Battery and method for manufacturing the battery

Abstract

This manufacturing method comprises: a step for preparing a case having an opening at one end thereof and a bottom part at the other end thereof; a step for preparing an electrode group having a first electrode, a second electrode, and a collector lead electrically connected to the first electrode; a step for accommodating the electrode group in the case; and a joining step for joining the collector lead and the inner surface of the case. The joining step includes: a step of pressing a tubular pressing member against the collector lead such that the collector lead comes into contact with the inner surface of the case; and a step for welding the case and the collector lead in a state in which the inside of the tube of the pressing member is depressurized by a suction unit.

Description

[Technical field]

[0001] The present disclosure relates to a battery and a method for manufacturing the battery, and in particular to a battery in which a case and a current collecting lead of a current collector are electrically connected by welding, and a method for manufacturing the same. [Background technology]

[0002] Patent Document 1 discloses a manufacturing method in which, when joining and fixing a current collecting tab (positive electrode tab or negative electrode tab) to the inner surface of the bottom of a case, a center pin is inserted into the center of the electrode assembly and the current collecting tab is pressed against the bottom of the case while a laser is irradiated from the outside of the case to perform laser welding. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-012787 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, as in Patent Document 1, when the negative electrode lead and the case are joined by welding, it is required to weld without penetrating the negative electrode lead. This is because, when the negative electrode lead and the case are welded so that the molten part penetrates the negative electrode lead, there is a risk that spatter will be generated from the upper surface of the molten part of the negative electrode lead. If this conductive spatter gets mixed into the electrode assembly, it may cause a short circuit, and the reliability of the battery may decrease. On the other hand, when the negative electrode lead and the case are welded so as not to penetrate the negative electrode lead, it is required to strictly control the laser output or to perform welding within the application range of a limited laser output, which may decrease productivity. Therefore, the battery and the method for manufacturing the battery disclosed herein aim to provide a battery that is more reliable and has excellent workability. [Means for solving the problem]

[0005] A first aspect of the present disclosure relates to a method for manufacturing a battery, the method comprising the steps of: preparing a case having an opening at one end and a bottom at the other end; preparing an electrode group having a first electrode, a second electrode, and a current collecting lead electrically connected to the first electrode; housing the electrode group in the case; and joining the current collecting lead to an inner surface of the case, the joining step comprising the steps of pressing a tubular pressing member against the current collecting lead so that the current collecting lead abuts against the inner surface of the case; and welding the case and the current collecting lead while the inside of the tube of the pressing member is sucked by a suction part.

[0006] A second aspect of the present disclosure relates to a battery comprising an electrode group having a first electrode and a second electrode, a case housing the electrode group and having an opening at one end and a bottom at the other end, and a current collecting lead electrically connected to the first electrode and electrically connected to an inner surface of the case, the current collecting lead having melt marks formed on a first surface of the current collecting lead facing the case and on a second surface which is the reverse side of the first surface. Effect of the Invention

[0007] According to aspects of the present disclosure, when the case and the current collecting lead are laser welded together, the plume and / or spatter that occurs when the current collecting lead melts can be reduced, making it possible to manufacture a highly reliable battery in a cheaper and simpler manner. [Brief description of the drawings]

[0008] [Figure 1] 1 is a front cross-sectional view of a battery according to an embodiment of the present invention, as viewed from a vertical plane. [Diagram 2] 2 is an enlarged front cross-sectional view similar to FIG. 1 in a step of laser welding a negative electrode lead to a case. [Diagram 3] 3 is an enlarged cross-sectional view of a portion surrounded by a dashed ellipse shown in FIG. 2. [Figure 4]FIG. 2(a) is a plan view showing a second surface of the negative electrode lead, and (b) is a bottom view showing a first surface of the negative electrode lead. [Diagram 5] 13(a) to 13(c) are an enlarged bottom perspective view, a cross-sectional view taken along a vertical plane, and a bottom view showing a part of a pressing member according to a modified example of the present embodiment. [Figure 6] 1 is a block diagram showing a configuration of a manufacturing system for executing a battery manufacturing method according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] An embodiment of a battery and a method for manufacturing a battery according to the present disclosure will be described below with reference to the accompanying drawings. In the description of the embodiments, terms indicating directions (e.g., "vertical", "horizontal", "left and right", etc.) are used as appropriate to facilitate understanding, but these terms are used to explain the directions in the drawings and do not limit the present disclosure. In each drawing, in order to clarify the shape or characteristics of each component of the battery, the dimensions of these components are shown relative to each other and are not necessarily shown at the same scale. In addition, the same components are indicated by the same reference numerals in each drawing.

[0010] First, the configuration of the battery 1 will be described, and then a method for manufacturing the battery 1 according to the present embodiment and a specific configuration of the battery 1 obtained by the manufacturing method will be described below. Note that the manufacturing method for the battery and the battery of the present invention are not limited to the configuration and method of the following embodiment.

[0011] (Battery composition) FIG. 1 is a front cross-sectional view of a battery 1 according to this embodiment. The battery 1 shown in FIG. 1 includes an electrode group 10, a case 30 that houses the electrode group 10, and a sealing body 70 that closes the opening of the case 30. The electrode group 10 has a wound structure in which a first electrode 12 and a second electrode 22 are wound with a separator 11 interposed therebetween. That is, the battery 1 is a so-called cylindrical battery. In this embodiment, a cylindrical battery is illustrated as an example, but the application of the present invention is not limited thereto. Next, each component will be described below.

[0012] (electrode group) The electrode group 10 is formed as a columnar body having a hollow portion 20 extending in the winding axis direction by winding the first and second electrodes 12, 22 with the separator 11 interposed therebetween around a winding core (not shown) and then removing the winding core. The first electrode 12 usually has a first current collector sheet and a first active material layer formed on the surface thereof (both not shown). Meanwhile, the second electrode 22 usually has a second current collector sheet and a second active material layer formed on the surface thereof (both not shown).

[0013] The first electrode 12 is electrically connected to a conductive sealing body 70 via a first lead 14 made of conductive foil. On the other hand, the second electrode 22 is electrically connected to the inner surface of the case 30 via a second lead 24 also made of conductive foil.

[0014] In this embodiment, the inner surface of the case 30 is described as being the central part of the inner surface of the bottom 34 of the case 30, but is not limited to this and may be the side peripheral surface of the case 30 or a part of the bottom 34 other than the center (for example, the bottom surface biased toward the peripheral side surface), as long as the second lead 24 and the case 30 are electrically connected.

[0015] According to the present embodiment, such electrical connection is achieved by laser welding the case 30 and the second lead 24, and the second lead 24 has a fusion mark 38 laser-welded to the case 30. The fusion mark 38 of the second lead 24 may be configured to overlap with the hollow portion 20 of the electrode group 10 in the winding axis direction.

[0016] As will be described in detail later, the second lead 24 has a first surface 24a facing downward and a second surface 24b facing upward, which is the reverse side of the first surface 24a. The second lead 24 and the case 30 are welded so that the first surface 24a faces the bottom of the case 30. The melting mark 38 has a first melting mark 38a and a second melting mark 38b formed by laser welding on the first surface 24a and the second surface 24b of the second lead 24, and the area of ​​the first melting mark 38a is larger than the area of ​​the second melting mark 38b (FIG. 4).

[0017] In the battery 1 configured in this manner, the sealing body 70 functions as a first terminal (e.g., a positive electrode terminal) of the battery 1, and the case 30 functions as a second terminal (e.g., a negative electrode terminal) of the battery 1. Here, the components of the first and second electrodes 12, 22 when they are the positive electrode 12 and the negative electrode 22, respectively, will be described in further detail below.

[0018] The positive electrode 12 has a positive electrode current collector sheet and positive electrode active material layers formed on both sides thereof (not shown). When the battery 1 is a lithium ion battery, the positive electrode current collector sheet is made of a metal foil such as aluminum or an aluminum alloy, and the thickness of the sheet may be, but is not limited to, 10 μm to 20 μm.

[0019] The positive electrode active material layer includes, for example, a positive electrode active material, a binder, and a conductive agent. As the positive electrode active material of the lithium ion secondary battery, a lithium-containing composite oxide is preferable, and for example, LiCoO2, LiNiO2, LiMn2O4, etc. are used. As the positive electrode active material of the lithium ion primary battery, manganese dioxide, graphite fluoride, etc. are used. The thickness of the positive electrode active material layer may be, for example, 70 μm to 130 μm, but is not limited thereto.

[0020] The positive electrode lead 14 of the lithium ion secondary battery is formed using a material such as aluminum, an aluminum alloy, nickel, a nickel alloy, iron, stainless steel, etc., and may have a thickness of, for example, 10 μm to 120 μm. The positive electrode lead 14 is connected to the bottom surface of a sealing body 70 that also serves as a positive electrode terminal.

[0021] The negative electrode 22 has a negative electrode current collector sheet and a negative electrode active material layer formed on both sides thereof (not shown). When the battery is a lithium ion battery, the negative electrode current collector sheet is made of a metal foil such as stainless steel, nickel, copper, or a copper alloy, and the thickness of the negative electrode current collector sheet may be, but is not limited to, 5 μm to 20 μm.

[0022] The negative electrode active material layer contains, for example, a negative electrode active material, a binder, a conductive agent, etc. Examples of the negative electrode active material for a lithium ion battery include metallic lithium, alloys (silicon alloys, tin alloys, etc.), carbon materials (graphite, hard carbon, etc.), silicon compounds, tin compounds, lithium titanate, etc. The thickness of the negative electrode active material layer may be, for example, 70 μm to 150 μm, but is not limited thereto.

[0023] The negative electrode lead 24 of the lithium ion battery is formed using a material such as nickel, nickel alloy, iron, stainless steel, copper, or copper alloy, and the thickness thereof may be, for example, 10 μm to 200 μm. The width of the negative electrode lead 24 is not particularly limited as long as it is large enough to be accommodated in the case 30. The width of the negative electrode lead 24 may be, for example, 2 to 5 mm. The negative electrode lead 24 may have a single-layer structure made of one type of metal, or a multi-layer structure made of different metals for each layer. Examples of this multi-layer structure include a two-layer structure made of a Cu layer and a Ni layer, and a three-layer structure made of a Ni layer, a Cu layer, and a Ni layer. The negative electrode lead 24 does not have to be composed of only one for the battery 1. For example, a plurality of negative electrode leads 24 may be provided. Each of the plurality of negative electrode leads 24 may be individually joined to the bottom 34 of the case 30, or the tips of the plurality of leads 24 may overlap each other, and the overlapped portion may be joined to one point of the bottom 34 of the case 30.

[0024] The separator 11 interposed between the positive electrode 12 and the negative electrode 22 is formed using an insulating microporous thin film, woven fabric, or nonwoven fabric. The separator of the lithium ion battery may be formed using a polyolefin such as polypropylene or polyethylene, and its thickness is preferably 10 μm to 50 μm, and more preferably 10 μm to 30 μm.

[0025] (electrolyte) The electrolyte solution is composed of, for example, a lithium salt and a non-aqueous solvent that dissolves the lithium salt. The non-aqueous solvent may be, for example, a cyclic carbonate ester, a chain carbonate ester, or a cyclic carboxylate ester, and the lithium salt may be, for example, LiPF6, LiBF4, or the like, but is not limited thereto.

[0026] (case) The case 30 shown in FIG. 1 has a cylindrical shape, an opening at one end, and a bottom 34 that is closed at the other end. A ring-shaped groove 32 is formed near the end that forms the opening of the case 30. The case 30 may be cylindrical or elliptical, as long as it has a cylindrical shape. The case 30 is made of a material having electrical conductivity, and is made of stainless steel having a thickness of, for example, 0.1 mm to 1.0 mm, but is not limited thereto. A lower insulating plate 42 may be interposed between the bottom 34 of the case 30 and the electrode group 10. Furthermore, an upper insulating plate 43 may be provided between the upper part of the electrode group 10 and the case 30.

[0027] (sealing body) The sealing body 70 may be formed, for example, by stacking a plurality of members. The sealing body 70 may be formed by stacking a filter 71, a lower valve body 72, an insulating ring 73, an upper valve body 74, and a cap 75 in this order from the bottom. Specifically, the filter 71 and the lower valve body 72 are joined to each other at their respective peripheries. The center of the lower valve body 72 and the center of the upper valve body 74 are joined. An insulating ring 73 is interposed between the periphery of the lower valve body 72 and the periphery of the upper valve body 74. The periphery of the upper valve body 74 is joined to the periphery of the cap 75. The lower valve body 72 and the upper valve body 74 function as a safety mechanism for the battery 1. When the internal pressure of the case 30 increases, the lower valve body 72 breaks. Then, as the upper valve body 74 is pushed upward by the gas, the joint between the lower valve body 72 and the upper valve body 74 breaks, and the electrical connection between the upper valve body 74 and the lower valve body 72 is cut off. If the internal pressure of the case 30 increases further, the upper valve body 74 breaks, and the gas inside the case 30 passes through the cap 75 and is released to the outside of the battery 1. An insulating gasket 50 may be interposed between the sealing body 70 and the opening of the case 30. The gasket 50 has the function of insulating the sealing body 70 and the case 30, and sealing the opening of the case 30 together with the sealing body 70.

[0028] (Battery manufacturing method) The method for manufacturing the battery according to this embodiment will be described below. First, the electrode group 10 described above is prepared. The electrode group 10 is arranged in the case 30 so that the positive electrode lead 14 extends toward the opening of the case 30, and the negative electrode lead 24 extends toward the bottom 34 of the case 30. Furthermore, the portion of the negative electrode lead 24 that extends toward the bottom 34 of the case 30 beyond the electrode group 10 is bent and processed so as to be approximately parallel to the inner surface of the bottom. Furthermore, a ring-shaped lower insulating plate 42 having a hole in the center is interposed between the electrode group 10 and the bottom 34 of the case 30, and the electrode group 10 is inserted into the case 30 from the opening.

[0029] 2 is an enlarged front cross-sectional view similar to that of FIG. 1, showing a step of laser welding the negative electrode lead 24 to the bottom 34 of the case 30. As described above, the position at which the negative electrode lead 24 is laser welded to the case 30 is not limited to the central position of the bottom 34 of the case 30 as shown in the figure, but may be the peripheral side surface or the bottom surface adjacent to the peripheral side surface.

[0030] Next, a tubular pressing member 44 is prepared. The pressing member 44 may be a conduit made of, for example, stainless steel. The pressing member 44 is inserted into the hollow of the electrode group 10 arranged in the case 30. The outer diameter of the tubular pressing member 44 may be, for example, 2 mm or more and 4 mm or less. The inner diameter of the pressing member 44 may be, for example, 1.5 mm or more and 3 mm or less. In FIG. 2, the tubular pressing member 44 is illustrated exaggeratedly larger than actual size in order to make its features easier to understand.

[0031] The tubular pressing member 44 is connected to a suction unit (not shown) such as a vacuum pump, and is configured to suck the fluid together with the spatter P from the tube 45 of the pressing member 44 as the vacuum pump operates. The suction pressure of the tube 45 by the suction unit may be, for example, 50 kPa or more, or may be, for example, 70 kPa or more.

[0032] The pressing member 44 presses the negative electrode lead 24 toward the case 30 so that the negative electrode lead 24 abuts against (the inner surface of) the case 30. The inserting operation and pressing operation of the pressing member 44 may be performed manually by an operator, or may be performed automatically using a manipulator driven by a step motor (neither of which are shown).

[0033] After pressing the pressing member 44 against the negative lead 24 so that the negative lead 24 abuts against the case 30 (its inner surface), a laser beam LB is irradiated from the laser output unit toward the bottom 34 of the case 30, thereby laser welding the case 30 to the negative lead 24.

[0034] Fig. 3 is an enlarged cross-sectional view of a portion surrounded by a dashed ellipse α shown in Fig. 2. In the present disclosure, a region or portion of the case 30 that faces the negative electrode lead 24 and is irradiated with the laser beam LB is referred to as a facing portion. In the present application, a molten material (including one having continuity and integrity) made of the constituent materials of the case 30 and the negative electrode lead 24 is formed, and a region or portion that is externally recognized as being melted on the first surface 24a and the second surface 24b of the negative electrode lead 24 is referred to as melt marks 38a and 38b.

[0035] The laser beam LB may be a continuous wave laser beam or a pulsed laser beam. The laser output unit is not particularly limited in terms of the laser oscillation mechanism, but is preferably a laser oscillator using a fiber laser. Furthermore, the laser beam LB is preferably irradiated to a plurality of positions (three positions in Figs. 2 and 3) on the opposing portion of the bottom 34 of the case 30.

[0036] Incidentally, in order to connect the case 30 and the negative electrode lead 24 while reducing the electrical resistance between them, it is necessary to irradiate the outer surface of the bottom of the case 30 with a laser beam LB having an appropriate light intensity in order to continuously and integrally form a melting mark made of the constituent materials of both. However, as described above, the thickness of the case 30 is, for example, 0.1 mm to 1.0 mm. On the other hand, the thickness of the negative electrode lead 24 is, for example, 10 μm to 200 μm, and the negative electrode lead 24 is often thinner than the case 30. Therefore, it is not easy to perform laser welding while maintaining an appropriate light intensity of the laser beam LB. In particular, when the light intensity of the laser beam LB is smaller than the appropriate intensity, the electrical resistance between the case 30 and the negative electrode lead 24 increases, and the characteristics of the battery 1 are significantly impaired. On the other hand, when the light intensity of the laser beam LB is much greater than the appropriate intensity, a hole penetrating the case 30 and the negative electrode lead 24 is formed, and there is a risk of reducing the joining strength and mechanical strength.

[0037] Furthermore, the light intensity of the laser beam LB is strong, and although it does not reach the point of forming a through hole, sputter P consisting of a plume and / or sputter may be formed from the second surface 24b of the negative electrode lead 24. Since such sputter P is conductive, it may move inside the battery 1 filled with the electrolyte, causing a leak current between the positive electrode 12 and the negative electrode 22, or may cause a short circuit between the positive electrode 12 and the negative electrode 22.

[0038] Therefore, the manufacturing method of the battery 1 according to this embodiment includes a step of discharging the air from inside the tube 45 of the pressing member 44 with a decompression pump. This reduces the plume and / or sputter generated from the second surface 24b of the negative electrode lead 24 due to laser welding from inside the battery 1, and makes it possible to prevent leakage current / short circuit between the positive electrode 12 and the negative electrode 22.

[0039] After the negative electrode lead 24 is welded to the case 30, an upper insulating plate 43 is provided above the electrode group 10. Then, the positive electrode lead 14 is inserted into a hole formed in the upper insulating plate 43. The positive electrode lead 14 that has passed through the upper insulating plate 43 is pulled out from the opening of the case 30 and welded to the filter 71 of the sealing body 70 arranged in the gasket 50. An electrolyte is poured into the inside of the case 30 by a decompression method. Then, an annular groove 32 is formed in the side wall of the case 30. Finally, the sealing body 70 is arranged together with the gasket 50 on the inner surface of the groove 32, and the end of the case 30 is crimped to the peripheral portion of the sealing body 70 via the gasket 50, thereby manufacturing a cylindrical battery 1.

[0040] (Negative electrode lead shape) Fig. 4(a) is a plan view showing the second surface 24b of the negative electrode lead 24, and Fig. 4(b) is a bottom view showing the first surface 24a of the negative electrode lead 24. Fig. 4(a) and Fig. 4(b) also show a plurality of melt marks 38 formed by the irradiation of the laser beam LB from the melted material of the case 30 and the negative electrode lead 24. Note that in Figs. 4(a) and (b), the outline of some of the components appearing in the figures is shown by dashed lines so that the shape of the melt marks 38 is emphasized in the figures.

[0041] As shown in the figure, the area of ​​the melting mark 38b (also called the second melting mark) formed on the second surface 24b of the negative electrode lead 24 is smaller than the area of ​​the melting mark 38a (also called the first melting mark) formed on the first surface 24a. The melting marks 38 may be formed on the first surface 24a and the second surface 24b so as to extend linearly and be spaced apart from each other. By forming the melting mark 38b on the second surface 24b of the negative electrode lead 24, it becomes possible to check the melting state of the negative electrode lead 24 and the bonding state between the negative electrode lead 24 and the case 30, which were previously covered by the case 30 and could not be seen, by looking at whether or not there is a melting mark 38b on the second surface 24b. Therefore, it becomes possible to simplify the inspection process for checking the bonding state.

[0042] The shape of the melt mark 38 does not have to extend linearly as described above. For example, the melt mark 38 may be formed in a plurality of dots (spots) on the first surface 24a and the second surface 24b. In addition, as shown in Figures 4(a) and 4(b), the extension direction of the linear melt mark 38 does not have to extend in a direction perpendicular to the extension direction of the negative electrode lead 24 that extends approximately parallel to the bottom 34 of the case 30.

[0043] FIG. 5(a) is a bottom perspective view showing an enlarged portion of the pressing member 44 according to a modified example of the present embodiment, FIG. 5(b) is a front cross-sectional view showing an enlarged portion of the pressing member 44 according to the modified example, and FIG. 5(c) is a bottom view of the pressing member 44 according to the modified example. Note that FIG. 5(b) is a front cross-sectional view taken along line VB-VB in FIG. 5(c). As shown in FIG. 5, a notch 45a may be formed at the tip of the tube 45. With this configuration, when the pressing member 44 abuts against the negative electrode lead 24 and the inside of the tube of the pressing member 44 is sucked, the inside of the tube 45 is prevented from being blocked by the negative electrode lead 24. Therefore, a gas flow is generated that flows from inside the case 30 into the tube 45 of the pressing member 44 through the notch 45a, making it easier to generate an air flow in the tube of the pressing member 44. Therefore, it becomes easier to suck spatters and the like. In addition, the inner diameter of the tube 45 may be larger than the width of the negative electrode lead 24. Even in this configuration, the inside of the tube 45 of the pressing member 44 can be prevented from being sealed by the negative electrode lead 24 .

[0044] (Manufacturing System) The manufacturing method according to the present embodiment is preferably performed in-line (automatically). FIG. 6 is a block diagram showing the configuration of a manufacturing system 100 that performs the manufacturing method of the battery according to the present disclosure. As described above, the manufacturing system 100 includes a vacuum pump 102 that exhausts air from the tube 45 of the pressing member 44, a manipulator 104 that drives the insertion operation of the pressing member 44 into the hollow portion 20 and the pressing operation against the negative electrode lead 24, and a laser output unit 106 that laser-welds the case 30 to the negative electrode lead 24 by irradiating a laser beam LB toward the bottom surface of the case 30. The manufacturing system 100 also includes a control unit 110 that controls the operations of the vacuum pump 102, the manipulator 104, and the laser output unit 106. The manufacturing system 100 also includes a pressure sensor 112 that monitors the air pressure in the tube 45 of the pressing member 44, and an input / output unit 114 (machine interface). The input / output unit 114 is configured to set the light intensity of the laser beam LB output from the laser output unit 106 during laser welding, as well as the degree of reduced pressure (vacuum degree) and flow rate in the tube 45 of the pressing member 44, and to display the air pressure in the tube 45 detected by the pressure sensor 112.

[0045] Using the input / output unit 114, the operator can set the pressing force with which the pressing member 44 presses the negative electrode lead 24 downward during the pressing operation, and the light intensity of the laser beam LB output from the laser output unit 106 as well as the degree of reduced pressure (vacuum degree) and flow rate within the tube 45 of the pressing member 44 during laser welding.

[0046] The control unit 110 of the manufacturing system 100 controls the manipulator 104 so that the pressing member 44 presses the negative electrode lead 24 with a pressing force set by the input / output unit 114, and controls the laser output unit 106 to output a laser beam LB of a similarly set light intensity during laser welding, and reduces the pressure inside the tube 45 of the pressing member 44 to the desired degree of reduction in pressure.

[0047] As the laser welding progresses, a part of the negative electrode lead 24 (a part corresponding to the fusion mark 38) melts, and spatters and the like occur inside the tube 45 of the pressing member 44. At this time, the degree of reduced pressure inside the tube 45 decreases (the pressure increases). The pressure sensor 112 monitors the air pressure inside the tube 45 of the pressing member 44 and feeds it back to the control unit 110, and the control unit 110 is configured to control the reduced pressure pump 102 so that the monitored pressure inside the tube 45 becomes substantially stable. In this way, the manufacturing method according to this embodiment can be performed in-line. [Industrial Applicability]

[0048] The present disclosure can be utilized in a battery in which a case and a lead are laser-welded and in a method for manufacturing the battery. [Explanation of symbols]

[0049] REFERENCE SIGNS LIST 1...battery, 10...electrode group, 11...separator, 12...first electrode (positive electrode), 14...first lead (positive electrode lead), 20...hollow portion, 22...second electrode (negative electrode), 24...second lead (negative electrode lead), 24a...first surface, 24b...second surface, 30...case, 32...groove portion, 34...bottom portion, 38...melt mark, 38a...first melt mark, 38b...second melt mark, 42...lower insulating plate, 43...upper insulating plate, 44...press Pressure member, 45... tube, 45a... notch, 50... gasket, 70... sealing body, 71... filter, 72... lower valve body, 73... insulating ring, 74... upper valve body, 75... cap, 100... manufacturing system, 102... pressure reducing pump, 104... manipulator, 106... laser output unit, 110... control unit, 112... pressure sensor, 114... input / output unit (machine interface), LB... laser beam, P... sputter

Claims

1. Providing a case having an opening at one end and a bottom at the other end; preparing an electrode group having a first electrode, a second electrode, and a current collecting lead electrically connected to the first electrode; A step of housing the electrode group in the case; a joining step of joining the current collecting lead to an inner surface of the case, The joining step includes: a step of pressing a tubular pressing member against the current collecting lead so that the current collecting lead abuts against an inner surface of the case; a step of welding the case and the current collecting lead together while the inside of the tube of the pressing member is sucked by a suction part; A method for manufacturing a battery comprising: the electrode group is configured by winding the first electrode and the second electrode with a separator interposed therebetween, and has a hollow portion extending in a winding axis direction, In the joining step, The pressing member is inserted into the hollow portion and presses the current collecting lead; A method for manufacturing a battery, wherein the bottom of the case and the current collecting lead are welded within the tube of the pressing member when viewed from the one end.

2. When the current collecting lead is welded to the case, plume and / or spatters generated when the current collecting lead melts are sucked in. A method for producing the battery according to claim 1 .

3. an inner surface of the case has a facing portion facing the current collecting lead, a laser beam is irradiated from outside the case onto the facing portion, thereby welding the current collecting lead to the case; A method for producing the battery according to claim 1 or 2.

4. monitoring the pressure or flow rate in the tube of the pressing member; and adjusting the pressure or flow rate in the pressing member so that the monitored pressure or flow rate in the tube of the pressing member is substantially stable. The method for producing the battery according to any one of claims 1 to 3.

5. the current collecting lead has a first surface that contacts the case and a second surface that is a reverse surface of the first surface, In the joining step, when the case and the current collecting lead are welded together, the current collecting lead is melted from the first surface to the second surface. The method for producing the battery according to any one of claims 1 to 4.

6. Providing a case having an opening at one end and a bottom at the other end; preparing an electrode group having a first electrode, a second electrode, and a current collecting lead electrically connected to the first electrode; A step of housing the electrode group in the case; a joining step of joining the current collecting lead to an inner surface of the case, The joining step includes: a step of pressing a tubular pressing member against the current collecting lead so that the current collecting lead abuts against an inner surface of the case; a step of welding the case and the current collecting lead together while the inside of the tube of the pressing member is sucked by a suction part; A method for manufacturing a battery comprising: the current collecting lead has a first surface that contacts the case and a second surface that is a reverse surface of the first surface, In the joining step, when the case and the current collecting lead are welded together, the current collecting lead is melted from the first surface to the second surface, A method for manufacturing a battery, wherein the case and the current collecting lead are welded within the tube of the pressing member, as viewed from the one end.

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