator layer 108 may include a solid electrolyte. An exemplary solid electrolyte is lithium tin sulfide (Li 10 SnP2S 12 ), lithium phosphorus sulfide (β-Li3PS4) and lithium phosphorus sulfide chloride iodide (Li6PS5Cl 0.9 I 0.1 ) and other sulfide-based electrolytes.

[0085] In some embodiments, the separator layer 108 may include a solid lithium-ion conducting ceramic, such as a lithium-filled garnet.

[0086] In one embodiment, the separator layer 108 comprises a microporous separator material including a particulate material and a binder, the microporous separator material having a porosity of at least about 20% by volume. The pores of the microporous separator material have a diameter of at least 50 Å, typically in the range of about 250 Å to about 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% by volume. In one embodiment, the microporous separator material has a porosity of about 35 to 55%.

[0087] Binders for the microporous separator material 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, calcium hydroxide, etc. For example, in one embodiment, the binder is a fluoropolymer derived from monomers containing vinylidene fluoride, hexafluoropropylene, tetrafluoropropene, etc. In another embodiment, the binder is a polyolefin such as polyethylene, polypropylene, or polybutene having any of a range of molecular weights and densities. 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, and polyethylene oxide. In another embodiment, the binder is selected from the group consisting of acrylates, styrenes, epoxies, and silicones, hi another embodiment, the binder is a copolymer or blend of two or more of the foregoing polymers.

[0088] The particulate material comprised by the microporous separator material may also be selected from a wide range of materials. Generally, such materials have relatively low electronic 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 has a density 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 -5 By way of further example, in one embodiment, the particulate material has a carrier ion conductivity of less than 1×10 -6 The conductive material has a carrier ion conductivity of less than S / cm. Exemplary particulate materials include particulate polyethylene, polypropylene, TiO2-polymer composite, silica aerogel, fumed silica, silica gel, silica hydrogel, silica cellogel, silica sol, colloidal silica, alumina, titanium, 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 particulate oxides or nitrides such as TiO2, SiO2, Al2O3, GeO2, B2O3, Bi2O3, BaO, ZnO, ZrO2, BN, Si3N4, and Ge3N4. See, for example, P. Arora and J. Zhang, "Battery Separators," Chemical Reviews 2004, 104, 4419-4462. In one embodiment, the particulate material has an average particle size of about 20 nm to 2 μm, more typically 200 nm to 1.5 μm. In one embodiment, the particulate material has an average particle size of about 500 nm to 1 μm.

[0089] In alternative embodiments, the particulate materials comprised by the microporous separator material may be bound by techniques such as sintering, bonding, curing, etc., while maintaining a desired porosity for electrolyte infiltration to provide ionic conductivity for the functioning of the battery.

[0090] In secondary battery 100 (see FIG. 1), the microporous separator material of separator layer 108 is infiltrated with a non-aqueous electrolyte suitable for use as a 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 LiClO4, LiBF4, LiPF6, LiAsF6, LiCl, and LiBr, as well as inorganic lithium salts such as LiB(C6H5)4, LiN(SO2CF3)2, LiN(SO2CF3)3, LiNSO2CF3, LiNSO2CF5, LiNSO2C4F9, LiNSO2C5F 11 , LiNSO2C6F 13 , and LiNSO2C7F 15 Exemplary organic solvents for dissolving lithium salts include cyclic esters, chain esters, cyclic ethers, and chain ethers. Specific examples of cyclic esters include propylene carbonate, butylene carbonate, γ-butyrolactone, vinylene carbonate, 2-methyl-γ-butyrolactone, acetyl-γ-butyrolactone, and γ-valerolactone. Specific examples of chain 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, alkyl tetrahydrofuran, dialkyl tetrahydrofuran, alkoxy tetrahydrofuran, dialkoxy tetrahydrofuran, 1,3-dioxolane, alkyl-1,3-dioxolane, and 1,4-dioxolane. Specific examples of chain ethers include 1,2-dimethoxyethane, 1,2-diethoxyethane, diethyl ether, ethylene glycol dialkyl ethers, diethylene glycol dialkyl ethers, triethylene glycol dialkyl ethers, and tetraethylene glycol dialkyl ethers.

[0091] Additional Embodiments of the Disclosure Because cathode active materials such as lithium cobalt oxide are relatively stable in ambient air (e.g., they resist oxidation) compared to lithiated anode materials such as lithiated graphite, when a secondary battery is assembled, an amount of carrier ions available for circulation between the anode and cathode is often initially provided at the cathode. When the secondary battery is charged for the first time, carrier ions are extracted from the cathode and introduced into the anode. As a result, the anode potential drops significantly (towards the potential of the carrier ions) and the cathode potential rises (to become more positive). These potential changes can cause parasitic reactions at both the cathode and anode, but sometimes more severely at the anode. For example, decomposition products containing lithium (or other carrier ions) and electrolyte components, known as solid electrolyte interfaces (SEIs), can easily form on the surface of carbon anodes. These surfaces or coating layers are carrier ion conductors and establish ionic bonds between the anode and the electrolyte, preventing the reaction from proceeding further.

[0092] Although the formation of the SEI layer is desirable for the stability of the half-cell system including the anode and electrolyte, a portion of the carrier ions introduced into the cell through the cathode are irreversibly bound and therefore removed from the cycling operation, i.e., from the capacity available to the user. As a result, during the initial discharge, fewer carrier ions are transferred back from the anode to the cathode than were initially provided by the cathode during the initial charging operation, resulting in irreversible capacity loss. During each subsequent charge and discharge cycle, the capacity loss resulting from mechanical and / or electrical degradation to the anode and / or cathode tends to be much less per cycle, but even the relatively small carrier ion losses per cycle contribute significantly to the reduction in energy density and cycle life as the battery ages. In addition, chemical and electrochemical degradation can also occur on the electrodes, causing capacity loss. To compensate for the formation of the SEI (or another carrier ion consumption mechanism, such as mechanical and / or electrical degradation of the negative electrode), additional or supplemental carrier ions can be provided from an auxiliary electrode after the formation of the battery.

[0093] In general, the positive electrode 208 of the secondary battery 100 (e.g., the population of negative electrode structures 206 in the secondary battery 100) preferably has a reversible coulombic capacity that matches the discharge capacity of the negative electrode 209 (e.g., the population of anode structures 207 in the secondary battery 100). Stated another way, the positive electrode 208 of the secondary battery 100 is sized to have a reversible coulombic capacity that corresponds to the discharge capacity of the negative electrode 209, which is a function of the end-of-discharge voltage of the negative electrode 209.

[0094] In some embodiments, the negative electrode 209 of the secondary battery 100 (e.g., the collective collection of positive electrode structures 207 in the secondary battery 100) is designed to have a reversible coulombic capacity that exceeds the reversible coulombic capacity of the positive electrode 208. For example, in one embodiment, the ratio of the reversible coulombic capacity of the negative electrode 209 to the reversible coulombic capacity of the positive electrode 208 is at least 1.2:1, respectively. As a further example, in one embodiment, the ratio of the reversible coulombic capacity of the negative electrode 209 to the reversible coulombic capacity of the positive electrode 208 is at least 1.3:1, respectively. As a further example, in one embodiment, the ratio of the reversible coulombic capacity of the negative electrode 209 to the reversible coulombic capacity of the positive electrode 208 is at least 2:1, respectively. As a further example, in one embodiment, the ratio of the reversible coulombic capacity of the negative electrode 209 to the reversible coulombic capacity of the positive electrode 208 is at least 3:1, respectively. As a further example, the ratio of the reversible coulombic capacity of the negative electrode 209 to the reversible coulombic capacity of the positive electrode 208 is at least 4:1, respectively. As a further example, the ratio of the reversible coulombic capacity of the negative electrode 209 to the reversible coulombic capacity of the positive electrode 208 is at least 5:1, respectively. Advantageously, the excess coulombic capacity of the negative electrode 209 provides a source of positive electrode active material that allows the secondary battery 100 to operate reversibly within certain voltages that inhibit the formation of crystalline phases (which incorporate carrier ions) on the negative electrode 209 that reduce the cycle life of the negative electrode 209 as a result of cycling.

[0095] As mentioned above, the formation of the SEI during the initial charge / discharge cycles reduces the amount of carrier ions available for reversible cycling. Mechanical and / or electrical degradation of the negative electrode 209 during cycling of the secondary battery 100 may further reduce the amount of carrier ions available for reversible cycling. Therefore, to compensate for the formation of the SEI (or another carrier ion consumption mechanism such as mechanical and / or electrical degradation of the negative electrode), additional or supplemental carrier ions can be provided from an auxiliary electrode after formation of the secondary battery 100. In an embodiment of the present disclosure, the auxiliary electrode is used to electrochemically transfer additional carrier ions to the positive electrode 208 and / or negative electrode 209 of the secondary battery 100 during and / or after formation. In one embodiment, the auxiliary electrode is removed after transferring additional carrier ions to the secondary battery 100 to improve the energy density of the final form of the secondary battery.

[0096] FIG. 5 is a perspective view of an exemplary embodiment of a buffer system 500, and FIG. 6 is an exploded view of the buffer system 500. In general, the buffer system 500 can be temporarily assembled during or after the initial formation of the secondary battery 100, and the buffer system 500 is used to introduce additional carrier ions to the positive electrode 208 and / or negative electrode 209 of the secondary battery 100 using an auxiliary pole 502 (see FIG. 6). In this embodiment, the buffer system 500 includes an enclosure 504 that encapsulates the auxiliary pole 502 (see FIG. 6) and the secondary battery 100 within the periphery 506 of the enclosure 504. In FIG. 5, the electrical terminals 124, 125 of the secondary battery 100 and a segment of the conductive tab 508-1 extend from the periphery 506 of the enclosure 504 and provide electrical connection to the auxiliary pole 502 and the secondary battery 100. In this embodiment, the enclosure 504 includes a first enclosure layer 510 and a second enclosure layer 511 joined together to form the enclosure 504 .

[0097] 6, the first enclosure layer 510 has a perimeter 512 and the second enclosure layer 511 has a perimeter 513. Each of the enclosure layers 510, 511 may include a flexible or semi-flexible material, such as aluminum, a polymer, a thin flexible metal, or the like. In one embodiment, one or more of the enclosure layers 510, 511 includes a multi-layer aluminum polymer material, plastic, or the like. In another embodiment, one or more of the enclosure layers 510, 511 includes a polymer material laminated on a metal substrate, such as aluminum. In one embodiment, the first enclosure layer 510 includes a pouch 514 (e.g., a recess) that is sized and shaped to match the exterior size and shape of the secondary battery 100.

[0098] The auxiliary pole 502 partially surrounds the secondary battery 100 in the buffer system 500 and includes a source of carrier ions to replenish the lost energy capacity of the secondary battery 100 after formation (i.e., to compensate for the loss of carrier ions during the formation of the SEI and other carrier ion losses during the first charge and / or discharge cycle of the secondary battery 100). In an embodiment, the auxiliary pole 502 may include a foil of carrier ions in metallic form (e.g., a foil of lithium, magnesium, or aluminum) or any of the aforementioned materials used for the cathode active material layer 106 and / or anode active material layer 104 (see FIG. 2) in a carrier ion-containing form. For example, the auxiliary pole 502 may include lithiated silicon or a lithiated silicon alloy. When the buffer system 500 is assembled, the combination of the auxiliary pole 502, which may be referred to as an auxiliary subassembly 516 (see FIG. 6), and the secondary battery 100 is inserted into the pouch 514, and the enclosure layers 510, 511 are sealed together to form the buffer system 500 as depicted in FIG. 5. Specific details of the assembly process of the buffer system 500 and how the buffer system 500 is used during the carrier ion transfer process to the secondary battery 100 are discussed in more detail below. The auxiliary pole 502 in this embodiment includes a conductive tab 508, which may be segmented, for example, for ease of manufacturing, into a conductive tab 508-2 covered by the enclosure 504 and a conductive tab 508-1 partially exposed by the enclosure, as depicted in FIG. 5.

[0099] Fig. 7 is a perspective view of an auxiliary electrode 502 according to an embodiment of the present invention, and Fig. 8 is an exploded perspective view of the auxiliary electrode. Referring to Fig. 7, the auxiliary electrode 502 includes a separator 702 covering a conductive layer 704 and a carrier ion supply layer 706. When the auxiliary electrode 502 is formed into the shape depicted in Fig. 6, the carrier ion supply layer 706 is disposed adjacent to the main surfaces 126, 127 (see Fig. 1) of the secondary battery 100, and the separator 702 insulates the casing 116 of the secondary battery 100 from the conductive layer 704 and the carrier ion supply layer 706. The separator 702 includes an electrolyte, which facilitates the movement of carrier ions from the carrier ion supply layer 706 to the secondary battery 100 during the buffering process.

[0100] 8, the auxiliary electrode 502 includes, from bottom to top in FIG. 8, a collection of a separator 702, a conductive layer 704, and a carrier ion supply layer 706. The auxiliary electrode 502 in this embodiment further includes a conductive tab 508-2, which is conductive and electrically coupled to the conductive layer 704. The conductive tab 508-2 provides an electrical connection to the auxiliary electrode 502. Generally, the auxiliary electrode 502 is used during a buffer process to transfer carrier ions from the carrier ion supply layer 706 to the positive electrode 208 and / or negative electrode 209 of the secondary battery 100 during or after formation of the secondary battery 100.

[0101] The separator 702 may include any of the materials described above with respect to the separator layer 108 of the secondary battery 100. The separator 702 may be impregnated with an electrolyte that provides a medium for conducting carrier ions from the carrier ion supply layer 706 to the positive electrode 208 of the secondary battery 100 and / or the negative electrode 209 of the secondary battery. The electrolyte may include any of the materials described above with respect to the secondary battery 100.

[0102] The separator 702 in this embodiment includes a first surface 802 and a second surface 803 opposite the first surface 802. The surfaces 802, 803 of the separator 702 form the main surface of the separator 702 and are disposed in the XY plane of FIG. 8. The separator 702 in this embodiment has a width 804 extending in the direction of the Y axis. The separator 702 in this embodiment is segmented in the width 804 into a first portion 805 and a second portion 806. In some embodiments, the separator 702 can include a first separator layer 702-1 corresponding to the first portion 805 and a second separator layer 702-2 corresponding to the second portion 806.

[0103] In one embodiment, the width 804 of the separator 702 is about 34 mm. In other embodiments, the width 804 of the separator is about 30 mm, about 35 mm, or another suitable value. In some embodiments, the width 804 of the separator 702 is within a range of values ​​from about 10 mm to about 200 mm, or any other suitable range that enables the separator 702 to function as described herein.

[0104] The separator 702, in one embodiment, has a length 808 that extends in the direction of the X-axis. In one embodiment, the length 808 of the separator 702 is about 72 mm. In other embodiments, the length 808 of the separator 702 is about 65 mm, about 70 mm, about 75 mm, or any other suitable value that enables the separator 702 to function as described herein. In some embodiments, the length 808 of the separator 702 is within a range of values ​​from about 30 mm to about 200 mm, or any other suitable range of values ​​that enables the separator 702 to function as described herein.

[0105] In one embodiment, the separator 702 has a thickness 810 extending in the direction of the Z-axis. Generally, the thickness 810 is the distance from the first surface 802 of the separator 702 to (and including) the second surface 803 of the separator. In one embodiment, the thickness 810 of the separator 702 is about 0.025 mm. In other embodiments, the thickness 810 of the separator 702 is about 0.015 mm, about 0.02 mm, about 0.03 mm, about 0.035 mm, or some other suitable value. In some embodiments, the thickness 810 of the separator 702 is within a range of values ​​from about 0.01 mm to about 1.0 mm, or some other suitable range of values ​​that enables the separator 702 to function as described herein.

[0106] The conductive layer 704 is electrically conductive and may include a metal, a metallized film, an insulating base material to which a conductive material is applied, or some other type of conductive material. In some embodiments, the conductive layer 704 includes copper. In other embodiments, the conductive layer 704 includes aluminum or another metal. In this embodiment, the conductive layer 704 is electrically coupled to a conductive tab 508-2, which is also electrically conductive. The conductive tab 508-2 has a first end 812 disposed proximate to the conductive layer 704 and a second end 813 disposed distally of the conductive layer 704 opposite the first end 812. The first end 812 of the conductive tab 508-2 is electrically coupled to the conductive layer 704. In some embodiments, the first end 812 of the conductive tab 508-2 is spot welded to the conductive layer 704. In other embodiments, the first end 812 of the conductive tab 508-2 is soldered to the conductive layer 704. In general, the conductive tab 508-2 may be affixed to the conductive layer 704 at the first end 812 using any suitable means that ensures a mechanical and electrical connection to the conductive layer. The conductive tab 508-2 may comprise any type of conductive material as desired. In one embodiment, the conductive tab 508-2 comprises a metal. In these embodiments, the conductive tab 508-2 may comprise nickel, copper, aluminum, or other suitable metal or metal alloy that enables the conductive tab 508-2 to function as described herein.

[0107] The conductive layer 704 in this embodiment includes a first surface 814 and a second surface 815 opposite the first surface 814. The surfaces 814, 815 of the conductive layer 704 form the major surfaces of the conductive layer 704 and are disposed in the XY plane of FIG. 8. The conductive layer 704 in this embodiment has a width 816 that extends in the direction of the Y axis. In one embodiment, the width 816 of the conductive layer 704 is about 15 mm. In other embodiments, the width 816 of the conductive layer 704 is about 10 mm, about 20 mm, or any other suitable value that enables the conductive layer 704 to function as described herein.

[0108] In some embodiments, the width 816 of the conductive layer 704 is within a range of values ​​from about 5 mm to about 100 mm, or any other suitable range of values ​​that enables the conductive layer 704 to function as described herein. The first surface 814 of the conductive layer 704 in this embodiment is segmented into a first region 818-1 disposed proximate a first end 820 of the conductive layer 704, a second region 818-2 disposed proximate a second end 821 of the conductive layer 704, and a third region 818-3 disposed between the first region 818-1 and the second region 818-2.

[0109] The conductive layer 704 has a length 822 that extends in the direction of the X-axis. In one embodiment, the length 822 of the conductive layer 704 is about 70 mm. In other embodiments, the length 822 of the conductive layer 704 is about 60 mm, about 65 mm, about 75 mm, or some other suitable value that enables the conductive layer 704 to function as described herein. In some embodiments, the length 822 of the conductive layer 704 is within a range of values ​​from about 30 mm to about 200 mm, or some other suitable range of values ​​that enables the conductive layer 704 to function as described herein.

[0110] The conductive layer 704 has a thickness 824 extending in the direction of the Z-axis. Generally, the thickness 824 is the distance from the first surface 814 of the conductive layer 704 to (and including) the second surface 815 of the conductive layer 704. In one embodiment, the thickness 824 of the conductive layer 704 is about 0.1 mm. In other embodiments, the thickness 824 of the conductive layer 704 is about 0.005 mm, about 0.15 mm, or about 0.2 mm. In some embodiments, the thickness 824 of the conductive layer 704 is within a range of values ​​from about 0.01 mm to about 1.0 mm, or any other suitable range of thicknesses that enable the conductive layer 704 to function as described herein.

[0111] In one embodiment, the carrier ion supply layer 706, which includes a population of carrier ion supply layers 706, includes any of the carrier ion containing materials described above that may be utilized to supply carrier ions to the positive electrode 208 and / or negative electrode 209 of the secondary battery 100. The carrier ion supply layer 706 may include one or more sources of lithium ions, sodium ions, potassium ions, calcium ions, magnesium ions, and aluminum ions. In this embodiment, the carrier ion supply layer 706 is disposed in a first region 818-1 and a second region 818-2 of the conductive layer 704. In some embodiments, the carrier ion supply layer 706 is also disposed in a third region 818-3 of the conductive layer 704.

[0112] The carrier ion supply layer 706 in this embodiment has a first surface 826 and a second surface 827 opposite the first surface 826. The surfaces 826, 827 of the carrier ion supply layer 706 form the major surfaces of the carrier ion supply layer 706 and are disposed in the XY plane of FIG. 8. The carrier ion supply layer 706 in this embodiment has a width 828 extending in the direction of the Y axis. In one embodiment, the width 828 of the carrier ion supply layer 706 is about 15 mm. In other embodiments, the width 828 of the carrier ion supply layer 706 is about 10 mm, about 20 mm, or any other suitable value that enables the carrier ion supply layer 706 to function as described herein. In some embodiments, the width 828 of the carrier ion supply layer 706 is within a range of values ​​between about 5 mm and about 100 mm, or any other suitable range of values ​​that enables the carrier ion supply layer 706 to function as described herein.

[0113] The carrier ion supply layer 706, in one embodiment, has a length 830 extending in the direction of the X-axis. In one embodiment, the length 830 of the carrier ion supply layer 706 is about 23 mm. In other embodiments, the length 830 of the carrier ion supply layer 706 is about 15 mm, about 20 mm, about 25 mm, or any other suitable length that enables the carrier ion supply layer 706 to function as described herein. In some embodiments, the length 830 of the carrier ion supply layer 706 is within a range of values ​​from about 10 mm to about 100 mm, or any other suitable range of values ​​that enables the carrier ion supply layer 706 to function as described herein.

[0114] The carrier ion supply layer 706 has a thickness 832 extending in the direction of the Z-axis. Generally, the thickness 832 is the distance between a first surface 826 of the carrier ion supply layer 706 and a second surface 827 of the carrier ion supply layer 706. In one embodiment, the thickness 832 of the carrier ion supply layer 706 is about 0.13 mm. In other embodiments, the thickness 832 of the carrier ion supply layer 706 is about 0.005 mm, about 0.15 mm, or about 0.2 mm. In some embodiments, the thickness 832 of the carrier ion supply layer 706 is within a range of values ​​between about 0.01 mm and about 1.0 mm, or any other suitable range of values ​​for the thickness 832 that enables the carrier ion supply layer 706 to function as described herein.

[0115] In this embodiment, the carrier ion supply layers 706 are separated from one another by a distance 834 that corresponds to the third region 818-3. In one embodiment, the distance 834 is about 23 mm. In other embodiments, the distance 834 is about 15 mm, about 20 mm, about 25 mm, or about 30 mm. In some embodiments, the distance 834 is within a range of values ​​from about 10 mm to about 50 mm, or any other suitable range of values ​​that enables the carrier ion supply layers 706 to function as described herein.

[0116] In one embodiment, the carrier ion supply layer 706 is sized to provide at least 15% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100. For example, in one such embodiment, the carrier ion supply layer 706 is sized to contain sufficient carrier ions (e.g., lithium, magnesium, or aluminum ions) to provide at least 30% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100. By way of further example, in one such embodiment, the carrier ion supply layer 706 is sized to include sufficient carrier ions to provide at least 100% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100. By way of further example, in one such embodiment, the carrier ion supply layer 706 is sized to include sufficient carrier ions to provide at least 200% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100. By way of further example, in one such embodiment, the carrier ion supply layer 706 is sized to include sufficient carrier ions to provide at least 300% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100. By way of further example, in one such embodiment, the carrier ion supply layer 706 is sized to include sufficient carrier ions to provide between about 100% and about 200% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100.

[0117] During the assembly process of the auxiliary pole 502, the separator 702 may be cut from stock material or may be prefabricated to achieve the width 804 and length 808 as shown in FIG. 8. The conductive layer 704 may be cut from stock material or may be prefabricated to achieve the width 816 and length 822 shown in FIG. 8. In some embodiments, the conductive layer 704 is prefabricated to include a conductive tab 508-2 having a first end 812 mechanically and electrically affixed to the conductive layer 704 as depicted in FIG. 8. In other embodiments, the conductive tab 508-2 is cut from stock material and mechanically and electrically coupled to the conductive layer 704 (e.g., by spot welding or soldering the first end 812 to the conductive layer 704). In some embodiments, the carrier ion supply layer 706 is cut to size from a stock material and bonded or otherwise laminated to the conductive layer 704 (e.g., by cold welding the carrier ion supply layer 706 onto the conductive layer 704) to achieve the orientation depicted in Figure 8, with the second surface 827 of the carrier ion supply layer 706 in contact with the first surface 814 of the conductive layer 704. For example, the material (e.g., lithium) used to form the carrier ion supply layer 706 may be present in stock form as a roll of lithium sheets cut to size.

[0118] In another embodiment, the conductive layer 704 is prefabricated to include a carrier ion supply layer 706 arranged in the orientation depicted in Figure 8. In this embodiment, the conductive layer 704 is disposed within the first portion 805 of the separator 702 along the X-axis, and the second surface 815 of the conductive layer 704 contacts the first surface 802 of the separator 702.

[0119] 9 is a perspective view of the auxiliary pole 502 at an intermediate stage in the fabrication process of the auxiliary pole. At this stage, the conductive layer 704 is disposed on the first portion 805 of the separator 702, and the conductive tab 508-2 extends from a first end 812 attached to the conductive layer 704 to the left (Y-axis direction) of FIG. 9 , away from the separator 702 and the conductive layer 704, toward a second end 813. The first surface 802 of the separator 702 is covered by the conductive layer 704 in the first portion 805 of the separator 702, while the first surface 802 of the separator remains uncovered in the second portion 806 of the separator 702.

[0120] To continue the fabrication process of the auxiliary pole 502, in one embodiment, the second portion 806 of the separator 702 is folded in the direction of the left-facing arrow 902 in FIG. 9 (around an axis parallel to the X-axis) such that the first surface 802 in the second portion 806 of the separator 702 contacts the first surface 826 of the carrier ion supply layer 706 and the first surface 814 of the conductive layer 704 exposed between the carrier ion supply layers 706. If the separator 702 includes a first separator layer 702-1 and a second separator layer 702-2, the second separator layer may be positioned such that the first surface 802 of the second separator layer contacts the first surface 826 of the carrier ion supply layer 706 and the first surface 814 of the conductive layer 704 exposed between the carrier ion supply layers 706.

[0121] 10 is a perspective view of the auxiliary pole 502 at another intermediate stage of the fabrication process after folding the second portion 806 of the separator 702 as described above. At this stage, the separator 702 encapsulates the conductive layer 704 and the carrier ion supply layer 706, leaving a portion between the first end 812 of the conductive tab 508-2 and the second end 813 of the conductive tab 508-2 uncovered by the separator 702. The separator 702 can then be bonded to itself along at least a portion of the separator's periphery 1002 to encapsulate the conductive layer 704 within the separator's first portion 805 and the separator's second portion 806 along the separator's first surface 802 (not visible in FIG. 10).

[0122] In one embodiment, the separator 702 is bonded to itself along at least a portion of the separator's periphery 1002 using a hot melt process, a welding process, a bonding process, or the like. In FIG. 10, the auxiliary pole 502 at this stage includes a first side 1004 and a second side 1005 opposite the first side 1004. The first side 1004 includes a second surface 803 of the separator 702 that covers the carrier ion supply layer 706 in a first region 818-1 adjacent the first end 820 (not visible in FIG. 10) of the conductive layer 704 and in a second region 818-2 adjacent the second end 821 (not visible in this view) of the conductive layer 704. 10, the first region 818-1 is proximate to the first end 812 of the conductive tab 508-2 and the second region 818-2 is disposed away from the first end 812 of the conductive tab 508-2. The first end 812 of the conductive tab 508-2 is electrically coupled to the conductive layer 704 in a third region 818-3 of the conductive layer 704. In some embodiments, the conductive tab 508 may be extended (e.g., with the conductive tab 508-1 as shown in FIG. 11, which depicts the assembled auxiliary pole 502).

[0123] Implementing a fabrication process for the buffer system 500 (see FIGS. 6 and 7) in response to fabrication of the auxiliary pole 502 continues as follows. FIGS. 12-16 are perspective views of the buffer system 500 at various stages of the fabrication process. Referring to FIG. 12, the second region 818-2 of the auxiliary pole 502 is inserted into the pouch 514 of the first enclosure layer 510, the second side 1005 of the auxiliary pole is disposed within the pouch 514 toward the first enclosure layer 510, and the first side 1004 of the auxiliary pole is disposed within the pouch 514 away from the first enclosure layer 510. The third region 818-3 and the first region 818-1 of the auxiliary pole 502 extend away from the pouch 514 along the Y-axis direction.

[0124] With the auxiliary pole 502 oriented in the pouch 514 as depicted in FIG. 12, the secondary battery 100 is placed on the auxiliary pole 502 in the pouch 514 corresponding to the second region 818-2 of the auxiliary pole 502 (see FIG. 13). In this embodiment, the first major surface 126 (see FIG. 1, not visible in FIG. 13) of the secondary battery 100 contacts the auxiliary pole 502 in the pouch 514, and the second major surface 127 of the secondary battery is disposed away from the auxiliary pole 502. The electrical terminals 124, 125 of the secondary battery 100 extend away from the pouch 514 in the Y-axis direction of FIG. 13, positioning the electrical terminals outside the perimeter 512 of the first enclosure layer 510. At this stage in the fabrication process of the buffer system 500, in one embodiment, an electrolyte is added to the pouch 514. In another embodiment, the separator 702 of the auxiliary pole 502 is pre-impregnated with the electrolyte.

[0125] With the secondary battery 100 loaded onto the second region 818-2 of the auxiliary pole 502 in the pouch 514, the auxiliary pole 502 is folded in the direction of the arrow 1302 to place the first side 1004 of the first region 818-1 of the auxiliary pole 502 in contact with the second main surface 127 of the secondary battery 100, as depicted in FIG. 14. In this configuration, both main surfaces 126, 127 of the secondary battery 100 (see FIG. 1) are electrochemically bonded to the carrier ion supply layer 706 of the auxiliary pole 502 using the separator 702 (see FIGS. 7-11) and an electrolyte disposed between each of the main surfaces 126, 127 of the secondary battery 100 and the carrier ion supply layer 706.

[0126] FIG. 15 is a cross-sectional view of the buffer system 500 taken along the line AA in FIG. 14. In this view, the layers of the buffer system 500 in the pouch 514 of the first enclosure layer 510 are visible. In particular, FIG. 15 illustrates the arrangement of the secondary battery 100 and the auxiliary pole 502 in the pouch 514, specifically, from top to bottom, the separator 702, the conductive layer 704, one of the carrier ion supply layers 706, the separator 702, and the second main surface 127 of the secondary battery 100 in the casing 116. FIG. 15 further illustrates the first enclosure layer 510, the separator 702, the conductive layer 704, one of the carrier ion supply layers 706, the separator 702, and the first main surface 126 of the secondary battery 100 in the casing 116, which are stacked in this order from bottom to top.

[0127] With the secondary battery 100 sandwiched by the auxiliary pole 502 within the pouch 514 as illustrated in FIG. 15, the second enclosure layer 511 is aligned to the first enclosure layer 510 as depicted in FIG. 16. After the second enclosure layer 511 is properly positioned relative to the first enclosure layer 510, the enclosure layers 510, 511 are sealed along a sealing line 1602 (shown by a dashed line in FIG. 16) to form the enclosure 504. The enclosure layers 510, 511 may be sealed along the sealing line 1602 by welding, heat sealing, adhesives, combinations thereof, and the like. In another embodiment, the enclosure layers 510, 511 can be sealed along three sides of the sealing line 1602 to form a pocket therein. In this embodiment, the secondary battery 100 can be placed within the pocket, and then the final edge of the sealing line 1602 is sealed. In one embodiment, the sealing line 1602 is sealed using a hot press, which applies a controlled temperature and pressure to the sealing line 1602 to bond or fuse the enclosure layers 510, 511 together along the sealing line 1602. In another embodiment, a vacuum is applied to the secondary battery 100 during the sealing process to evacuate any excess volume occupied by air or other gases. The time that the sealing line 1602 undergoes the hot press may be controlled and depends on the material selected for the enclosure layers 510, 511. When sealed over the secondary battery 100, the sealed enclosure layers 510, 511 form the buffer system 500. When sealed, the buffer system 500 is liquid-tight and / or air-tight, depending on the desired application. The electrical terminals 124 and 125 and the conductive tabs 508-1 of the secondary battery 100 remain exposed and are not covered by the enclosure layers 510, 511, allowing a subsequent buffering process to be applied to the secondary battery 100.

[0128] With the secondary battery 100 and the carrier ion supply layer 706 of the auxiliary pole 502 (not visible in FIG. 16 ) electrochemically bonded within the enclosure 504 of the buffer system 500, a carrier ion buffering process is performed on the secondary battery 100 during or after the initial formation of the secondary battery 100. Generally, this carrier ion buffering process transfers carrier ions from the carrier ion supply layer 706 of the auxiliary pole 502 to each of the first major surface 126 of the secondary battery 100 and the second major surface 127 of the secondary battery 100 (see FIG. 15 ). Generally, transferring carrier ions from both major surfaces 126, 127 of the secondary battery 100 to the secondary battery 100 as depicted in FIG. 15 provides the technical advantage that more carrier ions are loaded into the anode and / or cathode of the secondary battery 100, thereby distributing the forces generated by the expansion of the anode and / or cathode more evenly across the casing 116 of the secondary battery 100.

[0129] Either before or after inserting the secondary battery 100 into the buffer system 500, the secondary battery 100 is charged (e.g., via electrical terminals 124, 125) by transferring carrier ions from the secondary battery's cathode structure 206 to the secondary battery's anode structure 207. Charging may be interrupted when the secondary battery's positive electrode 208 reaches its end-of-charge design voltage. During the initial charging cycle, an SEI may form on the surface of the secondary battery's anode structure 207. To compensate for the loss of carrier ions to the SEI and to further provide additional carrier ions to mitigate long-term secondary reactions during cycling in which carrier ions are lost due to side reactions, the positive electrode 208 and / or negative electrode 209 of the secondary battery 100 can be replenished by applying a voltage across the auxiliary electrode 502 and the cathode structure 206 and / or anode structure 207 (e.g., via the conductive tab 508-1 of the auxiliary electrode 502 and one of the electrical terminals 124, 125) to drive carrier ions from the carrier ion supply layer 706 of the auxiliary electrode 502 to the cathode structure 206 and / or anode structure 207 of the secondary battery 100. Once the transfer of carrier ions from the auxiliary electrode 502 to the secondary battery 100 is completed, the negative electrode 209 of the secondary battery 100 is charged again by carrier ions that have now transferred from the cathode structure 206 of the secondary battery 100 to the anode structure 207 of the secondary battery.

[0130] In one embodiment, the amount of carrier ions transferred from the auxiliary electrode 502 to the secondary battery 100 during the buffering process is about 50% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100. In other embodiments, the amount of carrier ions transferred from the auxiliary electrode 502 to the secondary battery 100 during the buffering process is about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, or about 100% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100. In some embodiments, the amount of carrier ions transferred from the auxiliary electrode 502 to the secondary battery 100 is within a range of values ​​from about 1% to about 100% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100. In one particular embodiment, the negative electrode 209 of the secondary battery 100 has approximately 170% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100 stored as carrier ions when the secondary battery 100 is charged, and approximately 70% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100 stored as carrier ions when the secondary battery 100 is discharged. The excess carrier ions in the negative electrode 209 of the secondary battery 100 provided during the buffering process provides the technical advantage of mitigating the loss of carrier ions in the secondary battery 100 due to the SEI upon initial formation. Furthermore, the excess carrier ions in the negative electrode 209 of the secondary battery 100 provided during the buffering process provides the technical advantage of mitigating the loss of carrier ions in the secondary battery 100 due to side reactions that deplete carrier ions in the secondary battery 100 when the secondary battery 100 is cycled during use, which reduces the capacity loss of the secondary battery 100 over time.

[0131] In some embodiments, the transfer of carrier ions from the auxiliary electrode 502 to the secondary battery 100 may occur simultaneously with the initial formation of the secondary battery 100 (e.g., during a first charge of the secondary battery 100) and / or during a subsequent charge of the secondary battery 100 after the initial formation. In these embodiments, the carrier ions are transferred from the positive electrode 208 of the secondary battery 100 to the negative electrode 209 of the secondary battery 100. Simultaneously or based on a time delay or pattern, the carrier ions are transferred from the auxiliary electrode 502 to the positive electrode 208 and / or negative electrode 209 of the secondary battery 100.

[0132] In yet another embodiment, the positive electrode 208 can be replenished with carrier ions by simultaneously transferring carrier ions from the auxiliary electrode 502 to the positive electrode 208 of the secondary battery 100 and transferring carrier ions from the positive electrode 208 of the secondary battery 100 to the negative electrode 209 of the secondary battery 100. Referring to FIG. 6, a voltage is applied across the electrical terminals 124, 125 of the secondary battery 100 to drive carrier ions from the positive electrode 208 to the negative electrode 209 of the secondary battery 100. While the carrier ions are transferring from the positive electrode 208 to the negative electrode 209, a voltage is applied across the conductive tab 508-1 of the auxiliary electrode 502 and the positive electrode 208 of the secondary battery 100 to drive carrier ions from the auxiliary electrode 502 to the positive electrode 208 of the secondary battery 100. This causes carrier ions to transfer from the auxiliary electrode 502 to the positive electrode 208 of the secondary battery 100 at the same time as carrier ions transfer from the positive electrode 208 to the negative electrode 209 of the secondary battery 100. That is, a voltage sufficient to drive carrier ions from the positive electrode 208 to the negative electrode 209 of the secondary battery 100 is maintained across the positive electrode 208 and the negative electrode 209 of the secondary battery 100, and at the same time, a voltage sufficient to drive carrier ions from the auxiliary electrode 502 to the positive electrode 208 is maintained across the conductive tab 508-1 of the auxiliary electrode 502 and the positive electrode 208 of the secondary battery 100. In another embodiment, the initiation of carrier ion transfer from the auxiliary electrode 502 to the positive electrode 208 of the secondary battery 100 may begin simultaneously with the initiation of carrier ion transfer from the positive electrode 208 to the negative electrode 209 of the secondary battery 100. In one embodiment, the rate of carrier ion migration from the positive electrode 208 to the negative electrode 209 of the secondary battery 100 is equal to or greater than the rate of carrier ion migration from the auxiliary electrode 502 to the positive electrode 208 of the secondary battery 100, so that a good overall rate of carrier ion migration from the auxiliary electrode 502 to the negative electrode 209 of the secondary battery 100 via the positive electrode 208 can be maintained. That is, the relative rates of migration between the positive electrode 208 and the negative electrode 209, and between the auxiliary electrode 502 and the positive electrode 208 of the secondary battery 100 can be maintained so as not to exceed the overall capacity of the positive electrode 208 for additional carrier ions.This allows the positive electrode 208 to be maintained in a state capable of accepting new carrier ions from the auxiliary electrode 502, and allows the carrier ions to subsequently move to the negative electrode 209 of the secondary battery 100.

[0133] In one embodiment, without being limited by any particular theory, carrier ions are transferred from the auxiliary electrode 502 to the positive electrode 208 of the secondary battery 100 as part of replenishing the negative electrode 209 of the secondary battery 100 (as opposed to transferring directly from the auxiliary electrode 502 to the negative electrode 209 of the secondary battery) because the positive electrode 208 may be able to receive carrier ions more uniformly across its surface, thus allowing the carrier ions to participate more uniformly in their transfer between the positive electrode 208 and the negative electrode 209 of the secondary battery 100.

[0134] After the buffering process is performed on the secondary battery 100 using the buffering system 500, the auxiliary pole 502 can be removed from the buffering system 500 to improve the energy density of the secondary battery 100 in its final form. For example, after the buffering process, the carrier ion supply layer 706 (see FIG. 7) may be removed from the conductive layer 704 that has been electrochemically transferred to the secondary battery 100. Thus, the auxiliary pole 502 may not be needed at this point. To remove the auxiliary pole 502 from the enclosure 504 after the buffering process is performed, the enclosure layers 510, 511 of the enclosure may be cut along the cut lines 1702 illustrated as solid lines in FIG. 17, allowing the enclosure layers 510, 511 to be peeled away adjacent to the auxiliary pole 502. The auxiliary pole 502 is removed from the enclosure 504 of the buffering system 500, and the secondary battery 100 is left in the pouch 514 (see FIG. 12). The enclosure layers 510, 511 can then be resealed along a final sealing line 1704, illustrated as a dashed line, to form the enclosure 504 in its final form prior to use of the secondary battery 100. This resealing may be performed using any of the processes previously described for sealing the first enclosure layer 510 and the second enclosure layer 511 together.

[0135] FIG 18 is a flowchart of a method 1800 of pre-lithiating a secondary battery with carrier ions using an auxiliary electrode of an exemplary embodiment, and FIGS. 19-21 are flowcharts depicting further details of method 1800. Although method 1800 is described with respect to secondary battery 100, buffer system 500, and auxiliary electrode 502 of FIGS. 1-17, method 1800 may be applied to other systems not shown. The steps of method 1800 are not all inclusive, and method 1800 may include other steps not shown. Additionally, the steps of method 1800 may be performed in an alternate order.

[0136] In this embodiment, the secondary battery 100 (see FIG. 1 ) has opposing major surfaces 126, 127 and electrical terminals 124, 125. The electrical terminals 124, 125 are coupled to one of the positive electrode 208 of the secondary battery 100 (e.g., the collection of cathode structures 206 in the secondary battery 100 as depicted in FIG. 2 ) and the negative electrode 209 of the secondary battery 100 (e.g., the collection of anode structures 207 in the secondary battery 100 as depicted in FIG. 2 ). Between the negative electrode 209 and the positive electrode 208, the secondary battery 100 includes an electrolyte-permeated microporous separator layer 108 (see FIG. 2 ) that is in ionic contact with the negative electrode 209 and the positive electrode 208. The negative electrode 209 includes a positive electrode active material 104, such as silicon or an alloy thereof, that has a coulombic capacity for carrier ions. The positive electrode 208 includes a negative electrode active material 106 that has a coulombic capacity of carrier ions, and the coulombic capacity of the negative electrode 209 exceeds the coulombic capacity of the positive electrode 208 .

[0137] The auxiliary electrode 502 (see FIG. 6) is placed in contact with the main surfaces 126, 127 of the secondary battery 100 to form an auxiliary subassembly 516, and the auxiliary electrode 502 includes a conductive layer 704, a carrier ion supply layer 706 disposed on the conductive layer 704 adjacent to the main surfaces 126, 127 of the secondary battery 100, a separator 702 disposed between the carrier ion supply layer 706 and the main surfaces 126, 127 of the secondary battery, and a conductive tab 508 coupled to the conductive layer 704 (see step 1802 of FIG. 18 and FIGS. 12 to 15).

[0138] The auxiliary subassembly 516 is installed within the enclosure 504, with the electrical terminals 124, 125 of the secondary battery 100 and the conductive tab 508 of the auxiliary pole 502 electrically extending from the outer periphery 506 of the enclosure 504 (see step 1804 and FIG. 16).

[0139] Carrier ions are transferred from the positive electrode 208 of the secondary battery 100 to the negative electrode 209 of the secondary battery 100 by applying an electrical potential voltage across the electrical terminals 124, 125, at least partially charging the secondary battery 100 (see step 1806). Charging may be interrupted when the positive electrode 208 of the secondary battery 100 reaches its end-of-charge design voltage. During the initial charging cycle, an SEI may form on the internal structural surface of the negative electrode 209 of the secondary battery 100.

[0140] To compensate for the loss of carrier ions to the SEI and to further provide additional carrier ions to mitigate long-term secondary reactions during cycling in which carrier ions are lost through side reactions, carrier ions are transferred from the carrier ion supply layer 706 of the auxiliary electrode 502 to the positive electrode 208 and / or negative electrode 209 of the secondary battery 100 by applying a potential voltage across the conductive tab 508 of the auxiliary electrode 502 and one or more of the electrical terminals 124, 125 of the secondary battery 100 (see step 1808 of FIG. 16). Generally, this carrier ion buffering process transfers carrier ions from the carrier ion supply layer 706 of the auxiliary electrode 502 to each of the first major surface 126 of the secondary battery 100 and the second major surface 127 of the secondary battery 100 (see FIG. 15). Generally, transferring carrier ions into the secondary battery 100 from both of the major surfaces 126, 127 of the secondary battery 100, as depicted in FIG. 15, provides the technical advantage that more carrier ions are loaded into the negative and / or positive electrodes of the secondary battery 100, thereby distributing the forces generated by the expansion of the positive and / or negative electrodes more evenly across the casing 116 of the secondary battery 100.

[0141] In one embodiment, the amount of carrier ions transferred from the auxiliary electrode 502 to the secondary battery 100 is about 50% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100. In other embodiments, the amount of carrier ions transferred from the auxiliary electrode 502 to the secondary battery 100 is about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, or about 100% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100. In some embodiments, the amount of carrier ions transferred from the auxiliary electrode 502 to the secondary battery 100 is within a range of values ​​from about 1% to about 100% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100. In one particular embodiment, the negative electrode 209 of the secondary battery 100 has approximately 170% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100 stored as carrier ions when the secondary battery 100 is charged, and approximately 70% of the reversible coulombic capacity of the positive electrode 208 of the secondary battery 100 stored as carrier ions when the secondary battery 100 is discharged. The excess carrier ions in the negative electrode 209 of the secondary battery 100 provided during the buffering process provides the technical advantage of mitigating the loss of carrier ions in the secondary battery 100 due to the SEI upon initial formation. Furthermore, the excess carrier ions in the negative electrode 209 of the secondary battery 100 provided during the buffering process provides the technical advantage of mitigating the loss of carrier ions in the secondary battery 100 due to side reactions that deplete carrier ions in the secondary battery 100 when the secondary battery 100 is cycled during use, which reduces the capacity loss of the secondary battery 100 over time.

[0142] In some embodiments, the transfer of carrier ions from the auxiliary electrode 502 to the secondary battery 100 may occur simultaneously with the initial formation of the secondary battery 100 (e.g., during a first charge of the secondary battery 100) and / or during a subsequent charge of the secondary battery 100 after the initial formation. In these embodiments, the carrier ions are transferred from the positive electrode 208 of the secondary battery 100 to the negative electrode 209 of the secondary battery 100. Simultaneously or based on a time delay or pattern, the carrier ions are transferred from the auxiliary electrode 502 to the positive electrode 208 and / or negative electrode 209 of the secondary battery 100.

[0143] The carrier ions are transferred again from the positive electrode 208 of the secondary battery 100 to the negative electrode 209 of the secondary battery 100 by applying a potential voltage across the electrical terminals 124, 125 of the secondary battery 100, charging the secondary battery 100 until the negative electrode 209 exceeds 100% of the coulombic capacity of the positive electrode 208 stored as carrier ions (see step 1810).

[0144] In yet another embodiment, the positive electrode 208 can be replenished with carrier ions by simultaneously transferring carrier ions from the auxiliary electrode 502 to the positive electrode 208 of the secondary battery 100 and transferring carrier ions from the positive electrode 208 of the secondary battery 100 to the negative electrode 209 of the secondary battery 100. Referring to FIG. 6, a voltage is applied across the electrical terminals 124, 125 of the secondary battery 100 to drive carrier ions from the positive electrode 208 to the negative electrode 209 of the secondary battery 100. While the carrier ions are transferring from the positive electrode 208 to the negative electrode 209, a voltage is applied across the conductive tab 508-1 of the auxiliary electrode 502 and the positive electrode 208 of the secondary battery 100 to drive carrier ions from the auxiliary electrode 502 to the positive electrode 208 of the secondary battery 100. This causes carrier ions to transfer from the auxiliary electrode 502 to the positive electrode 208 of the secondary battery 100 at the same time as carrier ions transfer from the positive electrode 208 to the negative electrode 209 of the secondary battery 100. That is, a voltage sufficient to drive carrier ions from the positive electrode 208 to the negative electrode 209 of the secondary battery 100 is maintained across the positive electrode 208 and the negative electrode 209 of the secondary battery 100, and at the same time, a voltage sufficient to drive carrier ions from the auxiliary electrode 502 to the positive electrode 208 is maintained across the conductive tab 508-1 of the auxiliary electrode 502 and the positive electrode 208 of the secondary battery 100. In another embodiment, the initiation of carrier ion transfer from the auxiliary electrode 502 to the positive electrode 208 of the secondary battery 100 may begin simultaneously with the initiation of carrier ion transfer from the positive electrode 208 to the negative electrode 209 of the secondary battery 100. In one embodiment, the rate of carrier ion migration from the positive electrode 208 to the negative electrode 209 of the secondary battery 100 is equal to or greater than the rate of carrier ion migration from the auxiliary electrode 502 to the positive electrode 208 of the secondary battery 100, so that a good overall rate of carrier ion migration from the auxiliary electrode 502 to the negative electrode 209 of the secondary battery 100 via the positive electrode 208 can be maintained. That is, the relative rates of migration between the positive electrode 208 and the negative electrode 209, and between the auxiliary electrode 502 and the positive electrode 208 of the secondary battery 100 can be maintained so as not to exceed the overall capacity of the positive electrode 208 for additional carrier ions.This allows the positive electrode 208 to be maintained in a state capable of accepting new carrier ions from the auxiliary electrode 502, and allows the carrier ions to subsequently move to the negative electrode 209 of the secondary battery 100.

[0145] In one embodiment, without being limited by any particular theory, carrier ions are transferred from the auxiliary electrode 502 to the positive electrode 208 of the secondary battery 100 as part of replenishing the negative electrode 209 of the secondary battery 100 (as opposed to transferring directly from the auxiliary electrode 502 to the negative electrode 209 of the secondary battery) because the positive electrode 208 may be able to receive carrier ions more uniformly across its surface, thus allowing the carrier ions to participate more uniformly in their transfer between the positive electrode 208 and the negative electrode 209 of the secondary battery 100.

[0146] In some embodiments of method 1800, enclosure 504 is opened (see step 1902 of FIG. 19 ) and auxiliary pole 502 is removed from enclosure 504 (see step 1904). In response to removing auxiliary pole 502 from enclosure 504, the enclosure is resealed to its final form to enclose secondary battery 100 for use (see step 1906).

[0147] As previously described with respect to step 1804 detailed above, one particular embodiment installs the auxiliary subassembly 516 within the enclosure 504, but includes installing the auxiliary subassembly 516 on the first enclosure layer 510 (see step 2002 of FIG. 20). A second enclosure layer 511 is installed on the first enclosure layer 510 (see step 2004), and the first enclosure layer 510 and the second enclosure layer 511 are sealed together along the sealing line 1602 to form the enclosure 504 (see step 2006).

[0148] The enclosure layers 510, 511 may be sealed along a sealing line 1602 (see FIG. 16 ) by welding, heat sealing, adhesives, combinations thereof, and the like. In another embodiment, the enclosure layers 510, 511 may be sealed along three sides of the sealing line 1602 to form a pocket therein. In this embodiment, the secondary battery 100 may be placed in the pocket, after which the final edge of the sealing line 1602 is sealed. In one embodiment, the sealing line 1602 is sealed using a hot press, which applies a controlled temperature and pressure to the sealing line 1602 to bond or fuse the enclosure layers 510, 511 together along the sealing line 1602. In another embodiment, a vacuum is applied to the secondary battery 100 during the sealing process to evacuate any excess volume occupied by air or other gases. The time that the sealing line 1602 undergoes the hot press may be controlled and depends on the material selected for the enclosure layers 510, 511. When sealed over the secondary battery 100, the sealed enclosure layers 510, 511 form the cushioning system 500. When sealed, the cushioning system 500 is liquid-tight and / or air-tight, depending on the desired application. The electrical terminals 124, 125 and the conductive tabs 508 of the secondary battery 100 remain exposed and are not covered by the enclosure layers 510, 511.

[0149] In embodiments in which the first enclosure layer 510 includes a pouch 514, placing the auxiliary subassembly 516 in the enclosure 504 includes first disposing the auxiliary subassembly 516 in the pouch 514 (see step 2102 of FIG. 21 ). In some embodiments, electrolyte is added to the pouch 514 (e.g., either before or after placing the auxiliary subassembly 516 in the pouch 514), and then the enclosure 504 is formed by sealing the first enclosure layer 510 and the second enclosure layer 511 together along the seal line 1602.

[0150] The formation process performed on the secondary batteries 100 discussed above may be performed using any suitable system or systems for performing the formation process. In some embodiments, the formation process is performed by a distributed formation system, with each secondary battery 100 connected to a separate formation cluster that performs the formation process for the secondary battery 100 to which it is connected.

[0151] 22 is a block diagram of a cell formation system 2200 for an exemplary lithium-containing secondary battery, such as secondary battery 100. The cell formation system includes a population of formation clusters 2202 and a central controller 2204. Each formation cluster 2202 is connected to a secondary battery 100 and performs a formation process on the connected secondary battery 100.

[0152] The forming clusters 2202 are communicatively coupled to the central controller 2204 by a network 2206. The network 2206 may be any type of wired or wireless network suitable for communication between the forming clusters 2202 and the central controller 2204. For example, the network 2206 may be an Inter-Integrated Circuit (I2C) network, a Controller Area Network (CAN), a Local Area Network (LAN), a Wide Area Network (WAN), etc. Although shown connected to the same network 2206 in FIG. 22, the forming clusters 2202 and the central controller 2204 may be connected to different networks or a combination of the same and different networks. For example, some of the forming clusters 2202 may be connected to a first LAN and some of the forming clusters may be connected to a second LAN, and the first and second LANs may be connected to the central controller 2204 through a WAN that is connected to both the first and second LANs.

[0153] Each forming cluster 2202 is connected to a power source 2208, such as a power grid, a generator, a solar power system, a battery, etc. The forming clusters 2202 use power from the power source 2208 to power the forming clusters 2202 and perform the forming process. Although illustrated in FIG. 22 as being connected to the same power source 2208, the forming clusters 2202 in the cell forming system 2200 may be connected to different power sources 2208.

[0154] The group of forming clusters 2202 are supported by a housing 2210. The housing 2210 can be an enclosure such as a cabinet, or an open support such as a rack. For simplicity, two forming clusters 2202 are shown in one housing 2210 and a single forming cluster 2202 is shown in another housing 2210, but in practice, each housing 2210 typically supports a larger number of forming clusters 2202, such as 10, 25, 50, 100, 250, or 1000 forming clusters 2202. Notably, the central controller 2204 is separate from (and may be located remotely from) the housings 2210 and their forming clusters 2202. Furthermore, the housings 2210 may be located in different locations from each other, so long as they are located anywhere with access to a power source 2208 and a network 2206. Furthermore, each housing 2210 can support a different number of forming clusters 2202.

[0155] 23 is a block diagram of an example formation cluster 2202. The formation cluster 2202 includes a battery connector 2300, a charging module 2302, a pre-lithiation module 2304 (sometimes referred to as a buffer module), a discharging module 2306, a communication interface 2308, a formation cluster controller 2310, a power connection 2312, a power supply unit (PSU) 2313, and a sensor 2314.

[0156] The battery connector 2300 connects the formed cluster 2202 to the secondary battery 100. The battery connector 2300 can be any connector suitable for connecting to the secondary battery 100, including a connector configured to mate with a similar connector on the battery 100, a clamp connector (such as an alligator clip), wires soldered or welded to the battery 100 and the formed cluster 2202, etc. The battery connector 2300 is configured to connect to the positive and negative poles of the secondary battery 100. In some embodiments, the battery connector 2300 also electrically connects the formed cluster 2202 to the auxiliary pole 502. In other embodiments, the formed cluster 2202 includes a separate connector, referred to as a pre-lithiated connector, that electrically connects the formed cluster 2202 to the auxiliary pole 502. In some embodiments, the forming cluster 2202 includes two or more battery connectors 2300, each battery connector 2300 connected to a separate one of the modules of the forming cluster 2202 (e.g., a charging module 2302, a pre-lithiation module 2304, and a discharging module 2306).

[0157] The charging module 2302 is connected to the battery connector 2300 and configured to charge the secondary battery 100 connected to the battery connector 2300. The pre-lithiation module 2304 is connected to the battery connector 2300 and configured to diffuse lithium carrier ions to the electrode active material layers (e.g., the cathode active material layer 106 and / or the anode active material layer 104) of the secondary battery 100. The discharging module 2306 is connected to the battery connector 2300 and configured to discharge the secondary battery 100.

[0158] The communication interface 2308 connects the forming clusters 2202 to the central controller 2204. The communication interface 2308 may be any wired or wireless communication interface that allows the controllers 2310 to communicate with the central controller 2204 directly or over a network. The wireless communication interface 2308 may include a radio frequency (RF) transceiver, a Bluetooth adapter, a Wi-Fi transceiver, a ZigBee transceiver, an infrared (IR) transceiver, and / or any other device and communication protocol connection for wireless communication. (Bluetooth is a registered trademark of the Bluetooth Special Interest Group, Kirkland, Washington, and ZigBee is a registered trademark of the ZigBee Alliance, San Ramon, California.) The wired communication interface 2308 may use any suitable wired communication protocol for direct communication, including but not limited to USB, RS232, I2C, SPI, analog, and proprietary I / O protocols. In some embodiments, the wired communication interface 2308 includes a wired network adapter that enables the controller 2310 to be coupled to a network, such as the Internet, a local area network (LAN), a wide area network (WAN), a mesh network, and / or any other network, for communicating with remote devices and systems over the network.

[0159] The formation cluster controller 2310 controls the operation of the formation cluster 2202 to operate as described herein. The formation cluster controller 2310 includes a processor 2316 and a memory 2318. The processor 2316 is any programmable system including a microcontroller, a microcomputer, a microprocessor, a reduced instruction set circuit (RISC), an application specific integrated circuit (ASIC), a programmable logic circuit (PLC), and any other circuit or processor capable of performing the functions described herein. The memory 2318 stores computer readable instructions executable by the processor 2316 for control of the formation cluster 2202 as described herein. The memory 2318 can be any suitable type of memory including, but not limited to, a random access memory (RAM), such as a dynamic RAM (DRAM) or a static RAM (SRAM), a read only memory (ROM), an erasable programmable read only memory (EPROM), an electrically erasable programmable read only memory (EEPROM), and a non-volatile RAM (NVRAM). In some embodiments, the processor 2316 and the memory 2318 are both embodied within a microcontroller, while in other embodiments, the processor 2316 and the memory 2318 are separate components.

[0160] In an exemplary embodiment, the formation cluster controller 2310 is programmed (by instructions stored in memory 2318) to directly control each of the modules 2302, 2304, and 2306. That is, the formation cluster controller 2310 is programmed to control the charging module 2302 to charge the secondary battery 100, the pre-lithiation module 2304 to pre-lithiate (also referred to as buffering) the secondary battery 100, and the discharging module 2306 to discharge the secondary battery 100. The formation cluster controller 2310 is also programmed to control the entire formation process, including when to use each of the modules 2302, 2304, and 2306.

[0161] In other embodiments, one or more of the modules 2302, 2304, and 2306 include their own module controllers (having a processor and memory). In such embodiments, the formation cluster controller 2310 controls the entire formation process, but the module controllers control the specific tasks of those modules. For example, the formation cluster controller 2310 may instruct the charging module 2302 to charge the secondary battery 100, and then the module controller in the charging module 2302 controls the charging module 2302 to charge the secondary battery 100 according to instructions stored in the memory of the charging module's module controller.

[0162] In further embodiments, the forming cluster 2202 does not include a forming cluster controller 2310. Rather, each of the modules 2302, 2304, and 2306 includes its own module controller. In such embodiments, the central controller 2204 controls the entire forming process and sends instructions to the module controllers through the communications interface 2308. In such embodiments, the multiple module controllers in the forming cluster 2202 can be considered a distributed forming cluster controller 2310.

[0163] Various levels of interaction and control may be performed by the central controller 2204 and the forming cluster controller 2310 in different embodiments. For example, in some embodiments, the central controller 2204 simply sends instructions to the forming cluster 2202 to initiate the forming process. Then, in response to the instructions, the forming cluster controller 2310 controls the modules 2302, 2304, and 2306 to perform the forming process. Alternatively, in response to the instructions, the forming cluster controller 2310 may instruct the modules 2302, 2304, and 2306 to perform their respective functions at the appropriate times. In other embodiments, the central controller 2204 sends instructions to the forming cluster 2202 to perform individual parts of the forming process (e.g., "charge the battery here"), and the forming cluster controller 2310 or the module controllers perform the tasks instructed by the central controller 2204. In some embodiments, the central controller 2204 may send instructions to the forming cluster 2202 on how to perform one or more of the forming tasks, including sending a control algorithm. In some embodiments, the forming cluster controller 2310 or module controller may store instructions for multiple methods of performing the same task (e.g., fast charging, slow charging, charging with rest periods, etc.), and the central controller's instructions may instruct the forming cluster 2202 which method to use.

[0164] In some embodiments, the central controller 2204 can program or update the programming of the formation cluster controllers 2310 or the module controllers. For example, the central controller 2204 can send a control algorithm to the formation cluster 2202, and the formation cluster controller 2310 and / or the module controllers can store the control algorithm in their respective memories. In other embodiments, the central controller 2204 can send modifications to a control algorithm already stored in the formation cluster 2202, such as changing variables, changing timing, etc. The formation cluster controller 2310 or the controller module then stores the modifications in memory for use in the formation process.

[0165] The formation cluster controller 2310, in some embodiments, also transmits information back to the central controller 2204. The information sent to the central controller 2204 may include confirmation that the command was received, confirmation that the commanded process has begun, the status of the operation being performed, data collected from the sensors 2314, or any other suitable information.

[0166] The power connection 2312 connects the forming cluster 2202 to the power source 2208. The power connection 2312 can be any connector suitable for connecting to the power source 2208, including a plug configured to insert into a mating socket of the power source 2208, a wire soldered or welded to the power source 2208, a clamp connector for clamping to a terminal or wire of the power source 2208, etc. The PSU 2313 converts and / or distributes power from the power source 2208 to the remainder of the forming cluster 2202 for use in the forming process. The PSU 2313 can be an AC / DC power converter, a DC / DC power converter, an inverter, or any other unit suitable for converting power and / or distributing power to the forming cluster 2202. Some embodiments do not include a PSU and utilize power directly from the power source 2208.

[0167] The sensor 2314 is any sensor capable of monitoring a variable important to the formation process. For example, the sensor 2314 may be a voltage sensor for monitoring the voltage of the secondary battery 100, an ambient temperature sensor for monitoring the temperature surrounding the formation cluster 2202, a temperature sensor for monitoring the temperature of the battery 100 or a component of the formation cluster 2202, a current sensor for monitoring the current flowing into, from, or through the battery 100, etc. Some embodiments include more than one sensor 2314, including a combination of the aforementioned sensors. Furthermore, some sensors 2314 may perform more than one of the above-mentioned monitoring tasks.

[0168] The modular and distributed nature of the cell formation system 2200 allows the system to be easily expanded or contracted as desired. Unlike conventional centralized systems that are configured to form a set number of batteries at a time, the system 2200 can be expanded to any number of batteries by simply adding more forming clusters 2202 (including increasing the number of batteries by as little as one additional battery). In conventional centralized systems, increasing the number of batteries formed requires the acquisition of additional systems and an increase in a set number of batteries (determined by the size and configuration of the centralized system obtained). Furthermore, centralized systems typically require running significant additional wiring to each additional battery to provide controlled power and communication to the additional batteries. In contrast, the cell formation system 2200 only requires connecting the additional forming clusters 2202 to a power source and an existing communication network. The forming clusters 2202 in the system 2200 do not all need to be the same, as long as the central controller 2204 knows the configuration of each forming cluster 2202. Furthermore, the forming clusters 2202 in the system 2200 can be used to form different batteries at different times or simultaneously, so long as the central controller 2204 or forming cluster controller 2310 knows which secondary batteries 100 are connected to the forming clusters 2202.

[0169] 24 is a block diagram of an exemplary pre-lithiation module 2304 for use in the formation cluster 2202. As described above, the pre-lithiation module 2304 is configured to diffuse lithium into an electrode active material layer (e.g., the cathode active material layer 106 and / or the anode active material layer 104) of the secondary battery 100. The pre-lithiation module 2304 includes a switched capacitor circuit 2400, a pre-lithiation module controller 2402, a battery connector 2404, a pre-lithiation connector 2406, and a communication interface 2408.

[0170] The switched capacitor circuit 2400 is a switched resistor-capacitor network. The switched capacitor circuit 2400 is described in more detail below with reference to FIG. 25. Generally, in a first stage, a current is passed through the circuit 2400 to charge the capacitor network, and then in a second stage, the energy stored in the capacitor network is discharged through a discharge resistor and released as heat. In the pre-lithiation module 2304, the current passed to charge the capacitor network is a current between the auxiliary electrode 502 and one pole of the secondary battery 100 to diffuse lithium from the auxiliary electrode 502 to the electrode active material layer of the secondary battery 100.

[0171] The pre-lithiation module controller 2402 controls the operation of the pre-lithiation module 2304 to pre-lithiate the secondary battery 100 by selectively passing a current through the auxiliary electrode 502 to diffuse lithium into the electrode active material layer of the secondary battery 100. The pre-lithiation module controller 2402 includes a processor 2410 and a memory 2412. The memory 2412 stores instructions that, when executed by the processor 2410, cause the processor 2410 to perform pre-lithiation as described herein. The processor 2410 is any programmable system, including a microcontroller, microcomputer, microprocessor, reduced instruction set circuit (RISC), application specific integrated circuit (ASIC), programmable logic circuit (PLC), and any other circuit or processor capable of performing the functions described herein. The memory 2412 may be any suitable type of memory, including, but not limited to, random access memory (RAM), such as dynamic RAM (DRAM) or static RAM (SRAM), read only memory (ROM), erasable programmable read only memory (EPROM), electrically erasable programmable read only memory (EEPROM), and non-volatile RAM (NVRAM). In some embodiments, the processor 2410 and memory 2412 are both embodied within a microcontroller, while in other embodiments the processor and memory are separate components.

[0172] The battery connector 2404 connects the pre-lithiation module 2304 to the secondary battery 100. The battery connector 2404 may be the battery connector 2300 or may be a separate battery connector connected only to the pre-lithiation module 2304. The battery connector 2404 may be any connector suitable for connection to the secondary battery 100, including a connector configured to mate with a similar connector on the battery 100, a clamp connector (such as an alligator clip), wires soldered or welded to the battery 100 and the pre-lithiation module 2304, etc. The battery connector 2404 is configured to connect to the positive and negative poles of the secondary battery 100.

[0173] The pre-lithiated connector 2406 connects the pre-lithiated module 2304 to the auxiliary pole 502 of the secondary battery 100. The pre-lithiated connector 2404 can be any connector suitable for connection to the secondary battery 100, including a connector configured to mate with a similar connector on the battery 100, a clamp connector (such as an alligator clip), wires soldered or welded to the battery 100 and the pre-lithiated module 2304, etc. In some embodiments, the pre-lithiated connector 2406 is part of the battery connector 2300.

[0174] The communication interface 2408 connects the pre-lithiation module 2304 to the central controller 2204. The communication interface 2408 may be the communication interface 2308 or may be a separate communication interface. The communication interface 2408 may allow the pre-lithiation module 2304 to communicate directly with the central controller 2204 or may allow the pre-lithiation module 2304 to communicate indirectly with the central controller 2204, for example, via the formation cluster controller 2310. The communication interface 2408 may be any wired or wireless communication interface that allows the controller 2402 to communicate with the communication central controller 2204 directly or over a network. The wireless communication interface 2408 may include a radio frequency (RF) transceiver, a Bluetooth adapter, a Wi-Fi transceiver, a ZigBee transceiver, an infrared (IR) transceiver, and / or any other device and communication protocol connection for wireless communication. (Bluetooth is a registered trademark of the Bluetooth Special Interest Group, Kirkland, Washington, and ZigBee is a registered trademark of the ZigBee Alliance, San Ramon, California.) The wired communications interface 2408 can use any suitable wired communications protocol for direct communications, including, but not limited to, USB, RS232, I2C, SPI, analog, and proprietary I / O protocols. In some embodiments, the wired communications interface 2308 includes a wired network adapter that allows the controller 2402 to be coupled to a network, such as the Internet, a local area network (LAN), a wide area network (WAN), a mesh network, and / or any other network, for communicating with remote devices and systems over the network.

[0175] 25 is a simplified circuit diagram of an exemplary embodiment of a switched capacitor circuit 2400 connected to a secondary battery 100. The switched capacitor circuit 2400 includes a microcontroller 2500, a storage capacitor 2502, a discharge resistor 2504, a first switch 2506, and a second switch 2508.

[0176] Microcontroller 2500 controls switched capacitor circuit 2400 according to a control algorithm stored in its memory. In an exemplary embodiment, microcontroller 2500 is also pre-lithiation module controller 2402. In other embodiments, pre-lithiation module controller 2402 is separate from microcontroller 2500. In an exemplary embodiment, the microcontroller is a PIC 16F15323 microcontroller from Microchip Technology Inc. of Chandler, Arizona, USA. In other embodiments, any other suitable microcontroller may be used. In this embodiment, microcontroller 502 is powered by power supply 2208 via PSU 2313.

[0177] The microcontroller 2500 controls the pre-lithiation of the secondary battery 100 by selectively conducting current through the auxiliary pole 502 by controlling the first switch 2506 and the second switch 2508. The first switch 2506 is an N-channel enhancement mode metal oxide semiconductor field effect transistor (MOSFET), and the second switch 2508 is a P-channel enhancement mode MOSFET. Other embodiments may use any other suitable switches. By closing the first switch 2506 and opening the second switch 2504, the microcontroller 2500 forms a first current path from the negative electrode bus bar 112 of the secondary battery 100 through the first switch 2506 to the auxiliary pole 502. The first current path includes a storage capacitor 2502. When a current flows through the first current path, lithium diffuses from the auxiliary pole 502 to the electrode active material layer of the secondary batter 100, and energy is stored in the storage capacitor 2502. The microcontroller 2500 then closes the second switch 2508 and opens the first switch 2506 to establish a second current path. The second current path includes a storage capacitor 2502, a discharge resistor 2504, and a second switch 2508. As current flows through the second current path, the energy stored in the capacitor 2502 is discharged through the discharge resistor 2504 and released as heat.

[0178] In this embodiment, lithium migrates from the auxiliary electrode 502 to the electrode active material layer of the positive electrode of the secondary battery 100. In other embodiments, the diffusion is to the electrode active material layer of the negative electrode of the secondary battery 100 by connecting the switched capacitor circuit 2400 such that the first current loop includes the anode bus bar 110 instead of the cathode bus bar 112. In still other embodiments, the switched capacitor circuit 2400 may be replicated such that there are two first current loops, one including the anode bus bar 110 and the other including the cathode bus bar 112. Such an embodiment allows a single pre-lithiation module 2304 to migrate lithium from the auxiliary electrode 502 to the active material layers of the positive and negative electrodes of the secondary battery 100 without the need to stop the formation process to reconfigure the connections to the secondary battery 100 and the auxiliary electrode 502, and without the need to use two separate pre-lithiation modules 2304.

[0179] Pre-lithiation of the secondary battery 100 using the switched capacitor circuit 2400 generally draws charge from the secondary battery 100 at a time, small packets at a time, at a high rate. Thus, the average current is equal to the packet charge / discharge frequency multiplied by the packet size in coulombs, as shown by:

number

number

[0180] To control the switched capacitor circuit 2400, the microcontroller 2500 uses a pulse frequency modulation (PFM) control signal to the first switch 2506 and the second switch 2508. PFM is described by pulses with a fixed width (i.e., each pulse is on for a fixed length of time) with a variable time between the pulses. The time between the pulses is varied to provide different frequencies for charge transfer. The faster the packets move (i.e., the shorter and higher the frequency of the fixed width pulses), the higher the current conducted through the auxiliary pole 502. Conversely, the lower the frequency of the pulses (i.e., the longer the time between the pulses), the lower the current conducted through the auxiliary pole 502. The upper limit of the current conducted through the auxiliary pole 502 is determined by the settling time of the RC circuit element of the switched capacitor circuit 2400. Thus, by varying the frequency of the control pulses to the switches 2506 and 2508, the microcontroller 2500 can control the current flowing through the auxiliary pole 502. In another embodiment, the microcontroller 2500 uses pulse width modulated (PWM) control signals to the first switch 2506 and the second switch 2508. With PWM control, pulses occur at a fixed frequency, but the length of each pulse can be varied to control the amount of charge moved, thereby controlling the amount of current.

[0181] FIG. 26 is a graph of a series of PFM control pulses applied to switches 2506 and 2508 as a function of time. As can be seen, in a first portion 2600 of the series of pulses, fixed width pulses are applied at a higher frequency than in a second portion 2602 of the series of pulses. FIG. 27 is a graph of the resulting current through the auxiliary pole 502 in response to the control pulses shown in FIG. 26 as a function of time. The current increases in a sawtooth pattern during the first portion 2600 to a first maximum current 2604. When the frequency of the pulses is reduced in the second portion 2602, the current through the auxiliary pole 502 decreases to a second maximum current 2606 that is lower than the first maximum current 2604.

[0182] 28 is a circuit diagram of an example implementation of a switched-capacitor circuit 2400 connected to a secondary battery 100. Similar components share reference numbers with corresponding components in FIG. 25. In this embodiment, the microcontroller 2500 is powered by the secondary battery 100 rather than the PSU 2313. The microcontroller 2500 presents a small leakage on the secondary battery 100, generally in the range of 50 nA to 100 nA, in most situations except when it is active.

[0183] During the pre-lithiation process, the microcontroller 2500 detects the voltage V c and the voltage V at the auxiliary electrode 502 L Monitor the cathode voltage V c To measure V, pin RC3 of the microcontroller 2500 is driven low with respect to the positive terminal of the secondary battery 100, which is considered the reference point for this circuit. This creates a voltage divider, y is read out on pin RA0 of the microcontroller 2500. Then, the cathode voltage V c is calculated by the microcontroller 2500 as follows:

number

number

number

number

[0184] When measuring the voltage, the microcontroller 2500 may use filtering to increase the stability of the measurement. For example, the microcontroller 2500 may use decimation, non-linear IIR filtering, or some combination of such signal processing to improve measurement stability. Filtering can improve resolution and reduce noise before the data is consumed by the management functions of the microcontroller 2500. This provides a relatively clean decision-making regardless of any external factory noise that may otherwise affect the measurement. Because pre-lithiation is a relatively slow process (often requiring tens of hours), fairly significant signal processing can be used without much concern regarding time.

[0185] 29-31 are graphs of exemplary pre-lithiation profiles used by the microcontroller 2500 to perform pre-lithiation of the secondary battery 100. FIG. 29 is a graph showing the buffer current (i.e., the current through the auxiliary electrode 502) as a function of the voltage difference (in millivolts (mV)) between the negative electrode of the secondary battery 100 and the auxiliary electrode 502. FIG. 30 is a graph showing the period of the pulses as a function of the voltage difference (mV) between the negative electrode of the secondary battery 100 and the auxiliary electrode 502. FIG. 31 is a graph showing the number of pulses as a function of the voltage difference (mV) between the negative electrode of the secondary battery 100 and the auxiliary electrode 502. Of course, different profiles may be used for secondary batteries 100 with different capacities and / or upper charging voltage limits.

[0186] The pre-lithiation profiles shown in Figures 29-31 were used in conjunction with the implementation of the switched capacitor circuit 2400 shown in Figure 25 to pre-lithiate the secondary battery 100. The results of this process are shown in Figures 32 and 33. Figure 32 is a graph of the cathode-to-anode voltage 2900 and the cathode-to-auxiliary voltage 2902 as a function of time. Figure 33 is a graph of the buffer current as a function of time.

[0187] The embodiments of the present disclosure utilize an auxiliary electrode to transfer or buffer carrier ions to a secondary battery during or after the initial formation of the secondary battery. Transferring carrier ions to a secondary battery (also referred to as pre-lithiation or buffering) provides the technical advantage of mitigating carrier ion losses during formation, for example, by SEI, thereby improving the capacity of the secondary battery. Furthermore, transferring carrier ions to a secondary battery provides the negative electrode of the secondary battery with additional carrier ions in excess of the positive electrode coulombic capacity of the secondary battery, thereby providing a reservoir of additional carrier ions over the cycle life of the secondary battery, further mitigating carrier ion losses during cycling due to side reactions that remove carrier ions from availability during cycling. The result of the additional carrier ions in the negative electrode provides the further technical advantage of reducing the amount of capacity loss in the secondary battery from one discharge-charge cycle to the next, thereby improving the overall capacity of the secondary battery during cycle life.

[0188] The following embodiments are provided to illustrate various aspects of the present disclosure. The following embodiments are not intended to be limiting, and thus the present disclosure further supports other aspects and / or embodiments not specifically provided below.

[0189] Embodiment 1. A cell formation system for lithium-containing secondary batteries. Each lithium-containing secondary battery includes a population of bilayers, an electrode busbar, and a counter electrode busbar, each bilayer of the population of bilayers includes an electrode structure, a separator structure, and a counter electrode structure, the electrode structure of each member of the bilayer population includes an electrode current collector and an electrode active material layer, and the counter electrode structure of each member of the bilayer population includes a counter electrode current collector and a counter electrode active material layer. The cell formation system includes a population of formation clusters, each formation cluster of the population of formation clusters includes a connector configured to connect to a lithium-containing secondary battery, a charging module connected to the connector and configured to charge the lithium-containing secondary battery connected to the connector, a pre-lithiation module connected to the connector and configured to diffuse lithium into the electrode active material layer of the lithium-containing secondary battery connected to the connector, a discharging module connected to the connector and configured to discharge the lithium-containing secondary battery connected to the connector, and a communication interface for communicatively coupling the formation cluster to a central controller. The formation cluster is configured, in response to instructions received from the central controller, to charge a lithium-containing secondary battery connected to the connector using the charging module, to diffuse lithium into an electrode active material layer of the lithium-containing secondary battery using the pre-lithiation module after the lithium-containing secondary battery has been charged, and to discharge the lithium-containing secondary battery using the discharging module after lithium has been diffused into an electrode active material layer of the lithium-containing secondary battery using the pre-lithiation module.

[0190] Embodiment 2. A cell formation system as described in embodiment 1, wherein the central controller includes a processor, a memory, and a controller communication interface for communicatively coupling the central controller to a population of forming clusters, the central controller being programmed with instructions stored in the memory and executed by the processor to provide instructions to the population of forming clusters.

[0191] Embodiment 3. A cell formation system as described in any one of the preceding embodiments, wherein each formation cluster further includes a power connection configured for connection to a power source, the power connection being coupled to the charging module, the pre-lithiation module, and the discharge module.

[0192] Embodiment 4. The cell formation system of any one of the preceding embodiments, wherein each formation cluster further includes a formation cluster controller including a processor and a memory, the formation cluster controller being programmed with instructions stored in the memory and executed by the processor to control the charging module, the pre-lithiation module, and the discharging module in response to instructions received from the central controller.

[0193] Embodiment 5. A cell formation system as described in embodiment 4, wherein the formation cluster controller includes a microcontroller.

[0194] Embodiment 6. A cell formation system as described in embodiment 4 or 5, wherein each forming cluster further includes at least one sensor, and the forming cluster controller is programmed to receive a signal output by the at least one sensor and transmit the received signal output to the central controller using a communication interface.

[0195] Embodiment 7. A cell formation system as described in any one of the preceding embodiments, wherein the charging module, pre-lithiation module, and discharge module of each formation cluster each further include a module controller including a processor and a memory, each module controller being programmed with instructions stored in the memory and executed by the processor to control its associated one of the charging module, pre-lithiation module, and discharge module in response to instructions received from the central controller.

[0196] Embodiment 8. A cell formation system as described in embodiment 7, wherein the module controller includes a microcontroller.

[0197] Embodiment 9. A cell formation system as described in embodiment 7 or 8, wherein each forming cluster further includes at least one sensor, and at least one of the module controllers is programmed to receive a signal output by the at least one sensor and transmit the received signal output to the central controller using a communication interface.

[0198] Embodiment 10. A cell formation system as described in embodiment 6 or 9, wherein at least one sensor includes a temperature sensor.

[0199] Embodiment 11. A cell formation system as described in embodiment 6, 9, or 10, wherein at least one sensor includes a voltage sensor.

[0200] Embodiment 12. A cell formation system as described in embodiment 6, 9, 10, or 11, wherein at least one sensor includes a current sensor.

[0201] Embodiment 13. A cell formation system according to any one of the preceding embodiments, further comprising a housing supporting a population of formed clusters.

[0202] Embodiment 14. A cell formation system as described in any one of the preceding embodiments, further comprising a communication network connected to the communication interface of each forming cluster of the population of forming clusters.

[0203] Embodiment 15. A cell formation system described in any one of embodiments 1 to 13, wherein the communication interface of each forming cluster of the group of forming clusters includes a wireless communication interface.

[0204] Embodiment 16. The cell formation system according to any one of the preceding embodiments, further comprising a population of additional formation clusters, each additional formation cluster of the population of additional formation clusters comprising a connector configured for connection to a lithium-containing secondary battery, a charging module connected to the connector and configured to charge the lithium-containing secondary battery connected to the connector, a pre-lithiation module connected to the connector and configured to diffuse lithium into an electrode active material layer of the lithium-containing secondary battery connected to the connector, a discharging module connected to the connector and configured to discharge the lithium-containing secondary battery connected to the connector, and a communication interface for communicatively coupling the formation cluster to a central controller. The formation cluster is configured to charge the lithium-containing secondary battery connected to the connector using the charging module, diffuse lithium into the electrode active material layer of the lithium-containing secondary battery using the pre-lithiation module after the lithium-containing secondary battery is charged, and discharge the lithium-containing secondary battery using the discharging module after the lithium is diffused into the electrode active material layer of the lithium-containing secondary battery using the pre-lithiation module, in response to instructions received from the central controller.

[0205] Embodiment 17. A cell formation system as described in embodiment 16, further comprising an additional housing supporting a population of additional formed clusters.

[0206] Embodiment 18. A cell formation system according to any one of the preceding embodiments, wherein the lithium-containing secondary battery connected to the connector includes an auxiliary electrode containing lithium, and the forming cluster is configured to selectively conduct current through the auxiliary electrode using a pre-lithiation module to diffuse lithium into the electrode active material layer of the lithium-containing secondary battery.

[0207] Embodiment 19. The cell formation system of embodiment 18, wherein the auxiliary electrode includes a first separator layer including an ion-permeable material, a conductive layer including a conductive material, the conductive layer having a first surface in contact with the first separator layer and a second surface opposite the first surface, a population of carrier ion supply layers disposed on the second surface of the conductive layer, each carrier ion supply layer including a material that supplies lithium ions to an electrode active material layer of a lithium-containing secondary battery, and a second separator layer including an ion-permeable material and in contact with the carrier ion supply layers.

[0208] Embodiment 20. A cell formation system as described in embodiment 19, wherein the second surface of the conductive layer includes a first region disposed at a first end of the conductive layer, a second region disposed at a second end of the conductive layer opposite the first end, and a third region disposed between the first region and the second region, and one of the carrier ion supply layers is disposed in the first region and another one of the carrier ion supply layers is disposed in the second region.

[0209] Embodiment 21. The cell formation system of embodiment 20, wherein the second separator layer is in contact with a third region of the second surface of the conductive layer.

[0210] Embodiment 22. A cell formation system as described in embodiment 20 or embodiment 21, wherein the first region, the second region, and the third region are disposed along the length of the conductive layer.

[0211] Embodiment 23. A cell formation system described in any one of embodiments 19 to 22, wherein the first separator layer and the second separator layer are mechanically joined together around at least a portion of the periphery of the first separator layer and the second separator layer.

[0212] Embodiment 24. A cell formation system described in any one of embodiments 19 to 23, wherein the first separator layer and the second separator layer are formed from a continuous separator material, the first separator layer comprising a first portion of the continuous separator material, and the second separator layer comprising a second portion of the continuous separator material, the second portion being folded over the first portion so as to contact the surface of the carrier ion supply layer.

[0213] Embodiment 25. The cell formation system of embodiment 24, wherein the continuous separator material has a thickness in the range of about 0.01 millimeters to about 1 millimeter.

[0214] Embodiment 26. A cell formation system as described in embodiment 25, wherein the thickness of the continuous separator material is about 0.025 millimeters.

[0215] Embodiment 27. A cell formation system described in any one of embodiments 19 to 26, wherein the first separator layer and the second separator layer have a thickness within a range of values ​​from about 0.01 millimeters to about 1 millimeter.

[0216] Embodiment 28. A cell formation system described in any one of embodiments 19 to 27, wherein the thickness of the second separator layer is about 0.025 millimeters.

[0217] Embodiment 29. A cell formation system according to any one of embodiments 19 to 28, wherein the conductive layer comprises one of copper and aluminum, or an alloy of copper and aluminum.

[0218] Embodiment 30. A cell formation system according to any one of embodiments 19 to 29, wherein the conductive layer comprises copper.

[0219] Embodiment 31. A cell formation system described in any one of embodiments 19 to 30, wherein the conductive layer has a thickness within a range of values ​​from about 0.01 millimeters to about 1 millimeter.

[0220] Embodiment 32. A cell formation system according to any one of embodiments 19 to 31, wherein the conductive layer has a thickness of about 0.1 millimeters.

[0221] Embodiment 33. A cell formation system according to any one of embodiments 19 to 32, wherein the carrier ion supply layer has a thickness within a range of values ​​from about 0.05 millimeters to about 1 millimeter.

[0222] Embodiment 34. A cell formation system according to any one of embodiments 19 to 33, wherein the carrier ion supply layer has a thickness of about 0.15 millimeters.

[0223] Embodiment 35. The cell formation system according to any one of embodiments 19 to 34, wherein the carrier ion supply layer provides a source of lithium ions.

[0224] Embodiment 36. A cell formation system described in any one of embodiments 19 to 35, wherein the carrier ion supply layer is cold welded to the second surface of the conductive layer.

[0225] Embodiment 37. A cell formation system described in any one of embodiments 19 to 36, wherein the auxiliary electrode comprises a conductive material and includes a conductive tab bonded to the second surface of the conductive layer.

[0226] Embodiment 38. A cell formation system as described in embodiment 37, wherein the conductive tab includes a first end coupled to the conductive layer and a second end distal to the first end that protrudes away from the conductive layer.

[0227] Embodiment 39. A cell formation system as described in embodiment 37 or 38, wherein the conductive tab comprises one of nickel, copper, and aluminum, or an alloy of copper, nickel, and aluminum.

[0228] Embodiment 40. The cell formation system of embodiment 37 or 38, wherein the conductive tab comprises nickel.

[0229] Embodiment 41. A cell formation system according to any one of the preceding embodiments, wherein the electrode structure is one of a positive electrode and a negative electrode, and the counter electrode structure is the other of a positive electrode and a negative electrode, the positive electrode having a positive electrode coulombic capacity, and the negative electrode having a negative electrode coulombic capacity that exceeds the positive electrode coulombic capacity.

[0230] Embodiment 42. The cell formation system of embodiment 41, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 1.2:1.

[0231] Embodiment 43. The cell formation system of embodiment 41, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 1.3:1.

[0232] Embodiment 44. The cell formation system of embodiment 41, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 1.5:1.

[0233] Embodiment 45. The cell formation system of embodiment 41, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 2:1.

[0234] Embodiment 46. The cell formation system of embodiment 41, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 3:1.

[0235] Embodiment 47. The cell formation system of embodiment 41, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 4:1.

[0236] Embodiment 48. The cell formation system of embodiment 41, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 5:1.

[0237] Embodiment 49. A cell formation system described in any one of embodiments 18 to 40, wherein the electrode structure is one of a positive electrode and a negative electrode, and the counter electrode structure is the other of a positive electrode and a negative electrode, the positive electrode has a positive electrode coulombic capacity, and the negative electrode has a negative electrode coulombic capacity that exceeds the positive electrode coulombic capacity.

[0238] Embodiment 50. The cell formation system of embodiment 49, wherein the ratio of the coulombic capacity of the negative electrode to the coulombic capacity of the positive electrode is at least 1.2:1, at least 1.3:1, at least 1.5:1, at least 2:1, at least 3:1, at least 4:1, or at least 5:1.

[0239] Embodiment 51. A cell formation system as described in embodiment 49 or 50, wherein the ratio of the coulombic capacity of the auxiliary electrode to the coulombic capacity of the positive electrode is at least 2:1.

[0240] Embodiment 52. A cell formation system as described in embodiment 49 or 50, wherein the ratio of the coulombic capacity of the auxiliary electrode to the coulombic capacity of the positive electrode is at least 3:1.

[0241] Embodiment 53. A cell formation system as described in embodiment 49 or 50, wherein the ratio of the coulombic capacity of the auxiliary electrode to the coulombic capacity of the positive electrode is at least 4:1.

[0242] Embodiment 54. A cell formation system as described in embodiment 49 or 50, wherein the ratio of the coulombic capacity of the auxiliary electrode to the coulombic capacity of the positive electrode is at least 5:1.

[0243] Embodiment 55. The cell formation system according to any one of the preceding embodiments, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises anode active silicon or an alloy thereof.

[0244] Embodiment 56. The cell formation system of any one of the preceding embodiments, wherein the electrode active material layer or counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material comprising silicon and contains a void volume fraction to accommodate volumetric expansion and contraction as lithium ions are incorporated into or depart from the electrode active material layer or counter electrode active material layer during charge and discharge cycles of the lithium-containing secondary battery.

[0245] Embodiment 57. The cell formation system of embodiment 56, wherein the void volume fraction of the anode active material is at least 0.1.

[0246] Embodiment 58. The cell formation system of embodiment 56, wherein the void volume fraction of the anode active material is 0.8 or less.

[0247] Embodiment 59. The cell formation system of embodiment 56, wherein the void volume fraction of the anode active material is about 0.15 to about 0.75.

[0248] Embodiment 60. The cell formation system of embodiment 56, wherein the void volume fraction of the anode active material is about 0.2 to about 0.7.

[0249] Embodiment 61. The cell formation system of embodiment 56, wherein the void volume fraction of the anode active material is about 0.25 to about 0.6.

[0250] Embodiment 62. The cell formation system of embodiment 56, wherein the anode active material comprises a macroporous, microporous, or mesoporous material layer, or a combination thereof.

[0251] Embodiment 63. A cell formation system according to any one of the preceding embodiments, wherein the separator structure comprises a microporous separator permeated with an electrolyte between the electrode structure and the counter electrode structure.

[0252] Embodiment 64. The cell formation system of embodiment 63, wherein the separator or electrolyte comprises a polymer-based electrolyte selected from one or more of a PEO-based polymer electrolyte, a polymer-ceramic composite electrolyte, a polymer-ceramic composite electrolyte, and a polymer-ceramic composite electrolyte.

[0253] Embodiment 65. The separator or electrolyte is lithium lanthanum titanate (Li 0.34 La 0.56 TiO3), Al-doped lanthanum zirconate lithium (Li 6.24 La3Zr2Al 0.24 O 11.98), Ta-doped lithium lanthanum zirconate (Li 6.4 La3Zr 1.4 Ta 0.6 O 12 ), and lithium aluminum titanium phosphate (Li 1.4 Al 0.4 Ti 1.6 65. The cell formation system of embodiment 63 or 64, comprising an oxide-based electrolyte selected from one or more of: (PO4)3).

[0254] Embodiment 66. The separator or electrolyte is lithium tin sulfide (Li 10 SnP2S 12 ), lithium phosphorus sulfide (β-Li3PS4), and lithium sulfide chloride (Li6PS5Cl 0.9 I 0.1 66. The cell formation system of any one of embodiments 63 to 65, comprising a solid electrolyte selected from one or more of the following:

[0255] Embodiment 67. The cell formation system of any one of embodiments 63 to 66, wherein the separator or electrolyte comprises a solid lithium ion conductive ceramic.

[0256] Embodiment 68. The separator or electrolyte is LiClO4, LiBF4, LiPF6, LiAsF6, LiCl, and LiBr, as well as LiB(C6H5)4, LiN(SO2CF3)2, LiN(SO2CF3)3, LiNSO2CF3, LiNSO2CF5, LiNSO2C4F9, LiNSO2C5F 11 , LiNSO2C6F 13 , and LiNSO2C7F 15 68. The cell formation system of any one of embodiments 63-67, comprising a non-aqueous electrolyte selected from one or more of the following organic lithium salts:

[0257] Embodiment 69. The electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery is selected from the group consisting of: (a) silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), titanium (Ti), nickel (Ni), cobalt (Co), and cadmium (Cd); (b) alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Ni, Co, or Cd with other elements; (c) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Fe , Ni, Co, V, or Cd oxides, carbides, nitrides, sulfides, phosphides, selenides, and tellurides, and mixtures, composites, or lithium-containing composites thereof; (d) salts and hydroxides of Sn; (e) lithium titanate, lithium manganate, lithium aluminate, lithium-containing titanium oxides, lithium transition metal oxides, ZnCo2O4; (f) particles of graphite and carbon; (g) lithium metal; and (h) combinations thereof.

[0258] Embodiment 70. The cell formation system of any one of the preceding embodiments, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material selected from graphite, soft carbon, hard carbon, graphene, or any of the series of metals, semi-metals, alloys, oxides, nitrides, and compounds capable of intercalating or alloying with lithium.

[0259] Embodiment 71. The cell formation system of any one of the preceding embodiments, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material selected from tin, lead, magnesium, aluminum, boron, gallium, silicon, Si / C composites, Si / graphite blends, silicon oxide (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.

[0260] Embodiment 72. The cell formation system of any one of the preceding embodiments, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material selected from aluminum, tin, or silicon, or an oxide thereof, a nitride thereof, a fluoride thereof, or another alloy thereof.

[0261] Embodiment 73. The cell formation system of any one of the preceding embodiments, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material selected from fibers of aluminum, tin, or silicon, or alloys thereof.

[0262] Embodiment 74. The cell formation system of any one of the preceding embodiments, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material coated with a particulate lithium material selected from stabilized lithium metal particles.

[0263] Embodiment 75. The cell formation system of any one of the preceding embodiments, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises a cathode active material comprising an intercalation-type chemically active material, a conversion-type chemically active material, or a combination thereof.

[0264] Embodiment 76. The electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery is S, LiF, Fe, Cu, Ni, FeF2, FeO d F 3.2d , FeF3, CoF3, CoF2, CuF2, NiF2, wherein 0≦d≦0.5.

[0265] Embodiment 77. The cell formation system of any one of the preceding embodiments, wherein the electrode active material layer or counter electrode active material layer of the lithium-containing secondary battery comprises a negative electrode active material comprising one or more of a transition metal oxide, a transition metal sulfide, a transition metal nitride, a lithium-transition metal oxide, a lithium-transition metal sulfide, and a lithium-transition metal nitride.

[0266] Embodiment 78. A forming cluster for connection to a single lithium-containing secondary battery in a cell forming system for lithium-containing secondary batteries, each lithium-containing secondary battery including a bilayer group, an electrode bus bar, and a counter electrode bus bar, each bilayer of the bilayer group includes an electrode structure, a separator structure, and a counter electrode structure, the electrode structure of each member of the bilayer group includes an electrode current collector and an electrode active material layer, and the counter electrode structure of each member of the bilayer group includes a counter electrode current collector and a counter electrode active material layer. The forming cluster includes a connector configured to connect to the lithium-containing secondary battery, a charging module connected to the connector and charging the lithium-containing secondary battery connected to the connector, a pre-lithiation module connected to the connector and diffusing lithium into the electrode active material layer of the lithium-containing secondary battery connected to the connector, a discharging module connected to the connector and discharging the lithium-containing secondary battery connected to the connector, and at least one microcontroller. The at least one microcontroller is programmed to charge a lithium-containing secondary battery connected to the connector using the charging module, to diffuse lithium into an electrode active material layer of the lithium-containing secondary battery using the pre-lithiation module after the lithium-containing secondary battery is charged, and to discharge the lithium-containing secondary battery using the discharging module after lithium has been diffused into an electrode active material layer of the lithium-containing secondary battery using the pre-lithiation module.

[0267] Embodiment 79. A formation cluster as described in embodiment 78, further comprising a communication interface for communicatively coupling the formation cluster to a central controller.

[0268] Embodiment 80. The forming cluster of embodiment 79, wherein at least one microcontroller is programmed to charge, diffuse, and discharge the lithium-containing secondary battery in response to instructions received from the central controller.

[0269] Embodiment 81. A forming cluster as described in embodiment 79 or embodiment 80, wherein the communication interface is a wired communication interface for connecting to a wired communication network.

[0270] Embodiment 82. A forming cluster as described in embodiment 79 or 80, wherein the communication interface is a wireless communication interface for connecting to a wireless communication network.

[0271] Embodiment 83. A forming cluster described in any one of embodiments 78 to 82, further comprising a power connection configured for connection to a power source, the power connection being coupled to the charging module, the pre-lithiation module, and the discharge module.

[0272] Embodiment 84. The forming cluster described in any one of embodiments 78 to 83, wherein at least one microcontroller includes a charging module controller, a pre-lithiation module controller, and a discharging module controller.

[0273] Embodiment 85. The forming cluster of embodiment 84, wherein the charging module controller is programmed to control the charging module, the pre-lithiation module controller is programmed to control the pre-lithiation module, and the discharge module controller is programmed to control the discharge module.

[0274] Embodiment 86. A forming cluster described in any one of embodiments 78 to 85, further comprising at least one sensor for monitoring the status of the forming cluster or the lithium-containing secondary battery connected to the connector, and at least one microcontroller is programmed to receive a signal output by the at least one sensor.

[0275] Embodiment 87. The forming cluster described in embodiment 86, wherein at least one sensor includes a temperature sensor.

[0276] Embodiment 88. A forming cluster as described in embodiment 86 or embodiment 87, wherein at least one sensor includes a voltage sensor.

[0277] Embodiment 89. A forming cluster as described in embodiment 86, 87, or 88, wherein at least one sensor includes a current sensor.

[0278] Embodiment 90. The formed cluster of any one of embodiments 78 to 89, wherein the lithium-containing secondary battery connected to the connector includes an auxiliary electrode containing lithium, and the pre-lithiation module is configured to selectively conduct current through the auxiliary electrode to diffuse lithium into the electrode active material layer of the lithium-containing secondary battery.

[0279] Embodiment 91. The auxiliary electrode includes a first separator layer including an ion-permeable material, a conductive layer including a conductive material, the conductive layer having a first surface in contact with the first separator layer and a second surface opposite the first surface, a population of carrier ion supply layers disposed on the second surface of the conductive layer, each carrier ion supply layer including a material that supplies lithium ions to an electrode active material layer of a lithium-containing secondary battery, and a second separator layer including an ion-permeable material and in contact with the carrier ion supply layers.

[0280] Embodiment 92. The forming cluster of embodiment 91, wherein the second surface of the conductive layer includes a first region disposed at a first end of the conductive layer, a second region disposed at a second end of the conductive layer opposite the first end, and a third region disposed between the first region and the second region, and one of the carrier ion supply layers is disposed in the first region and another one of the carrier ion supply layers is disposed in the second region.

[0281] Embodiment 93. The formed clusters of embodiment 92, wherein the second separator layer is in contact with a third region of the second surface of the conductive layer.

[0282] Embodiment 94. The forming cluster of embodiment 91 or 92, wherein the first region, the second region, and the third region are disposed along the length of the conductive layer.

[0283] Embodiment 95. The formed cluster of any one of embodiments 91-94, wherein the first separator layer and the second separator layer are mechanically bonded together around at least a portion of the periphery of the first separator layer and the second separator layer.

[0284] Embodiment 96. A forming cluster according to any one of embodiments 91 to 95, wherein the first separator layer and the second separator layer are formed from a continuous separator material, the first separator layer comprising a first portion of the continuous separator material, and the second separator layer comprising a second portion of the continuous separator material, the second portion being folded over the first portion so as to contact the surface of the carrier ion supply layer.

[0285] Embodiment 97. The formed cluster of embodiment 96, wherein the continuous separator material has a thickness in the range of about 0.01 millimeters to about 1 millimeter.

[0286] Embodiment 98. The formed cluster of embodiment 97, wherein the thickness of the continuous separator material is about 0.025 millimeters.

[0287] Embodiment 99. The formed cluster of any one of embodiments 91-98, wherein the first separator layer and the second separator layer have a thickness within a range of values ​​from about 0.01 millimeters to about 1 millimeter.

[0288] Embodiment 100. The formed cluster of any one of embodiments 91-99, wherein the thickness of the second separator layer is about 0.025 millimeters.

[0289] Embodiment 101. The forming cluster of any one of embodiments 91 to 100, wherein the conductive layer comprises one of copper and aluminum, or an alloy of copper and aluminum.

[0290] Embodiment 102. The forming cluster of any one of embodiments 91 to 101, wherein the conductive layer comprises copper.

[0291] Embodiment 103. The formed cluster of any one of embodiments 91-102, wherein the conductive layer has a thickness within a range of values ​​from about 0.01 millimeters to about 1 millimeter.

[0292] Embodiment 104. The forming cluster of any one of embodiments 91 to 103, wherein the conductive layer has a thickness of about 0.1 millimeters.

[0293] Embodiment 105. The forming cluster according to any one of embodiments 91 to 104, wherein the carrier ion supply layer has a thickness within a range of values ​​from about 0.05 millimeters to about 1 millimeter.

[0294] Embodiment 106. The forming cluster of any one of embodiments 91 to 105, wherein the carrier ion supply layer has a thickness of about 0.15 millimeters.

[0295] Embodiment 107. The forming cluster of any one of embodiments 91-106, wherein the carrier ion supply layer provides a source of lithium ions.

[0296] Embodiment 108. The formed cluster of any one of embodiments 91 to 107, wherein the carrier ion supply layer is cold welded to the second surface of the conductive layer.

[0297] Embodiment 109. A formed cluster according to any one of embodiments 91 to 108, wherein the auxiliary pole comprises a conductive material and includes a conductive tab bonded to the second surface of the conductive layer.

[0298] Embodiment 110. The forming cluster described in embodiment 109, wherein the conductive tab includes a first end coupled to the conductive layer and a second end distal to the first end that protrudes away from the conductive layer.

[0299] Embodiment 111. The forming cluster of embodiment 109 or 110, wherein the conductive tab comprises one of nickel, copper, and aluminum, or an alloy of copper, nickel, and aluminum.

[0300] Embodiment 112. The forming cluster of embodiment 109 or 110, wherein the conductive tab comprises nickel.

[0301] Embodiment 113. A forming cluster described in any one of embodiments 78 to 112, wherein the electrode structure is one of a positive electrode and a negative electrode, and the counter electrode structure is the other of a positive electrode and a negative electrode, the positive electrode having a positive electrode coulombic capacity, and the negative electrode having a negative electrode coulombic capacity that exceeds the positive electrode coulombic capacity.

[0302] Embodiment 114. The formed clusters of embodiment 113, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 1.2:1.

[0303] Embodiment 115. The formed clusters of embodiment 113, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 1.3:1.

[0304] Embodiment 116. The formed clusters of embodiment 113, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 1.5:1.

[0305] Embodiment 117. The formed clusters of embodiment 113, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 2:1.

[0306] Embodiment 118. The formed clusters of embodiment 113, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 3:1.

[0307] Embodiment 119. The formed clusters of embodiment 113, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 4:1.

[0308] Embodiment 120. The formed clusters of embodiment 113, wherein the ratio of negative electrode coulombic capacity to positive electrode coulombic capacity is at least 5:1.

[0309] Embodiment 121. A forming cluster described in any one of embodiments 90 to 112, wherein the electrode structure is one of a positive electrode and a negative electrode, and the counter electrode structure is the other of a positive electrode and a negative electrode, the positive electrode having a positive electrode coulombic capacity, and the negative electrode having a negative electrode coulombic capacity that exceeds the positive electrode coulombic capacity.

[0310] Embodiment 122. The formed clusters of embodiment 121, wherein the ratio of the coulombic capacity of the negative electrode to the coulombic capacity of the positive electrode is at least 1.2:1, at least 1.3:1, at least 1.5:1, at least 2:1, at least 3:1, at least 4:1, or at least 5:1.

[0311] Embodiment 123. The formed clusters of embodiment 121 or 122, wherein the ratio of the coulombic capacity of the auxiliary electrode to the coulombic capacity of the positive electrode is at least 2:1.

[0312] Embodiment 124. The formed clusters of embodiment 121 or 122, wherein the ratio of the coulombic capacity of the auxiliary electrode to the coulombic capacity of the positive electrode is at least 3:1.

[0313] Embodiment 125. The formed clusters of embodiment 121 or 122, wherein the ratio of the coulombic capacity of the auxiliary electrode to the coulombic capacity of the positive electrode is at least 4:1.

[0314] Embodiment 126. The formed clusters of embodiment 121 or 122, wherein the ratio of the coulombic capacity of the auxiliary electrode to the coulombic capacity of the positive electrode is at least 5:1.

[0315] Embodiment 127. The formed cluster according to any one of embodiments 78 to 126, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises anode active silicon or an alloy thereof.

[0316] Embodiment 128. The formed clusters of any one of embodiments 78 to 127, wherein the electrode active material layer or counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material comprising silicon and contains a void volume fraction to accommodate volumetric expansion and contraction as lithium ions are incorporated into or leave the electrode active material layer or counter electrode active material layer during charge and discharge cycles of the lithium-containing secondary battery.

[0317] Embodiment 129. The forming clusters of embodiment 128, wherein the void volume fraction of the anode active material is at least 0.1.

[0318] Embodiment 130. The formed clusters of embodiment 128, wherein the void volume fraction of the anode active material is 0.8 or less.

[0319] Embodiment 131. The forming clusters of embodiment 128, wherein the void volume fraction of the anode active material is from about 0.15 to about 0.75.

[0320] Embodiment 132. The formed clusters of embodiment 128, wherein the void volume fraction of the anode active material is from about 0.2 to about 0.7.

[0321] Embodiment 133. The formed clusters of embodiment 128, wherein the void volume fraction of the anode active material is from about 0.25 to about 0.6.

[0322] Embodiment 134. The forming clusters of embodiment 128, wherein the anode active material comprises a macroporous, microporous, or mesoporous material layer, or a combination thereof.

[0323] Embodiment 135. The formed cluster of any one of embodiments 78 to 134, wherein the separator structure comprises a microporous separator permeated with an electrolyte between the electrode structure and the counter electrode structure.

[0324] Embodiment 136. The formed clusters of embodiment 135, wherein the separator or electrolyte comprises a polymer-based electrolyte selected from one or more of a PEO-based polymer electrolyte, a polymer-ceramic composite electrolyte, a polymer-ceramic composite electrolyte, and a polymer-ceramic composite electrolyte.

[0325] Embodiment 137. The separator or electrolyte is lithium lanthanum titanate (Li 0.34 La 0.56 TiO3), Al-doped lanthanum zirconate lithium (Li 6.24 La3Zr2Al 0.24 O 11.98 ), Ta-doped lithium lanthanum zirconate (Li 6.4 La3Zr 1.4 Ta 0.6 O 12 ), and lithium aluminum titanium phosphate (Li 1.4 Al 0.4 Ti 1.6 137. The forming cluster of embodiment 135 or 136, comprising an oxide-based electrolyte selected from one or more of: (PO4)3).

[0326] Embodiment 138. The separator or electrolyte is lithium tin sulfide (Li 10 SnP2S 12 ), lithium phosphorus sulfide (β-Li3PS4), and lithium sulfide chloride (Li6PS5Cl 0.9 I 0.1 138. The formed cluster of any one of embodiments 135-137, comprising a solid electrolyte selected from one or more of the following:

[0327] Embodiment 139. The formed clusters of any one of embodiments 135 to 138, wherein the separator or electrolyte comprises a solid lithium ion conducting ceramic.

[0328] Embodiment 140. The separator or electrolyte is selected from the group consisting of LiClO4, LiBF4, LiPF6, LiAsF6, LiCl, and LiBr, as well as LiB(C6H5)4, LiN(SO2CF3)2, LiN(SO2CF3)3, LiNSO2CF3, LiNSO2CF5, LiNSO2C4F9, LiNSO2C5F 11 , LiNSO2C6F 13 , and LiNSO2C7F 15 140. The forming cluster of any one of embodiments 135-139, comprising a non-aqueous electrolyte selected from one or more of the following organic lithium salts:

[0329] Embodiment 141. The electrode active material layer or the counter electrode active material layer of a lithium-containing secondary battery is selected from the group consisting of: (a) silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), titanium (Ti), nickel (Ni), cobalt (Co), and cadmium (Cd); (b) alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Ni, Co, or Cd with other elements; (c) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Fe 141. The formed cluster of any one of embodiments 78-140, comprising an anode active material selected from: (a) oxides, carbides, nitrides, sulfides, phosphides, selenides, and tellurides of Ni, Co, V, or Cd, and mixtures, composites, or lithium-containing composites thereof; (b) salts and hydroxides of Sn; (c) lithium titanates, lithium manganates, lithium aluminates, lithium-containing titanium oxides, lithium transition metal oxides, ZnCo2O4; (d) particles of graphite and carbon; (e) lithium metal; and (f) combinations thereof.

[0330] Embodiment 142. The forming cluster according to any one of embodiments 78 to 141, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material selected from graphite, soft carbon, hard carbon, graphene, or any one of a series of metals, semi-metals, alloys, oxides, nitrides, and compounds capable of intercalating lithium or forming an alloy with lithium.

[0331] Embodiment 143. The forming cluster according to any one of embodiments 78 to 142, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material selected from tin, lead, magnesium, aluminum, boron, gallium, silicon, Si / C composites, Si / graphite blends, silicon oxide (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.

[0332] Embodiment 144. The forming cluster according to any one of embodiments 78 to 143, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material selected from aluminum, tin, or silicon, or an oxide thereof, a nitride thereof, a fluoride thereof, or another alloy thereof.

[0333] Embodiment 145. The formed cluster according to any one of embodiments 78 to 144, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material selected from fibers of aluminum, tin, or silicon, or alloys thereof.

[0334] Embodiment 146. The formed clusters according to any one of embodiments 78 to 145, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material coated with a particulate lithium material selected from stabilized lithium metal particles.

[0335] Embodiment 147. The formed clusters according to any one of embodiments 78 to 146, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises a cathode active material comprising an intercalation-type chemically active material, a conversion-type chemically active material, or a combination thereof.

[0336] Embodiment 148. The electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery is S, LiF, Fe, Cu, Ni, FeF2, FeO d F 3.2d , FeF3, CoF3, CoF2, CuF2, NiF2, wherein 0≦d≦0.5.

[0337] Embodiment 149. The forming clusters according to any one of embodiments 78 to 148, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises a negative electrode active material comprising one or more of a transition metal oxide, a transition metal sulfide, a transition metal nitride, a lithium-transition metal oxide, a lithium-transition metal sulfide, and a lithium-transition metal nitride.

[0338] Embodiment 150. A distributed cell formation system for lithium-containing secondary batteries, each lithium-containing secondary battery including a population of bilayers, an electrode busbar, and a counter electrode busbar, each bilayer of the population of bilayers including an electrode structure, a separator structure, and a counter electrode structure, the electrode structure of each member of the bilayer population including an electrode current collector and an electrode active material layer, and the counter electrode structure of each member of the bilayer population including a counter electrode current collector and a counter electrode active material layer. The distributed cell formation system includes a central controller including a processor, a memory, and a communication interface, and a population of formation clusters positioned remotely from the central controller. Each formation cluster is configured to perform a plurality of steps of a cell formation process for a single lithium-containing secondary battery, each formation cluster including a connector configured for connecting to a lithium-containing secondary battery, a population of modules, each module of the population of modules configured to perform a different one of the plurality of steps on a lithium-containing secondary battery connected to the connector, a communication interface communicatively coupled to the central controller, and at least one microcontroller. At least one microcontroller is programmed to control the population of modules to perform a number of steps of a cell formation process in response to instructions received from the central controller.

[0339] Embodiment 151. A distributed cell formation system as described in embodiment 150, wherein the multiple steps of the cell formation process include charging a lithium-containing secondary battery connected to the connector and discharging a lithium-containing secondary battery connected to the connector.

[0340] Embodiment 152. A distributed cell formation system as described in embodiment 150, wherein the multiple steps of the cell formation process include diffusing lithium into an electrode active material layer of a lithium-containing secondary battery connected to a connector.

[0341] Embodiment 153. A distributed cell formation system as described in embodiment 151, wherein the multiple steps of the cell formation process include diffusing lithium into an electrode active material layer of a lithium-containing secondary battery connected to a connector.

[0342] Embodiment 154. A distributed cell formation system as described in embodiment 153, wherein at least one microcontroller is programmed to control the population of modules to first charge a lithium-containing secondary battery connected to the connector, diffuse lithium into an electrode active material layer of the lithium-containing secondary battery connected to the connector after the lithium-containing secondary battery is charged, and discharge the lithium-containing secondary battery after diffusing lithium into the electrode active material layer of the lithium-containing secondary battery.

[0343] Embodiment 155. A distributed cell formation system described in any one of embodiments 150 to 154, further comprising a housing, wherein the group of formation clusters are located within the housing, and the central controller is not located within the housing.

[0344] Embodiment 156. A distributed cell formation system described in any one of embodiments 150 to 155, wherein at least one microcontroller includes a memory storing instructions executable by the at least one microcontroller to control the performance of multiple steps by a population of modules.

[0345] Embodiment 157. A distributed cell formation system as described in embodiment 156, wherein the central controller is programmed by instructions stored in the memory to transmit instructions to each forming cluster using a communication interface, the instructions informing each forming cluster when to perform each step of the multiple steps without informing the forming cluster how to perform each step.

[0346] Embodiment 158. A distributed cell formation system as described in embodiment 156, wherein the central controller is programmed by instructions stored in the memory to transmit instructions to each formation cluster using a communication interface for controlling the performance of multiple steps by a group of modules.

[0347] Embodiment 159. A distributed cell formation system described in any one of embodiments 150 to 158, wherein at least one microcontroller includes a population of module controllers, each module controller of the population of module controllers being programmed to control a different one of the modules to perform its associated one of the plurality of steps.

[0348] Embodiment 160. A distributed cell formation system as described in embodiment 159, wherein each module controller includes a microcontroller.

[0349] Embodiment 161. A distributed cell formation system described in any one of embodiments 150 to 160, wherein the lithium-containing secondary battery connected to the connector of each forming cluster includes an auxiliary electrode containing lithium, and each forming cluster is configured to selectively conduct current through its respective auxiliary electrode to diffuse lithium into the electrode active material layer of the lithium-containing secondary battery.

[0350] Embodiment 162. The distributed cell formation system described in embodiment 161, wherein the auxiliary electrode includes a first separator layer including an ion-permeable material, a conductive layer including a conductive material, the conductive layer having a first surface in contact with the first separator layer and a second surface opposite the first surface, a population of carrier ion supply layers disposed on the second surface of the conductive layer, each carrier ion supply layer including a material that supplies lithium ions to an electrode active material layer of a lithium-containing secondary battery, and a second separator layer including an ion-permeable material and in contact with the carrier ion supply layers.

[0351] Embodiment 163. A distributed cell formation system as described in embodiment 162, wherein the second surface of the conductive layer includes a first region disposed at a first end of the conductive layer, a second region disposed at a second end of the conductive layer opposite the first end, and a third region disposed between the first region and the second region, and one of the carrier ion supply layers is disposed within the first region and another one of the carrier ion supply layers is disposed within the second region.

[0352] Embodiment 164. The dispersed cell formation system of embodiment 163, wherein the second separator layer is in contact with a third region of the second surface of the conductive layer.

[0353] Embodiment 165. A distributed cell formation system as described in embodiment 163 or 164, wherein the first region, the second region, and the third region are disposed along the length of the conductive layer.

[0354] Embodiment 166. A distributed cell formation system described in any one of embodiments 162 to 165, wherein the first separator layer and the second separator layer are mechanically joined together around at least a portion of the periphery of the first separator layer and the second separator layer.

[0355] Embodiment 167. A distributed cell formation system described in any one of embodiments 162 to 166, wherein the first separator layer and the second separator layer are formed from a continuous separator material, the first separator layer comprising a first portion of the continuous separator material, and the second separator layer comprising a second portion of the continuous separator material, the second portion being folded over the first portion so as to contact the surface of the carrier ion supply layer.

[0356] Embodiment 168. A distributed cell formation system as described in embodiment 167, wherein the continuous separator material has a thickness in the range of about 0.01 millimeters to about 1 millimeter.

[0357] Embodiment 169. A distributed cell formation system as described in embodiment 168, wherein the thickness of the continuous separator material is about 0.025 millimeters.

[0358] Embodiment 170. A distributed cell formation system described in any one of embodiments 162 to 169, wherein the first separator layer and the second separator layer have a thickness within a range of values ​​from about 0.01 millimeters to about 1 millimeter.

[0359] Embodiment 171. A distributed cell formation system described in any one of embodiments 162 to 170, wherein the thickness of the second separator layer is about 0.025 millimeters.

[0360] Embodiment 172. A distributed cell formation system described in any one of embodiments 162 to 171, wherein the conductive layer comprises one of copper and aluminum, or an alloy of copper and aluminum.

[0361] Embodiment 173. A distributed cell formation system according to any one of embodiments 162 to 172, wherein the conductive layer comprises copper.

[0362] Embodiment 174. A distributed cell formation system described in any one of embodiments 162 to 173, wherein the conductive layer has a thickness within a range of values ​​from about 0.01 millimeters to about 1 millimeter.

[0363] Embodiment 175. A distributed cell formation system described in any one of embodiments 162 to 174, wherein the conductive layer has a thickness of about 0.1 millimeters.

[0364] Embodiment 176. A distributed cell formation system described in any one of embodiments 162 to 175, wherein the carrier ion supply layer has a thickness within a range of values ​​from about 0.05 millimeters to about 1 millimeter.

[0365] Embodiment 177. A distributed cell formation system described in any one of embodiments 162 to 176, wherein the carrier ion supply layer has a thickness of about 0.15 millimeters.

[0366] Embodiment 178. A distributed cell formation system according to any one of embodiments 162 to 177, wherein the carrier ion supply layer provides a source of lithium ions.

[0367] Embodiment 179. A distributed cell formation system described in any one of embodiments 162 to 178, wherein the carrier ion supply layer is cold welded to the second surface of the conductive layer.

[0368] Embodiment 180. A distributed cell formation system described in any one of embodiments 162 to 179, wherein the auxiliary electrode comprises a conductive material and includes a conductive tab bonded to the second surface of the conductive layer.

[0369] Embodiment 181. A distributed cell formation system as described in embodiment 180, wherein the conductive tab includes a first end coupled to the conductive layer and a second end distal to the first end that protrudes away from the conductive layer.

[0370] Embodiment 182. A distributed cell formation system as described in embodiment 180 or 181, wherein the conductive tab comprises one of nickel, copper, and aluminum, or an alloy of copper, nickel, and aluminum.

[0371] Embodiment 183. The dispersed cell formation system of embodiment 180 or 181, wherein the conductive tab comprises nickel.

[0372] Embodiment 184. A distributed cell formation system described in any one of embodiments 150 to 183, wherein the electrode structure is one of a positive electrode and a negative electrode, and the counter electrode structure is the other of a positive electrode and a negative electrode, the positive electrode having a positive electrode coulombic capacity, and the negative electrode having a negative electrode coulombic capacity that exceeds the positive electrode coulombic capacity.

[0373] Embodiment 185. The dispersed cell formation system of embodiment 184, wherein the ratio of the negative electrode coulombic capacity to the positive electrode coulombic capacity is at least 1.2:1.

[0374] Embodiment 186. The dispersed cell formation system of embodiment 184, wherein the ratio of the negative electrode coulombic capacity to the positive electrode coulombic capacity is at least 1.3:1.

[0375] Embodiment 187. The dispersed cell formation system of embodiment 184, wherein the ratio of the negative electrode coulombic capacity to the positive electrode coulombic capacity is at least 1.5:1.

[0376] Embodiment 188. The dispersed cell formation system of embodiment 184, wherein the ratio of the negative electrode coulombic capacity to the positive electrode coulombic capacity is at least 2:1.

[0377] Embodiment 189. The dispersed cell formation system of embodiment 184, wherein the ratio of the negative electrode coulombic capacity to the positive electrode coulombic capacity is at least 3:1.

[0378] Embodiment 190. The dispersed cell formation system of embodiment 184, wherein the ratio of the negative electrode coulombic capacity to the positive electrode coulombic capacity is at least 4:1.

[0379] Embodiment 191. The dispersed cell formation system of embodiment 184, wherein the ratio of the negative electrode coulombic capacity to the positive electrode coulombic capacity is at least 5:1.

[0380] Embodiment 192. A distributed cell formation system described in any one of embodiments 161 to 183, wherein the electrode structure is one of a positive electrode and a negative electrode, and the counter electrode structure is the other of a positive electrode and a negative electrode, the positive electrode having a positive electrode coulombic capacity, and the negative electrode having a negative electrode coulombic capacity that exceeds the positive electrode coulombic capacity.

[0381] Embodiment 193. The dispersed cell formation system of embodiment 192, wherein the ratio of the coulombic capacity of the negative electrode to the coulombic capacity of the positive electrode is at least 1.2:1, at least 1.3:1, at least 1.5:1, at least 2:1, at least 3:1, at least 4:1, or at least 5:1.

[0382] Embodiment 194. A distributed cell formation system as described in embodiment 192 or 193, wherein the ratio of the coulombic capacity of the auxiliary electrode to the positive electrode coulombic capacity is at least 2:1.

[0383] Embodiment 195. A distributed cell formation system as described in embodiment 192 or 193, wherein the ratio of the coulombic capacity of the auxiliary electrode to the positive electrode coulombic capacity is at least 3:1.

[0384] Embodiment 196. A distributed cell formation system according to embodiment 192 or 193, wherein the ratio of the coulombic capacity of the auxiliary electrode to the positive electrode coulombic capacity is at least 4:1.

[0385] Embodiment 197. A distributed cell formation system as described in embodiment 192 or 193, wherein the ratio of the coulombic capacity of the auxiliary electrode to the positive electrode coulombic capacity is at least 5:1.

[0386] Embodiment 198. The distributed cell formation system according to any one of embodiments 150 to 197, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises anode active silicon or an alloy thereof.

[0387] Embodiment 199. A dispersed cell formation system according to any one of embodiments 150 to 198, wherein the electrode active material layer or counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material comprising silicon and contains a void volume fraction to accommodate volumetric expansion and contraction as lithium ions are incorporated into or separated from the electrode active material layer or counter electrode active material layer during charge and discharge cycles of the lithium-containing secondary battery.

[0388] Embodiment 200. The dispersed cell formation system of embodiment 199, wherein the void volume fraction of the anode active material is at least 0.1.

[0389] Embodiment 201. The dispersed cell formation system of embodiment 199, wherein the void volume fraction of the anode active material is 0.8 or less.

[0390] Embodiment 202. The dispersed cell formation system of embodiment 199, wherein the void volume fraction of the anode active material is about 0.15 to about 0.75.

[0391] Embodiment 203. The dispersed cell formation system of embodiment 199, wherein the void volume fraction of the anode active material is about 0.2 to about 0.7.

[0392] Embodiment 204. The dispersed cell formation system of embodiment 199, wherein the void volume fraction of the anode active material is about 0.25 to about 0.6.

[0393] Embodiment 205. The dispersed cell formation system of embodiment 199, wherein the anode active material comprises a macroporous, microporous, or mesoporous material layer, or a combination thereof.

[0394] Embodiment 206. A dispersed cell formation system according to any one of embodiments 150 to 205, wherein the separator structure includes a microporous separator permeated with an electrolyte between the electrode structure and the counter electrode structure.

[0395] Embodiment 207. A dispersed cell formation system as described in embodiment 206, wherein the separator or electrolyte comprises a polymer-based electrolyte selected from one or more of a PEO-based polymer electrolyte, a polymer-ceramic composite electrolyte, a polymer-ceramic composite electrolyte, and a polymer-ceramic composite electrolyte.

[0396] Embodiment 208. The separator or electrolyte is lithium lanthanum titanate (Li 0.34 La 0.56 TiO3), Al-doped lanthanum zirconate lithium (Li 6.24 La3Zr2Al 0.24 O 11.98 ), Ta-doped lithium lanthanum zirconate (Li 6.4 La3Zr 1.4 Ta 0.6 O 12 ), and lithium aluminum titanium phosphate (Li 1.4 Al 0.4 Ti1.6 208. The dispersed cell formation system of embodiment 206 or 207, comprising an oxide-based electrolyte selected from one or more of: (PO4)3).

[0397] Embodiment 209. The separator or electrolyte is lithium tin sulfide (Li 10 SnP2S 12 ), lithium phosphorus sulfide (β-Li3PS4), and lithium sulfide chloride (Li6PS5Cl 0.9 I 0.1 209. The distributed cell formation system according to any one of embodiments 206 to 208, comprising a solid electrolyte selected from one or more of the following:

[0398] Embodiment 210. A distributed cell formation system according to any one of embodiments 206 to 209, wherein the separator or electrolyte comprises a solid lithium ion conductive ceramic.

[0399] Embodiment 211. The separator or electrolyte is LiClO4, LiBF4, LiPF6, LiAsF6, LiCl, and LiBr, as well as LiB(C6H5)4, LiN(SO2CF3)2, LiN(SO2CF3)3, LiNSO2CF3, LiNSO2CF5, LiNSO2C4F9, LiNSO2C5F 11 , LiNSO2C6F 13 , and LiNSO2C7F 15 211. The dispersed cell formation system according to any one of embodiments 206 to 210, comprising a non-aqueous electrolyte selected from one or more of the organic lithium salts such as:

[0400] Embodiment 212. The electrode active material layer or the counter electrode active material layer of a lithium-containing secondary battery is selected from the group consisting of: (a) silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), titanium (Ti), nickel (Ni), cobalt (Co), and cadmium (Cd); (b) alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Ni, Co, or Cd with other elements; (c) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Fe, Ni 212. The dispersed cell formation system of any one of embodiments 150 to 211, comprising an anode active material selected from: (a) oxides, carbides, nitrides, sulfides, phosphides, selenides, and tellurides of Co, V, or Cd, and mixtures, composites, or lithium-containing composites thereof; (b) salts and hydroxides of Sn; (c) lithium titanates, lithium manganates, lithium aluminates, lithium-containing titanium oxides, lithium transition metal oxides, ZnCo2O4; (d) particles of graphite and carbon; (e) lithium metal; and (f) combinations thereof.

[0401] Embodiment 213. The distributed cell formation system of any one of embodiments 150 to 212, wherein the electrode active material layer or counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material selected from graphite, soft carbon, hard carbon, graphene, or any one of a series of metals, semi-metals, alloys, oxides, nitrides, and compounds capable of intercalating lithium or forming an alloy with lithium.

[0402] Embodiment 214. The distributed cell formation system according to any one of embodiments 150 to 213, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material selected from tin, lead, magnesium, aluminum, boron, gallium, silicon, Si / C composites, Si / graphite blends, silicon oxide (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.

[0403] Embodiment 215. The distributed cell formation system of any one of embodiments 150 to 214, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material selected from aluminum, tin, or silicon, or an oxide thereof, a nitride thereof, a fluoride thereof, or another alloy thereof.

[0404] Embodiment 216. A distributed cell formation system according to any one of embodiments 150 to 215, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material selected from fibers of aluminum, tin, or silicon, or alloys thereof.

[0405] Embodiment 217. The distributed cell formation system of any one of embodiments 150 to 216, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises an anode active material coated with a particulate lithium material selected from stabilized lithium metal particles.

[0406] Embodiment 218. The distributed cell formation system of any one of embodiments 150 to 217, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises a cathode active material comprising an intercalation-type chemically active material, a conversion-type chemically active material, or a combination thereof.

[0407] Embodiment 219. The electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery is S, LiF, Fe, Cu, Ni, FeF2, FeO d F 3.2d , FeF3, CoF3, CoF2, CuF2, NiF2, wherein 0≦d≦0.5.

[0408] Embodiment 220. The distributed cell formation system of any one of embodiments 150 to 219, wherein the electrode active material layer or the counter electrode active material layer of the lithium-containing secondary battery comprises a negative electrode active material comprising one or more of a transition metal oxide, a transition metal sulfide, a transition metal nitride, a lithium-transition metal oxide, a lithium-transition metal sulfide, and a lithium-transition metal nitride.

[0409] This written specification uses examples to disclose the invention, including the best mode, and also enables any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal words of the claims, or if they include equivalent structural elements with differences that do not differ insubstantially from the literal words of the claims.

Claims

1. A device for buffering a battery, the device comprising: a connector configured to be operably coupled to the battery; a charging module operably coupled to the connector and configured to charge the battery; a pre-lithiation module operably coupled to the connector and configured to diffuse lithium ions into the electrode active material of the battery; a discharging module operably coupled to the connector and configured to discharge the battery.

2. The device according to claim 1, wherein the pre-lithiation module is configured to diffuse lithium ions into the electrode active material of the battery after the battery is charged.

3. The device according to claim 1, wherein the discharging module is configured to discharge the battery after lithium ions are diffused into the electrode active material of the battery.

4. The device according to claim 1, comprising a plurality of forming clusters including a forming cluster similar to the forming cluster having the connector, the charging module, the pre-lithiation module, and the discharging module.

5. The battery comprises a double layer having an electrode, a separator, and a counter electrode in each double layer, and (A) the electrode of each member of the double layer has an electrode current collector coupled to an electrode active material, and / or (B) the counter electrode of each member of the double layer has a counter electrode current collector coupled to a counter electrode active material. The device according to claim 1.

6. The device according to claim 5, wherein the battery comprises an electrode bus bar coupled to the electrode of each double layer and / or a counter electrode bus bar coupled to the counter electrode of each double layer.

7. The device according to claim 1, further comprising at least one sensor, the at least one sensor being operably coupled to at least one controller programmed to receive a signal output by the at least one sensor and transmit the received signal, the at least one controller being configured to control a forming cluster having the connector, the charging module, the pre-lithiation module, and the discharging module.

8. The device according to claim 7, wherein the at least one sensor includes a temperature sensor, a voltage sensor, a current sensor, or any combination thereof.

9. The device according to claim 1, wherein the battery has an anode active material having silicon, graphite, a composite material, a blend material, carbon nanotubes, or any combination thereof, and optionally, the anode active material has silicon oxide, a silicon-carbon composite material, a silicon-graphite blend, or any combination thereof.

10. The device according to claim 1, wherein the device is configured to be coupled to an auxiliary electrode to generate the lithium ions from the auxiliary electrode.

11. The device according to claim 10, wherein the device is configured to couple to the auxiliary electrode that is coupled to the battery, and optionally, the auxiliary electrode couples to the battery on an opposite side of the battery.

12. The device according to claim 11, wherein the device is configured to couple to the battery and the auxiliary electrode placed in a pouch.

13. The device according to claim 12, wherein the device is configured to couple to the battery and the auxiliary electrode placed in a sealed pouch.

14. The device according to claim 13, wherein the pouch is at least partially sealed by being liquid-tight and / or air-tight.

15. The device according to claim 1, wherein the battery includes a constraint portion surrounding one or more unit cells of the battery, the constraint portion is configured to house the battery and facilitate the distribution or flow of an electrolyte solution, and the electrolyte solution carries the lithium ions.

16. The device according to claim 15, wherein the distribution or flow of the electrolyte solution is performed through perforations in the constraint portion.

17. The device according to claim 1, further comprising a housing that supports a forming cluster having the connector, the charging module, the pre-lithiation module, and the discharging module.

18. A method for buffering a battery, comprising: (a) providing a device according to any one of claims 1 to 17; and (b) performing one or more operations associated with the device to buffer the battery.

19. An apparatus for buffering the battery, comprising at least one controller operably coupled to the device according to any one of Claims 1 to 17 and configured to perform or direct the performance of the operations of the device, and optionally, the at least one controller includes at least one microcontroller and / or a central controller.

20. Non-transitory computer-readable program instructions physically inscribed on at least one medium, which when read by one or more processors operably coupled to the device according to any one of Claims 1 to 17, cause the one or more processors to perform one or more operations related to the device for buffering the battery.

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