Battery module

Abstract

The utility model provides a battery module, and relates to the technical field of lithium battery production, the battery module comprises a battery module main body and a gas-liquid main pipe, the gas-liquid main pipe is provided with at least one gas-liquid branch pipe, and each battery cell group is correspondingly provided with at least one gas-liquid branch pipe. The gas-liquid branch pipe is connected with the liquid injection port assembly; and the liquid injection port assembly enables the interior of the battery cell to be communicated with the gas-liquid branch pipe. The battery module provided by the utility model is provided with at least one battery cell group, a liquid injection port assembly is arranged on a battery cell cover plate assembly of a battery cell in the battery cell group, each battery cell is connected with a gas-liquid branch pipe through the liquid injection port assembly, and then the gas-liquid branch pipe is connected with a gas-liquid main pipe; therefore, each battery cell in the battery cell group is connected with the gas-liquid main pipe, and the gas-liquid main pipe is used for being connected with the balance tank, so that gas-liquid balance among the plurality of battery cells can be realized.

Description

Technical Field

[0001] This utility model relates to the technical field of lithium battery production, and in particular to a battery module. Background Technology

[0002] Currently, lithium-ion battery modularization is carried out after the cells are manufactured. Cells are then categorized based on parameters such as capacity, voltage, and internal resistance before being matched into modules. During cell manufacturing and categorization, the reference data for categorization suffers from short-term stability issues. This means that while batteries in the same module may have similar parameters when matched, after a period of operation, inconsistencies in cell manufacturing processes lead to inconsistent cell performance degradation, affecting the overall lifespan of the module.

[0003] After battery cells are assembled into modules, the internal state of each cell is independent during subsequent operation, and the consistency of the cells depends entirely on their factory condition. However, due to inevitable defects in the manufacturing process, the differences in consistency will become increasingly apparent after the battery cell modules have been used for a period of time. For example, if a cell has less electrolyte than other cells in the same module, the disadvantage of less electrolyte will become more and more obvious during long-term use, and the cell's performance will experience a significant drop.

[0004] After the cells are modularized, the environment in which the cells in the entire module are used cannot be completely consistent. When the heat dissipation environment of a certain cell in the module is insufficient, the aggravation of side reactions after a period of use will lead to an increase in the amount of gas produced inside. At this time, the gas-liquid system of each cell is separate and cannot be balanced. Utility Model Content

[0005] The purpose of this invention is to provide a battery module to alleviate the technical problem of the inability to achieve consistency among multiple battery cells after they are in operation.

[0006] This utility model provides a battery module, including a battery module body and a gas-liquid main pipe. The battery module body includes at least one cell group, and the cell group includes multiple cells with positive and negative electrodes.

[0007] The battery cell includes a battery cell cover assembly, the battery cell cover assembly includes a battery cell cover body, and a liquid injection port assembly is provided on the battery cell cover body;

[0008] The main gas-liquid pipe is provided with at least one gas-liquid branch pipe, and each of the battery cells is provided with at least one gas-liquid branch pipe, and the gas-liquid branch pipe is connected to the liquid injection port assembly.

[0009] The liquid injection port assembly connects the inside of the battery cell to the gas-liquid distribution pipe.

[0010] In an optional embodiment, the injection port assembly includes an injection connector and a fixing plate; the main body of the cell cover plate is provided with an injection hole, the injection connector is assembled in the injection hole, and both the upper and lower ends of the injection connector extend out of the injection hole;

[0011] The fixing plate is located at the lower end of the liquid injection connector, and a supporting annular plate is located at the upper end of the fixing plate. The supporting annular plate abuts against the main body of the battery cell cover.

[0012] In an optional embodiment, the injection connector is provided with a first through hole, and the fixed pressure plate is provided with a second through hole that is concentric with the first through hole.

[0013] In an optional embodiment, the liquid injection connector includes a connector body, and a lower snap-fit ​​protrusion is provided at the lower end of the connector body;

[0014] The fixed pressure plate has a lower mounting groove, and the lower snap-fit ​​protrusion is fitted into the lower mounting groove.

[0015] In an optional embodiment, the upper end of the connector body is provided with an upper snap-fit ​​protrusion;

[0016] A connecting cap is provided on the gas-liquid split pipe. The connecting cap is provided with a first assembly hole and a second assembly hole is provided inside the first assembly hole. The inner diameter of the first assembly hole matches the outer diameter of the main body of the connector.

[0017] The inner diameter of the second mounting hole matches the outer diameter of the upper snap-fit ​​protrusion.

[0018] In an optional embodiment, at least two mounting grooves are evenly provided on the upper snap-fit ​​protrusion;

[0019] An upper reinforcing ring is provided on the upper surface of the lower snap-fit ​​protrusion; a reinforcing rib is provided inside the upper reinforcing ring, and one end of the reinforcing rib is connected to one end of the connector body, and the other end is connected to the upper reinforcing ring.

[0020] The lower end face of the battery cell cover plate body is provided with a first mounting groove for assembling the upper reinforcing ring and a second mounting groove for assembling the reinforcing rib; and the first mounting groove and the second mounting groove are connected.

[0021] In an optional embodiment, multiple cells of the cell group are connected in series, and each cell group is provided with two gas-liquid distribution pipes.

[0022] In an optional embodiment, multiple cells of the battery cell group are connected in parallel in sequence, and each battery cell group is provided with a corresponding gas-liquid distribution pipe.

[0023] The battery module provided by this utility model has at least one cell group. The cell cover plate assembly of the cell in the cell group is provided with a liquid injection port assembly. Each cell is connected to the gas-liquid manifold through the liquid injection port assembly, and the gas-liquid manifold is then connected to the gas-liquid main pipe. In this way, each cell in the cell group is connected to the gas-liquid main pipe, which is used to connect to the balance tank. This enables gas-liquid balance among multiple cells, allowing the electrolyte to be replenished and the side reaction gases to be discharged before the cells lose their normal cycle performance, thus maintaining the consistent performance of the cells in the entire module. Attached Figure Description

[0024] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 A schematic diagram of the battery module is provided for an embodiment of this utility model;

[0026] Figure 2 for Figure 1 The diagram shows a structural schematic of the battery module from another angle.

[0027] Figure 3 for Figure 1 A schematic diagram of the cell cover assembly of the battery module shown;

[0028] Figure 4 for Figure 3 The diagram shows the structural schematic of the AA section of the battery cell cover assembly.

[0029] Figure 5 for Figure 4 The diagram shows a partial enlarged view of section B of the structural schematic diagram of section AA of the battery cell cover assembly shown.

[0030] Figure 6 for Figure 1 A schematic diagram of the main structure of the cell cover plate of the battery module shown;

[0031] Figure 7 for Figure 6 A partial enlarged view of point C in the structural schematic diagram of the main body of the battery cell cover shown;

[0032] Figure 8 for Figure 1 The diagram shows the structure of the electrolyte inlet assembly of the battery module.

[0033] Figure 9 for Figure 8 A schematic diagram of the injection port assembly's injection connector;

[0034] Figure 10 for Figure 8 A schematic diagram of the structure of the fixing plate of the injection port assembly shown;

[0035] Figure 11 for Figure 1 The diagram shows the structure of the connection cap for the battery module.

[0036] Icons: 100-Cell assembly; 101-Cell; 200-Gas-liquid manifold; 300-Gas-liquid main pipe; 400-Connecting cap; 401-First assembly hole; 402-Second assembly hole; 500-Cell cover plate body; 501-Injection hole; 502-Second assembly groove; 503-First assembly groove; 600-Injection port assembly; 601-Injection connector; 6011-Connector body; 6012-Assembly groove; 6013-Reinforcing rib; 6014-Upper reinforcing ring; 6015-Lower snap-fit ​​protrusion; 6016-Upper snap-fit ​​protrusion; 6017-First through hole; 602-Fixing pressure plate; 6021-Lower assembly groove; 6022-Second through hole; 6023-Supporting ring plate. Detailed Implementation

[0037] The terms “first,” “second,” “third,” etc., are used only for distinguishing descriptions and do not indicate a sequence number, nor should they be interpreted as indicating or implying relative importance.

[0038] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0039] In the description of this application, it should be noted that the terms "inner", "outer", "left", "right", "upper", "lower", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0040] In the description of this application, unless otherwise expressly specified and limited, the terms “set up,” “install,” “connect,” and “link” shall be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection; as a mechanical connection or an electrical connection; as a direct connection or an indirect connection through an intermediate medium; or as a connection within two components.

[0041] The technical solution of this application will now be clearly and completely described with reference to the accompanying drawings.

[0042] Reference Figures 1-11 This utility model provides a battery module, including a battery module body and a gas-liquid main pipe 300. The battery module body includes at least one cell group 100, and the cell group 100 includes a plurality of cells 101 with positive and negative electrodes.

[0043] The battery cell 101 includes a battery cell 101 cover plate assembly, which includes a battery cell cover plate body 500 and a liquid injection port assembly 600 is provided on the battery cell cover plate body 500.

[0044] At least one gas-liquid branch pipe 200 is provided on the gas-liquid main pipe 300, and each of the battery cell groups 100 is provided with at least one gas-liquid branch pipe 200. The gas-liquid branch pipe 200 is connected to the liquid injection port assembly 600.

[0045] The liquid injection port assembly 600 connects the inside of the battery cell 101 with the gas-liquid distribution pipe 200.

[0046] In some embodiments, the battery module body of the battery module has one or more cell groups 100, the cell group 100 has multiple cells 101 with positive and negative electrodes, the cell 101 cover assemblies of the multiple cells 101 of the cell group 100 have the same orientation, and each cell 101 cover assembly is provided with a liquid injection port assembly 600.

[0047] The battery cells 101 in the battery cell group 100 have the same structure. The gas-liquid main pipe 300 is used to connect to the balance tank. One or more gas-liquid branch pipes 200 are provided on the gas-liquid main pipe 300. Each battery cell group 100 is provided with one or more gas-liquid branch pipes 200.

[0048] All cells 101 in the cell assembly 100 are connected to the gas-liquid main pipe 300 via gas-liquid manifolds 200, and the gas-liquid main pipe 300 is connected to the balance tank. This allows multiple cells 101 to be connected, enabling the timely discharge of side reaction gases generated within the cells 101 and replenishment of the electrolyte within the cells 101, maintaining the uniformity of the entire cell assembly 100. The gas-liquid main pipes 300 between adjacent cell assemblies 100 are also connected, ensuring the uniformity of the cells 101 within the entire battery module. This prevents the shortcomings of individual cells 101 with insufficient electrolyte from becoming more apparent, thus avoiding a significant drop in the performance of the cells 101. Furthermore, since the environment in which the cells 101 of the entire battery module are used cannot be completely uniform, if the heat dissipation environment of a certain cell 101 in the battery module is insufficient, the intensification of side reactions after a period of use will lead to an increase in the amount of gas generated inside. This gas is discharged through the gas-liquid manifolds 200, effectively reducing the pressure inside the cell 101.

[0049] Reference Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 In an optional embodiment, the liquid injection port assembly 600 includes a liquid injection connector 601 and a fixing plate 602; the battery cell cover body 500 is provided with a liquid injection hole 501, the liquid injection connector 601 is assembled in the liquid injection hole 501, and both the upper and lower ends of the liquid injection connector 601 extend out of the liquid injection hole 501.

[0050] The fixed pressure plate 602 is disposed at the lower end of the liquid injection connector 601, and a supporting annular plate 6023 is disposed at the upper end of the fixed pressure plate 602, the supporting annular plate 6023 abutting against the battery cell cover body 500.

[0051] The liquid injection port assembly 600 includes a liquid injection connector 601 and a fixing plate 602; wherein, the liquid injection connector 601 can be inserted into the liquid injection hole 501 from the lower end of the cell cover body 500, and the upper end of the liquid injection connector 601 extends out of the liquid injection hole 501.

[0052] The fixing plate 602 can be assembled at the lower end of the liquid injection connector 601 and can be connected to the cell cover body 500. This can effectively prevent the liquid injection connector 601 from detaching from the liquid injection hole 501, so that the liquid injection connector 601 can be firmly fixed on the liquid injection hole 501. When liquid injection is required, the liquid injection nozzle can be inserted into the through hole of the liquid injection connector 601, thus changing from the traditional extrusion connection to a corresponding connection method. During the liquid injection process, the connection method between the liquid injection nozzle and the liquid injection connector 601 changes from pure extrusion to wrapping, improving airtightness.

[0053] In an optional embodiment, the injection connector 601 is provided with a first through hole 6017, and the fixed pressure plate 602 is provided with a second through hole 6022 that is concentrically arranged with the first through hole 6017.

[0054] The fixed pressure plate 602 has a second through hole 6022, which is set to correspond to the first through hole 6017. This avoids the installation of the fixed pressure plate 602 from affecting the injection of electrolyte.

[0055] In an optional embodiment, the liquid injection connector 601 includes a connector body 6011, and a lower snap-fit ​​protrusion 6015 is provided at the lower end of the connector body 6011.

[0056] The fixed pressure plate 602 has a lower mounting groove 6021, and the lower snap-fit ​​protrusion 6015 is mounted in the lower mounting groove 6021.

[0057] In some embodiments, the lower end of the connector body 6011 of the injection connector 601 has a lower locking protrusion 6015, the outer diameter of which is larger than the inner diameter of the injection hole 501; the lower locking protrusion 6015 cannot enter the injection hole 501.

[0058] The fixed pressure plate 602 is provided with a lower mounting groove 6021, and the lower snap-fit ​​protrusion 6015 can be assembled in the lower mounting groove 6021. The second through hole 6022 on the fixed pressure plate 602 is correspondingly provided with the first through hole 6017. The fixed pressure plate 602 is connected to the cell cover plate body 500, so that the liquid injection connector 601 can be fixed on the cell cover plate body 500, so that the liquid injection connector 601 cannot be separated from the liquid injection hole 501.

[0059] The fixing plate 602 is generally made of plastic. The fixing plate 602 and the main body 500 of the battery cell cover can be fixed by adhesive or plastic welding.

[0060] To better connect the connecting cap 400 to the injection connector 601, the connecting cap 400 has a first mounting hole 401 and a second mounting hole 402. The upper snap-fit ​​protrusion 6016 of the injection connector 601 is assembled into the first mounting hole 401 and into the second mounting hole 402 by an interference fit. The inner diameter of the second mounting hole 402 is larger than the inner diameter of the first mounting hole 401. After the upper snap-fit ​​protrusion 6016 is assembled into the second mounting hole 402, the upper snap-fit ​​protrusion 6016 is not easy to pass through the first mounting hole 401, that is, the connecting cap 400 is not easy to detach from the injection connector 601.

[0061] Reference Figure 9 , Figure 10 and Figure 11 In an optional embodiment, the upper end of the connector body 6011 is provided with an upper snap-fit ​​protrusion 6016;

[0062] A connecting cap 400 is provided on the gas-liquid split pipe 200. The connecting cap 400 is provided with a first assembly hole 401 and a second assembly hole 402 is provided in the first assembly hole 401. The inner diameter of the first assembly hole 401 matches the outer diameter of the connector body 6011.

[0063] The inner diameter of the second mounting hole 402 matches the outer diameter of the upper snap-fit ​​protrusion 6016.

[0064] In an optional embodiment, at least two mounting grooves 6012 are evenly provided on the upper snap-fit ​​protrusion 6016;

[0065] An upper reinforcing ring 6014 is provided on the upper surface of the lower snap-fit ​​protrusion 6015; a reinforcing rib 6013 is provided inside the upper reinforcing ring 6014, and one end of the reinforcing rib 6013 is connected to one end of the connector body 6011, and the other end is connected to the upper reinforcing ring 6014.

[0066] The lower end face of the battery cell cover plate body 500 is provided with a first mounting groove 503 for mounting the upper reinforcing ring 6014 and a second mounting groove 502 for mounting the reinforcing rib 6013; and the first mounting groove 503 and the second mounting groove 502 are connected.

[0067] The lower end face of the cell cover body 500 is provided with a first assembly groove 503 and a second assembly groove 502. When the liquid injection connector 601 is assembled from the lower end of the cell cover body 500 into the liquid injection hole 501, the upper reinforcing ring 6014 is assembled into the first assembly groove 503, and the reinforcing rib 6013 is assembled into the second assembly groove 502, thus assembling the liquid injection connector 601 into the liquid injection hole 501. The reinforcing rib 6013 prevents the liquid injection connector 601 from rotating, ensuring that the liquid injection connector 601 and the liquid injection hole 501 do not rotate relative to each other. This effectively ensures that the liquid injection connector 601 will not rotate after assembly, thus preventing wear and leakage.

[0068] Reference Figure 1 and Figure 2 In an optional embodiment, a plurality of battery cells 101 of the battery cell group 100 are connected in series, and each battery cell group 100 is provided with two gas-liquid distribution pipes 200.

[0069] In an optional embodiment, a plurality of the battery cells 101 of the battery cell group 100 are connected in parallel in sequence, and each battery cell group 100 is provided with a corresponding gas-liquid separator 200.

[0070] The battery cells 101 within the battery cell assembly 100 are connected in series or in parallel. When the battery cells 101 within the battery cell assembly 100 are connected in parallel, the liquid injection port assemblies 600 on multiple battery cells 101 are in a straight line, and one gas-liquid separator 200 can be connected to the liquid injection port assemblies 600 of multiple battery cells 101 simultaneously. When the battery cells 101 within the battery cell assembly 100 are connected in series, the liquid injection port assemblies 600 of adjacent battery cells 101 are staggered, that is, the liquid injection port assemblies 600 of multiple battery cells 101 are arranged in two rows, and one battery cell assembly 100 requires two gas-liquid separators 200.

[0071] The battery module provided by this utility model has at least one cell group 100. The cell 101 cover plate assembly of the cell 101 in the cell group 100 is provided with a liquid injection port assembly 600. Each cell 101 is connected to a gas-liquid manifold 200 through the liquid injection port assembly 600, and the gas-liquid manifold 200 is then connected to a gas-liquid main pipe 300. In this way, each cell 101 in the cell group 100 is connected to the gas-liquid main pipe 300. The gas-liquid main pipe 300 is used to connect to the balance tank. This can realize the gas-liquid balance among multiple cells 101, so that the electrolyte is replenished and the side reaction gases are discharged before the cells 101 lose their normal cycle performance, and maintain the consistent performance of the cells 101 in the entire module.

[0072] The cells 101 in the cell group 100 of the battery module are connected to the gas-liquid main pipe 300 through the gas-liquid manifold 200. The gas-liquid main pipe 300 is then connected to the balance tank. The balance tank regulates the electrolyte and gas to make the cells 101 in the battery module connected. After the cells 101 are modularized, the gas-liquid balance intervention can be performed in a timely manner according to the actual cycle performance of the modular cells 101. Before the cells 101 deviate from normal cycle performance, the electrolyte is replenished and the side reaction gases are discharged, maintaining the consistent performance of the cells 101 in the entire module.

[0073] The battery module can regulate gas and liquid, which improves the independence between individual cells after the current 101 module is modularized.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A battery module, characterized in that, It includes a battery module body and a gas-liquid main pipe (300). The battery module body includes at least one cell group (100), and the cell group (100) includes a plurality of cells (101) with positive and negative electrodes. The battery cell (101) includes a battery cell (101) cover plate assembly, which includes a battery cell cover plate body (500) and an injection port assembly (600) is provided on the battery cell cover plate body (500). At least one gas-liquid branch pipe (200) is provided on the gas-liquid main pipe (300), and each of the battery cell groups (100) is provided with at least one gas-liquid branch pipe (200), and the gas-liquid branch pipe (200) is connected to the liquid injection port assembly (600). The liquid injection port assembly (600) connects the inside of the battery cell (101) to the gas-liquid separator (200).

2. The battery module according to claim 1, characterized in that, The liquid injection port assembly (600) includes a liquid injection connector (601) and a fixing plate (602); the battery cell cover body (500) is provided with a liquid injection hole (501), the liquid injection connector (601) is assembled in the liquid injection hole (501), and both the upper and lower ends of the liquid injection connector (601) extend out of the liquid injection hole (501). The fixed pressure plate (602) is located at the lower end of the liquid injection connector (601), and a supporting annular plate (6023) is provided at the upper end of the fixed pressure plate (602), which abuts against the main body (500) of the battery cell cover plate.

3. The battery module according to claim 2, characterized in that, The liquid injection connector (601) is provided with a first through hole (6017), and the fixed pressure plate (602) is provided with a second through hole (6022) that is concentric with the first through hole (6017).

4. The battery module according to claim 3, characterized in that, The liquid injection connector (601) includes a connector body (6011), and a lower snap-fit ​​protrusion (6015) is provided at the lower end of the connector body (6011). The fixed pressure plate (602) has a lower mounting groove (6021), and the lower snap-fit ​​protrusion (6015) is mounted in the lower mounting groove (6021).

5. The battery module according to claim 4, characterized in that, The upper end of the connector body (6011) is provided with an upper snap-fit ​​protrusion (6016). A connecting cap (400) is provided on the gas-liquid split pipe (200). The connecting cap (400) is provided with a first assembly hole (401). A second assembly hole (402) is provided in the first assembly hole (401). The inner diameter of the first assembly hole (401) matches the outer diameter of the connector body (6011). The inner diameter of the second mounting hole (402) matches the outer diameter of the upper snap-fit ​​protrusion (6016).

6. The battery module according to claim 5, characterized in that, At least two mounting slots (6012) are evenly provided on the upper snap-fit ​​protrusion (6016). An upper reinforcing ring (6014) is provided on the upper surface of the lower snap-fit ​​protrusion (6015); a reinforcing rib (6013) is provided inside the upper reinforcing ring (6014), and one end of the reinforcing rib (6013) is connected to one end of the connector body (6011), and the other end is connected to the upper reinforcing ring (6014). The lower end face of the battery cell cover plate body (500) is provided with a first mounting groove (503) for mounting the upper reinforcing ring (6014) and a second mounting groove (502) for mounting the reinforcing rib (6013); and the first mounting groove (503) and the second mounting groove (502) are connected.

7. The battery module according to claim 6, characterized in that, The multiple cells (101) of the cell group (100) are connected in series, and each cell group (100) is provided with two gas-liquid separators (200).

8. The battery module according to claim 6, characterized in that, The multiple cells (101) of the cell group (100) are connected in parallel in sequence, and each cell group (100) is provided with a corresponding gas-liquid separator (200).

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