Apparatus for manufacturing cylindrical battery, and cylindrical battery

Abstract

The utility model provides a kind of manufacturing device of cylindrical battery, and cylindrical battery, the manufacturing device of cylindrical battery sequentially has from the upstream side to the downstream side of production line: the group formation unit that group is wound into by positive electrode and negative electrode via diaphragm;Group insertion unit, the metal shell with one end opening is inserted into the group;Bottom spot welding unit, electrode stick is inserted into the central hole of the group from above until group bottom, and welding is carried out;Liquid injection unit, electrolyte is injected into the metal shell;And sealing unit, the opening of the metal shell is sealed, characterized in that, between the group formation unit and the group insertion unit, it is also equipped with the central rod insertion unit that hollow tubular central rod is inserted in the central hole of the group.

Description

Technical Field

[0001] This utility model relates to a manufacturing apparatus for a cylindrical battery, and a cylindrical battery. Background Technology

[0002] Lithium metal batteries are a common type of cylindrical battery. Their manufacturing process typically includes: a grouping process of winding positive and negative electrodes and a separator into a group; a group insertion process of inserting the group into a metal casing with an opening at one end; a bottom spot welding process of inserting electrode rods into the bottom through the central hole at the top of the group and welding them; an electrolyte injection process of injecting electrolyte into the metal casing; and a sealing process of sealing the opening of the metal casing.

[0003] Correspondingly, the manufacturing apparatus for cylindrical batteries typically includes: a group forming unit for winding the positive and negative electrodes into a group via a separator; a group insertion unit for inserting the group into a metal casing with an opening at one end; a bottom spot welding unit for inserting and welding electrode rods from a central hole above the group into the bottom of the group; an electrolyte injection unit for injecting electrolyte into the metal casing; and a sealing unit for sealing the opening of the metal casing.

[0004] The problem with the existing technology is that during the fabrication of group constituent units or the insertion of group insertion units, such as... Figure 4 As shown, wrinkles may form on the inner wall of the central hole (10) on the inner side of group (7). This may cause the electrode rod (9) to directly contact the diaphragm or electrode plate located on the inner wall of the central hole (10) when the electrode rod (9) is inserted into the central hole (10) of group (7) during the bottom spot welding process. This could lead to diaphragm rupture or poor contact between the electrode rod (9) and the bottom of the metal shell, resulting in poor spot welding.

[0005] In particular, when a heat-shrinkable group unit is further provided in the manufacturing apparatus of the cylindrical battery, the inner wall of the central hole (10) inside the group (7) is more prone to deformation (wrinkling or collapse). Therefore, it is difficult to smoothly insert the electrode rod (9) from the central hole (10) to the bottom of the group, which can easily cause poor bottom spot welding. Utility Model Content

[0006] This invention addresses the aforementioned problems and aims to provide a manufacturing apparatus for a cylindrical battery that can reduce the occurrence of poor bottom spot welding, as well as a cylindrical battery obtained using the same.

[0007] The manufacturing apparatus for the cylindrical battery of this utility model comprises, from the upstream to the downstream side of the production line, the following components: Group-forming units used to group the positive and negative electrodes together via a diaphragm; A group insertion unit for inserting the group into a metal housing with one end open; A bottom spot welding unit for inserting electrode rods from above into the center hole of the group up to the bottom of the group and performing welding; An electrolyte injection unit for injecting electrolyte into the metal casing; and A sealing unit for sealing the opening of the metal housing. Its features are, Between the group forming unit and the group insertion unit, there is also a center rod insertion unit for inserting a hollow tubular center rod into the center hole of the group.

[0008] Preferably, the sidewall of the central rod has multiple holes or slits.

[0009] Preferably, a heat-shrink unit for heat-shrinking the group is provided between the center rod insertion unit and the group insertion unit.

[0010] Preferably, between the bottom spot welding unit and the liquid injection unit, or between the group insertion unit and the bottom spot welding unit, a center rod removal unit for removing the center rod from the center hole of the group is also provided.

[0011] The cylindrical battery of this invention is characterized in that it is a cylindrical battery manufactured using the aforementioned cylindrical battery manufacturing apparatus. The cylindrical battery has a group consisting of a positive electrode and a negative electrode wound together by a separator, and a central rod inserted into a central hole in the group. The central rod is a hollow tube with one or more slits on its sidewall.

[0012] Preferably, the central rod is made of a non-metallic material.

[0013] Preferably, the central rod and the group are detachable separate structures.

[0014] Preferably, the slits are multiple parallel slits, the length of which is parallel to or inclined to the direction of the central axis of the central rod.

[0015] Preferably, the slit is a single slit extending continuously around the circumferential surface of the central rod or multiple slits extending intermittently, and its length direction is inclined relative to the direction of the central axis of the central rod.

[0016] Preferably, the slits are evenly distributed on the circumferential surface of the central rod.

[0017] Utility Model Effect The manufacturing apparatus for the cylindrical battery of this invention has a central rod insertion unit. The hollow tubular structure of the central rod can provide radial support to the battery, preventing the diaphragm at the central hole from wrinkling or collapsing. This allows the electrode rod to reach the bottom of the metal casing smoothly, greatly improving the welding yield of the bottom spot welding. Attached Figure Description

[0018] Figure 1 This is a block diagram schematically illustrating the structure of the manufacturing apparatus for the cylindrical battery of this utility model.

[0019] Figure 2 This is a side view schematically showing the working state of the bottom spot welding unit in the manufacturing apparatus for the cylindrical battery of this utility model.

[0020] Figure 3 This is a perspective view schematically showing the structure of the central rod used in the cylindrical battery of this utility model.

[0021] Figure 4 This is a side view schematically showing the working state of the bottom spot welding unit in a prior art cylindrical battery manufacturing apparatus. Detailed Implementation

[0022] The following description, with reference to the accompanying drawings, will illustrate the manufacturing apparatus for the cylindrical battery of this invention, and the specific embodiments of the cylindrical battery obtained by the manufacturing apparatus.

[0023] Figure 1 This is a block diagram schematically illustrating the structure of the manufacturing apparatus for the cylindrical battery of this utility model. Figure 2 This is a side view schematically showing the working state of the bottom spot welding unit in the manufacturing apparatus for the cylindrical battery of this utility model.

[0024] like Figure 1 As shown, the manufacturing apparatus for the cylindrical battery of this utility model comprises, from the upstream to the downstream side of the production line, the following components: (1) A group of positive and negative electrodes are wound together by a diaphragm to form a unit. The group is inserted into a group insertion unit (2) in a metal housing with one end open. The electrode rod is inserted from above into the center hole of the group until the bottom of the group, and the bottom spot welding unit (3) is welded. An injection unit (4) for injecting electrolyte into the metal casing; And a sealing unit (5) that seals the opening of the metal housing. Its features are, Between the group forming unit (1) and the group insertion unit (2), there is also a center rod insertion unit (6) into which a hollow tubular center rod is inserted in the center hole of the group.

[0025] In this invention, the positive and negative electrodes are wound into a group (7) by a group forming unit (1) through a diaphragm, and a central hole (10) is formed on the inner side of the group. A hollow tubular central rod (8) is inserted into the central hole (10) through a central rod insertion unit (6).

[0026] Therefore, as Figure 2 As shown, in the bottom spot welding unit (3), the electrode rod (9) can be inserted into the center hole (10) of the group (7) through the hollow tubular center rod (8).

[0027] Since the center rod (8) itself has a certain hardness, it can provide radial support for the group (7), thus preventing the diaphragm at the center hole (10) from wrinkling or collapsing. In addition, since the center rod (8) is a hollow tubular structure, the electrode rod (9) can smoothly reach the bottom of the metal shell through the center rod (8) to complete the bottom spot welding.

[0028] The central rod (8) preferably has a porous structure, for example, multiple holes or slits can be formed in its sidewalls. In this way, in the liquid injection unit (4), the hollow tubular structure of the central rod (8) allows the electrolyte to reach the bottom of the metal shell smoothly. In addition, the porous structure, such as the slits (11) formed in the sidewalls of the central rod (8) allows the electrolyte to diffuse smoothly radially into the interior of the group.

[0029] In the manufacturing apparatus for the cylindrical battery of this invention, it is preferable to further include a heat-shrinking unit for heat-shrinking the battery between the center rod insertion unit (6) and the battery pack insertion unit (2). This allows the heat-shrinked battery pack to be inserted more easily into the metal casing with one open end.

[0030] In addition, preferably between the bottom spot welding unit (3) and the liquid injection unit (4), or between the group insertion unit (2) and the bottom spot welding unit (3), there is also a center rod removal unit for removing the center rod (8) from the center hole (10) of the group (7).

[0031] By setting up a center rod extraction unit, the center rod (8) is extracted from the center hole (10) of the group (7), so that electrolyte can be injected more smoothly into the metal casing after the center rod (8) is extracted in the injection unit (4).

[0032] From the perspective of more reliably reducing the occurrence of bottom spot welding defects, the center rod pull-out unit is preferably located between the bottom spot welding unit (3) and the liquid injection unit (4). At this time, in the bottom spot welding unit (3), the electrode rod (9) can be inserted into the center hole of the group through the hollow tubular center rod (8), further reducing the damage to the diaphragm at the center hole on the inner side of the group (7) and reducing the occurrence of bottom spot welding defects.

[0033] On the other hand, from the perspective of minimizing the radial diameter of the battery, the center rod removal unit is preferably located between the group insertion unit (2) and the bottom spot welding unit (3). At this time, in the bottom spot welding unit (3), the electrode rod (9) is directly inserted into the center hole (10) of the group without passing through the center rod (8). Since the center rod (8) has already played a supporting and shaping role for the center hole (10) of the group before being removed, the occurrence of bottom spot welding defects can be effectively reduced even if the center rod (8) is not in the bottom spot welding unit (3).

[0034] If a hole or slit is provided on the center rod (8), it will not hinder the subsequent injection of electrolyte. Therefore, the center rod (8) does not need to be pulled out. That is, the setting of the center rod pull-out unit is not necessary.

[0035] This utility model also provides a cylindrical battery, characterized in that it is a cylindrical battery manufactured using the above-mentioned cylindrical battery manufacturing apparatus, having a group formed by winding a positive electrode and a negative electrode through a separator, and a central rod inserted into the central hole of the group.

[0036] Figure 3 This is a perspective view schematically showing the structure of the central rod used in the cylindrical battery of this utility model.

[0037] like Figure 3 As shown, the central rod (8) is a hollow tube with one or more slits (11) on its side wall. Preferably, the slits (11) are multiple parallel slits, and their length direction is parallel to or inclined to the direction of the central axis of the central rod.

[0038] In addition, the slit (11) is preferably a single slit that extends continuously around the circumferential surface of the central rod (8), or multiple slits that extend discontinuously. In this case, the length direction of the slit (11) is inclined relative to the direction of the central axis of the central rod (8).

[0039] Ideally, multiple slits should be evenly distributed on the circumference of the central rod. This facilitates the uniform penetration of the electrolyte into the group.

[0040] In addition, the center rod (8) is preferably made of a non-metallic material, such as an insulating material like polytetrafluoroethylene.

[0041] More preferably, the center rod (8) and the group are detachable separate structures. In this way, the center rod extraction unit can be flexibly set in the manufacturing apparatus of the cylindrical battery, or the center rod extraction unit can be omitted, depending on the needs.

[0042] This invention provides a manufacturing apparatus for a cylindrical battery, characterized by a center rod insertion unit that inserts a hollow tubular center rod into the center hole of the battery pack. Thus, after the battery pack is assembled, inserting the center rod into the center hole provides radial support, preventing deformation at the center hole during subsequent manufacturing processes and thus avoiding poor bottom spot welding. Furthermore, the hollow tubular structure of the center rod facilitates the insertion of electrode rods during bottom spot welding, and the porous or slit structure on the sidewall of the center rod facilitates electrolyte penetration, allowing the electrolyte to diffuse more smoothly into the battery pack.

[0043] In addition, this utility model also provides a cylindrical battery, characterized in that it includes the aforementioned central rod.

[0044] The above description, with reference to the accompanying drawings, illustrates several examples of the terminal connecting piece of this utility model. However, this utility model is not limited to the specific embodiments described above. Various modifications or element changes can be made without departing from the spirit of this utility model, and these modifications or element changes are also included within the protection scope of this utility model.

Claims

1. A manufacturing apparatus for a cylindrical battery, comprising, sequentially from the upstream to the downstream side of a production line: Group-forming units used to group the positive and negative electrodes together via a diaphragm; A group insertion unit for inserting the group into a metal housing with one end open; A bottom spot welding unit for inserting electrode rods from above into the center hole of the group up to the bottom of the group and performing welding; An injection unit for injecting electrolyte into the metal casing; as well as A sealing unit for sealing the opening of the metal housing. Its features are, Between the group forming unit and the group insertion unit, there is also a center rod insertion unit for inserting a hollow tubular center rod into the center hole of the group.

2. The apparatus for manufacturing a cylindrical battery according to claim 1, characterized in that, The sidewall of the central rod has multiple holes or slits.

3. The apparatus for manufacturing a cylindrical battery according to claim 1 or 2, characterized in that, Between the center rod insertion unit and the group insertion unit, there is also a heat shrink unit for heat shrinking the group.

4. The apparatus for manufacturing a cylindrical battery according to claim 1 or 2, characterized in that, Between the bottom spot welding unit and the liquid injection unit, or between the group insertion unit and the bottom spot welding unit, there is also a center rod removal unit for removing the center rod from the center hole of the group.

5. A cylindrical battery, characterized in that, The cylindrical battery is manufactured using the manufacturing apparatus for a cylindrical battery according to any one of claims 1 to 4. The cylindrical battery has a group consisting of a positive electrode and a negative electrode wound together by a separator, and a central rod inserted into a central hole in the group. The central rod is a hollow tube with one or more slits on its sidewall.

6. The cylindrical battery according to claim 5, characterized in that, The central rod is made of a non-metallic material.

7. The cylindrical battery according to claim 5 or 6, characterized in that, The central rod and the group are detachable separate structures.

8. The cylindrical battery according to claim 5 or 6, characterized in that, The slits are multiple parallel slits, and their length direction is parallel to or inclined to the direction of the central axis of the central rod.

9. The cylindrical battery according to claim 5 or 6, characterized in that, The slit is either a single slit extending continuously around the circumferential surface of the central rod or multiple slits extending intermittently, with its length direction inclined relative to the central axis of the central rod.

10. The cylindrical battery according to claim 8, characterized in that, The slits are evenly distributed on the circumferential surface of the central rod.

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