Battery package

Abstract

A battery package includes: a plurality of secondary battery cells each provided with a plurality of gas discharge ports that open in response to an increase in internal pressure; a lead plate that connects cell end faces of the plurality of secondary battery cells to each other; and an outer case that houses the plurality of secondary battery cells connected by the lead plate. In a state in which the lead plate is fixed to the cell end faces in a manner that partially overlaps with an opening region of at least any one of the plurality of gas discharge ports, each of the plurality of gas discharge ports satisfies that an area of a region of the opening region of at least any one of the plurality of gas discharge ports that is covered by the lead plate is less than 40% of the opening region of each gas discharge port.

Description

Technical Field

[0001] This invention relates to battery packaging. Background Technology

[0002] A battery package that houses multiple rechargeable secondary battery cells, such as lithium-ion secondary batteries, within an outer casing and is used to drive electrical devices is employed in various applications (e.g., Patent Document 1). In such a battery package, if any of the secondary battery cells housed in the outer casing experiences an abnormality and generates heat, it is necessary to prevent the impact from spreading to other adjacent secondary battery cells. Therefore, each secondary battery cell is configured with a gas vent, from which high-temperature, high-pressure gas is released when such gas is generated inside the outer casing of the secondary battery cell. The high-temperature, high-pressure gas released from the secondary battery cell into the outer casing is then discharged to the outside from the outer casing. This gas vent is often located at the electrode end face of the secondary battery cell.

[0003] On the other hand, in order to electrically connect multiple secondary battery cells to each other, lead plates are connected to the electrodes on the end face of the cells. At this time, the lead plates block the gas outlet. When gas is released from the gas outlet, it is blocked by the lead plates. As a result, the high temperature and high pressure gas diffuses to the surroundings, and the negative impact may affect adjacent secondary battery cells.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2022-2199 Summary of the Invention

[0007] One objective of this invention is to provide a battery package that does not easily obstruct gas escape. Another objective is to provide a battery package that reduces the risk of delayed combustion. It should be noted that the description of these objectives and objectives does not preclude the existence of other objectives and objectives. Furthermore, one solution to this invention does not need to solve all of these objectives. Moreover, other objectives besides these can be extracted from the description, drawings, and technical solutions of this invention.

[0008] One aspect of the present invention provides a battery package comprising: a plurality of secondary battery cells, each having a plurality of gas outlets opening in response to an increase in internal pressure on one of the cell end faces; a lead plate connecting the cell end faces of the plurality of secondary battery cells to each other; and an outer housing housing the plurality of secondary battery cells connected by the lead plate, wherein the lead plate is fixed to the cell end face in such a manner that it partially overlaps with the opening area of ​​at least one of the plurality of gas outlets, and each of the plurality of gas outlets satisfies the following condition: the area covered by the lead plate in the opening area of ​​at least one of the plurality of gas outlets is less than 40% of the opening area of ​​each gas outlet.

[0009] According to one aspect of the present invention, the battery package ensures that the opening area of ​​each gas outlet is more than 60% while fixing the lead plate to the end face of the cell, thereby avoiding obstruction of gas discharge and suppressing the dispersion of high temperature and high pressure gas to the surrounding secondary battery cells, thereby improving the safety of the battery package. Attached Figure Description

[0010] Figure 1 This is a perspective view of the battery package according to Embodiment 1.

[0011] Figure 2 yes Figure 1 An exploded perspective view of the battery package.

[0012] Figure 3 yes Figure 2 An exploded perspective view of the battery retainer.

[0013] Figure 4 It means in Figure 3 An exploded perspective view of the leadboard connected to the battery holder containing the secondary battery cells.

[0014] Figure 5 This is a top view showing the end face of a single secondary battery cell.

[0015] Figure 6 This is an exploded perspective view of the battery package of a comparative example.

[0016] Figure 7 yes Figure 6 A magnified perspective top view of the main part of the end face of the single unit.

[0017] Figure 8 yes Figure 7 A cross-sectional view of the battery package along line b-b.

[0018] Figure 9 This is an enlarged top view showing the main part of the end face of the single cell of the battery package in Embodiment 1.

[0019] Figure 10 yes Figure 9 A cross-sectional view of the end face of the single unit along the d-d line.

[0020] Figure 11 This is an enlarged top view showing the main part of the battery package of Example 1.

[0021] Figure 12 yes Figure 11 A cross-sectional view of the q-q line.

[0022] Figure 13A It means to indicate that in Figure 12 The streamline vector diagram is a simulation result calculated based on the flow velocity of gas discharged from the gas outlet.

[0023] Figure 13B It means to be in Figure 12 The contour map is a simulation result calculated by taking the flow rate of gas discharged from the gas outlet.

[0024] Figure 14 It is a graph showing the pressure change of the released gas according to the overlap area between the lead plate and the gas outlet.

[0025] Figure 15 This is an enlarged top view of the main part of the other single-cell end face of the battery package in Embodiment 1.

[0026] Figure 16 yes Figure 15 A cross-sectional view of the end face of the single unit along the m-m line.

[0027] Figure 17 This is an enlarged top view of the main part of another single-cell end face of the battery package in Embodiment 1.

[0028] Figure 18 This is an enlarged top view showing the main part of the battery package in Embodiment 2.

[0029] Figure 19 This is an enlarged top view showing the main part of the battery package in Embodiment 3.

[0030] Figure 20 This is an enlarged top view showing the main part of the battery package in Embodiment 4. Detailed Implementation

[0031] The method of the present invention can also be determined by the following structure and features.

[0032] In another embodiment of the battery package of the present invention, based on the above embodiment, the secondary battery cell has an electrode on the inner side of the cell end face, the electrode having a smaller outer shape than the cell end face, and the lead plate includes: a fixing piece fixed to the electrode; and a connecting piece connecting the fixing piece, the connecting piece being formed to be narrower than the fixing piece. According to the above structure, it is possible to suppress the area of ​​the connecting piece blocking the gas outlet when the fixing piece of the lead plate is fixed to the electrode.

[0033] Furthermore, in other embodiments of the battery package of the present invention, the width of the connecting piece is made shorter than the length of the gas outlet, based on any of the above embodiments. According to the above structure, even if the gas outlet overlaps with the connecting piece, it is possible to avoid the connecting piece, which is shorter than the gas outlet, completely blocking the gas outlet.

[0034] Furthermore, in other embodiments of the battery package of the present invention, based on any of the above embodiments, the connecting piece is composed of multiple branch pieces, which are configured to support the fixing piece in a spaced manner. According to the above structure, an opening window can be formed in the connecting piece supporting the fixing piece, thus avoiding the situation where the fixing piece extensively blocks the gas outlet.

[0035] Furthermore, in other embodiments of the battery package of the present invention, based on any of the above embodiments, the plurality of branch plates are arranged on the lead plate such that they extend toward the same side relative to the fixed plate. According to the above structure, openings can be formed between the branch plates, allowing gas to escape through these openings.

[0036] Furthermore, in other embodiments of the battery package of the present invention, based on any of the above embodiments, the plurality of branch tabs are disposed on the lead plate such that they extend toward opposite sides relative to the fixed tab. According to the above structure, the opening formed in the lead plate can be made larger.

[0037] Furthermore, in other embodiments of the battery package of the present invention, the shape of the fixing plate is smaller than that of the electrode, based on any of the above embodiments. According to the above structure, the situation where the fixing plate extensively blocks the gas outlets formed around the electrodes is avoided, ensuring the effective opening area of ​​the gas outlets and thus improving safety.

[0038] Furthermore, in addition to any of the above embodiments, the battery package of other embodiments of the present invention also includes a battery retainer for housing the plurality of secondary battery cells, wherein the connecting piece is fixed to the battery retainer by thermal riveting at the fastening connection point.

[0039] Furthermore, in other embodiments of the present invention, the battery package is based on any of the above embodiments, wherein the plurality of gas outlets are arranged in a ring-shaped configuration, separated from each other, on one of the end faces of the cell.

[0040] Furthermore, in other embodiments of the present invention, the battery package is based on any of the above embodiments, wherein the plurality of secondary battery cells have an outer casing that is cylindrical. According to the above structure, even when the rotation direction cannot be specified using cylindrical secondary battery cells, the safety of the battery package can be guaranteed by ensuring that the opening area of ​​each gas outlet is at least 60%.

[0041] Furthermore, in other embodiments of the present invention, the battery package is based on any of the above embodiments, wherein the plurality of gas outlets are respectively arc-shaped openings.

[0042] Furthermore, in other embodiments of the present invention, the plurality of gas outlets are arranged at equal intervals, based on any of the above embodiments.

[0043] Furthermore, in other embodiments of the present invention, the battery package is based on any of the above embodiments, wherein the plurality of gas outlets are arranged in a ring at 120° intervals along the circular shape of the cell end face.

[0044] Furthermore, in addition to any of the above embodiments, the battery package of the present invention also includes a heat-resistant plate disposed on the surface of the lead plate opposite to the plurality of secondary battery cells. According to the above structure, even if high-temperature, high-pressure gas is discharged from the gas outlet of a certain secondary battery cell, safety can be improved by utilizing the heat-resistant plate for protection.

[0045] Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. However, the embodiments shown below are merely illustrative examples to concretize the technical concept of the present invention, and the present invention is not specific to the following content. Furthermore, this specification does not intend to specify the components shown in the patented technical solutions as components of the embodiments. In particular, the dimensions, materials, shapes, and relative arrangements of the constituent components described in the embodiments are not intended to limit the scope of the present invention unless specifically stated therein, and are merely illustrative examples. It should be noted that the size, positional relationships, etc., of the components shown in the various drawings are sometimes exaggerated for clarity. Moreover, in the following description, the same names and reference numerals denote the same or homogeneous components, and detailed descriptions are appropriately omitted. Furthermore, the elements constituting the present invention can be composed of multiple elements from the same component, or one component can perform the functions of multiple elements; conversely, multiple components can share the function of one component.

[0046] The battery package of the present invention is used as a power source for driving mobile devices such as electric trolleys, electric scooters, and electric bicycles. It is also used as a power source for portable electrical devices such as wireless phones, electric cleaners, and power tools. In fixed-location energy storage applications, it can be used as a backup power source for servers, a power supply for homes, businesses, and factories. Furthermore, it can be used as a power source for driving vehicles such as hybrid vehicles and electric motor vehicles. Hereinafter, as an embodiment of the present invention, a battery package used as a driving power source for an electric motorcycle will be described.

[0047] [Implementation Method 1]

[0048] exist Figures 1 to 16 The figure shows a battery package 100 according to Embodiment 1 of the present invention. In these figures, Figure 1 This is a perspective view showing the battery package 100 according to Embodiment 1. Figure 2 yes Figure 1 An exploded perspective view of the battery package 100. Figure 3 yes Figure 2 Exploded perspective view of battery holder 20 Figure 4 It means in Figure 3 An exploded perspective view of the battery holder 20 housing the secondary battery cell 1, with the lead plate 30 connected. Figure 5 This is a top view showing the end face 1a of the secondary battery cell 1. The battery package 100 shown in these figures includes an outer housing 10 and a battery module 2.

[0049] (Outer casing 10)

[0050] The outer casing 10 houses the battery module 2 within its internal storage space. The outer casing 10 can be any shape that accommodates the internal storage space. Figures 1-2 In the example shown, the outer casing 10 is formed as a box shape that extends in one direction. The box-shaped outer casing 10 is divided into an upper casing 11 and a lower casing 12, which are divided into two parts vertically or horizontally. The outer casing 10 is preferably made of a component with excellent insulation properties, such as polycarbonate, PC-ABS alloy, or other resins. Alternatively, it may be made of metal components such as aluminum or its alloys.

[0051] (Battery Module 2)

[0052] The battery module 2 is housed in the internal space inside the outer casing 10. The battery module 2 is also called a core package, and is composed of a battery holder 20 that houses multiple secondary battery cells 1 and a circuit board 3.

[0053] The battery holder 20 is divided into multiple sub-holders 21 and 22, which clamp the secondary battery cell 1. Figure 3 In this example, the battery holder 20 houses and holds multiple cylindrical secondary battery cells 1 in a vertically arranged position. The multiple secondary battery cells 1 are connected in series or parallel via lead plates 30, etc. The number of secondary battery cells can be arbitrarily set according to the required specifications. Figure 3 In the example, 15 secondary battery cells 1 are used in battery module 2, but the structure is not limited to this. Alternatively, multiple battery blocks can be used to construct battery module 2, and multiple secondary battery cells 1 can be housed in each battery block.

[0054] exist Figure 3 In this example, the battery holder 20 is divided into two parts vertically, and the secondary battery cell 1 is stored in a clamping manner from top to bottom using the storage tube 23 divided into two parts. It should be noted that the number of divisions of the battery holder 20 is not limited to 2, and can be 3 or more. In addition, the battery holder 20 can be made of a resin such as polycarbonate with excellent insulation properties.

[0055] In addition, the battery holder 20 is provided with multiple storage tubes 23 for separately storing the individual secondary battery cells 1. Furthermore, as... Figure 3 , Figure 4 As shown in the exploded perspective view, a connection window 24 is provided at the end face of the storage tube 23 so that the end face 1a of the secondary battery cell 1 stored in the storage tube 23 can be connected from the outside of the battery holder 20 to the lead plate 30. The connection window 24 is formed to expose a portion of the end face 1a of the cell. In this example, the connection window 24 is formed in the shape of a bullet or a semi-circle, but is not limited to this shape; it can also be circular or rectangular.

[0056] (Secondary battery cell 1)

[0057] Each secondary battery cell 1 can utilize secondary battery cells with a cylindrical or square shape. Figure 3 In the example shown, the cylindrical secondary battery cells 1 can be arranged in a staggered, longitudinal orientation. It should be noted that the number and configuration of the secondary battery cells 1 are not limited to this example; any number and configuration can be appropriately used. For example, the cylindrical secondary battery cells can also be arranged in a matrix.

[0058] Each secondary battery cell 1 has positive and negative electrodes. The positive and negative electrodes are preferably located on one end face 1a of the secondary battery cell 1. The electrodes are positioned inside the end face 1a such that their external dimensions are smaller than the end face 1a. Known secondary batteries such as lithium-ion batteries, nickel-metal hydride batteries, and nickel-cadmium batteries can be appropriately used in this type of secondary battery cell 1.

[0059] (Gas outlet 1b)

[0060] Furthermore, each of the outer casings of the secondary battery cell 1 is provided with a gas outlet 1b. The gas outlet 1b releases the gas inside the outer casing to the outside when the internal pressure of the outer casing rises. The gas outlet 1b is located on one of the end faces 1a of the secondary battery cell 1. Figure 4 In the example shown, the gas outlet 1b is located on the positive electrode side of the secondary battery cell 1. Alternatively, the gas outlet 1b can also be configured as a gas discharge valve that opens in response to an increase in internal pressure of the outer casing.

[0061] Furthermore, multiple gas outlets 1b can be opened at different locations. Preferably, the multiple gas outlets 1b are arranged in a ring, separated from each other, on one of the monomer end faces 1a. When the gas outlets 1b are opened on a ring-shaped monomer end face 1a, they are preferably formed in a ring shape along the circular shape of the monomer end face 1a. Figure 4 , Figure 5 In the example shown, there are three openings around the positive terminal of the electrode formed on one side of the monomer end face 1a. Each gas outlet 1b is formed as an arc-shaped slit along the circular positive terminal. These gas outlets 1b are arranged at equal intervals. Figure 5 In the example, regarding the line segment connecting the center of the arc shape of each gas outlet 1b to the center of the circular shape of the monomer end face 1a, the angle at which the line segments of adjacent gas outlets 1b intersect each other at the center of the monomer end face 1a is 120°. However, the number and shape of the gas outlets are not limited to this example; for example, there could be two or more.

[0062] (Exhaust port 13 on the shell side)

[0063] On the other hand, the outer casing 10 has a casing-side discharge port 13 formed in part for releasing high-pressure gas to the outside when high-pressure gas is discharged through the gas discharge port 1b of the secondary battery cell 1. Figure 2 In some examples, the housing-side discharge hole 13 is located on the rear side of the lower housing 12 of the outer housing 10. In these examples, the housing-side discharge hole 13 is rectangular, but the shape of the housing-side discharge hole is not limited to a rectangular shape. It can also be octagonal, hexagonal, quadrilateral, or other polygonal shapes, circular shapes, racetrack shapes, elliptical shapes, etc.

[0064] Lead plates 30 are respectively disposed on each end face of the battery holder 20. Alternatively, the battery holder 20 may also be provided with a positioning mechanism on its side for positioning the position where the lead plates 30 are fixed, for example, a guide wall is provided around the lead plates.

[0065] (Circuit board 3)

[0066] like Figure 3 As shown, the battery module 2 is connected to the circuit board 3 via a lead plate 30. The circuit board 3 is equipped with a charge / discharge circuit for charging and discharging the secondary battery cell 1, a protection circuit for monitoring the voltage and temperature of the secondary battery cell 1 and cutting off the current in case of abnormalities, etc. The circuit board 3 is made of glass epoxy board or the like. In addition, a substrate holder can be provided to hold this circuit board 3. The substrate holder can be connected to a battery holder.

[0067] (Leaderboard 30)

[0068] The lead plate 30 connects the electrodes of the end face 1a of the secondary battery cell 1 to each other, and connects multiple secondary battery cells 1 in series and parallel. Figure 3 In the example above, the end faces 1a of 15 secondary battery cells 1 are connected to each other by lead plates 30, and the secondary battery cells 1 are configured as 15 connected in parallel. It should be noted that the number, configuration, series connection, and number of parallel connections of secondary battery cells are not limited to this example, and any number and configuration can be used appropriately.

[0069] exist Figure 3 , Figure 4 In this example, lead plates 30 are respectively disposed on each end face 1a of the secondary battery cell 1. Alternatively, each end face 1a of the cell may be divided into multiple lead plates 30. Each lead plate 30 is formed as a plate and connects the electrodes disposed on the end face 1a of the secondary battery cell 1 to each other. In addition, in order to connect with the electrodes of the secondary battery cell 1, the plate-shaped lead plates 30 have fixing pieces 32 formed at the positions corresponding to the electrodes. Preferably, each fixing piece 32 is cut out around the fixing piece 32 in the lead body 31, which will become the main surface of the plate-shaped lead plate 30, and connected to the lead body 31 by connecting pieces 34, so as to facilitate connection with the electrodes of the secondary battery cell 1. By bending the connecting pieces 34, a structure is achieved in which the fixing pieces 32 are located at a different height from the plate-shaped lead body 31 and are reasonably connected to the electrodes located at a different height from the lead body 31.

[0070] These lead plates 30 are made of metal plates with excellent conductivity, such as aluminum plates or nickel plates. Alternatively, a nickel coating can be applied to the surface of the lead plate 30 as needed. Furthermore, the lead plate 30 is fixed to the end face 1a of the secondary battery cell 1 by laser welding, spot welding, or the like. In particular, projection welding, which involves protrusions on the surface of the fixing plate 32, can be appropriately utilized. Moreover, to improve the tightness of the fit between the fixing plate 32 and the end face 1a of the cell, slits 33 or similar features can be provided to facilitate further deformation.

[0071] [Comparative Example]

[0072] like Figure 6 As shown in the comparative example battery package 600, in a configuration where multiple secondary battery cells 601 are housed in the battery holder 620 with the cell end face 1a exposed from the connection window 624 and fixed by the lead plate 630, the gas outlet 601b formed on the cell end face 601a is as follows: Figure 7 As shown, it is blocked by lead plate 630. In this configuration, it is considered that... Figure 8 As shown, in the event that high-temperature, high-pressure gas is released from a secondary battery cell 601A, the gas is bounced back by the lead plate 630 located on the upper surface of the gas outlet 601b. As a result, the high-temperature, high-pressure gas disperses to the surrounding area, negatively affecting adjacent secondary battery cells 601B. Especially in the case of secondary battery cells 601 with a cylindrical outer canister, it is difficult to determine the rotation direction of the cylinder during the assembly of the battery package. As a result, when... Figure 7 When any of the multiple gas outlets 601b shown is blocked by the lead plate 630, the release of gas from that gas outlet 601b is hindered as described above.

[0073] Therefore, in the battery package 100 of this embodiment, as Figure 9 The shape of the lead plate 30 is modified as shown to ensure that no gas outlet 1b is completely blocked by the lead plate 30. Figure 10 Ensure complete gas venting as shown. In Figure 9 In this example, the lead plate 30 includes: a fixing piece 32 fixed to the electrode; and a connecting piece 34 connecting the fixing piece 32 to the lead body 31. The connecting piece 34 is formed to be narrower than the width of the fixing piece 32. By forming it in this way, it is possible to suppress the area of ​​the connecting piece 34 blocking the gas outlet 1b when the fixing piece 32 of the lead plate 30 is fixed to the electrode.

[0074] It should be noted that the gas discharged from the gas outlet 1b through the connecting window 24 to the outside of the battery holder 20 is guided to the housing-side discharge hole 13 through the gas discharge path defined inside the outer housing 10 and discharged from the battery package 100 to the outside.

[0075] Furthermore, the width WL of the connecting piece 34 is preferably shorter than the length WS of the gas outlet 1b. Therefore, even if the gas outlet 1b overlaps with the connecting piece 34, it is possible to avoid the connecting piece 34, being shorter than the gas outlet 1b, completely blocking the gas outlet 1b.

[0076] The lead plate 30 partially overlaps with the opening area of ​​at least one of the plurality of gas outlets 1b. Especially in the case of a secondary battery cell with a cylindrical outer canister, it is not easy to determine the rotation direction of the cylindrical secondary battery cell when fixing the lead plate to the cell end face during battery package assembly. Therefore, it is fixed to the lead plate with different rotation angles of the cell end face of each secondary battery cell. Thus, it is preferable to design the gas outlet 1b such that regardless of the rotation angle at which each secondary battery cell 1 is fixed to the lead plate 30, each gas outlet 1b ensures that its opening area accounts for more than 60% of the total area.

[0077] The inventors of this application conducted a simulation experiment to investigate the effect of local overlap caused by the lead plate 30 on the opening area of ​​the gas outlet 1b. Here, we consider... Figure 11 The battery package 100 of Embodiment 1 is shown as described. Figure 11 In the diagram, the location of the gas outlet 1b is indicated by a gray coating. A portion of the gas outlet 1b is covered by the lead plate 30. The portion of the gas outlet 1b of each secondary battery cell that is not covered by the lead plate 30, in other words, the portion of the gas outlet 1b exposed from the lead plate 30, constitutes the effective opening area. The structure of the battery package 100 was investigated. Figure 12 The cross-section shown shows the gas velocity as it exits from gas outlet 1b. The results are then... Figure 13A Streamline vector graphics and Figure 13B The contour plot is shown. Additionally, the relationship between the opening rate of gas outlet 1b and the pressure change of the released gas from gas outlet 1b is shown in... Figure 14 As shown in the diagram. The opening rate of gas outlet 1b is the ratio of the area of ​​the lead plate that does not overlap with the opening area of ​​at least one of the plurality of gas outlets to the opening area of ​​gas outlet 1b. Figure 14 As shown, it is believed that the pressure is low when the opening ratio is 60% or higher, allowing almost all the gas to be released. On the other hand, it is believed that in areas with a lower opening ratio, the pressure change is less, resulting in resistance from the lead plate 30 and insufficient gas discharge. Based on the above, it is desirable to design the lead plate 30 such that the opening area of ​​the gas outlet 1b is ensured to be 60% or higher. This avoids obstruction of gas discharge by the lead plate 30, promoting smooth gas discharge. Furthermore, it prevents the dispersion of high-temperature, high-pressure gas in the surrounding secondary battery cells 1, thus preventing burn-out and improving the safety of the battery package 100.

[0078] Furthermore, it is preferable to design the gas outlet 1b such that even when the rotation angle of the cylindrical secondary battery cell 1's end face 1a changes, the opening area of ​​each gas outlet 1b remains at 60%. For example, in Figure 15In, it means from Figure 9 An example of a lead plate 30 fixed in a state where it has rotated 180°. In this state, in the gas outlet 1b located at the top, as shown... Figure 16 As shown in the cross-sectional view, the lead plates 30 are almost completely overlapped, ensuring a large opening area. Additionally, in Figure 17 China indicates that it is from Figure 16 The example shows a lead plate 30 fixed in a position where it has been rotated 90° clockwise. In this state, each of the gas outlets 1b also has a sufficient opening area, so that even if gas is being discharged, it can be prevented from being obstructed by the lead plate 30.

[0079] [Implementation Method 2]

[0080] The above Embodiment 1 illustrates an example of forming a connecting piece 34 that connects the fixing piece 32. The present invention is not limited to this structure; multiple branch pieces can also be used to form the connecting piece. This example is taken as the battery package 200 of Embodiment 2 and... Figure 18 The figures are indicated in the figure. In this figure, the same reference numerals are used for components that are the same as those in Embodiment 1 described above, and detailed descriptions are omitted as appropriate.

[0081] exist Figure 18 In the battery package 200, a pair of branch tabs 35 form a connecting tab 34B for the lead plate 30B. The pair of branch tabs 35 connect the fixing tab 32B to the lead body 31B, resulting in a window-like opening in the area surrounded by the fixing tab 32B, the pair of branch tabs 35, and the lead body 31B. By forming an opening window 36 in the connecting tab 34B that connects the fixing tab 32B and the lead body 31B, regardless of the rotation angle at which each secondary battery cell 1 is fixed to the lead plate 30, the area covered by the connecting tab 34B in the overall area of ​​each gas outlet 1b's opening region is set to less than 40%, and the area not covered by the connecting tab 34B is set to more than 60%, thus preventing the fixing tab 32B from blocking a large area of ​​the gas outlet 1b.

[0082] [Implementation Method 3]

[0083] In the above-described embodiment 2, it was described that a plurality of branch pieces 35 extend relative to the fixing piece 32 from the end edge of the connection window 24 on the same side of the lead plate 30B. Figure 18 In this example, the multiple branch pieces 35 extend downward relative to the fixed piece 32. However, the present invention is not limited to this structure, and the multiple branch pieces may extend to different sides relative to the fixed piece. This example is used as the battery package 300 in Embodiment 3. Figure 19The same reference numerals are used to indicate components that are the same as those in Embodiment 1 described above, and detailed descriptions are omitted where appropriate.

[0084] exist Figure 19 In the battery package 300 shown, branch tabs 35C are respectively disposed on opposite sides (left and right in the figure) of the fixing tab 32C. This structure allows for a more efficient formation of the opening 36C in the lead body 31C of the lead plate 30C compared to... Figure 18 Larger size allows for a larger opening of the gas outlet 1b.

[0085] [Implementation Method 4]

[0086] Alternatively, the shape of the fixing plate can be made smaller than the shape of the electrode. This example is used as the battery package 400 in Embodiment 4. Figure 20 The same reference numerals are used to indicate components that are the same as those in Embodiment 1 described above, and detailed descriptions are omitted where appropriate.

[0087] exist Figure 20 In the battery package 400 shown, the shape of the retaining plate 32D is formed to converge to the size of a circle that serves as the positive terminal of the electrode. By adopting this structure, the situation where the retaining plate 32D extensively blocks the gas outlet 1b formed around the electrode is avoided, and the effective opening area of ​​the gas outlet 1b can be expected to be ensured, thereby improving safety.

[0088] Alternatively, the lead plate can be partially fixed to the battery holder. Figure 20 In this example, a portion of the connecting piece 34D or the lead body 31D is fixed to the battery holder 20D at the fastening connection point 40 by heat riveting. By directly fixing the lead plate 30D locally to the battery holder 20D in this way, the lead plate 30D is stably fixed, and it is expected that the safety effect will be improved by specifying the gas release path according to the intended plan even when gas is released.

[0089] (Heat-resistant plate 50)

[0090] Alternatively, a heat-resistant plate 50 can be sandwiched between the lead plate 30 and the inner surface of the outer casing 10. Figure 2 , Figure 3In the example shown, the heat-resistant plate 50 is formed to cover the entire surface of the lead plate 30. By configuring the heat-resistant plate 50 on the end face of the battery holder 20 and covering the end face 1a of the cell where the gas outlet 1b is provided, even if high-temperature and high-pressure gas is discharged from the gas outlet 1b of a secondary battery cell 1, the impact resistance is improved and the gas does not immediately escape from the battery enclosure, thus preventing the flame generated by the igniting gas from leaking directly to the outside of the battery enclosure. This heat-resistant plate 50 is made of a material with excellent insulation and fire resistance, such as mica. Alternatively, the heat-resistant plate 50 can be disposed between the surface of the battery holder 20 and the inner surface of the outer casing 10. Figure 7 In the example shown, the heat-resistant plate 50 is formed to cover the entire surface of the first cell end face 1a1 of the secondary battery cell 1. This heat-resistant plate 50 can be made of a material with excellent insulation and fire resistance, such as mica.

[0091] It should be noted that, in the above embodiments, for the sake of simplicity, the example shown is that only the positive terminal of the secondary battery cell 1 is connected to the lead plate 30. However, the present invention is not limited to this structure, and it goes without saying that it is also possible to configure a structure in which both the positive and negative terminals are connected to a single lead plate. In the case of a secondary battery cell 1 in which one of the end faces 1a of the cylindrical outer can is set as the positive terminal and the other as the negative terminal, in the case where a gas outlet 1b is provided only on the positive terminal and no gas outlet 1b is provided on the negative terminal side, the fixing piece 32 and its connecting piece 34 connected to such a negative terminal are not limited to the above-described manner, and other methods can be used, for example, by making the connecting piece thicker.

[0092] Furthermore, a protective sheet can be disposed between the surface of the battery holder 20 and the inner surface of the outer casing 10 as needed. For example, the protective sheet can be disposed such that it covers the end face 1a of the cell where the gas outlet 1b is provided. By using a protective sheet that improves impact resistance and other properties by covering the battery holder 20, the end face 1a of the cell where the gas outlet 1b is provided is covered. Thus, even if high-temperature and high-pressure gas is discharged from the gas outlet 1b of a secondary battery cell 1, it will not be immediately discharged from the packaged battery, and the situation where the flame generated by the ignition gas leaks directly to the outside of the packaged battery can be avoided.

[0093] In the examples above, an example of using a battery package as a power source for an electric scooter was described. However, the present invention is not limited to this, and the battery package can also be fitted into an electrical device that is driven, for other purposes of powering the electrical device. Examples of electrical devices include electric vehicles, electric carts, and other mobile or portable electrical devices. In such electrical devices, when the remaining capacity of the battery package is low or the battery package deteriorates over time, the battery package can be replaced and the electrical device can continue to be used. However, the present invention is not limited to a replaceable battery package that mainly houses secondary battery cells; it can also be applied to a scheme in which secondary battery cells are housed within the casing of an electrical device. In the present invention, it is sufficient for the battery package to house only secondary battery cells within the casing; a structure in which secondary battery cells for driving are built into the casing of the electrical device itself is also included in the battery package. That is, the present invention is not limited to replaceable battery packages, and can also be applied to electrical devices that house secondary battery cells.

[0094] Industrial applicability

[0095] The battery package of the present invention can be appropriately used as a power source for driving mobile devices such as electric scooters, electric carts, and electric bicycles. It can also be appropriately used as a power source for portable electrical devices such as wireless devices, electric cleaners, and power tools. Alternatively, it can be appropriately used as a backup power source for servers, or as a fixed-installation energy storage device for home, office, or factory use.

[0096] Explanation of reference numerals in the attached figures

[0097] 100, 200, 300, 400 battery packages

[0098] 1. Secondary battery cell

[0099] 1a Monomer end face

[0100] 1b Gas exhaust outlet

[0101] 2 Battery Modules

[0102] 3 Circuit board

[0103] 10. External housing

[0104] 11. Upper shell

[0105] 12 Lower shell

[0106] 13. Exhaust port on the casing side

[0107] 20, 20D Battery Retaining Components

[0108] 21 sets of retaining components

[0109] 22 sets of retaining components

[0110] 23 Storage Cylinders

[0111] 24 Connecting Windows

[0112] 30, 30B, 30C, 30D lead plates

[0113] 31, 31B, 31C, 31D Lead body

[0114] 32, 32B, 32C, 32D fixing plates

[0115] 33 Slits

[0116] Connecting pieces 34, 34B, 34C, and 34D

[0117] 35, 35C branch chips

[0118] 36, 36C Opening window

[0119] 40 Fastening connection points

[0120] 50 heat-resistant plate

[0121] 52 Electrode Window

[0122] 600 battery package

[0123] 601, 601A, 601B secondary battery cells

[0124] 601a Single-unit end face

[0125] 601b Gas Exhaust Port

[0126] 620 Battery Retainer

[0127] 624 Connecting Window

[0128] 630 leadboard

[0129] The width of WL connecting piece 34

[0130] WS is the length of the gas outlet.

Claims

1. A battery package comprising: Multiple secondary battery cells, each having multiple gas outlets (multiple 1b) on one of the cell end faces (1a) that open in response to an increase in internal pressure. A lead plate that connects the end faces of the plurality of secondary battery cells to each other; and The outer casing houses the plurality of secondary battery cells connected by the lead plate. in, With the lead plate fixed to the end face of the unit in a manner that partially overlaps with the opening area of ​​at least one of the plurality of gas outlets when viewed perpendicularly relative to the end face of the unit, each of the plurality of gas outlets satisfies the following condition: the area covered by the lead plate in the opening area of ​​at least one of the plurality of gas outlets is less than 40% of the opening area of ​​each gas outlet.

2. The battery package according to claim 1, wherein, The secondary battery cell has an electrode located inside the cell's end face, which is smaller in shape than the cell's end face. The lead plate includes: A fixing plate, which is fixed to the electrode; and Connecting piece, which connects the fixing piece, The connecting piece is narrower than the fixing piece.

3. The battery package according to claim 2, wherein, The width of the connecting piece is shorter than the length of the gas outlet.

4. The battery package according to claim 2, wherein, The connecting piece is composed of multiple branch pieces. The plurality of branch plates support the fixed plate separately.

5. The battery package according to claim 4, wherein, The plurality of branch plates are arranged on the lead plate in such a way that they extend from the fixed plate toward the same side.

6. The battery package according to claim 4, wherein, The plurality of branch plates are disposed on the lead plate such that they extend from opposite sides relative to the fixed plate.

7. The battery package according to claim 2, wherein, The shape of the fixing plate is smaller than that of the electrode.

8. The battery package according to claim 2, wherein, The battery package also includes a battery retainer for housing the plurality of secondary battery cells. The connecting piece is fixed to the battery holder by heat riveting at the fastening connection point.

9. The battery package according to any one of claims 1 to 8, wherein, The plurality of gas outlets are arranged in a ring-shaped configuration, separated from each other on one of the end faces of the unit.

10. The battery package according to any one of claims 1 to 8, wherein, The multiple secondary battery cells have cylindrical outer cans.

11. The battery package according to claim 10, wherein, The plurality of gas outlets are each arc-shaped opening.

12. The battery package according to claim 10, wherein, The plurality of gas outlets are arranged at equal intervals.

13. The battery package according to claim 12, wherein, The plurality of gas outlets are arranged in a ring at 120° intervals along the circular shape of the end face of the unit.

14. The battery package according to any one of claims 1 to 8, wherein, The battery package also includes a heat-resistant plate disposed on the side of the lead plate opposite to the plurality of secondary battery cells.

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