Apparatus for use with electrochemical cells

Abstract

The present invention provides an apparatus for homogenizing one or more regions within a plurality of electrochemical cells, comprising a plurality of magnetic flux generators, each configured to generate a variable magnetic field passing through at least one of the plurality of electrochemical cells, wherein the plurality of magnetic flux generators and the plurality of electrochemical cells are arranged alternately.

Description

Technical Field

[0001] The present invention relates to an apparatus for homogenizing one or more regions within a plurality of electrochemical cells.

Background Art

[0002] Electrochemical cells are essential for many electrical systems, including portable devices such as mobile phones and laptops, electric vehicles, and stationary devices and systems such as stationary home energy storage.

[0003] Various types and configurations of electrochemical cells can be selected based on size, shape, voltage, current, and other requirements. Examples of common cell shapes include pouch cells, prismatic cells, cylindrical cells, and coin cells. Cells can also be connected in series or parallel arrangements to form batteries that can provide appropriate voltage and / or current for the application.

[0004] Generally, it is desirable to have cells with large capacity and short charging time in order to increase the ratio of the time the device can operate independently of an external power source to the time the device must be connected to an external power source for charging.

[0005] The performance and / or lifespan of electrochemical cells are related to the quality of their structure. Specifically, heterogeneous structures (e.g., resulting from heterogeneous layer deposition / removal during cell formation and / or cell operation) can impair the performance and / or lifespan of cells. Electrochemical cells (such as lithium-ion batteries) typically have a layered structure that includes, for example, interfacial layers that act to passivate electrochemically active interfacial surfaces within the cell. These layers are typically deposited / removed under electrochemical conditions during cell formation and / or cell operation. However, ensuring the homogeneity of the layer structure under these conditions can be challenging. It is known that the quality of the cell's layer structure can dramatically affect cell performance as well as the feasibility and economics of the electrochemical process. For example, in the context of lithium-ion batteries, it is essential that interfacial layer formation during cell formation (i.e., during Formation Aging & Testing (FA&T)) and cell operation is reliably controlled to ensure safe and efficient cell operation. [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] Therefore, since the quality of the cell's internal structure can dramatically affect its performance and / or lifespan, it is crucial to be able to reliably control the homogeneity of the regions within the cell during cell formation and / or cell operation. [Means for solving the problem]

[0007] In view of the above considerations, the present invention was devised.

[0008] In a first aspect, the present invention relates to an apparatus for homogenizing one or more regions within a plurality of electrochemical cells, It comprises multiple magnetic flux generators, each configured to generate its own changing magnetic field passing through at least one of multiple electrochemical cells, The apparatus provides a configuration in which multiple magnetic flux generators and multiple electrochemical cells are arranged alternately.

[0009] Therefore, the apparatus is configured to homogenize one or more regions within each of multiple electrochemical cells by ensuring that layer deposition / removal (during cell formation and / or operation) occurs under magnetoelectrochemical conditions. This is achieved by providing a respective changing magnetic field through (i.e., transmitted through) each cell. Advantageously, providing a changing magnetic field through the electrochemical cells increases the homogeneity of layers within the cells (e.g., solid electrolyte interfaces (SEIs)) by increasing the homogeneity of local resistances within the cells. Furthermore, layer deposition / removal under magnetoelectrochemical conditions can also increase the rate of layer formation / removal. Thus, the apparatus ensures that the performance of the cells can be improved by homogenizing one or more regions within multiple cells during cell formation and / or cell operation, and layers may be formed / removed more rapidly.

[0010] Furthermore, the apparatus may be configured such that the spatial and / or temporal relationships between multiple flux generators are controlled to prevent destructive interference between the multiple, each of the changing magnetic fields. The desired spatial and / or temporal relationships can be modeled using known computer techniques.

[0011] The optional features of the present invention are discussed below. The present invention includes combinations of the described embodiments and optional features, unless such combinations are clearly unacceptable or explicitly avoided.

[0012] Each of these electrochemical cells can be a battery. Each of these electrochemical cells can be a cation cell, and the current path can be in the direction of cation movement. Alternatively, each of these electrochemical cells can be an anion cell, and the current path can be in the direction of anion movement. Each of these electrochemical cells can be a lithium-ion battery. Each of these electrochemical cells can be a solid-state battery.

[0013] The changing magnetic field generated by at least one of the one or more flux generators may have a frequency of at least 0.1 Hz, or at least 1 Hz, or at least 5 Hz, or at least 10 Hz, or at least 20 Hz, or at least 50 Hz, or at least 75 Hz, or at least 100 Hz, or at least 125 Hz. Alternatively, or in addition, the changing magnetic field generated by at least one of the one or more flux generators may have a frequency of 1000 Hz or less, or 750 Hz or less, or 500 Hz or less, or 250 Hz or less, or 150 Hz or less, or 100 Hz or less.

[0014] The apparatus may comprise one or more cell stations, each configured to house a plurality of electrochemical cells. Each cell station may include cell trays and / or cell containers for supporting the plurality of electrochemical cells. For example, each cell tray / cell container may be formed from a magnetosensitive material to guide the magnetic field toward a preferred location, for example, to localize and isolate the magnetic field relative to each cell tray / cell container, thereby maximizing control over the magnetic field structure and minimizing stray magnetic field losses to the local environment.

[0015] Multiple flux generators may be arranged inside each cell station such that each cell station contains at least one of the multiple flux generators. If the flux generators are arranged inside each cell station and each cell station contains its own cell tray and / or cell container, the flux generators may also be supported by their respective cell trays and / or cell containers.

[0016] Each cell station may contain at least the same number of flux generators as electrochemical cells. The flux generators and electrochemical cells within each cell station may be arranged alternately. For example, the flux generators and electrochemical cells within each cell station may be arranged such that each cell is sandwiched between its pair of flux generators and vice versa. Conveniently, this can ensure that the electrochemical cells within each cell station are uniformly permeated by their respective changing magnetic fields.

[0017] One or more cell stations may be multiple cell stations. The cell stations can be arranged in a grid / array and / or stacked so as to be aligned vertically. Conveniently, this allows the cell stations to be placed in large-scale cell manufacturing facilities (e.g., gigafactories) and / or stationary home energy storage (e.g., on shelves inside towers) to simultaneously expose a large number of electrochemical cells to a changing magnetic field and realize the advantageous effects of the present invention.

[0018] Multiple flux generators may be interspersed between multiple cell stations. The flux generators and cell stations may be arranged such that each cell station is sandwiched between its respective pair of flux generators. Conveniently, this can ensure that the electrochemical cells within each cell station are uniformly permeated by their respective changing magnetic fields.

[0019] Multiple cell stations may be housed inside a container having one or more walls, and at least one of the multiple flux generators may be positioned outside the container, adjacent to each of the one or more walls of the container. For example, each flux generator may be in contact with each wall of the container, or each flux generator may be adjacent to each wall of the container so as to extend along a plane substantially parallel to the walls of the container and at a close distance from the walls of the container.

[0020] The apparatus may include at least one power supply configured to power multiple electrochemical cells. If the apparatus includes multiple cell stations, the at least one power supply can be multiple power supplies, each configured to power an electrochemical cell within each of the multiple cell stations. Such a configuration can ensure improved controllability of the process of homogenizing one or more regions within multiple electrochemical cells, as the power requirements of the various cell stations are independent of each other.

[0021] The above-mentioned at least one power source may be further configured to supply power to multiple flux generators.

[0022] Each flux generator may be connected to a shared or individual power supply and receive power from a shared or individual power supply, which is different from the at least one power source mentioned above. Providing a shared or individual power supply, different from the at least one power source mentioned above, for each flux generator can conveniently ensure that the power requirements of the electrochemical cell are independent of the power requirements of the flux generator. This can improve the controllability of the changing magnetic field generated.

[0023] If each flux generator can be connected to a shared power supply, a subset of multiple flux generators may each be connected to the shared power supply via their respective shared electrical connections.

[0024] Each changing magnetic field may be one or any combination of a rotating magnetic field, a pulsed magnetic field, and / or a vibrating magnetic field. The rotation of each changing magnetic field can be about an axis having a component perpendicular to the direction of each changing magnetic field. The rotation of each changing magnetic field can be about an axis having a component parallel to the direction of each changing magnetic field. The rotation of each changing magnetic field can be about an axis having a component perpendicular to the direction of the current flow within each electrochemical cell. The rotation of each changing magnetic field can be about an axis having a component parallel to the direction of the current flow of each electrochemical cell. Each rotating magnetic field can be provided by a rotating permanent magnet, or a temporary magnet, or an electromagnet, or by an array of electromagnets that are sequentially activated to effectively rotate each magnetic field.

[0025] Each changing magnetic field may be controllably variable in one, two, or three spatial dimensions. Additionally or alternatively, the polarity and / or magnitude of each magnetic field may be controllably variable.

[0026] Each magnetic flux generator may include one or more magnetic field sources.

[0027] At least one of the one or more magnetic field sources may include a permanent magnet and each mechanism for moving one or more of the permanent magnet and / or the electrochemical cell. For example, the mechanism can be an electric motor. Generally, when a changing magnetic field is generated by moving a permanent magnet, the changing magnetic field can be changed by changing the direction and / or speed in which the permanent magnet is moved by each mechanism. To completely "switch off" the temporary nature of the permanent magnet, the permanent magnet is kept in a stationary state. If the device includes a controller as described below, the controller can be configured to control a mechanism (e.g., an electric motor) to control the characteristics (e.g., frequency and / or direction) of the changing magnetic field generated by the magnetic flux generator.

[0028] At least one of the one or more magnetic field sources may be an electromagnet. The electromagnet can be of any type. Generally, an electromagnet includes a coil of wire wound around a core. The core can be formed from a high permeability magnetic material. The core can be a metal core (e.g., a ferromagnetic core). Alternatively, the core can be an air-filled space, i.e., an air core, in the center of the electromagnet. Each electromagnet can be connected to a common or respective power supply as discussed above. The magnetic field generated by each electromagnet can be changed by changing the amount and / or direction of the current supplied to the electromagnet by the power supply. For example, it may be desirable to switch off (i.e., not supply power to) one or more of the electromagnets to change the changing magnetic field generated by each magnetic flux generator. Additionally or alternatively, for example, it may be desirable to supply currents having various directions and / or magnitudes to the respective various electromagnets to change the polarity of the magnetic field of each generated magnetic field.

[0029] When the device includes a controller as described below, the controller can be configured to control the current supplied to the magnetic flux generator to control the characteristics of the generated changing magnetic field. In some examples, the controller is configured to control the amount and / or direction and / or frequency of the current supplied to one or more magnetic flux generators by its / each power supply, and / or to switch off the power supply to a selected magnetic flux generator(s) among the magnetic flux generators. In some examples, the controller can be configured to cause its / each power supply to supply currents having various directions and / or magnitudes and / or frequencies to a selected magnetic flux generator(s) among the magnetic flux generators (in this case, electromagnets).

[0030] Each electromagnet may be an air-core electromagnet extending longitudinally (i.e., axially) and radially to define space for housing each of the multiple electrochemical cells. The electrochemical cells may be cylindrical. An air-core electromagnet, here, means a coil of wire (i.e., a solenoid), which includes an air-filled central space defined by the coil and does not include a solid core such as a ferromagnetic core. If one or more magnetic field sources are multiple magnetic field sources, each flux generator can be provided by stacking multiple air-core electromagnets to provide a common air core common to all air-core electromagnets. The air core / common air core can house each electrochemical cell, e.g., a cylindrical cell.

[0031] At least one of the multiple flux generators may be a curved flux generator. Each curved flux generator may be curved to at least partially surround one of the multiple electrochemical cells. That is, each curved flux generator may be shaped and sized to at least partially bend around a curved portion of an electrochemical cell, such as a cylindrical cell. For example, each curved flux generator may include at least one curved portion (i.e., a bend) shaped and sized to bend around a curved portion of an electrochemical cell, and may also include at least a flat portion.

[0032] If each curved flux generator includes multiple magnetic field sources, these sources can be arranged around a curved, arc-shaped, circular, or polygonal section to provide the curved section of the flux generator. The curved, arc-shaped, circular, or polygonal section may be provided by a curved, semicircular, circular, or polygonal mechanical support, respectively.

[0033] Alternatively, if each flux generator includes multiple magnetic field sources, these sources may be arranged in a common plane. A flux generator containing multiple magnetic field sources arranged in a common plane is called a flat flux generator. A flat flux generator may be supplied by a single magnetic field source, which is a flat permanent magnet.

[0034] At least some of the multiple flux generators can be flat flux generators. If the apparatus comprises one or more cell stations, at least some of the flux generators may be located outside the cell station(s) (e.g., outside the cell container(s)). Additionally or alternatively, at least some of the flux generators may be located inside the cell station(s), for example, as discussed in more detail above. Conveniently, if some flux generators are located outside the cell station(s) and some are located inside the cell station(s), it can be ensured that the cell station(s) are uniformly permeated by the changing magnetic field being generated.

[0035] In some examples, the apparatus comprises one or more cell stations as discussed above, one or more flat flux generators located outside the cell station(s), and one or more flux generators located inside the cell station(s). For example, if each cell station includes a cell container, each flat flux generator may be in contact with each wall of the cell container, or each flat flux generator may be adjacent to each wall of the cell container, extending along a plane substantially parallel to the walls of the cell container and at a close distance from the walls of the cell container. Each flux generator located inside the cell station may include, for example, a single electromagnet.

[0036] As already mentioned above, the apparatus may further include a controller configured to control the changing magnetic fields generated by multiple flux generators. For example, the controller may be configured to control (e.g., change over time) the direction and / or magnitude and / or frequency of the changing magnetic fields being generated. The controller may be configured to control each changing magnetic field (e.g., by selecting values ​​for one or more of the three spatial dimensions and / or the magnitude and / or phase and / or amplitude and / or frequency of each changing magnetic field) based on one or more of the electrical, magnetic, optical, and / or acoustic measurements performed in one or more of the electrochemical cells. The electrical, magnetic, optical, and / or acoustic measurements may be performed as each changing magnetic field changes in an individually controllable manner. The apparatus may also include a sensor unit configured to perform the electrical, magnetic, optical, and / or acoustic measurements. For example, the sensor unit may include one or any combination of Hall sensors, Gaussian sensors, optical sensors, and / or acoustic sensors. The controller may be communicatively connected to the sensor unit.

[0037] The controller is As each of the multiple changing magnetic fields changes, monitor the electrochemical overpotential of each of the multiple electrochemical cells, To minimize each electrochemical overpotential, the optimal value must be selected for each changing magnetic field. It may be configured to do so.

[0038] Monitoring can be discontinuous or continuous. Alternatively, the controller can select the optimal value for any one or any combination thereof of the polarity, magnitude, phase, amplitude, and / or frequency of each changing magnetic field to minimize the electrochemical overvoltage. The controller can repeat the monitoring and selection of the optimal value for each electrochemical overvoltage as many times as necessary to minimize each electrochemical overvoltage.

[0039] The controller may be configured to monitor each electrochemical overvoltage by direct overvoltage measurement. Direct overvoltage measurement may be performed, for example, using electrochemical impedance spectroscopy (using multiple frequencies (spectroscopy) or electrical impedance measurement at a constant frequency). Alternatively, to monitor electrochemical overvoltages, one or any combination thereof of the amplitude, phase shift, and frequency of its / each cell's electrochemical potential or current may be measured.

[0040] The controller may be configured to monitor each electrochemical overvoltage using one or any combination of electrical, magnetic, optical, and acoustic measurements performed in multiple electrochemical cells. For example, such measurements may be used as proxies to determine the electrochemical overvoltage of each electrochemical cell. The controller may be electrically connected to each of the flux generators and each of the electrochemical cells.

[0041] If the controller is configured to monitor each electrochemical overvoltage using one or any combination thereof of electrical, magnetic, optical, and acoustic measurements performed in multiple electrochemical cells, the controller may be electrically connected to each flux generator and each electrochemical cell, and further communicated to a sensor unit configured to perform electrical, magnetic, optical, and / or acoustic measurements. For example, the sensor unit may include one or any combination thereof of a Hall sensor, a Gauss sensor, an optical sensor, and / or an acoustic sensor. This is because electrical, magnetic, optical, and acoustic measurements can indicate the charge / health state of the electrochemical cell. For example, an optical sensor may be configured to measure material deformation and / or accumulation / loss at selected locations in the electrochemical cell. An acoustic sensor may be configured to measure the decibel response to an acoustic signal transmitted to / reflected from one or more selected locations in the electrochemical cell. Conveniently, the decibel response can be associated with the charge state at selected locations in the electrochemical cell.

[0042] In a second aspect, the present invention relates to a method for homogenizing one or more regions within a plurality of electrochemical cells, The process involves preparing multiple magnetic flux generators, A process of arranging multiple magnetic flux generators and multiple electrochemical cells alternately, A step of generating a changing magnetic field through at least one of a plurality of electrochemical cells using one or more magnetic flux generators. This provides a method that includes [something].

[0043] In a third aspect, the present invention relates to an apparatus for homogenizing one or more regions within a plurality of electrochemical cells, It comprises multiple magnetic flux generators, each configured to generate its own magnetic field passing through at least one of multiple electrochemical cells, The apparatus provides a configuration in which multiple magnetic flux generators and multiple electrochemical cells are arranged alternately.

[0044] Next, embodiments and experiments illustrating the principle of the present invention will be discussed with reference to the attached drawings. [Brief explanation of the drawing]

[0045] [Figure 1A] This diagram schematically shows a cell station containing multiple electrochemical cells arranged inside a container. [Figure 1B] This diagram schematically shows a cell station containing multiple electrochemical cells arranged inside a container. [Figure 1C] This diagram schematically shows a cell station containing multiple electrochemical cells arranged in a tray. [Figure 1D] This diagram schematically shows a cell station containing multiple electrochemical cells arranged in a tray. [Figure 2] This figure shows a modified form of a cell station including multiple electrochemical cells and multiple magnetic flux generators. [Figure 3] This figure shows a modified form of a cell station including multiple electrochemical cells and multiple magnetic flux generators. [Figure 4] This figure shows a modified form of a cell station including multiple electrochemical cells and multiple magnetic flux generators. [Figure 5] This figure shows a modified form of a cell station including multiple electrochemical cells and multiple magnetic flux generators. [Figure 6] This figure shows a modified form of a cell station including multiple electrochemical cells and multiple magnetic flux generators. [Figure 7] This figure shows a modified form of a cell station including multiple electrochemical cells and multiple magnetic flux generators. [Figure 8A] This diagram shows multiple cell stations, as shown in Figure 2, arranged inside the tower. [Figure 8B] This figure shows multiple towers of the type shown in Figure 8A. [Figure 9A]This diagram shows multiple cell stations arranged inside the tower, as shown in Figure 3. [Figure 9B] This figure shows multiple towers of the type shown in Figure 9A. [Figure 10A] This diagram shows multiple cell stations, as shown in Figure 5, arranged inside the tower. [Figure 10B] This figure shows multiple towers of the type shown in Figure 10A. [Figure 11] This figure shows a container containing multiple cell stations interposed between multiple magnetic flux generators. [Figure 12] This is a partial view of the container shown in Figure 11. [Figure 13] This figure shows a container containing multiple cell stations interposed between multiple magnetic flux generators. [Figure 14] This is a partial view of the container shown in Figure 13. [Figure 15A] This figure shows the deformed form of a container containing multiple cell stations, sandwiched between a pair of magnetic flux generators. [Figure 15B] This figure shows the deformed form of a container containing multiple cell stations, sandwiched between a pair of magnetic flux generators. [Figure 16A] This diagram schematically shows a modified configuration of an electrochemical cell connected to a power source and a magnetic flux generator connected to a power supply unit. [Figure 16B] This diagram schematically shows a modified configuration of an electrochemical cell connected to a power source and a magnetic flux generator connected to a power supply unit. [Figure 17A] This is a schematic diagram of a device for homogenizing one or more regions within multiple electrochemical cells. [Figure 17B] Figure 17A is a partially exploded view of the apparatus. [Figure 18A] This is a schematic diagram of a device for homogenizing one or more regions within multiple electrochemical cells. [Figure 18B] Figure 18A is a partially exploded view of the apparatus. [Figure 19] This is a schematic diagram showing an electrochemical cell connected to an electrical circuit. [Figure 20A] This figure shows the current collector and electrodes of the electrochemical cell shown in Figure 19 before the deposition of the interfacial layer. [Figure 20B] This figure shows the current collector and electrodes of the electrochemical cell shown in Figure 19 after the deposition of the interfacial layer. [Figure 21A] This figure schematically shows the electrode particles of the electrode in Figure 20A before the deposition of the interface layer. [Figure 21B] This figure schematically shows the electrode particles of the electrode in Figure 20B after the deposition of the interfacial layer. [Figure 22] This diagram schematically shows the deformation form of an electrochemical cell connected to an electrical circuit. [Figure 23A] This figure shows the current collector and electrodes of the electrochemical cell shown in Figure 22 before the deposition of the interfacial layer. [Figure 23B] This figure shows the current collector and electrodes of the electrochemical cell shown in Figure 22 after the deposition of the interfacial layer. [Figure 24] This diagram schematically shows the deformation form of an electrochemical cell connected to an electrical circuit. [Figure 25A] This figure shows the current collector and electrodes of the electrochemical cell shown in Figure 24 before the deposition of the interfacial layer. [Figure 25B] This figure shows the current collector and electrodes of the electrochemical cell shown in Figure 24 after the deposition of the interfacial layer. [Figure 26] This diagram schematically shows the configuration including the electrochemical cell and magnetic flux generator. [Figure 27A] This figure schematically shows the current collector and electrodes of the electrochemical cell shown in Figure 26 before the deposition of the interfacial layer. [Figure 27B] This figure schematically shows the current collector and electrodes of the electrochemical cell shown in Figure 26 after the deposition of the interfacial layer. [Figure 28A] This figure schematically shows the electrode particles of the electrode in Figure 27A before the deposition of the interface layer. [Figure 28B] This figure schematically shows the electrode particles of the electrode in Figure 27B after the deposition of the interfacial layer. [Figure 29] This diagram schematically shows the configuration including the electrochemical cell and magnetic flux generator. [Figure 30A]This diagram schematically shows the current collector and electrodes of the electrochemical cell shown in Figure 29 before the deposition of the interfacial layer. [Figure 30B] This figure schematically shows the current collector and electrodes of the electrochemical cell shown in Figure 29 after the deposition of the interfacial layer. [Figure 31] This diagram schematically shows the configuration including the electrochemical cell and magnetic flux generator. [Figure 32A] This figure schematically shows the current collector and electrodes of the electrochemical cell shown in Figure 31 before the deposition of the interfacial layer. [Figure 32B] This figure schematically shows the current collector and electrodes of the electrochemical cell shown in Figure 31 after the deposition of the interfacial layer. [Modes for carrying out the invention]

[0046] Next, aspects and embodiments of the present invention will be discussed with reference to the accompanying drawings. Further aspects and embodiments will be apparent to those skilled in the art. Specifically, it will be apparent to those skilled in the art that other orientations of the features shown in the figures are possible. The figures are schematic and not necessarily to scale.

[0047] The present invention provides an apparatus for homogenizing one or more regions within a plurality of electrochemical cells. The apparatus comprises a plurality of flux generators, each configured to generate a magnetic field (e.g., a changing magnetic field) passing through at least one of the plurality of electrochemical cells, and the plurality of flux generators and the plurality of electrochemical cells are arranged alternately.

[0048] In general, the device can be used to homogenize one or more regions within multiple electrochemical cells and to improve cell performance during cell formation (e.g., during FA&T) and / or cell operation. Specifically, when the device is used during cell formation, it can be used in the context of large-scale manufacturing facilities such as gigafactories to form a large number of electrochemical cells under magnetoelectrochemical conditions. When the device is used during cell operation, it can be used to improve the performance of systems such as large-scale stationary equipment / stationary home energy storage.

[0049] Regardless of its intended use, the device 100 can be configured in various ways. These examples are described below with reference to Figures 1 to 17.

[0050] Firstly, the apparatus 100 may comprise one or more cell stations 12, each configured to house a plurality of electrochemical cells 20. Examples of such cell stations 12 are shown in Figures 1A to 1D. Specifically, Figures 1A and 1B show a plurality of electrochemical cells 20 housed in a cell container 15, while Figures 1C and 1D show a plurality of electrochemical cells housed in a cell tray 14. For example, each cell tray / cell container may be formed from a magnetosensitive material(s) to guide the magnetic field towards a preferred location, for example, to induce a magnetic field structure, thereby maximizing control over the magnetic field structure and minimizing stray magnetic field losses to the local environment.

[0051] For example, multiple flux generators 10 of the apparatus 100 may be arranged inside each cell station 12 such that each cell station contains at least one of the multiple flux generators 10. Specifically, Figure 2 shows a cell station 12 that includes a cell container 15 surrounding a single flat flux generator 10, the flux generator supporting multiple cylindrical electrochemical cells 20 placed upright in the flux generator.

[0052] In the examples shown in Figures 3 to 7, each cell station 12 includes a cell container 15 that encloses an electrochemical cell 20 and at least the same number of flux generators 10. In some of these arrangements, each cell 20 is sandwiched between its respective pair of flux generators 10. For example, in Figure 3, the electrochemical cell 20 is a pouch cell with multiple flat flux generators 10 alternately arranged inside the cell container 15. In the variant shown in Figure 4, the flux generators 10 are elongated slabs extending along the respective upper and lower edges of each pouch cell 20. The upper edge of the pouch cell is the edge containing the pouch cell's tab, and the lower edge is on the opposite side of the upper edge. Each pouch cell 20 is sandwiched between its respective pair of flux generators, which are positioned at the upper and lower edges of the pouch cell, respectively. Modifications to this configuration are possible. For example, the elongated magnetic flux generator 10 can extend approximately perpendicularly or at an acute / obtuse angle to the upper / lower edge of the pouch cell.

[0053] Further exemplary arrangements of the cylindrical electrochemical cells 20 are discussed with reference to Figures 5 to 7. In the example of Figure 5, each cell station 12 includes a mechanical support 51 that upright supports a plurality of flux generators 10, each of which is an air-core electromagnet extending longitudinally (i.e., axially) and radially to define the space for housing each of the plurality of cylindrical electrochemical cells 20. An air-core electromagnet here means a coil of wire (i.e., a solenoid) which includes an air-filled central space defined by the coil and does not include a solid core such as a ferromagnetic core. In this arrangement, the air-core electromagnets are uprightly supported on the floor of the cell container 15, each surrounding its respective cylindrical cell 20.

[0054] In the alternative arrangement shown in Figure 6, the cylindrical cells 20 are similarly arranged in a grid, but each flux generator 10 is a flat flux generator. The flux generators 10 are positioned such that each row of electrochemical cells 20 is sandwiched from the side between pairs of flux generators 10 that extend perpendicularly and parallel to each side wall of the cell container 15.

[0055] Finally, in the arrangement shown in Figure 7, each flux generator 10 is a disc-shaped flux generator. The cylindrical cells 20 are arranged upright in a grid pattern inside the cell container 15. Each cylindrical cell has a bottom wall, a top wall, and a side wall extending between the bottom wall and the top wall. Each flux generator 10 is located on or very close to the bottom and top walls of each cylindrical cell, so that each cell is sandwiched longitudinally (vertically) between each pair of disc-shaped flux generators 10. Each flux generator 10 may have an area equal to or approximately equal to the area of ​​the wall (i.e., the top wall or the bottom wall) on which each flux generator 10 is located or very close to.

[0056] The type of cell station 12 discussed with reference to Figures 2 to 7 can be arranged in a grid / array and / or stacked so that the cell stations 12 are aligned vertically. Conveniently, this can allow the cell stations 12 to be shelfed within a tower 17, as shown in Figures 8A to 10B, for use, for example, in large-scale cell manufacturing facilities or stationary home energy storage.

[0057] Specifically, Figures 8A, 9A, and 10A show the cell stations of Figures 2, 3, and 5, respectively, which are arranged on shelves 27 and stacked vertically within towers 17. In large-scale cell manufacturing facilities or stationary home energy storage, multiple towers 17 may be arranged adjacent to each other and / or vertically (as shown in Figures 8B, 9B, and 10B).

[0058] Next, if the device 100 comprises multiple cell stations 12, these multiple cell stations 12 may be housed (enclosed) within a container 40. This will be discussed with reference to Figures 11, 13, 15A, and 15B. In the examples of Figures 11 and 12, the container 40 includes multiple cell stations 12 (only one of which is shown) and multiple flat flux generators 10. The cell stations 12 and flux generators 10 within the container are arranged alternately. In the example of Figure 11, the flux generators 10 extend longitudinally (i.e., parallel to the side walls of the container) so that each cell station 12 is sandwiched laterally between its respective pair of flux generators 10. This is also shown in Figure 12, which is a partial view of the container 40 in Figure 11. In the example of Figure 13, the flux generators 10 extend parallel to the upper and lower walls of the container so that each cell station 12 is sandwiched longitudinally between its respective pair of flux generators 10. This is also shown in Figure 14, which is a partial view of container 40 in Figure 13.

[0059] It is also possible to position at least one of the multiple flux generators 10 outside the container 40 and adjacent to the walls of the container 40. Two such exemplary configurations will be discussed with reference to Figures 15A and 15B. In Figure 15A, the container 40 is sandwiched from the sides by a pair of flux generators 10 extending longitudinally and parallel to each side wall of the container. In the example of Figure 15B, the container 40 is sandwiched longitudinally by a pair of flux generators 10 parallel to the upper and lower walls of the container.

[0060] The apparatus 100 may include at least one power supply 1 configured to supply power to a plurality of electrochemical cells 20. For example, power supply 1 can be electrically connected to each electrochemical cell 20 via an electrical circuit 24 to supply power to each electrochemical cell 20, as shown in the schematic diagrams of Figures 16A and 16B. The schematic simplified electrochemical cell 20 shown in Figures 16A and 16B includes a pair of current collectors 22 providing each electrode 21, each having an inside coated with an active material coating, an electrolyte (not shown) provided between the electrodes, and a separator 25 provided in the electrolyte and inserted between the electrodes. It may be preferable to coat the inside of each of both current collectors with the active material coating. Generally, the active material coating can be on one side (e.g., coating only on the inside of each current collector) or on both sides (i.e., coating on both the inside and outside of each current collector). However, for visual simplicity, the active material coating on one side is shown in Figures 16A, 16B, 19, 22, 26, and 29. Each flux generator 10 is connected to a shared or individual power supply unit 2 via an electrical circuit 24' and can receive power from the shared or individual power supply unit 2. The power supply unit 2 is different from the power source 1.

[0061] In the example in Figure 15A, the flux generator 10 includes a permanent magnet 10' and a mechanism 26 for moving the permanent magnet to generate a changing magnetic field. The mechanism 26 can be, for example, an electric motor connected to the power supply unit 2 via an electrical circuit 24'. In the example in Figure 15B, the flux generator 10 includes an electromagnet, which itself is connected to the power supply unit 2 via an electrical circuit 24' to generate its respective (e.g., changing) magnetic field. The electromagnet can be any type of electromagnet. An electromagnet generally includes a coil of wire wound around a core. For example, the core can be a metal core (e.g., a ferromagnetic core) or an air-filled space in the center of the electromagnet, i.e., an air core. The magnetic field generated by the electromagnet can be changed / controlled by changing the amount and / or direction of the current supplied to the electromagnet by the power supply unit.

[0062] An exemplary configuration of a device 100 comprising multiple cell stations 12 and multiple flux generators 10, in which electrochemical cells are electrically connected to a power source 1 and flux generators are electrically connected to a shared power supply unit 2, is discussed with reference to Figures 17A and 18A. In both figures, one of the cell stations 12 is shown housing multiple electrochemical cells 20 and multiple flux generators 10, and the multiple cell stations 12 are arranged in a grid. The flux generators 10 of all cell stations 12 are electrically connected to a shared power supply unit 2, which is different from the power source 1. In the example in Figures 17A and 18A, the flux generators 10 of each row of cell station 12 are connected to the shared power supply unit 2 via their respective shared electrical connections, which are part of an electrical circuit 24'. The electrochemical cells 20 shown in Figures 17A and 18A are each connected to the power source 1, as shown in more detail in the exploded views of Figures 17B and 18B, respectively. In Figure 17A, the cells 20 and magnetic flux generators 10 within each cell station 12 are arranged in the manner shown in Figure 3, whereas in Figure 18A, the cells 20 and magnetic flux generators 10 within each cell station 12 are arranged in the manner shown in Figure 6. However, it is also possible to configure the apparatus 100 in Figures 17A and 18A such that the electrochemical cells 20 and magnetic flux generators 10 are arranged within the cell station according to any one of the cell station configurations in Figures 2, 4, 5, or 7.

[0063] Next, the advantageous effects of the present invention will be discussed with reference to Figures 18 to 32B. Specifically, exemplary configurations of an electrochemical cell 20 connected to a power supply 1 via an electrical circuit 24, for example during cell formation (e.g., during the FA&T stage) or during cell operation, are shown in Figures 19, 22, and 24. Thus, in these configurations, layers (e.g., interface layers) are formed under electrochemical conditions.

[0064] Figure 19 shows the same electrochemical cell 20 as shown in Figures 16A and 16B. Figures 22 and 24 show variations of the electrochemical cell 20 of Figure 1. The electrochemical cell of Figure 22 includes a pair of current collectors 22, 22', where only one of the current collectors 22' includes an active material coating that provides an electrode 21. The electrode 22 in Figure 19 and the active material coatings providing each electrode 22' in Figure 22 each have a textured surface. The textured surface of the active coating is provided by a plurality of spaced electrode particles. In the example of Figure 19, the electrode particles are substantially spherical, whereas in the example of Figure 22, the electrode particles are substantially rectangular and extend away from the current collector to form a columnar electrode structure. The electrochemical cell 20 of Figure 24 includes only a pair of flat current collectors 22 that act as electrodes and does not include an active material coating. Generally, electrodes can be provided by a current collector containing nothing (i.e., without an active material coating), by a single-layer or multi-layer stack of an active material coating, or by filling with an active (electrode) material.

[0065] During cell formation and / or operation under electrochemical conditions, each layer (such as an interface layer) 23 is formed on the electrode 21. For example, the interface layer 23 can be part of the solid electrolyte interface (SEI). The formation of the interface layer 23 in the example cells 20 in Figures 19, 22, and 24 is shown in Figures 20A and 20B, 23A and 23B, and 25A and 25B, respectively. Specifically, Figures 20A, 23A, and 25A show exploded views of the respective cells 20 in Figures 19, 22, and 24, including one of its electrodes 21, before the formation of the interface layer. As already discussed, it can be difficult to reliably control the formation of layers under electrochemical conditions. Therefore, the interface layers 23 formed under these conditions usually have a heterogeneous structure, and this heterogeneous structure can adversely affect the performance of the electrochemical cell 20.

[0066] The formed interface layers 23 are shown in Figures 20B, 23B, and 25B, respectively. As can be seen from these figures, each interface layer 23 is non-homogeneous and not uniformly distributed on the electrode 21. In fact, this is also shown in Figures 21A and 21B, where Figure 21A shows a partially exploded view of the electrode of Figure 20A (i.e., a single electrode particle) before the formation of the interface layers 23, while Figure 21B shows the electrode particle of Figure 21A coated with a portion of the non-homogeneous interface layer 23.

[0067] The lack of homogeneity in the interface layer 23 is one example of a technical problem addressed by the present invention.

[0068] The present invention is based on the observation that providing a magnetic field through an electrochemical cell while the cell is under electrochemical conditions (during cell formation and / or cell operation) improves the performance and / or lifespan of the cell by significantly increasing the homogeneity of the formed layer, and therefore one or more regions within the cell.

[0069] This concept is illustrated in Figures 26 to 32B. Specifically, Figures 26, 29, and 31 show the electrochemical cells 20 in Figures 19, 22, and 24, respectively, connected to a power source 1 via an electrical circuit 24, and further, a magnetic flux generator 10 configured to generate a magnetic field (e.g., a changing magnetic field) passing through the electrochemical cell 20. Thus, the cells in Figures 26, 29, and 31 are exposed to magnetoelectrochemical conditions by providing a magnetic field through the cell. This enhances the homogeneity of the deposited interface layer 23, as shown in Figures 27A, 27B, 28A, 28B, 30A, 30B, 32A, and 32B, in contrast to Figures 20A, 20B, 21A, 21B, 23A, 23B, 25A, and 25B, respectively.

[0070] The apparatus 100 is modifiable. Each magnetic field generated by each flux generator 10 can be a static or a changing magnetic field. Each changing magnetic field can be a rotating magnetic field, a pulsed magnetic field, and / or an oscillating magnetic field, or any combination thereof. The rotation of each changing magnetic field can be around an axis having a component perpendicular to the direction of each changing magnetic field. The rotation of each changing magnetic field can be around an axis having a component parallel to the direction of each changing magnetic field. The rotation of each changing magnetic field can be around an axis having a component perpendicular to the direction of current flow in its / each electrochemical cell. The rotation of each changing magnetic field can be around an axis having a component parallel to the direction of current flow in its / each electrochemical cell. Each rotating magnetic field can be provided by rotating one or more of the electrochemical cells with a rotating permanent magnet, or temporary magnet, or electromagnet, or by an array of electromagnets acting sequentially to effectively rotate each magnetic field.

[0071] Each changing magnetic field can be controllably varied in one, two, and / or three spatial dimensions. Additionally or alternatively, the polarity and / or magnitude of each magnetic field can be controllably varied.

[0072] Each flux generator may include one or more magnetic field sources. These one or more sources may be multiple magnetic field sources. These multiple sources may be arranged in a common plane. At least one of the one or more magnetic field sources may include a permanent magnet and a mechanism (e.g., an electric motor) for moving one or more of the permanent magnet and / or electrochemical cells. At least one of the one or more magnetic field sources may be an electromagnet.

[0073] For example, the apparatus 100 shown in Figures 17A and 18A may further include a controller (not shown) configured to monitor the electrochemical overvoltage of one or more electrochemical cells 20 as each of one or more changing magnetic fields changes, and to select an optimal value for each changing magnetic field to minimize each electrochemical overvoltage. The monitoring may be discontinuous or continuous. Furthermore, the controller may minimize the electrochemical overvoltage by selecting an optimal value for any one or any combination thereof of the polarity, magnitude, phase, amplitude, and / or frequency of each changing magnetic field. The controller may repeat the monitoring of each electrochemical overvoltage and the selection of the optimal value as many times as necessary to minimize each electrochemical overvoltage.

[0074] The controller may be configured to monitor each electrochemical overvoltage by direct overvoltage measurement. Direct overvoltage measurement may be performed, for example, using electrochemical impedance spectroscopy (using electrical impedance measurements at multiple frequencies or a constant frequency impedance). Alternatively, to monitor electrochemical overvoltages, one or any combination of the amplitude, phase shift, and frequency of its / each cell's electrochemical potential or current may be measured.

[0075] The controller may be configured to monitor each electrochemical overvoltage using one or any combination thereof of electrical, magnetic, optical, and acoustic measurements performed in one or more electrochemical cells. For example, such measurements may be used as proxies for determining the electrochemical overvoltage of each electrochemical cell. The controller may be electrically connected to each of the one or more flux generators and to each of the one or more electrochemical cells.

[0076] If the controller is configured to monitor each electrochemical overvoltage using one or any combination thereof of electrical, magnetic, optical, and acoustic measurements performed in one or more electrochemical cells, the controller may be electrically connected to each flux generator and each electrochemical cell, and may also be communicatively connected to a sensor unit (not shown) configured to perform electrical, magnetic, optical, and / or acoustic measurements. For example, the sensor unit may include one or any combination thereof of a Hall sensor, a Gauss sensor, an optical sensor, and / or an acoustic sensor. This is because electrical, magnetic, optical, and acoustic measurements can indicate the charge / health state of the electrochemical cells. For example, an optical sensor may be configured to measure material deformation and / or accumulation / loss at selected locations in one or more electrochemical cells. An acoustic sensor may be configured to measure the decibel response to an acoustic signal transmitted to / reflected from one or more selected locations in one or more electrochemical cells. An exemplary sensor configuration is shown in Figure 11 of UK Patent Application No. 2301222.2, which subject matter is incorporated herein by reference.

[0077] Features disclosed in the above description, or in the following claims, or in the accompanying drawings, in particular in those forms, or with respect to means for performing the disclosed functions or methods or processes for obtaining the disclosed results, may be used, as necessary, separately or in any combination of such features to implement the present invention in various forms.

[0078] While the present invention has been described in conjunction with the exemplary embodiments described above, many equivalent modifications and variations will become apparent to those skilled in the art upon being given this disclosure. Therefore, the exemplary embodiments of the present invention described above are considered illustrative and not limiting. Various modifications to the described embodiments can be made without departing from the spirit and scope of the invention.

[0079] To avoid any doubts, any theoretical explanations provided herein are provided solely to enhance the reader's understanding. The inventors do not wish to be bound by any of these theoretical explanations.

[0080] Any section headings used in this specification are for structural purposes only and should not be construed as limiting the subject matter described.

[0081] Throughout this Specification, including the claims that follow, unless the context requires otherwise, the words “comprise” and “include,” as well as variations such as “comprises,” “comprising,” and “including,” are understood to imply that they include the integer or process or group of integers or processes mentioned, but not to imply that they exclude any other integer or process or group of integers or processes.

[0082] When used herein and in the appended claims, the singular forms “a,” “an,” and “the” refer to multiple objects unless the context explicitly indicates otherwise. Ranges may be expressed herein as “about” one particular value and / or “about” another particular value. Where such ranges are expressed, another embodiment includes the above one particular value and / or the above another particular value. Similarly, the use of the antecedent “about” means that when a value is expressed as an approximation, that particular value forms another embodiment. The term “about” in relation to numbers is optional and means, for example, + / - 10%.

Claims

1. An apparatus for homogenizing one or more regions within multiple electrochemical cells, The system comprises a plurality of magnetic flux generators, each configured to generate a variable magnetic field that passes through at least one of the plurality of electrochemical cells, The apparatus is configured such that the plurality of magnetic flux generators and the plurality of electrochemical cells are arranged alternately.

2. The apparatus according to claim 1, comprising one or more cell stations, each configured to house the respective plurality of electrochemical cells.

3. The apparatus according to claim 2, wherein the plurality of flux generators are arranged inside each cell station such that each cell station includes at least one of the plurality of flux generators.

4. The apparatus according to claim 3, wherein each cell station includes at least the same number of magnetic flux generators as the electrochemical cells.

5. The apparatus according to claim 4, wherein the magnetic flux generators and electrochemical cells in each of the cell stations are arranged alternately.

6. The apparatus according to any one of claims 2 to 4, wherein the one or more cell stations are a plurality of cell stations.

7. The apparatus according to claim 6, wherein the plurality of magnetic flux generators are interposed between the plurality of cell stations.

8. The apparatus according to claim 7, wherein the magnetic flux generator and the cell station are arranged such that each cell station is sandwiched between each pair of the plurality of magnetic flux generators.

9. The apparatus according to any one of claims 3 to 8, wherein the plurality of cell stations are housed inside a container having one or more walls, and at least one of the plurality of magnetic flux generators is located outside the container, adjacent to each of the one or more walls of the container.

10. The apparatus according to any one of claims 1 to 9, further comprising at least one power supply configured to supply power to the plurality of electrochemical cells.

11. The apparatus according to claim 10, dependent on claim 6, wherein the at least one power supply is a plurality of power supplies, each configured to supply power to the electrochemical cells in each of the plurality of cell stations.

12. The apparatus according to claim 10 or 11, wherein the at least one power source is further configured to supply power to the plurality of magnetic flux generators.

13. The apparatus according to any one of claims 10 to 12, wherein each flux generator is connected to a shared or individual power supply unit and receives power from the shared or individual power supply unit, and the shared or individual power supply unit is different from the at least one power source.

14. The apparatus according to claim 13, wherein, when each magnetic flux generator is connected to the shared power supply unit, a subset of the plurality of magnetic flux generators is each connected to the shared power supply unit via its respective shared electrical connection.

15. The apparatus according to any one of claims 1 to 14, wherein each changing magnetic field is one of a rotating magnetic field, a pulsed magnetic field, and / or an oscillating magnetic field, or any combination thereof.

16. The apparatus according to any one of claims 1 to 15, wherein each changing magnetic field is controllably variable in one, two, or three spatial dimensions.

17. The apparatus according to any one of claims 1 to 16, wherein each magnetic flux generator includes one or more magnetic field sources.

18. The apparatus according to claim 17, wherein at least one of the one or more magnetic field sources includes a permanent magnet and a mechanism for moving the permanent magnet and / or one or more of the electrochemical cells.

19. The apparatus according to claim 17, wherein at least one of the one or more magnetic field sources is an electromagnet.

20. The apparatus according to claim 19, wherein each electromagnet is an air-core electromagnet extending longitudinally to define a space for housing each of the one or more electrochemical cells.

21. The apparatus according to any one of claims 17 to 20, wherein the one or more magnetic field sources are a plurality of magnetic field sources.

22. The apparatus according to claim 21, wherein the plurality of magnetic field sources are arranged in a common plane.

23. As each of the aforementioned multiple changing magnetic fields changes, the electrochemical overvoltage of each of the aforementioned multiple electrochemical cells is monitored, To minimize each electrochemical overpotential, the optimal value must be selected for each changing magnetic field. The apparatus according to any one of claims 1 to 22, further comprising a controller configured to do the following.

24. A method for homogenizing one or more regions within multiple electrochemical cells, The process involves preparing multiple magnetic flux generators, The process of arranging the plurality of magnetic flux generators and the plurality of electrochemical cells alternately, A step of generating each changing magnetic field passing through at least one of the plurality of electrochemical cells using one or more of the magnetic flux generators. Methods that include...

25. An apparatus for homogenizing one or more regions within multiple electrochemical cells, The system comprises a plurality of magnetic flux generators, each configured to generate a magnetic field that passes through at least one of the plurality of electrochemical cells, The plurality of magnetic flux generators and the plurality of electrochemical cells are arranged alternately. Device.

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