Battery module and battery pack

Abstract

To provide a battery module and a battery pack.SOLUTION: A battery module includes a plurality of battery cells and a first fireproof layer, each the battery cell is arranged in sequence, and the first fireproof layer is provided at the top of each battery cell, and the first fireproof layer is bonded to the top of each battery cell. According to the present application, fireproof performance of the battery module can be improved and safety of using the battery module can be enhanced.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present application relates to the field of battery technology, and in particular to battery modules and battery packs. [Background technology]

[0002] A battery module includes a plurality of battery cells, which are connected to each other in series or parallel. Because the arrangement of the battery cells inside the battery module is compact, if a thermal runaway occurs in a battery cell, the heat will be transferred to other battery cells, causing thermal runaway in the other battery cells, resulting in a chain reaction of thermal runaway, which will ultimately cause the entire battery module to catch fire and even explode, seriously affecting the safety of the use of the battery module. Summary of the Invention [Problem to be solved by the invention]

[0003] The present application provides a battery module and a battery pack that can improve the fire prevention performance of the battery module and the usage safety of the battery module. [Means for solving the problem]

[0004] In a first aspect of the present application, a battery module is provided, the battery module including a plurality of battery cells and a first fire-resistant layer, each of the battery cells being arranged in sequence, the first fire-resistant layer being provided on a top of the battery cells, and the first fire-resistant layer being bonded to a top surface of each of the battery cells.

[0005] Preferably, a through hole is provided in the first fireproof layer, and a pole of the battery cell is drilled into the through hole and protrudes from a surface of the first fireproof layer.

[0006] Preferably, the battery module further includes two end plates, the end plates being provided at both ends of the battery cells along the arrangement direction of the battery cells, and a second fireproof layer being provided between the battery cells and the end plates.

[0007] Preferably, both sides of the second fire-resistant layer are adhered to the surface of the end plate and the battery cell, respectively.

[0008] Preferably, a third fire-resistant layer is provided between adjacent battery cells.

[0009] Preferably, the upper end of the third fire-resistant layer contacts the lower surface of the first fire-resistant layer.

[0010] Preferably, the lower end of the third fireproof layer does not extend beyond the lower end of the battery cell.

[0011] Preferably, both sides of the third fire-resistant layer are respectively adhered to the surfaces of the adjacent battery cells.

[0012] Preferably, the first fireproof layer, the second fireproof layer or the third fireproof layer comprises a mica sheet.

[0013] In a second aspect of the present application, a battery pack is provided, the battery pack including any battery module provided by the present application, the number of the battery modules being at least two, and a plurality of the battery modules being arranged vertically stacked. Effect of the Invention

[0014] The technical solution of the present application can achieve the following beneficial effects: The battery module according to the present application includes a plurality of battery cells and a first fireproof layer, the battery cells are arranged in sequence, and the first fireproof layer is provided on the top of the battery cells, and the first fireproof layer is bonded to the top surface of each of the battery cells. By providing the first fireproof layer on the top of the battery cells and bonding the first fireproof layer to the top surface of the battery cells, the first fireproof layer acts as a fireproof and heat-insulating layer on the top of the battery cells, which can not only effectively prevent the spread of flame to areas other than the battery cells, but also delay the spread of flame between the battery cells, thereby avoiding thermal runaway in the entire battery module.

[0015] It is to be understood that the foregoing general description and the following detailed description are exemplary only and are not restrictive of the present application. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a schematic diagram illustrating the configuration of a battery module according to an embodiment of the present application. [Diagram 2] FIG. 2 is an exploded schematic diagram of the battery module shown in FIG. [Diagram 3] FIG. 2 is a schematic diagram showing a partial configuration of the battery module shown in FIG. [Figure 4] FIG. 4 is a schematic diagram showing the configuration of a first fireproof layer in FIG. [Diagram 5] FIG. 4 is a schematic cross-sectional view of FIG. 3. [Figure 6] FIG. 6 is a partial enlarged view of a portion A in FIG. 5. [Figure 7] FIG. 6 is a partial enlarged view of a portion B in FIG. 5.

[0017] The drawings herein are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification serve to explain the principles of the present application. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] In order to make the purpose, technical solution and advantages of the present application clearer, the present application will be described in more detail below in conjunction with the drawings and examples. It should be understood that the specific examples described herein are merely used to interpret the present application, and are not intended to limit the present application.

[0019] In the description of this application, unless expressly specified and limited, the terms "first" and "second" are used for explanatory purposes only and should not be considered to indicate or imply relative importance. Unless expressly specified or explained, the term "plurality" refers to two or more than two. The terms "connected", "fixed", etc. should be understood in a broad sense, for example, "connected" may be a fixed connection, a detachable connection, or an integral connection, an electrical connection, a direct connection, or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific situation.

[0020] In the description of this specification, directional terms such as "upper" and "lower" described in the embodiments of the present application are described in terms of angles shown in the drawings, and should not be understood as limiting the embodiments of the present application. In addition, when an element is connected to the "upper" or "lower" of another element in the context, it should be understood that it can be directly connected to the "upper" or "lower" of the other element, and can also be indirectly connected to the "upper" or "lower" of the other element via an intermediate element.

[0021] As shown in Figs. 1 and 2, an embodiment of the present application provides a battery module, which includes a plurality of battery cells 1, two end plates 5, two side plates 6, a bus bar member 7, and a top cover 8. The plurality of battery cells 1 are arranged in sequence, for example, the plurality of battery cells 1 may be arranged in sequence along their thickness direction. The end plates 5 are provided at both ends of the battery cells 1 along the arrangement direction of the battery cells 1, and the side plates 6 connect the two end plates 5, so that the end plates 5 and the side plates 6 together form a fixed frame surrounding the battery cells 1, and the bus bar member is provided on the top of the battery cells 1 and connected to the poles 11 of each battery cell 1, so as to realize a series-parallel connection between each battery cell 1. The top cover 8 is provided on the top of the bus bar member to form the top of the battery module. A heating sheet 9 may be further provided on the bottom of the battery module to heat the battery module in a low-temperature environment.

[0022] 2 to 7, the battery module according to the embodiment of the present application further includes a first fireproof layer 2, which is provided on the top of the battery cell 1 and is bonded to the top surface of each battery cell 1, that is, the first fireproof layer 2 is in direct contact with the top surface of the battery cell 1, there is no other member between the first fireproof layer 2 and the top surface of the battery cell 1, and the bus bar member 7 and the top cover 8 are all provided outside the first fireproof layer 2. By providing the first fireproof layer 2 on the top of the battery cell 1 and bonding the first fireproof layer 2 to the top surface of the battery cell 1, the first fireproof layer 2 acts as a fireproof and heat-insulating layer on the top of the battery cell 1, which can not only effectively prevent the flame from spreading to areas other than the battery cell 1, but also delay the flame from spreading between the battery cells 1, thereby avoiding thermal runaway in the entire battery module. In other words, the first fire-resistant layer 2 can block the vertical transmission of flame, and the flame cannot spread through the first fire-resistant layer 2 to the top bus bar member 7 and top cover 8, thereby reducing the extent of damage to the battery module; the first fire-resistant layer 2 can delay the lateral transmission of flame, and if thermal runaway occurs in one of the battery cells 1, it becomes difficult for heat to be transmitted laterally to the top of the battery cell 1, thereby preventing the flame from spreading to other battery cells 1 and preventing thermal runaway from occurring throughout the entire battery module.

[0023] As shown in Figures 2 to 5, specifically, the surface of the first fireproof layer 2 is provided as a planar structure, which not only simplifies the configuration of the first fireproof layer 2 and reduces production costs, but also prevents interference between the first fireproof layer 2 and existing components of the battery module (e.g., bus bar member 7, etc.), thereby improving the versatility of the first fireproof layer 2.

[0024] The first fireproof layer 2 may be provided as a continuous fireproof area that simultaneously covers multiple battery cells 1, or may be provided as multiple fireproof areas that are independent of each other, for example, a single first fireproof layer 2 is provided for each battery cell 1. The first fireproof layer 2 may cover only a portion of the top surface of the battery cell 1, or may completely cover the top surface of the battery cell 1. If the first fireproof layer 2 can provide a thermal insulation effect for the top surface of the battery cell 1, the risk of thermal runaway of the battery module can be improved.

[0025] Preferably, the first fireproof layer 2 extends to the edge of the battery cell 1 along the arrangement direction of the battery cells 1, and the first fireproof layer 2 extends to the edge of the battery cell 1 along the length direction of the battery cell 1, thereby forming a continuous fireproof area on the top of the battery cell 1, effectively improving the fireproofing and heat insulation effect, and reducing the risk of thermal runaway in the battery module. Since the edge of the first fireproof layer 2 does not exceed the edge of the battery cell 1, it is possible to avoid the edge of the first fireproof layer 2 being easily damaged due to the occurrence of a hanging point at the edge of the first fireproof layer 2, which would affect the fireproofing and heat insulation effect.

[0026] Furthermore, the first fireproof layer 2 is provided with through holes 21, and the poles 11 of the battery cells 1 are drilled into the through holes 21 and protrude from the surface of the first fireproof layer 2, so that the battery cells 1 are connected to each other outside the first fireproof layer 2, reducing the effect of fire on components other than the battery cells 1 and lowering the risk of thermal runaway in the battery module. The first fireproof layer 2 is also provided with through holes 21, which serve to release pressure and prevent the battery cells 1 from exploding due to thermal runaway.

[0027] Furthermore, by adhering the first fireproof layer 2 to the top surface of the battery cell 1, a tight connection is formed between the first fireproof layer 2 and the top surface of the battery cell 1, thereby preventing the fireproof effect from being affected by relative movement between the first fireproof layer 2 and the battery cell 1 or the occurrence of large gaps.

[0028] Specifically, the first fireproof layer 2 may include a layered sheet-like structure made of a heat insulating material, for example, polyimide resin, phenolic resin, epoxy resin, aluminum oxide, zirconium oxide, boehmite (AlOOH), gibbsite (Al(OH)3), silicon oxide, magnesium oxide (magnesia), calcium oxide, titania, barium titanate, alumina-silica composite oxide, aluminum nitride, boron nitride, silicon, diamond, barium sulfate, calcium fluoride, barium fluoride, kaolin, montmorillonite, bentonite, or feldspar. The first fireproof layer 2 may be provided as a single layer structure or a multi-layer composite structure.

[0029] Preferably, the first fire-resistant layer 2 comprises a mica sheet, the raw material of which is a natural mineral product, the production cost is low, and no pollution occurs during the production process. In addition, the mica sheet has good electrical properties, good heat resistance, stable chemical properties, good mechanical properties, and will not be damaged in the event of thermal runaway.

[0030] As shown in Figures 2 to 5, a second fireproof layer 3 is further provided between the battery cell 1 and the end plate 5. The second fireproof layer 3 provides fireproof and insulating properties to the end of the battery cell 1, preventing the flames from spreading to areas other than the battery cell 1 and reducing the extent of damage to the battery module.

[0031] Furthermore, both sides of the second fireproof layer 3 are adhered to the surfaces of the end plate 5 and the battery cell 1, respectively, and the end plate 5 and the battery cell 1 are integrally formed, thereby controlling the overall dimensions of the battery module and improving the energy density of the battery module.

[0032] Specifically, the second fireproof layer 3 may include a layered sheet-like structure made of a heat insulating material, for example, polyimide resin, phenolic resin, epoxy resin, aluminum oxide, zirconium oxide, boehmite (AlOOH), gibbsite (Al(OH)3), silicon oxide, magnesium oxide (magnesia), calcium oxide, titania, barium titanate, alumina-silica composite oxide, aluminum nitride, boron nitride, silicon, diamond, barium sulfate, calcium fluoride, barium fluoride, kaolin, montmorillonite, bentonite, or feldspar. The second fireproof layer 3 may be provided as a single layer structure or a multi-layer composite structure. The third fireproof layer 4 may be provided as a single layer structure or a multi-layer composite structure.

[0033] Preferably, the second fireproof layer 3 includes a mica sheet, the raw material of which is a natural mineral product, the production cost is low, and no pollution occurs during the production process. In addition, the mica sheet has good electrical properties, good heat resistance, stable chemical properties, good mechanical properties, and will not be damaged in the event of thermal runaway.

[0034] In addition, the second fireproof layer 3 further includes an insulating layer, and the material of the insulating layer includes, but is not limited to, PC, ceramics, PP, nylon, etc. The insulating layer is adhered to the surface of the mica sheet, which can improve the insulating effect between the battery cells 1 and improve the safety performance of the battery module.

[0035] Furthermore, a third fire-resistant layer 4 is provided between adjacent battery cells 1, and the third fire-resistant layer 4 separates the two adjacent battery cells 1 from each other, thereby effectively preventing the spread of flames to the adjacent battery cells 1 and limiting thermal runaway to the range of a single battery cell 1, thereby preventing thermal runaway from occurring throughout the entire battery module.

[0036] As shown in Figure 6, further, the upper end of the third fireproof layer 4 contacts the lower surface of the first fireproof layer 2, so that the third fireproof layer 4 and the first fireproof layer 2 together form multiple independent fireproof and insulating spaces, and one battery cell 1 is housed in each fireproof and insulating space. Since adjacent fireproof and insulating spaces do not communicate with each other, thermal runaway of the battery cell 1 is restricted to within the fireproof and insulating space, and thermal runaway can be prevented from occurring throughout the entire battery module.

[0037] As shown in FIG. 7, the lower end of the third fireproof layer 4 does not exceed the lower end of the battery cell 1, that is, the lower end of the third fireproof layer 4 is aligned with the lower end of the battery cell 1, or a gap is left between the lower end of the third fireproof layer 4 and the lower end of the battery cell 1. On the one hand, high-temperature smoke generated by a fire generally flows upward, which causes the fire to spread upward quickly and is less likely to spread downward. Leaving a small gap at the lower end of the battery cell 1 does not affect the overall fireproof effect, and can also achieve the effects of weight reduction and cost saving. On the other hand, leaving a gap between the lower end of the third fireproof layer 4 and the bottom end of the battery cell 1 can prevent the third fireproof layer 4 from contacting the bottom supporting plane, thereby ensuring that the third fireproof layer 4 is not subjected to a load during transportation or use of the battery module, and preventing the third fireproof layer 4 from being damaged.

[0038] Furthermore, both sides of the third fireproof layer 4 are respectively adhered to the surfaces of the adjacent battery cells 1, and each battery cell 1 is connected and integrated with each other, thereby controlling the spacing between adjacent battery cells 1, and further controlling the overall dimensions of the battery module, and improving the energy density of the battery module.

[0039] Furthermore, regarding the material and configuration of the third fire-resistant layer 4, reference can be made to the second fire-resistant layer 3, and the third fire-resistant layer 4 and the second fire-resistant layer 3 may adopt the same material and structure, or different materials and structures.

[0040] In addition, the present embodiment further provides a battery pack, which includes any of the battery modules provided by the present embodiment, and the number of the battery modules is at least two, and the battery modules are stacked vertically. When a thermal runaway occurs in one battery module in the battery pack, the first fireproof layer 2 in the battery module can effectively prevent the flame from propagating upward, and can prevent the flame from spreading to other battery modules.

[0041] The above description is only a preferred embodiment of the present application, and is not used to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modifications, equivalent replacements, improvements, etc. within the spirit and principle of the present application should be included in the protection scope of the present application. [Explanation of symbols]

[0042] 1- Battery Cell 11-Polar pillar 2-1st fire protection layer 21-Through hole 3-Second fire protection layer 4-Third fire protection layer 5-end plate 6-Side Panel 7-Busbar components 8-Top cover 9-Heated Sheet

Claims

1. A battery module, The battery module includes a plurality of battery cells and a first fireproof layer; Each of the battery cells is arranged in sequence, the first fireproof layer is provided on a top portion of the battery cell, and the first fireproof layer is bonded to a top surface of each of the battery cells; a third fireproof layer is provided between adjacent battery cells; A battery module, characterized in that an upper end of the third fireproof layer contacts a lower surface of the first fireproof layer.

2. A battery module, The battery module includes a plurality of battery cells and a first fireproof layer; Each of the battery cells is arranged in sequence, the first fireproof layer is provided on a top portion of the battery cell, and the first fireproof layer is bonded to a top surface of each of the battery cells; a third fireproof layer is provided between adjacent battery cells; a lower end of the third fireproof layer does not extend beyond a lower end of the battery cell.

3. 3. The battery module according to claim 1, wherein the first fireproof layer has a through hole, and the electrode post of the battery cell is drilled into the through hole and protrudes from a surface of the first fireproof layer.

4. 3. The battery module according to claim 1, further comprising two end plates, the end plates being provided at both ends of the battery cells along an arrangement direction of the battery cells, and a second fireproof layer being provided between the battery cells and the end plates.

5. The battery module according to claim 4 , wherein both sides of the second fire-resistant layer are respectively adhered to the end plate and the battery cell.

6. The battery module according to claim 1 or 2, wherein both sides of the third fire-resistant layer are respectively adhered to the surfaces of the adjacent battery cells.

7. 3 . The battery module according to claim 1 , wherein the first fireproof layer, the second fireproof layer, or the third fireproof layer includes a mica sheet. 4 .

8. A battery pack comprising:

3. A battery pack comprising the battery module according to claim 1, the number of the battery modules being at least two, and the battery modules being stacked in a vertical direction.

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