Battery pack and energy storage cabinet

Abstract

The utility model provides a battery pack and an energy storage cabinet. The battery pack may include at least two sets of first coils arranged in a first direction. Each group of first coils comprises at least one first coil. A first battery cell is arranged between any two adjacent groups of first coils, and the two groups of first coils are symmetrically arranged relative to the first battery cell. The two groups of coils are used for applying a constant magnetic field to the first battery cell when current is introduced, so that the constant magnetic field is applied to the first battery cell in the battery pack. Therefore, the electrode material in the first battery cell is magnetized by the constant magnetic field, so that ions in the first battery cell are magnetically arranged and flow and diffusion of the ions are accelerated, thereby reducing polarization internal resistance in the first battery cell and improving electrochemical reaction speed. Therefore, the capacity, the fast charging capacity and the energy efficiency of the first battery cell can be improved, and the service life of the first battery cell is prolonged.

Description

Technical Field

[0001] This application relates to the field of energy storage technology, and in particular to a battery pack and an energy storage cabinet. Background Technology

[0002] Lithium-ion batteries are widely used in new energy vehicles, energy storage, and other fields due to their high energy density and long lifespan. In practical applications, multiple cells are typically integrated into a battery pack through series or parallel connections. However, individual differences exist among the cells. Under the control of the battery management unit (BMU), the battery pack stops discharging when the voltage of a single cell reaches the discharge cutoff voltage, and stops charging when the voltage of a single cell reaches the charging cutoff voltage. Therefore, the lowest capacity cell in the battery pack significantly affects the overall capacity utilization of the pack. Utility Model Content

[0003] This application provides a battery pack and energy storage cabinet, which improves the capacity and energy efficiency of the battery cells by applying a constant magnetic field to the battery cells, thereby improving the overall performance of the battery pack.

[0004] In a first aspect, this application provides a battery pack. Specifically, the battery pack includes at least two sets of first coils arranged along a first direction, each set of first coils including at least one first coil. A first battery cell is disposed between any two adjacent sets of first coils, and the two sets of first coils are symmetrically arranged with respect to the first battery cell. The two sets of first coils are used to apply a constant magnetic field to the first battery cell when current is applied.

[0005] In this application, the battery pack may include multiple battery cells. When the battery pack is in a charging or discharging state, a constant current is passed through a first coil, which applies a constant magnetic field to both sides of the first battery cell. The first battery cell may be one or more cells. Specifically, when the battery pack is charging, ions inside the cell move from the positive electrode material to the negative electrode material; when the battery pack is discharging, ions move from the negative electrode material to the positive electrode material. Taking charging as an example, when ions move near the negative electrode material, due to the presence of tiny protrusions on the surface of the negative electrode material, the ions move along the surface of these tiny protrusions and tend to preferentially deposit on the surface of these tiny protrusions, thereby triggering dendrite growth. When the first coil applies a constant magnetic field, the ions cutting through the magnetic field lines of the constant magnetic field as they move along the surface of the tiny protrusions cause the ions to move in a spiral direction due to the Lorentz force, thus preventing ion deposition near the tiny protrusions. Therefore, the electrode material inside the first cell is magnetized by a constant magnetic field, causing the ions inside the first cell to align magnetically and accelerating the flow and diffusion of ions, thereby reducing the polarization resistance inside the first cell and improving the electrochemical reaction rate. This can increase the capacity, fast charging capability and energy efficiency of the first cell, extend the lifespan of the first cell, and thus improve the overall performance of the battery pack.

[0006] In one embodiment, the battery pack may further include at least two sets of second coils arranged along a second direction, perpendicular to the first direction. Each of the aforementioned at least two sets of second coils includes at least one second coil. A second battery cell is disposed between any two adjacent sets of second coils, and the two sets of second coils are symmetrically arranged with respect to the second battery cell. The two sets of second coils are used to apply a constant magnetic field to the second battery cell when current is applied. The first battery cell and the second battery cell may be the same cell or different cells. That is, the battery cell includes four sides connected in sequence, wherein two opposite sides may be provided with two first coils, or two opposite sides may be provided with two second coils, or two opposite sides may be provided with two first coils and two opposite sides may be provided with two second coils. In this embodiment, the first coil and the second coil apply magnetic fields in two directions to the battery cell of the battery pack, respectively. Similar to the principle of the first coil applying a constant magnetic field to the first cell, the electrode material inside the second cell is also magnetized by the constant magnetic field generated by the second coil. This causes the ions inside the second cell to magnetically align and accelerates the flow and diffusion of ions, thereby reducing the polarization resistance inside the second cell and increasing the electrochemical reaction rate. This can increase the capacity, fast charging capability, and energy efficiency of the second cell, extend the lifespan of the second cell, and thus improve the overall performance of the battery pack.

[0007] In one embodiment, the at least two sets of first coils are connected in parallel, each set comprising at least two first coils arranged along a second direction and connected in series. Thus, each first coil in each set can be applied with the same current, generating the same constant magnetic field, and the current flowing through each set can be independently controlled. Similarly, the at least two sets of second coils are connected in parallel, each set comprising at least two second coils arranged along a first direction and connected in series. Thus, each second coil in each set can be applied with the same current, generating the same constant magnetic field, and the current flowing through each set can be independently controlled.

[0008] In one embodiment, a first heat insulation layer is disposed between the first battery cell and the two sets of first coils, and a second heat insulation layer is disposed between the second battery cell and the two sets of second coils. The heat insulation layer can be used to block the heat generated by the coils from being transferred to adjacent battery cells, thereby preventing thermal runaway due to excessive temperature. Simultaneously, the heat insulation layer also acts as a buffer, preventing significant suppression of the battery cell by the coils when the battery cell expands, thus preventing stress concentration within the battery cell and lithium plating. Specifically, the heat insulation layer can be heat-insulating foam.

[0009] In one embodiment, the outer surface of each of the at least two sets of first coils and each of the at least two sets of second coils is covered with an insulating layer to achieve insulation isolation between the first coil and the first battery cell, and between the second coil and the second battery cell, so as to prevent damage to the battery cell when the coil is short-circuited.

[0010] In one embodiment, a constant magnetic field can be generated in the coil by passing a constant current through it. During the charging or discharging of the battery pack, a constant current can be passed through the first coil. Similarly, a constant current can also be passed through the second coil.

[0011] In one embodiment, the battery pack may include two sets of first coils arranged along a first direction, with a plurality of first cells disposed between the two sets of first coils; and / or, the battery pack may include two sets of second coils arranged along a second direction, with a plurality of second cells disposed between the two sets of second coils. In this embodiment, the first coil sets and / or the second coil sets may apply a constant magnetic field to the outside of the plurality of cells, thereby reducing the number of coils while achieving a constant magnetic field.

[0012] In one embodiment, the first battery cell includes four side surfaces connected in sequence. Two of these side surfaces are arranged opposite each other along a first direction, and the other two side surfaces are arranged opposite each other along a second direction. The area of ​​the two side surfaces is larger than the area of ​​the other two side surfaces. In this embodiment, the two side surfaces are the two large surfaces of the first battery cell. During charging or discharging of the battery pack, ions inside the first battery cell mainly move between the positive and negative electrode materials in a direction perpendicular to the two large surfaces. Since the magnetic field direction of the constant magnetic field generated by the first coil is perpendicular to the two large surfaces, as long as the movement direction of the ions deviates from the magnetic field direction, they can cut the magnetic field lines, thereby allowing the ions inside the first battery cell to be deposited more uniformly on the surface of the positive or negative electrode materials.

[0013] In the battery pack of this application, the first coil is disposed adjacent to the large surface of the first cell. Specifically, the area of ​​the first coil can be less than or equal to the area of ​​the large surface of the first cell, so that the first coil does not increase the distance between the battery pack casing and the first cell. Alternatively, the area of ​​the first coil can also be greater than the area of ​​the large surface of the first cell, that is, the first coil can be sleeved on the outer periphery of the first cell to facilitate the positioning of the first coil. For example, in one embodiment, the area of ​​any one of the two sets of first coils covers at least 85% of any one of the two sets of side surfaces of the first cell.

[0014] In one embodiment, the battery pack may further include a first liquid cooling plate. The first liquid cooling plate is located at the bottom of the first cell and is thermally connected to each of the at least two sets of first coils. The first liquid cooling plate can dissipate heat from the first coils, thereby preventing the battery pack from overheating and causing thermal runaway.

[0015] In one embodiment, a thermally conductive adhesive with a thermal conductivity greater than or equal to 0.5 W / (mK) is disposed between the liquid cooling plate and each first coil. The thermally conductive adhesive can transfer heat from the first coil to the liquid cooling plate, thereby accelerating heat exchange between the first coil and the liquid cooling plate.

[0016] In one embodiment, the battery pack has a port to which at least two sets of first coils are connected. All the first coils within the battery pack can be pooled together and powered through the port, thereby facilitating centralized control of the first coils.

[0017] In one embodiment, the battery pack further includes a second liquid cooling plate corresponding to each group of first coils. The second liquid cooling plate has a U-shaped structure and is sandwiched between opposite sides of each group of first coils, with the second liquid cooling plate located between the first cell and each group of first coils. In this embodiment, each second liquid cooling plate can sandwich a group of first coils within the U-shaped structure, thereby increasing the heat dissipation area between the first coils and the second liquid cooling plate, and improving the heat dissipation efficiency of the first coils.

[0018] In one embodiment, a thermally conductive material may be disposed between the liquid cooling plate and the first battery cell, thereby accelerating the heat exchange between the second liquid cooling plate and the first battery cell.

[0019] Secondly, this application also provides an energy storage cabinet. The energy storage cabinet includes a rack, which houses multiple battery packs as described in the first aspect. In this energy storage cabinet, a constant magnetic field is applied to the cells of the battery packs, causing the electrode materials inside the cells to be magnetized. This causes the ions to magnetically align and accelerates the flow and diffusion of ions, thereby reducing the polarization resistance inside the cells and improving the electrochemical reaction rate. This can increase the capacity, fast charging capability, and energy efficiency of the cells, extend the lifespan of the cells, and thus improve the overall performance of the battery pack.

[0020] Thirdly, this application also provides an energy storage cabinet. The energy storage cabinet includes a cabinet that houses at least one battery pack. Corresponding to each of the aforementioned at least one battery pack, the cabinet is provided with at least one pair of coils, which are located outside each battery pack and symmetrically arranged relative to each battery pack. The at least one pair of coils are used to apply a constant magnetic field to each battery pack when current is applied. During the charging or discharging process of the battery pack, the constant magnetic field applied to the battery pack magnetizes the electrode material inside the cell, causing ions to magnetically align and accelerating ion flow and diffusion, thereby reducing the polarization resistance inside the cell and improving the electrochemical reaction rate. This can improve the cell's capacity, fast charging capability, and energy efficiency, and extend the cell's lifespan, thereby improving the overall performance of the battery pack.

[0021] The outer casing of the aforementioned battery pack is made of a material with a magnetic permeability greater than or equal to 4π × 10⁻⁶. -7 H / m, and less than or equal to 4π×10 -5 Materials with H / m. For example, the battery pack casing can be made of materials such as aluminum, copper, or plastic to reduce the magnetic conductivity of the casing, thereby reducing the casing's influence on a constant magnetic field. Attached Figure Description

[0022] Figure 1 A schematic diagram of an energy storage cabinet provided in an embodiment of this application;

[0023] Figure 2 An internal schematic diagram of an energy storage cabinet provided in an embodiment of this application;

[0024] Figure 3 Another internal schematic diagram of the energy storage cabinet provided in the embodiments of this application;

[0025] Figure 4 for Figure 3 An exploded view of the cabinet, battery pack, and coil assembly.

[0026] Figure 5A schematic diagram of a battery pack provided in an embodiment of this application;

[0027] Figure 6 for Figure 5 Another schematic diagram of the battery pack in the diagram;

[0028] Figure 7 A schematic diagram of another battery pack provided in an embodiment of this application;

[0029] Figure 8 for Figure 7 Exploded view of the battery pack in the image;

[0030] Figure 9 A schematic diagram of another battery pack provided in an embodiment of this application;

[0031] Figure 10 for Figure 9 Exploded view of the battery pack in the image;

[0032] Figure 11 This is a schematic diagram of another battery pack provided in an embodiment of this application.

[0033] Figure label:

[0034] 10-Energy Storage Cabinet 11-Rack 20-Battery Pack

[0035] 21-Outer casing 22-Battery cell 23-Insulation layer

[0036] 24-Liquid cooling plate; 25-Buffer plate; 30-Coil assembly

[0037] 31-Coil; 32-Port; 241-Heat conductor

[0038] 242 - First liquid cooling plate; 243 - Second liquid cooling plate; 244 - Thermally conductive material Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this application clearer, the application will now be described in further detail with reference to the accompanying drawings.

[0040] To facilitate understanding of the battery pack and energy storage cabinet provided in this application embodiment, their application scenarios are described below. The battery pack of this application can be used in scenarios such as home energy storage, industrial energy storage, data centers, and vehicles for storing and releasing electrical energy. Specifically, the battery pack can be applied to an energy storage system, which can be an energy storage cabinet, an energy storage container, or an uninterruptible power supply (UPS) system. In practical applications, to enable the battery pack to store more electrical energy, it typically includes multiple battery cells. However, inconsistencies in the battery cells can lead to problems such as capacity and lifespan loss, and a rapid increase in internal resistance.

[0041] To address the aforementioned inconsistencies, existing battery packs incorporate a Battery Management Unit (BMU). This BMU manages the battery pack's thermal and electrical systems during operation. Specifically, the BMU can regulate the temperature difference across the entire battery pack through its thermal management module, keeping it within a manageable range. The electrical management functions of the BMU include: during battery pack discharge, the entire battery pack stops discharging when the voltage of the lowest-capacity cell reaches the discharge cutoff voltage; during battery pack charging, the entire battery pack stops charging when the voltage of the highest-capacity cell reaches the charging cutoff voltage. Therefore, the battery pack's capacity utilization is influenced by the lowest-capacity cell.

[0042] In view of this, this application provides a battery pack and energy storage cabinet, which improves the capacity and energy efficiency of the battery cells by applying a constant magnetic field to the battery cells of the battery pack, thereby improving the overall performance of the battery pack.

[0043] It should be noted that the terminology used in the following embodiments is for the purpose of describing specific embodiments only and is not intended to be a limitation of this application. As used in the specification and appended claims of this application, the singular expressions “a,” “an,” “the,” “the,” “the,” and “this” are intended to also include expressions such as “one or more,” unless the context clearly indicates otherwise.

[0044] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0045] In this application, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "multiple" means two or more.

[0046] Furthermore, in this article, directional terms such as "top," "bottom," "upper," and "lower" are defined relative to the orientation of the structure as shown in the attached drawings. It should be understood that these directional terms are relative concepts, used for relative description and clarification, and can change accordingly depending on the orientation of the structure.

[0047] Figure 1 This is a schematic diagram of an energy storage cabinet provided in an embodiment of this application. Figure 1 As shown, the energy storage cabinet 10 includes a cabinet 11. Multiple battery packs 20 are installed inside the cabinet 11, and the multiple battery packs 20 are stacked along the height direction H of the cabinet 11. Figure 2 This is an internal schematic diagram of the energy storage cabinet provided in an embodiment of this application. Figure 3 Another internal schematic diagram of the energy storage cabinet provided in an embodiment of this application. (See attached diagram.) Figure 2 and Figure 3 As shown, in some embodiments, for each battery pack 20 within the cabinet 11, the cabinet 11 may be provided with a coil assembly 30. The coil assembly 30 is used to apply a constant magnetic field to the corresponding battery pack 20.

[0048] Figure 4 for Figure 3 An exploded view of the cabinet, battery pack, and coil assembly. (See attached diagram.) Figure 3 and Figure 4 As shown, the coil assembly 30 includes at least one pair of coils 31, each of the at least one pair of coils 31 including a centerline relative to the battery pack 20 (e.g., ...). Figure 3 Two coils 31 are symmetrically arranged (as shown by the dashed line in the diagram). The battery pack 20 includes a casing 21 and multiple battery cells 22, which are located inside the casing 21. The two coils 31 are used to apply a constant magnetic field to each battery pack 20 when a constant current is applied. Therefore, the electrode material inside the battery cells 22 in the battery pack 20 is magnetized by the constant magnetic field, causing the ions inside the battery cells 22 to magnetically align and accelerate the flow and diffusion of ions, thereby reducing the polarization resistance inside the battery cells 22, increasing the electrochemical reaction rate, and thus simultaneously increasing the actual usable capacity of the battery pack 20 and extending its service life. It should be noted that the actual usable capacity of the battery pack 20 mainly refers to the capacity that the battery pack 20 can exert during discharge.

[0049] When an external magnetic field acts on the battery pack 20, the internal cells 22 of the battery pack 20 are magnetized due to the wave-particle radiation characteristics of the magnetic field. Taking a lithium-ion battery pack as an example, during charging or discharging, the electrode material inside the cell 22 generates many tiny magnetic dipoles and unpaired electrons. Under the influence of the magnetic field, the aforementioned particulate matter undergoes magnetic alignment, which can construct a crystal structure that facilitates lithium-ion insertion or extraction, as well as crystal faces that are conducive to electrochemical reactions, thereby accelerating the flow and diffusion of lithium ions near the electrodes. In other words, the introduction of a magnetic field can reduce the polarization resistance of the cell 22, thereby increasing the electrochemical reaction rate. This increases the actual usable capacity of the battery pack 20, thus improving its fast-charging capability and energy efficiency, and extending its service life.

[0050] On the other hand, the surface of the negative electrode material is usually not perfectly flat; it contains tiny protrusions. When lithium ions move towards the negative electrode material, they tend to preferentially deposit on the protruding surfaces rather than the flat ones, resulting in an uneven distribution of lithium ion concentration on the surface of the negative electrode material. The continuous deposition of lithium ions on the protruding surfaces triggers the growth of lithium dendrites.

[0051] When the aforementioned magnetic field is introduced into the battery pack 20, lithium ions can change their direction of movement when approaching the protrusions. Specifically, lithium ions cut through magnetic field lines along the direction of movement on the protrusion surface. Under the influence of the magnetic field, lithium ions experience a Lorentz force perpendicular to both the electric and magnetic fields, causing them to move in a helical direction. This prevents lithium ions from depositing near the protrusions. Therefore, a uniform distribution of lithium ions on the electrode surface can ultimately be achieved. Thus, the magnetic field reduces the concentration gradient and concentration polarization of lithium ions, thereby suppressing dendrite growth and improving the fast-charging performance of the battery pack 20.

[0052] In the energy storage cabinet 10, each pair of coils 31 can be symmetrically arranged along a first direction A, so the coil assembly 30 can apply a constant magnetic field along the first direction A to the battery pack 20. When the coil assembly 30 includes multiple pairs of coils 31, some of the coil pairs can be symmetrically arranged along the first direction A relative to one centerline of the battery pack 20, and other coil pairs can be symmetrically arranged along a second direction B relative to another centerline of the battery pack 20, with the second direction B perpendicular to the first direction A. In this way, the coil assembly 30 can apply two constant magnetic fields in different directions (i.e., the first direction A and the second direction B) to the battery pack.

[0053] In the above embodiments, the first direction A can be any one of the height direction, length direction, or width direction of the battery pack 20.

[0054] Furthermore, the number of coils 31 can be designed according to the size of the battery pack 20. For example... Figures 2 to 4As shown, in one embodiment, the coil assembly 30 may include two pairs of coils 31. The two pairs of coils 31 are arranged side by side along a second direction B.

[0055] It should be noted that the coil 31 in this application can be a winding formed by winding the conductor in a ring or loop shape. When the thickness of the winding is ignored, the winding can be considered as a ring or loop-shaped plane. The area of ​​the coil 31 refers to the area of ​​the coil 31 projected onto this plane. For example, as... Figure 4 As shown, coil 31 is in the shape of a ring, and the area of ​​coil 31 is the area of ​​the ring pattern.

[0056] In some embodiments, the area of ​​coil 31 may be less than or equal to the area of ​​the side of battery pack 20 adjacent to coil 31. For example... Figure 4 As shown, in one embodiment, one side of the battery pack 20 perpendicular to the first direction A can be arranged adjacent to two coils 31 side by side, and the other side of the battery pack 20 perpendicular to the first direction A can be arranged adjacent to two coils 31 side by side.

[0057] In another embodiment, the battery pack 20 includes four sides connected in sequence, wherein the area of ​​two opposite sides is larger than the area of ​​the other two opposite sides. That is, these two sides constitute the large surfaces of the battery pack 20. Specifically, one large surface of the battery pack 20 is adjacent to a coil 31, and another large surface is adjacent to another coil 31. The areas of the two coils 31 can each be equal to 90% of the area of ​​the large surface, that is, the coils 31 can cover 90% of the area of ​​the large surface of the battery pack 20.

[0058] In other embodiments, the area of ​​coil 31 may also be larger than the area of ​​the side surface of battery pack 20. Therefore, coil 31 can be fitted around the outer periphery of battery pack 20. In specific applications, coil 31 can be fixed inside cabinet 11. When battery pack 20 is placed in cabinet 11, coil 31 can be fitted around the outer periphery of battery pack 20.

[0059] like Figures 2 to 4 As shown, the battery pack 20 may further include a battery management unit, which and the aforementioned plurality of battery cells 22 are located within the housing 21. The two coils 31 are symmetrically arranged on both sides of the plurality of battery cells 22 along a first direction A relative to the centerline of the battery pack 20, and the battery management unit may be located on one side of the plurality of battery cells 22 along a second direction B. Thus, the constant magnetic field generated by the coils 31 acts directly on the plurality of battery cells 22 without passing through the battery management unit.

[0060] In the aforementioned energy storage cabinet 10, the outer shell 21 of the battery pack 20 is made of a material with a magnetic permeability greater than or equal to 4π×10⁻⁶. -7 H / m, and less than or equal to 4π×10 -5Materials with H / m. For example, the outer casing 21 of the battery pack 20 can be made of materials such as aluminum, copper or plastic to reduce the magnetic conductivity of the outer casing 21, thereby reducing the influence of the outer casing 21 on the constant magnetic field.

[0061] In addition, a coil power supply may be installed inside the cabinet 11, which is electrically connected to the coil assembly 30. The coil power supply is used to provide power to the coil assembly 30 of the battery pack 20.

[0062] In this application, the coil assembly 30 can be installed not only inside the cabinet 11, but also inside the battery pack 20, so as to directly apply a constant magnetic field to the battery cells 22 inside the battery pack 20.

[0063] Figure 5 This is a schematic diagram of a battery pack provided in an embodiment of this application. Figure 6 for Figure 5 Another schematic diagram of the battery pack. (See diagram below.) Figure 5 and Figure 6 As shown, the coil assembly 30 is located within the housing 21. The coil assembly 30 includes at least two sets of coils arranged sequentially along a first direction A, each of the at least two sets of coils including at least one coil 31 arranged sequentially along a second direction B. At least one battery cell 22 is disposed between two adjacent sets of coils along the first direction A, and the two coils 31 are symmetrically arranged with respect to the at least one battery cell 22. The two coils 31 are used to apply a constant magnetic field to the at least one battery cell 22 when a constant current is applied.

[0064] In the above embodiment, the coil assembly 30 can apply a constant magnetic field to the cell 22 within the battery pack 20. At this time, the electrode material inside the cell 22 is magnetized by the constant magnetic field, causing the ions within the cell 22 to magnetically align and accelerating ion flow and diffusion. This reduces the internal polarization resistance of the cell 22, thereby increasing the electrochemical reaction rate. This improves the capacity, fast-charging capability, and energy efficiency of the cell 22, extends its lifespan, and ultimately enhances the overall performance and lifespan of the battery pack 20.

[0065] In one embodiment, the coil assembly 30 can apply a constant magnetic field to both sides of the plurality of battery cells 22. Specifically, the coil assembly 30 includes two sets of coils arranged sequentially along a first direction A, with the plurality of battery cells 22 disposed between the two sets of coils. In this way, the coil assembly 30 can apply a constant magnetic field to all the battery cells 22 of the battery pack 20 as a whole, and the coil assembly 30 is simpler and less expensive.

[0066] like Figure 5 and Figure 6As shown, in another embodiment, the coil assembly 30 can apply a constant magnetic field to both sides of a single cell 22. Specifically, each coil group can include at least two coils 31 arranged sequentially along the second direction B. A cell 22 can be disposed between two adjacent coils 31 along the first direction A. In this embodiment, the two coils 31 can be symmetrically arranged along the centerline of a single cell 22. In this way, the coil assembly 30 can apply a constant magnetic field to each cell 22 individually, thereby increasing the capacity of each cell 22 individually, and thus increasing the actual usable capacity of the battery pack 20.

[0067] Of course, it is understood that in another embodiment, the coil assembly 30 may include at least two sets of coils arranged sequentially along a first direction A, and at least two sets of coils arranged sequentially along a second direction B. The design of the number and position of the at least two sets of coils arranged sequentially along the second direction B is similar to the design of the number and position of the at least two sets of coils arranged sequentially along the first direction A, and will not be described again here.

[0068] Each of the aforementioned battery cells 22 includes four side surfaces connected in sequence, wherein the area of ​​two opposite side surfaces is larger than the area of ​​the other two opposite side surfaces. That is, these two side surfaces constitute the large surface of the battery cell 22. Specifically, the first direction A can be perpendicular to the large surface of the battery cell 22, thus, a constant magnetic field is applied at least on both sides of the large surface of the battery cell 22.

[0069] In the above embodiment, the area of ​​the side of the battery cell 22 facing the adjacent coil 31 can be larger than the area of ​​the coil 31 facing that side. In this way, the two coils 31 can be wrapped around the outer periphery of the battery cell 22.

[0070] Alternatively, the area of ​​the side of the cell 22 facing the adjacent coil 31 can be less than or equal to the area of ​​the coil 31 facing that side. In this case, the coil 31 is arranged parallel to the adjacent side, that is, the plane containing the coil 31 is arranged parallel to the side. In one embodiment, the area of ​​the coil 31 can cover 85% of the side.

[0071] In addition, the battery pack 20 also includes a heat insulation structure for preventing heat from the two coils 31 from being transferred to the at least one cell 22.

[0072] Figure 7 This is a schematic diagram of another battery pack provided in an embodiment of this application. Figure 8 for Figure 7 An exploded view of the battery pack. (See attached image.) Figure 7 and Figure 8As shown, in one embodiment, the heat insulation structure can be a heat insulation layer 23. A heat insulation layer 23 is provided between adjacent battery cells 22 and coils 31, thereby isolating the heat generated by the coils 31 from the battery cells 22 and preventing thermal runaway of the battery cells 22 due to excessive temperature. Simultaneously, the heat insulation layer 23 also acts as a buffer, preventing significant restraint from the coils 31 when the battery cells 22 expand, thus avoiding stress concentration within the battery cells 22 and lithium plating. Specifically, the heat insulation layer 23 can be heat insulation foam.

[0073] Since the coil assembly 30 generates heat after being energized, the battery pack 20 may also include a liquid cooling plate 24 to prevent overheating of the coil assembly 30 from affecting the battery cell 22. The liquid cooling plate 24 is disposed on one side of the coil assembly 30 and is thermally connected to the coil 31. Specifically, the thermal connection between the liquid cooling plate 24 and the coil 31 can be direct contact; alternatively, the thermal connection between the liquid cooling plate 24 and the coil 31 can also be achieved through a heat-conducting element 241. For example, in one embodiment, the heat-conducting element 241 can be formed using thermally conductive adhesive with a thermal conductivity greater than or equal to 0.5 W / (mK). The surface of the liquid cooling plate 24 is provided with multiple heat-conducting elements 241, the number of which corresponds one-to-one with the number of coil groups 31. Therefore, one heat-conducting element 241 is provided for each group of coils, which can guide the heat from each coil 31 of that group of coils to the liquid cooling plate 24. These heat-conducting elements 241 can be arranged sequentially along the first direction A, and each heat-conducting element 241 extends along the second direction B, thus the heat-conducting element 241 is elongated. Each heat-conducting element 241 is connected to each coil 31 of a corresponding set of coils. In this embodiment, the heat-conducting element 241 can both realize heat transfer between the coil 31 and the liquid cooling plate 24, and also fix the coil 31 and the liquid cooling plate 24 relative to each other.

[0074] Figure 9 This is a schematic diagram of another battery pack provided in an embodiment of this application. Figure 10 for Figure 9 An exploded view of the battery pack. (See attached image.) Figure 9 and Figure 10As shown, in another embodiment, the liquid cooling plate 24 can be in a bent structure, so the heat insulation structure may consist only of the liquid cooling plate 24. Specifically, the liquid cooling plate 24 is located between the battery cell 22 and the adjacent coil 31. One end of the liquid cooling plate 24 is bent towards each coil 31 along a first direction A and is thermally connected to each coil 31. In this embodiment, the liquid cooling plate 24 is disposed between the battery cell 22 and the adjacent coils 31 on both sides, and the liquid cooling plate 24 is bent towards the adjacent coils 31. Between two adjacent batteries 22, the liquid cooling plate 24 has a U-shaped structure. Along the first direction A, the liquid cooling plates 24 located on both sides of the plurality of batteries 22 have an L-shaped structure. In this way, the bent liquid cooling plate 24 can dissipate heat to the adjacent two side surfaces of the coil 31, thereby improving the heat dissipation efficiency of the coil assembly 30.

[0075] Figure 11 This is a schematic diagram of another battery pack provided in an embodiment of this application. (See diagram below.) Figure 11 As shown, in another embodiment, the thermal insulation structure includes a plurality of first liquid cooling plates 242 and a second liquid cooling plate 243. A first liquid cooling plate 242 is disposed between the battery cell 22 and the adjacent coil 31, and the second liquid cooling plate 243 is located on one side of the plurality of first liquid cooling plates 242 and exchanges heat with the plurality of first liquid cooling plates 242.

[0076] In some other embodiments, among the multiple cells 22, a heat insulation layer 23 may be provided between a portion of the cells 22 and the adjacent coil 31, and a liquid cooling plate 24 may be provided between another portion of the cells 22 and the adjacent coil 31. This structural design can reduce the manufacturing cost of the heat insulation structure while achieving heat dissipation.

[0077] A thermally conductive material 244 is disposed between at least one of the aforementioned battery cells 22 and the liquid cooling plate 24. This thermally conductive material 244 can not only accelerate the heat exchange between the battery cell 22 and the liquid cooling plate 24, but also play a buffering role, thereby preventing the battery cell 22 from being significantly suppressed by the liquid cooling plate 24 when it expands, which would lead to stress concentration inside the battery cell 22 and lithium plating.

[0078] Each of the at least one battery cell 22 includes four side surfaces connected in sequence. Two of these side surfaces are arranged opposite each other along a first direction A, and the other two side surfaces are arranged opposite each other along a second direction B. The area of ​​the two side surfaces is larger than the area of ​​the other two side surfaces, and the two side surfaces are respectively positioned facing the two coils 31. In this embodiment, the large surfaces of the coils 31 and the battery cells 22 are arranged opposite each other, which allows a constant magnetic field to act on the electrode material of the large surface surface and also benefits the overall size of the multiple battery cells 22 and the coil assembly 30.

[0079] In addition, to prevent the coil assembly 30 from colliding with the housing 21, a buffer plate 25 is provided between the coil assembly 30 and the inner wall of the housing 21.

[0080] Each coil 31 of the coil assembly 30 may include a hollow copper tube covered with an insulating layer to prevent damage to the battery cell 22 in the event of a short circuit in the coil 31. In the battery pack 20, the coils 31 in each group are connected in series, and multiple groups of coils are connected in parallel, ultimately connected to the coil power supply via port 32. When the coil assembly 30 is located within the battery pack 20, the coil power supply can be located within the cabinet 11, with port 32 passing through the outer casing 21 of the battery pack 20 and connected to the coil power supply; alternatively, the coil power supply can also be located within the outer casing 21 and adjacent to the battery management unit.

[0081] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A battery pack, characterized in that, The battery pack includes at least two sets of first coils arranged along a first direction. Each set of first coils includes at least one first coil. A first cell is disposed between any two adjacent sets of first coils. The two sets of first coils are symmetrically arranged with respect to the first cell. The two sets of first coils are used to apply a constant magnetic field to the first cell when current is applied.

2. The battery pack as described in claim 1, characterized in that, The battery pack further includes at least two sets of second coils arranged along a second direction, which is perpendicular to the first direction. Each set of the at least two sets of second coils includes at least one second coil. A second cell is disposed between any two adjacent sets of the at least two sets of second coils. The two sets of second coils are symmetrically arranged with respect to the second cell. The two sets of second coils are used to apply a constant magnetic field to the second cell when current is applied.

3. The battery pack as described in claim 2, characterized in that, The at least two sets of first coils are connected in parallel, and any one of the at least two sets of first coils includes at least two first coils, the at least two first coils are arranged along the second direction and the at least two first coils are connected in series. The at least two sets of second coils are connected in parallel, and any one set of the at least two sets of second coils includes at least two second coils. The at least two second coils are arranged along the first direction and are connected in series.

4. The battery pack as described in claim 2 or 3, characterized in that, A first heat insulation layer is provided between the first battery cell and the two sets of first coils, and a second heat insulation layer is provided between the second battery cell and the two sets of second coils.

5. The battery pack as described in claim 2 or 3, characterized in that, The outer surface of each of the at least two sets of first coils and each of the at least two sets of second coils is covered with an insulating layer.

6. The battery pack as described in any one of claims 1 to 3, characterized in that, During the charging or discharging process of the battery pack, a constant current is passed through the first coil.

7. The battery pack as described in any one of claims 1 to 3, characterized in that, The battery pack includes two sets of first coils arranged along the first direction, with a plurality of first cells disposed between the two sets of first coils; and / or, The battery pack includes two sets of second coils arranged along a second direction, with a plurality of second cells disposed between the two sets of second coils, the second direction being perpendicular to the first direction.

8. The battery pack as described in any one of claims 1 to 3, characterized in that, The first battery cell includes four sides connected in sequence. Two of the four sides are arranged opposite each other along the first direction, and the other two sides are arranged opposite each other along the second direction, which is perpendicular to the first direction. The area of ​​the two sides is larger than the area of ​​the other two sides.

9. The battery pack as described in claim 8, characterized in that, The area of ​​any one of the two sets of first coils shall cover at least 85% of any one of the two sets of sides of the first cell.

10. The battery pack according to any one of claims 1 to 3, characterized in that, The battery pack also includes a first liquid cooling plate located at the bottom of the first cell, and the first liquid cooling plate is thermally connected to each of the at least two sets of first coils.

11. The battery pack as claimed in claim 10, characterized in that, A thermally conductive adhesive is provided between the liquid cooling plate and each of the first coils, and the thermal conductivity of the thermally conductive adhesive is greater than or equal to 0.5 W / (mK).

12. The battery pack as described in any one of claims 1 to 3, characterized in that, The battery pack has a port, and the at least two sets of first coils are connected to the port.

13. The battery pack as described in any one of claims 1 to 3, characterized in that, The battery pack also includes a second liquid cooling plate corresponding to each group of first coils. The second liquid cooling plate has a U-shaped structure and is sandwiched between opposite sides of each group of first coils. The second liquid cooling plate is located between the first cell and each group of first coils.

14. The battery pack as claimed in claim 13, characterized in that, A thermally conductive material is disposed between the second liquid cooling plate and the first battery cell.

15. An energy storage cabinet, characterized in that, Includes a cabinet, the cabinet housing at least one battery pack as claimed in any one of claims 1 to 14.

16. An energy storage cabinet, characterized in that, The device includes a cabinet that houses at least one battery pack; for each of the at least one battery pack, the cabinet is provided with at least one pair of coils located outside each battery pack and symmetrically arranged with respect to each battery pack, the at least one pair of coils being used to apply a constant magnetic field to each battery pack when an electric current is applied.

17. The energy storage cabinet as described in claim 16, characterized in that, The outer shell of the battery pack is made of a material with a magnetic permeability greater than or equal to 4π × 10⁻⁶. -7 H / m, and less than or equal to 4π×10 -5 Materials with H / m.

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