JP2015103308A - Manufacturing method of sealed battery, and sealed battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a sealed battery in which an electrode body can be accommodated in a case body part by easily inserting a positive electrode terminal and a negative electrode terminal that the electrode body includes into through holes of the case body part, and the sealed battery.SOLUTION: According to the manufacturing method of the sealed battery, a bottomed cylindrical case body part 21 is manufactured which includes a bottom part 25 at an opposite side of an opening 22 and with which a pair of through holes 29 are formed in the bottom part 25. An electrode body 10 including a positive electrode terminal 14 and a negative electrode terminal 16 is accommodated in the case body part 21, the positive electrode terminal 14 is inserted into one through hole 29, and the negative electrode terminal 16 is inserted into the other through hole 29. A cover body 23 that covers the opening 22 is then joined to the case body part 21 by welding. Guide rods 30 are coaxially connected to the positive electrode terminal 14 and the negative electrode terminal 16, respectively, the guide rod 30 of the positive electrode terminal 14 is inserted into the one through hole 29, the guide rod 30 of the negative electrode terminal 16 is inserted into the other through hole 29, and te electrode body 10 is accommodated in the case body part 21.

Description

  The present invention relates to a method for manufacturing a sealed battery and a sealed battery.

A secondary battery such as a lithium secondary battery or a nickel hydride secondary battery generally employs a sealed structure.
For example, as shown in FIG. 6, a sealed battery having a square shape includes a case main body 50 formed in a bottomed cylindrical shape, an electrode body 51 including a positive electrode terminal 52 and a negative electrode terminal 53, and a case main body. And a lid 55 that covers the opening 54 of the unit 50.
In this sealed battery, the electrode body 51 is housed in the case body 50, the lid body 55 is attached to the opening 54 of the case body section 50, and the opening 54 of the case body section 50 and the outer periphery of the lid body 55 are connected. It is produced by sealing.
The case main body 50 and the lid 55 are made of a metal material (for example, aluminum), and the opening 54 of the case main body 50 and the outer periphery of the lid 55 are sealed by laser welding.

By the way, the lid 55 of the sealed battery has a through hole 56 through which the positive electrode terminal 52 and the negative electrode terminal 53 of the electrode body 51 are inserted, and opens when the internal pressure of the sealed battery reaches a predetermined pressure. A safety valve 57 is formed.
The positive electrode terminal 52 and the negative electrode terminal 53 are insulated from the lid body 55 and are provided with a seal member (not shown) for preventing leakage of the electrolytic solution from the through hole 56.
Since the seal member and the safety valve 57 provided on the lid 55 are located relatively close to the location of laser welding, they are easily affected by heat (material alteration or deformation) due to laser welding.

Therefore, in order to prevent the seal member and the safety valve from being affected by the heat caused by laser welding, for example, a sealed battery shown in FIG. 7 can be considered.
In the sealed battery shown in FIG. 7, a through-hole through which the positive electrode terminal 52 and the negative electrode terminal 53 of the electrode body 51 are inserted into the bottom 62 that is opposite to the opening 61 of the case main body 60 formed in a bottomed cylindrical shape. 63 and a safety valve 64 are formed.
The lid 65 attached to the opening 61 is formed by a flat plate.
Therefore, when the electrode body 51 is housed in the case main body 60, the electrode body 51 is inserted into the case main body 60 from the side where the positive electrode terminal 52 and the negative electrode terminal 53 are provided, and the case main body 60 is inserted into the opening 61. A flat lid 65 is attached, and the opening 61 of the case body 60 and the outer periphery of the lid 65 are sealed by laser welding.
Since the seal member and the safety valve 64 are located away from the place where laser welding is performed, they are not affected by heat from laser welding.

Moreover, as a related prior art, the manufacturing method of the sealed battery disclosed by patent document 1 is known, for example.
In the method for manufacturing a sealed battery disclosed in Patent Document 1, an outer can manufacturing step for manufacturing a bottomed cylindrical outer can, a sealing plate manufacturing step for manufacturing a sealing plate for sealing an opening of the outer can, A laser beam is applied to the boundary between the housing step for storing the power generation element body in the outer can, the mounting step for attaching the sealing plate to the opening of the outer can, and the outer peripheral portion of the sealing plate and the opening edge of the outer can. Welding step.
And the sealing plate production step includes a step forming step for forming a stepped portion on the outer surface side of the sealing plate plate material by forming a stepped portion in the thickness direction along the line that becomes the outer periphery of the sealing plate. It is.

According to the method for manufacturing a sealed battery disclosed in Patent Document 1, when the outer periphery of the sealing plate and the opening edge of the outer can are sealed by laser welding by forming the stepped portion, the central portion of the sealing plate from the welding location. Since there is no linear heat transfer path to the heat dissipation, the heat radiation from the welded portion is reduced.
Therefore, since the thermal stress generated at the welded portion is reduced, the crack generation rate can be kept low even if the energy of laser irradiation is lowered.

Moreover, as another prior art, the battery disclosed by patent document 2 can be mentioned, for example.
The battery disclosed in Patent Document 2 includes an electrode body having a positive electrode plate, a negative electrode plate, and a separator, an inner case that houses the electrode body and has an upper opening, an outer case that covers the inner case from below, and an inner case. An outer lid member that is covered from above and whose lower end is fixed to the outer lid member by welding at a position lower than the opening position of the inner case.
In the battery disclosed in Patent Document 2, the lower part of the inner case that houses the electrode body is housed in the outer case, and the outer lid in which the electrode terminals (the positive terminal and the negative terminal) are fixed above the inner case. Arrange the members.
Then, the base end portion of the positive electrode terminal is fixed to the tip end portion of the positive electrode lead included in the electrode body, and the base end portion of the negative electrode terminal is fixed to the tip end portion of the negative electrode lead by welding.
Next, the outer lid member and the outer case are joined.

JP 2000-268781 A JP 2012-199021 A

However, in the sealed battery shown in FIG. 7, when the electrode body 51 is housed in the case body 60, the positive terminal 52 and the negative terminal 53 of the electrode body 51 are aligned with the through hole 63 of the case body 60 and inserted. There is a problem that it is difficult to accommodate the electrode body 51 in the case main body 60.
Moreover, in the manufacturing method of the sealed battery disclosed in Patent Document 1, a stepped portion is formed by denting the center side in the thickness direction along a line that becomes the outer periphery of the sealing plate on the outer surface side of the sealing plate material. Therefore, there is a problem that the manufacturing cost increases.
Since the battery disclosed in Patent Document 2 is an external lid member to which the positive electrode terminal and the negative electrode terminal are fixed, before welding the external lid member and the external case, the positive electrode terminal, the negative electrode terminal, and the electrode body are connected. There is a problem of requiring work to connect.

  The present invention has been made in view of the above problems, and an object of the present invention is to easily insert the positive electrode terminal and the negative electrode terminal of the electrode body into the through hole of the case main body portion, and place the electrode body in the case main body portion. It is in the manufacturing method of the sealed battery which can be accommodated, and provision of a sealed battery.

  In order to solve the above problems, the present invention provides a bottomed cylindrical case body having an opening and a bottom on the opposite side of the opening, and a pair of through holes formed in the bottom. The case body includes an electrode body including a positive electrode terminal and a negative electrode terminal. The positive electrode terminal is inserted into one through hole of the pair of through holes, and the negative electrode terminal is inserted into the other through hole. In a manufacturing method of a sealed battery in which a lid that covers an opening is joined to the case body by welding, a guide rod is connected to the positive terminal and the negative terminal coaxially, and is connected to the positive terminal The guide rod is inserted into the one through hole, the guide rod connected to the negative electrode terminal is inserted into the other through hole, and the electrode body is accommodated in the case main body. .

According to the present invention, when the electrode body is housed in the case main body, the guide rod connected to the positive electrode terminal and the negative electrode terminal is inserted into the corresponding through holes, so that the positive electrode terminal and the negative electrode terminal of the electrode body are inserted into the case. It can be easily positioned and inserted through the through hole of the main body.
Even when a sealing member or a safety valve is provided at the bottom, the sealing member and the safety valve are not far from the welding due to the presence of the sealing member and the safety valve at a position far away from the welding location.

Further, in the above sealed battery manufacturing method, the positive terminal and the negative terminal may be provided with bolt holes, and the guide rod may be provided with a bolt shaft portion screwed into the bolt hole at a connection side end portion. .
In this case, the guide rod is connected to the positive terminal and the negative terminal by screwing the bolt shaft portion of the guide rod into the bolt hole of the positive terminal and the negative terminal. Easy to attach and detach.

In the above-described method for manufacturing a sealed battery, the guide rod may include a reduced diameter portion that decreases in diameter toward the distal end side.
In this case, when the electrode body is stored in the case body, the guide rod is easily inserted into the through hole, and the positive terminal and the negative terminal of the electrode body can be easily inserted through the through hole of the case body.

  The present invention also includes a bottomed cylindrical case body having an opening and a bottom on the opposite side of the opening, a pair of through holes formed in the bottom, a positive electrode terminal, and a negative electrode terminal, A sealed battery comprising: an electrode body housed in a case main body; and a lid that covers the opening and is joined to the case main body by welding, wherein the positive terminal and the negative terminal are bolts Each of the holes has a hole, and the bolt hole can be screwed into a bolt shaft provided at a connection side end of a guide rod that can be coaxially connected to the positive terminal and the negative terminal.

According to the present invention, the guide rod can be connected to the positive terminal and the negative terminal by screwing the bolt shaft of the guide rod into the bolt holes of the positive terminal and the negative terminal.
Therefore, the positive electrode terminal and the negative electrode terminal of the electrode body can be easily aligned and inserted into the through hole of the case body using the guide rod.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of a sealed battery which can insert the positive electrode terminal and negative electrode terminal with which an electrode body is provided to the through-hole of a case main-body part, and can accommodate an electrode body in a case main-body part, and a sealed battery Can be provided.

1 is a perspective view of a sealed battery according to an embodiment of the present invention. It is a disassembled perspective view of the sealed battery which concerns on embodiment of this invention. It is a front view of the electrode body and guide rod in a sealed battery. It is explanatory drawing explaining the manufacturing method of the sealed battery which concerns on embodiment of this invention. It is a side view of the guide rod which concerns on a modification. It is a perspective view explaining the manufacturing method of the conventional sealed battery and a sealed battery. It is a perspective view explaining another conventional sealed battery and the manufacturing method of a sealed battery.

Hereinafter, a manufacturing method of a sealed battery and a sealed battery according to an embodiment of the present invention will be described with reference to the drawings.
The sealed battery according to this embodiment is a vehicle-mounted secondary battery, for example, a lithium secondary battery or a nickel hydride secondary battery.

The sealed battery shown in FIG. 1 has a flat, substantially rectangular parallelepiped electrode body 10 as a power generation element, and a battery case 20 that houses the electrode body 10.
As shown in FIG. 2, the electrode body 10 includes a sheet-like positive electrode 11 and a negative electrode 12, and a sheet-like separator 13 interposed between the positive electrode 11 and the negative electrode 12.
The separator 13 is formed of an insulating material that enables the electrolytic solution filled in the battery case 20 to flow.
In the electrode body 10, the positive electrodes 11 and the negative electrodes 12 are alternately stacked via separators 13.
The electrode body 10 includes a positive electrode current collector 15 connected to the positive electrode terminal 14 and a negative electrode current collector 17 connected to the negative electrode terminal 16.

The positive electrode terminal 14 and the negative electrode terminal 16 are formed in a cylindrical shape.
In the present embodiment, the positive electrode terminal 14 and the negative electrode terminal 16 have the same axial length and outer peripheral diameter.
A bolt hole 18 that is coaxial with the axis of the positive electrode terminal 14 is formed at the center of the positive electrode terminal 14, and similarly, a bolt hole 19 that is coaxial with the axis of the negative electrode terminal 16 is formed at the center of the negative electrode terminal 16. Has been.
The hole diameters, hole depths, and screw pitches of the bolt holes 18 and 19 are set to be the same.
The bolt holes 18 and 19 are formed to connect the guide rod 30 shown in FIG. 3 used when the electrode body 10 is accommodated in the battery case 20.
Details of the guide rod 30 will be described later.

The battery case 20 has a flat, substantially rectangular parallelepiped shape as a whole.
The battery case 20 includes a bottomed cylindrical case main body 21 and a rectangular lid 23 that seals the opening 22 of the case main body 21.
The lid 23 is fixed to the case body 21 by laser welding.
Both the case body 21 and the lid 23 are made of a metal material (for example, aluminum).

The case main body portion 21 includes a cylindrical side wall portion 24 having a rectangular cross section, and a bottom portion 25 formed so as to close an end portion of the case main body portion 21 opposite to the opening 22.
A safety valve 26 is provided near the center of the bottom 25 in the longitudinal direction.
The safety valve 26 has a function of opening when the pressure in the battery case 20 reaches a predetermined pressure due to the generation of gas in the battery case 20 and releasing the gas in the battery case 20 to the outside.
The lid 23 is provided with a liquid injection port 27 for injecting the electrolytic solution into the battery case 20, and the liquid injection port 27 is sealed with a sealing member 28.
In the present embodiment, the safety valve 26 and the liquid injection port 27 exist at positions far away from the opening 22 where the lid body 23 is welded in the case main body 21.

Further, a pair of circular through holes 29 and 29 are formed near both ends in the longitudinal direction of the lid body 23.
The positive terminal 14 is inserted into one through hole 29, and the negative terminal 16 is inserted into the other through hole 29.
The diameter of the through hole 29 is set to be slightly larger than the outer diameters of the positive terminal 14 and the negative terminal 16.
In a state where the electrode body 10 is accommodated in the battery case 20, the positive terminal 14 and the negative terminal 16 protrude from the through hole 29.
An annular seal member (not shown) surrounding the positive electrode terminal 14 and the negative electrode terminal 16 is attached.
The sealing member is formed of a resin material, and surrounds the periphery of the through hole 29 inside the bottom 25 of the case main body 21 to prevent leakage of the electrolytic solution from the through hole 29.
Further, the positive terminal 14 and the negative terminal 16 are insulated from the case body 21.
In the present embodiment, the through-hole 29 exists at a position far from the opening 22 where the lid body 23 is welded in the case main body 21.

Next, the manufacturing method of the sealed battery of this embodiment will be described.
As shown in FIG. 3, first, the guide rod 30 is connected to the positive electrode terminal 14 and the negative electrode terminal 16 of the electrode body 10 manufactured in advance.
An annular seal member (not shown) is attached to the positive terminal 14 and the negative terminal 16 in advance.

The guide rod 30 is a jig for facilitating insertion of the positive terminal 14 and the negative terminal 16 into the through hole 29 of the case main body 21.
As shown in FIG. 3, the guide rod 30 includes a rod body portion 31 that is a round bar.
In the present embodiment, the outer diameter of the rod main body 31 is the same as the outer diameter of the positive terminal 14 and the negative terminal 16.
A bolt shaft that allows the guide rod 30 to be connected to the positive electrode terminal 14 and the negative electrode terminal 16 by screwing into the bolt holes 18 and 19 at one end of the rod main body portion 31 on the proximal end side of the guide rod 30. A portion 32 is formed.
One end of the rod main body 31 corresponds to a connecting side end.
A conical diameter-reduced portion 33 is formed at the other end of the rod main body 31 on the distal end side of the guide rod 30 and has a diameter reduced toward the distal end.
The reduced diameter portion 33 facilitates the insertion of the guide rod 30 into the through hole 29.
The length L1 of the same diameter portion having the same outer diameter in the rod main body 31 is set to be larger than the length L2 from the opening 22 to the bottom 25 of the case main body 21.

After connecting the guide rod 30 to the positive electrode terminal 14 and the negative electrode terminal 16 of the electrode body 10, the electrode body 10 is moved toward the opening 22 of the case main body 21, and the guide rod 30 is moved from the opening 22 to the case main body. Insert into 21.
As shown in FIG. 4 (a), the reduced diameter portion 33 of the guide rod 30 is inserted through the through hole 29, and as shown in FIG. 4 (b), the same diameter portion of the rod main body portion 31 is the through hole. When it is inserted through 29, the position of the electrode body 10 with respect to the case body 21 is determined.
After the rod body portion 31 is inserted into the through hole 29 having the same diameter, the electrode body 10 is further moved, so that the positive terminal 14 and the negative terminal 16 are inserted into the through hole 29 as shown in FIG. In addition, the electrode body 10 is accommodated in the case main body 21.

Next, as shown in FIG. 4D, the guide rod 30 is removed from the positive terminal 14 and the negative terminal 16.
After removing the guide rod 30 from the positive electrode terminal 14 and the negative electrode terminal 16, the positive electrode terminal 14, the negative electrode terminal 16, and the case main body 21 are fixed to each other using a fastening member (not shown) such as a nut.
Next, the lid body 23 is attached to the opening 22, and the lid body 23 is joined to the case body 21 by laser welding.
By joining the lid body 23 to the case body 21 by laser welding, the opening 22 is completely sealed, and the housing of the electrode body 10 in the battery case 20 is completed.
After the electrode body 10 is accommodated in the battery case 20, the electrolytic solution is injected from the injection port 27, and the injection port 27 is sealed by the sealing member 28 after the injection of the electrolytic solution.
After the liquid injection port 27 is sealed, a sealed battery is completed through subsequent processes such as an aging process and a charge / discharge activation process.
4 (a) to 4 (d), only the case main body portion 21 is shown broken for convenience of explanation.

This embodiment has the following effects.
(1) When the electrode body 10 is housed in the case body 21, the guide rods 30 connected to the positive terminal 14 and the negative terminal 16 are inserted through the corresponding through holes 29. For this reason, the positive electrode terminal 14 and the negative electrode terminal 16 of the electrode body 10 can be easily positioned and inserted into the through hole 29 of the case main body 21. Even when a seal member (not shown) or a safety valve 26 is provided on the bottom 25 of the case main body 21, the seal member and the safety valve 26 exist at positions far away from the location of laser welding. It is not affected by heat (material alteration or deformation).

(2) Connecting the guide rod 30 to the positive terminal 14 and the negative terminal 16 by screwing the bolt shaft portion 32 of the guide rod 30 into the bolt hole 18 of the positive terminal 14 and the bolt hole 19 of the negative terminal 16, respectively. Can do. Thereby, the guide rod 30 can be easily attached to and detached from the positive electrode terminal 14 and the negative electrode terminal 16.

(3) Since the guide rod 30 is provided with the reduced diameter portion 33 that is reduced in diameter toward the distal end portion side, the guide rod 30 is inserted into the through hole 29 when the electrode body 10 is stored in the case body portion 21. It becomes easy to be done. Therefore, the positive electrode terminal 14 and the negative electrode terminal 16 of the electrode body 10 can be easily inserted through the through hole 29 of the case body 21.

(4) Since the bolt hole 18 (19) is formed at the center of the positive electrode terminal 14 (negative electrode terminal 16), the outer diameter of the guide rod 30 is set to be equal to or smaller than the outer diameter of the positive electrode terminal 14 (negative electrode terminal 16). It is possible. For example, when a male screw is formed on the positive terminal (negative terminal) and the terminal itself is a bolt, and the bolt hole into which the bolt can be screwed is formed on the guide rod, the outer diameter of the guide rod is the outer diameter of the bolt. It is necessary to enlarge the through hole of the case body. However, in the case of the present embodiment, the outer diameter of the guide rod 30 can be set according to the diameter of the through hole 29.

Next, a guide rod 40 according to a modification shown in FIG. 5 will be described.
In the guide rod 40 according to the modification, the entire rod main body 41 is a conical body having a diameter reduced from the base side toward the tip side.
A hexagonal column portion 42 having a hexagonal cross section is formed on the base side of the rod main body portion 41, and the hexagonal column portion 42 is provided to facilitate the rotation of the guide rod 40 with a tool such as a spanner.
A bolt shaft portion 43 that can be screwed into the positive electrode terminal 14 and the negative electrode terminal 16 is formed at an end portion of the hexagonal column portion 42 that is opposite to the end portion on the rod main body portion 41 side.
That is, the guide rod 40 includes the bolt shaft portion 43 at the connection side end.
When the guide rod 40 according to the modification is used, the guide rod 40 can be attached to and detached from the positive terminal 14 and the negative terminal 16 with a tool such as a spanner, and the guide rod 40 can be attached to and detached from the positive terminal 14 and the negative terminal 16 more easily. It will be certain.

  The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the gist of the invention. For example, the following modifications may be made.

○ In the above embodiment, the electrode body is moved toward the case body to accommodate the electrode body in the case body. However, the case body is moved toward the electrode body and the electrode is moved to the case body. You may make it accommodate a body.
In the above embodiment, after the electrode body is accommodated in the case main body, the guide rod is removed from the positive electrode terminal and the negative electrode terminal, and the positive electrode terminal, the negative electrode terminal, and the case main body portion are mutually connected using a fastening member such as a nut. Fixed but not limited to this. For example, after housing the electrode body in the case body, the positive and negative terminals and the case body are fixed to each other without removing the guide rod from the positive and negative terminals, and then the guide rod is removed. Also good.
○ In the above embodiments and modifications, the guide rod is provided with a conical reduced diameter portion or the rod body is formed in a conical shape with respect to the through hole. Can be reliably performed, the rod body portion of the guide rod may have only the same diameter portion.
○ In the above embodiment, the positive electrode terminal and the negative electrode terminal have the same shape and the bolt holes of the positive electrode terminal and the negative electrode terminal are also the same, but when the positive electrode terminal and the negative electrode terminal are different from each other, The bolt holes of the terminals may also be different from each other. In this case, the guide rods may have different configurations so as to match the configurations of the positive electrode terminal and the negative electrode terminal to be connected.
In the above embodiment, the lid body 23 is fixed to the case main body 21 by laser welding, but may be fixed by friction stir welding.

10, 51 Electrode body 14, 52 Positive terminal 16, 53 Negative terminal 18 Bolt hole (positive electrode)
19 Bolt hole (negative electrode)
20 Battery case 21, 50, 60 Case body 22, 54, 61 Opening 23, 65 Lid 25, 62 Bottom 26, 57, 64 Safety valve 27 Injection port 29, 56, 63 Through hole 30, 40 Guide rod 31 , 41 Rod body portion 32, 43 Bolt shaft portion 33 Reduced diameter portion 42 Hexagonal column portion

Claims (4)

Producing a bottomed cylindrical case body with a bottom on the opposite side of the opening and the opening, and a pair of through holes formed in the bottom,
An electrode body including a positive electrode terminal and a negative electrode terminal is accommodated in the case body,
Among the pair of through holes, the positive terminal is inserted into one through hole and the negative terminal is inserted into the other through hole,
In a manufacturing method of a sealed battery in which a lid covering the opening is joined to the case body by welding,
A guide rod is coaxially connected to the positive terminal and the negative terminal,
While inserting the guide rod connected to the positive terminal into the one through hole,
Inserting the guide rod connected to the negative terminal into the other through hole,
A method for producing a sealed battery, wherein the electrode body is accommodated in the case body. The positive terminal and the negative terminal have bolt holes,
2. The method of manufacturing a sealed battery according to claim 1, wherein the guide rod includes a bolt shaft portion that is screwed into the bolt hole at a connection side end portion.   The method for manufacturing a sealed battery according to claim 1, wherein the guide rod includes a reduced diameter portion that decreases in diameter toward a distal end side. A bottomed cylindrical case body having an opening and a bottom on the opposite side of the opening, and a pair of through holes formed in the bottom;
An electrode body comprising a positive electrode terminal and a negative electrode terminal, and housed in the case main body;
A sealed battery comprising: a cover that covers the opening and is joined to the case main body by welding;
The positive terminal and the negative terminal each have a bolt hole,
The sealed battery according to claim 1, wherein the bolt hole is capable of screwing a bolt shaft provided at a connecting side end portion of a guide rod that can be coaxially connected to the positive terminal and the negative terminal.

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