Battery and method of manufacturing the same

Abstract

This invention relates to a battery and a method for manufacturing the same. The battery (1) comprises: an electrode body (200) and an electrolyte (200A); an outer can (100) having an injection hole (121); and a sealing member (900) fixed to the outer can by a slit. The sealing member includes: a first member (910) having a shaft portion (912); and a second member (920) having a engaging portion (921) that engages with the shaft portion. The shaft portion has: an abutting surface (912A) for the engaging portion to abut against; and a slit fixing portion (912B) formed between the inner surface (120A) of the outer can and the engaging portion (921), fixing the sealing member (900) to the outer can (100). The thickness A of the portion forming the injection hole (121) in the outer container and the distance B between the contact surface (912A) of the shaft portion (912) and the inner surface of the outer container (100) satisfy the relationship 0.55≤B / A.

Description

Technical Field

[0001] This technology relates to batteries and their manufacturing methods. Background Technology

[0002] Conventional methods employ a structure in which the electrolyte injection port is sealed by a sealing component after the electrolyte is injected into the outer casing of the battery. Such a structure is described, for example, in Japanese Patent Application Publication No. 2019-44928. In the structure described in Japanese Patent Application Publication No. 2019-44928, the sealing component is fixed to the outer casing by a swaging mechanism. Summary of the Invention

[0003] When the sealing component is fixed to the outer can by a slit, a stable sealing state is required to ensure the airtightness of the outer can. The purpose of this technology is to provide a battery and a method for manufacturing the same that can maintain a stable sealing state through the sealing component to the electrolyte injection port.

[0004] The battery involved in this technology comprises: an electrode body and an electrolyte; an outer can, including an outer surface and an inner surface, for housing the electrode body and the electrolyte, and having an injection hole extending from the outer surface to the inner surface; and a sealing component, which is fixed to the outer can by a slit to seal the injection hole. The sealing component includes: a first component having a shaft portion that is inserted into the injection hole; and a second component having a engaging portion that engages with the shaft portion. The shaft portion has: an abutment surface for the engaging portion to abut against; and a slit fixing portion formed between the inner surface of the outer can and the engaging portion, fixing the sealing component to the outer can. The thickness (A) of the portion forming the injection hole in the outer can and the distance (B) between the abutment surface of the shaft portion and the inner surface of the outer can satisfy the relationship 0.55 ≤ B / A.

[0005] The battery manufacturing method of this technology includes: a step of housing an electrode body in an outer can; a step of injecting electrolyte into the interior of the outer can through an injection port provided in the outer can; and a step of sealing the injection port by a sealing member. The sealing step includes: preparing a first member having a shaft portion and a second member having a locking portion that engages with the shaft portion; inserting the shaft portion into the injection port; and bringing the locking portion of the second member into contact with the abutting surface formed on the shaft portion of the first member, and compressing the shaft portion by the locking portion, thereby forming a slit fixing portion on the shaft portion located between the inner surface of the outer can and the locking portion. The thickness (A) of the portion in the outer can where the injection port is formed and the distance (C) between the abutting surface of the shaft portion and the inner surface of the outer can before the slit fixing portion is formed satisfy the relationship 1.37 ≤ C / A.

[0006] The above and other objects, features, aspects, and advantages of the invention become clear from the following detailed description in connection with the invention and the accompanying drawings. Attached Figure Description

[0007] Figure 1 It is a 3D diagram of a square secondary battery.

[0008] Figure 2 yes Figure 1 Sectional view II-II in the diagram.

[0009] Figure 3 This is a cross-sectional view showing the structure of a sealing component according to one embodiment.

[0010] Figure 4 This is a cross-sectional view showing the construction of the sealing component involved in the comparative example.

[0011] Figure 5 This is a cross-sectional view showing the structure of the sealing component before the joint is fixed according to one embodiment.

[0012] Figure 6 This is a cross-sectional view showing the structure of the sealing component involved in the comparative example before the joint is fixed.

[0013] Figures 7A to 7D This diagram illustrates the electrolyte injection process and the sealing component closure process.

[0014] Figures 8A to 8C This is a cross-sectional view showing the seam-sealing process of the sealing component according to one embodiment.

[0015] Figures 9A to 9C This is a cross-sectional view showing the seam-sealing process of the sealing component involved in the comparative example. Detailed Implementation

[0016] The following describes the implementation of this technology. Note that some identical or equivalent parts may be labeled with the same reference numerals in the accompanying drawings without being described again.

[0017] Furthermore, when the number, quantity, etc., are mentioned in the embodiments described below, the scope of this technology is not necessarily limited to that number, quantity, etc., unless specifically stated otherwise. Additionally, in the embodiments described below, each constituent element is not necessarily essential to this technology, unless specifically stated otherwise.

[0018] Furthermore, in this specification, the terms "comprise," "include," and "have" are open-ended. That is, when a structure is included, other structures besides that structure may be included, or other structures besides that structure may not be included. Additionally, this technology is not limited to necessarily achieving all the effects described in this embodiment.

[0019] The battery involved in this embodiment is typically a lithium-ion secondary battery for automotive use. However, in this specification, "battery" is not limited to lithium-ion batteries and may include other batteries such as nickel-metal hydride batteries.

[0020] Figure 1 This is a 3D view of a square secondary battery 1. Figure 2 yes Figure 1 Sectional view II-II in the diagram.

[0021] like Figure 1 , Figure 2 As shown, the square secondary battery 1 includes a battery casing 100, an electrode body 200, an insulating sheet 300, a positive terminal 400, a negative terminal 500, a positive current collector 600, a negative current collector 700, a cover component 800, and a sealing component 900.

[0022] The battery casing 100 consists of a square outer body 110 with an opening and a bottomed rectangular tube shape, and a sealing plate 120 that seals the opening of the square outer body 110. Preferably, the square outer body 110 and the sealing plate 120 are made of metal, and more preferably aluminum or aluminum alloy.

[0023] An electrolyte injection hole 121 is provided on the sealing plate 120. After the electrolyte is injected into the battery casing 100 through the electrolyte injection hole 121, the electrolyte injection hole 121 is sealed by the sealing component 900 (rivet).

[0024] A gas discharge valve 122 is provided on the sealing plate 120. When the pressure inside the battery casing 100 reaches a predetermined value, the gas discharge valve 122 breaks. As a result, the gas inside the battery casing 100 is discharged to the outside of the battery casing 100.

[0025] The electrode body 200 and the electrolyte are housed together within the battery casing 100. The electrode body 200 is a component formed by stacking a positive electrode plate and a negative electrode plate separated by a separator. A resin insulating sheet 300 is disposed between the electrode body 200 and the square outer casing 110.

[0026] A positive electrode tab 210A and a negative electrode tab 210B are provided at the end of the electrode body 200 on the sealing plate 120 side.

[0027] The positive electrode tab 210A and the positive terminal 400 are electrically connected via the positive current collector 600. The positive current collector 600 includes a first positive current collector 610 and a second positive current collector 620. Alternatively, the positive current collector 600 may be a single component. Preferably, the positive current collector 600 is made of metal, more preferably of aluminum or an aluminum alloy.

[0028] The negative electrode tab 210B is electrically connected to the negative terminal 500 via the negative electrode current collector 700. The negative electrode current collector 700 includes a first negative electrode current collector 710 and a second negative electrode current collector 720. Alternatively, the negative electrode current collector 700 may be a single component. Preferably, the negative electrode current collector 700 is made of metal, more preferably of copper or a copper alloy.

[0029] The positive terminal 400 is fixed to the sealing plate 120 via an external resin insulating member 410. The negative terminal 500 is fixed to the sealing plate 120 via an external resin insulating member 510.

[0030] The positive terminal 400 is preferably made of metal, more preferably of aluminum or an aluminum alloy. The negative terminal 500 is preferably made of metal, more preferably of copper or a copper alloy. The negative terminal 500 may have a region made of copper or a copper alloy disposed on the inner side of the battery casing 100 and a region made of aluminum or an aluminum alloy disposed on the outer side of the battery casing 100.

[0031] The cover component 800 is located between the first positive current collector 610 and the electrode body 200. The cover component 800 may also be provided on the negative current collector side. In addition, the cover component 800 is not a necessary component and can be omitted appropriately.

[0032] In manufacturing the square secondary battery 1, the positive terminal 400, negative terminal 500, positive current collector 600, negative current collector 700, and cover component 800 are assembled onto the sealing plate 120. Meanwhile, the electrode body 200 is surrounded by an insulating sheet 300. The electrode body 200 and the insulating sheet 300 are inserted into the square outer casing 110. Then, the sealing plate 120 is welded to the square outer casing 110, sealing the opening of the square outer casing 110 to form a sealed battery casing 100.

[0033] Then, a non-aqueous electrolyte is injected into the battery casing 100 through the electrolyte injection hole 121 provided on the sealing plate 120. As a non-aqueous electrolyte, for example, a non-aqueous electrolyte containing ethylene carbonate (EC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), and dimethyl carbonate (DMC) can be used.

[0034] After the non-aqueous electrolyte is injected, the electrolyte injection hole 121 is sealed by the sealing component 900 through a pressure reduction process within the battery casing 100. Through the implementation of the above processes, the square secondary battery 1 is completed.

[0035] Figure 3 This is a cross-sectional view showing the structure of the sealing component 900 according to this embodiment. For example... Figure 3 As shown, the sealing component 900 includes a first component 910, a second component 920, and a third component 930.

[0036] The first component 910 (sleeve) is typically made of metal, but is not limited to this. The first component 910 includes a flange portion 911 and a shaft portion 912.

[0037] The flange portion 911 is opposite to the outer surface 120B of the sealing plate 120. The flange portion 911 is located radially outside the shaft portion 912 on the outside of the battery casing 100.

[0038] The shaft portion 912 is inserted into the electrolyte injection hole 121. The shaft portion 912 has: an abutment surface 912A for the second component 920 to abut against; and a seam fixing portion 912B located between the inner surface 120A of the battery casing 100 and the abutment surface 912A. The sealing component 900, including the first component 910, is fixed to the sealing plate 120 by the seam fixing portion 912B.

[0039] The second component 920 (mandrel) is typically made of metal, but is not limited to this. The second component 920 includes an engaging portion 921 and a cutting portion 922.

[0040] The engaging portion 921 abuts against the contact surface 912A of the first component 910. Thus, the second component 920 engages with the shaft portion 912 of the first component 910. The cutting portion 922 is the part of the second component 920 that is cut off during the process of forming the slit fixing portion 912B. By pre-setting a weak point on the second component 920, the position of the cutting portion 922 can be determined.

[0041] The third component 930 (gasket) is made of a material (e.g., resin) with a lower hardness than the first component 910. The third component 930 is compressed between the flange portion 911 of the first component 910 and the outer surface 120B of the sealing plate 120. Thus, the flange portion 911 and the outer surface 120B of the sealing plate 120 can be sealed by the third component 930.

[0042] The thickness (A) of the sealing plate 120 is, for example, about 1.0 mm to 3.0 mm. The distance (B) between the abutting surface 912A of the first component 910 and the inner surface 120A of the sealing plate 120 is set to satisfy the relationship 0.55 ≤ B / A.

[0043] exist Figure 3 In the example shown, the thickness (A) of the sealing plate 120 is 1.17 mm, and the distance (B) between the abutting surface 912A of the first component 910 and the inner surface 120A of the sealing plate 120 is 0.71 mm. Therefore, B / A = 0.61.

[0044] Figure 4 This is a cross-sectional view showing the construction of the sealing component 900 involved in the comparative example. Figure 4In the comparative example shown, the basic construction is also similar to... Figure 3 The construction shown is the same. However, in Figure 4 In the example shown, the thickness (A) of the sealing plate 120 is 1.08 mm, and the distance (B) between the abutting surface 912A of the first component 910 and the inner surface 120A of the sealing plate 120 is 0.33 mm. Therefore, B / A = 0.31.

[0045] Thus, in this embodiment, the sealing component 900 ( Figure 3 In the comparative example, the sealing component 900 ( Figure 4 Compared to the first component 910, the ratio (B / A) of the distance (B) between the contact surface 912A of the first component 910 and the inner surface 120A of the sealing plate 120 to the thickness (A) of the sealing plate 120 is higher. Specifically, in Figure 3 In the construction, since B / A = 0.61, the relationship 0.55 ≤ B / A is satisfied. Figure 4 In the construction, since B / A = 0.31, the relationship 0.55 ≤ B / A is not satisfied.

[0046] According to the sealing component 900 involved in this embodiment ( Figure 3 This allows the shape of the seam fixing portion 912B formed between the abutment surface 912A of the first component 910 and the inner surface 120A of the sealing plate 120 to be stable, maintaining a stable sealing state of the electrolyte injection hole 121 through the sealing component 900.

[0047] Figure 5 This is a cross-sectional view showing the structure of the sealing component 900 according to this embodiment before the joint is fixed. Figure 5 As shown, the shaft portion 912, without the slit fixing portion 912B, is inserted into the electrolyte injection hole 121. The engaging portion 921 of the second component 920 abuts against the contact surface 912A of the shaft portion 912. From Figure 5 When the second component 920 is lifted from the state shown, the shaft portion 912 is compressed by the engaging portion 921, thereby forming the slit fixing portion 912B.

[0048] exist Figure 5 In the state shown, the distance (C) between the contact surface 912A of the first component 910 and the inner surface 120A of the sealing plate 120 is set to a range that satisfies the relationship 1.37≤C / A.

[0049] exist Figure 5 In the example shown, the thickness (A) of the sealing plate 120 is 1.00 mm, and the distance (C) between the abutting surface 912A of the first component 910 and the inner surface 120A of the sealing plate 120 is 1.76 mm. Therefore, C / A = 1.76.

[0050] Figure 6 This is a cross-sectional view showing the structure of the sealing component 900 involved in the comparative example before the joint is fixed. Figure 6 In the comparative example shown, the basic construction is also similar to... Figure 5 The construction shown is the same. However, in Figure 6 In the example shown, the thickness (A) of the sealing plate 120 is 1.50 mm, and the distance (C) between the abutting surface 912A of the first component 910 and the inner surface 120A of the sealing plate 120 is 1.29 mm. Therefore, C / A = 0.86.

[0051] Thus, the sealing component 900 before the seam fixing involved in this embodiment ( Figure 5 In the comparative example, the sealing component 900 before the seam is fixed is similar to that involved in the seam-sealing method. Figure 6 Compared to the first component 910, the ratio (C / A) of the distance (C) between the contact surface 912A of the first component 910 and the inner surface 120A of the sealing plate 120 to the thickness (A) of the sealing plate 120 is higher. Specifically, in Figure 5 In the construction, since C / A = 1.76, the relationship 1.37 ≤ C / A is satisfied. Figure 6 In the construction, since C / A = 0.86, the relationship 1.37 ≤ C / A is not satisfied.

[0052] According to this embodiment, the sealing component 900 before the seam is fixed ( Figure 5 Because the distance between the shaft portion 912 located between the abutment surface 912A of the first component 910 and the inner surface 120A of the sealing plate 120 is set to be large, the buckling margin of the shaft portion 912 during the seam-sealing process is large. As a result, the shape of the seam-sealing fixing portion 912B formed between the abutment surface 912A of the first component 910 and the inner surface 120A of the sealing plate 120 can be stabilized, maintaining a stable sealing state of the electrolyte injection hole 121 through the sealing member 900.

[0053] Figures 7A to 7D This diagram illustrates the electrolyte injection process and the joint sealing process of the plugging components. (For example...) Figure 7A As shown, electrolyte 200A is injected into the battery casing 100 using the injection nozzle 10 (injection process).

[0054] After the electrolyte 200A injection process, the sealing component 900 undergoes a seam-sealing process. For example... Figure 7B As shown, the sealing component 900 is assembled onto the sealing plate 120. At this time, the first component 910 of the sealing component 900 is inserted into the battery casing 100 of the sealing plate 120. A seam clamp 20 is provided on the sealing component 900.

[0055] The seam-closing clamp 20 includes a jaw 21, a head 22, and a pressing part 23. For example... Figure 7C As shown, the second component 920 of the sealing component 900 is held by the gripper 21 provided in the head 22. From this state, the gripper 21 is lifted upwards towards the upper side of the figure. Thus, as... Figure 7D As shown, the first component 910 is fixed to the sealing plate 120 by a slit, and the second component 920 is cut off inside the first component 910. The first component 910 is pressed down toward the lower side of the figure by the pressing part 23. As a result, the third component 930 is pressed down, and the first component 910 and the sealing plate 120 are sealed by the third component 930.

[0056] Figures 8A to 8C This is a cross-sectional view showing the seam-sealing process of the sealing component involved in this embodiment. For example... Figure 8A As shown, the shaft portion 912 of the first component 910 is inserted into the electrolyte injection hole 121.

[0057] Next, as Figure 8B As shown, by lifting the second component 920, a portion of the shaft portion 912 is bent to form a slit fixing portion 912B. In this embodiment, since the bending margin of the shaft portion 912 is ensured to be large as described above, sufficient slit fixing portions 912B can be formed even if the movement of the second component 920 is small. Therefore, the formed slit fixing portion 912B can be prevented from entering the interior of the electrolyte injection hole 121.

[0058] After the seam fixing part 912B is formed, as Figure 8C As shown, the first component 910 is pressed downwards, and the third component 930 is compressed. Since the slit fixing part 912B can be prevented from entering the electrolyte injection hole 121 as described above, the deformation of the sealing plate 120 can be suppressed when the first component 910 is pressed downwards (arrow F1).

[0059] Figures 9A to 9C This is a cross-sectional view showing the seam-sealing process of the sealing component involved in the comparative example. Figures 9A to 9C In the comparative example shown, the basic process is also the same as... Figures 8A to 8C The procedures shown are the same. However, in Figures 9A to 9C In the example shown, because the bending margin of the shaft portion 912 is small, the amount of movement of the second component 920 needs to be increased in order to form a seam fixing portion 912B with the required seam fixing strength. Therefore, the formed seam fixing portion 912B easily enters the interior of the electrolyte injection hole 121. As a result, when the first component 910 is pressed downwards (arrow F1), a downward force (arrow F2) easily acts on the sealing plate 120, causing the sealing plate 120 to easily deform.

[0060] According to the sealing member 900 of this embodiment, since the bending margin of the shaft portion 912 of the first member 910 is large, the entry of the seam fixing portion 912B into the electrolyte injection hole 121 can be suppressed, thus preventing deformation of the sealing plate 120. In other words, the third member 930 can be sufficiently compressed while suppressing deformation of the sealing plate 120 to improve sealing performance. As a result, a stable sealing state of the electrolyte injection hole 121 by the sealing member 900 can be maintained.

[0061] Embodiments of the present invention have been described, but it should be considered that the embodiments disclosed herein are illustrative rather than restrictive in all respects. The scope of the invention is shown by the technical solutions and is intended to include all equivalents and modifications within the scope of the technical solutions.

Claims

1. A battery, characterized by, have: Electrode body and electrolyte; An outer can, including an outer surface and an inner surface, houses the electrode body and the electrolyte, and has an injection hole extending from the outer surface to the inner surface; as well as The sealing component is fixed to the outer can by a slit to seal the injection port. The sealing component includes: The first component has a shaft portion that is inserted into the injection hole; and The second component has an engaging portion that engages with the shaft portion. The shaft portion has: an abutment surface for the engaging portion to abut against; and a seam-fixing portion formed between the inner surface of the outer can and the engaging portion, for fixing the sealing component to the outer can. The thickness A of the portion forming the injection hole in the outer can and the distance B between the abutting surface of the shaft and the inner surface of the outer can satisfy the relationship 0.55 ≤ B / A.

2. The battery according to claim 1, characterized in that, The first component also has a flange portion located radially outward of the shaft portion on the outer side of the outer can. The sealing component also includes a third component that seals between the flange and the outer surface of the outer can.

3. The battery according to claim 1 or 2, characterized in that, The thickness A of the portion forming the injection hole in the outer can is more than 1.0 mm and less than 3.0 mm.

4. The battery according to claim 1 or 2, characterized in that, The outer can includes: a main body having an opening for receiving the electrode body; and a sealing plate, which is combined with the main body. The injection hole is formed in the sealing plate.

5. The battery according to claim 1 or 2, characterized in that, The outer can has a square shape.

6. A method of manufacturing a battery, characterized by, have: The process of storing the electrode body in the outer packaging can; The process of injecting electrolyte into the interior of the outer tank through an injection port provided in the outer tank; as well as The process of sealing the injection hole using a sealing component. The sealing process includes: Prepare a first component having a shaft portion and a second component having a engaging portion that engages with the shaft portion; Insert the shaft into the injection hole; and By abutting the engaging portion of the second component against the abutting surface of the shaft portion formed on the first component, and by compressing the shaft portion using the engaging portion, a constricted groove fixing portion is formed on the shaft portion located between the inner surface of the outer can and the engaging portion. The thickness A of the portion forming the injection hole in the outer can and the distance C between the abutting surface of the shaft portion and the inner surface of the outer can in the state before the formation of the slit fixing portion satisfy the relationship 1.37≤C / A.

7. The method for manufacturing a battery according to claim 6, characterized in that, The first component also has a flange portion located radially outward of the shaft portion on the outer side of the outer can. The sealing process also includes: A third component is disposed between the flange and the outer surface of the outer can; and The flange is pressed toward the third component, thereby sealing the flange with the outer surface of the outer can.

8. The method for manufacturing a battery according to claim 6 or 7, characterized in that, The thickness A of the portion forming the injection hole in the outer can is more than 1.0 mm and less than 3.0 mm.

9. The method for manufacturing a battery according to claim 6 or 7, characterized in that, The process of housing the electrode body in the outer packaging can includes: Prepare the main body and the sealing plate that is attached to the main body; The electrode body is housed within the main body through an opening in the main body; and Combine the sealing plate with the main body. The injection hole is formed in the sealing plate.

10. The method for manufacturing a battery according to claim 6 or 7, characterized in that, The outer can has a square shape.

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