JP2019057421A - Secondary battery - Google Patents

Abstract

To surely block a liquid pouring hole until a liquid pouring step and furthermore to easily expose the liquid pouring hole in the liquid pouring step.SOLUTION: A secondary battery 1 comprises: a case body 3; an electrode body 2 housed inside the case body 3; an upper surface member 16 that is provided in an upper part of the case body 3, and has a liquid pouring hole 24 and a lid part 22 provided so as to block the liquid pouring hole 24. A concave part 26 is provided in the upper surface member 16. In the concave part 26, the liquid pouring hole 24 is formed in a bottom surface, and the cover part is formed movably between a first position blocking the liquid pouring hole 24 and a second position where the lid part 22 is separated from the liquid pouring hole 24. A slide surface in the bottom surface of the concave part 26 is inclined so that the first position becomes lower than the second position, the bottom surface of the concave part and the lid part 22 sliding each other on the slide surface.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a secondary battery.

  In the manufacturing process of a power storage device such as a secondary battery, a lid material is welded to the upper surface of a metal outer case, and an electrolytic solution is injected from a liquid injection port provided in the lid material in a state where the electrode body is accommodated. A liquid injection process is provided.

  Regarding the manufacturing process of such a secondary battery, for example, Japanese Patent Laying-Open No. 2017-117657 (Patent Document 1) describes a cap until a liquid injection process for injecting an electrolyte into a battery outer case is performed. A technique is disclosed in which a liquid injection port is closed using a magnet and fixed with a magnet.

JP 2017-117657 A

  However, depending on the manufacturing process of the secondary battery, the magnet for fixing the cap may be removed, and the cap may be removed from the liquid injection port during the period when the magnet is removed. On the other hand, it is possible to close the injection port without a magnet by strengthening the connection between the cap and the injection port, but it is not possible to easily remove the cap in the injection process There is.

  The present disclosure has been made in order to solve the above-described problems, and the object thereof is to easily expose the liquid injection port in the liquid injection step while reliably closing the liquid injection port until the liquid injection step. Is to provide a secondary battery capable of

  A secondary battery according to an aspect of the present disclosure includes an outer case, an electrode body housed in the outer case, and a lid provided on an upper portion of the outer case so as to close the liquid inlet and the liquid inlet. And an upper surface member provided with a portion. The upper surface member is provided with a recess. The recess is formed such that a liquid injection port is formed on the bottom surface, and is movable between a first position where the lid portion closes the liquid injection port and a second position where the lid portion is separated from the liquid injection port. The The sliding surface with the lid on the bottom surface of the recess is inclined so that the first position is lower than the second position.

  If it does in this way, since the sliding surface with the cover part in the bottom of a crevice inclines so that the 1st position may become lower than the 2nd position, the position of a cover part is the 1st position, for example. In this case, the movement of the lid portion to the second position can be suppressed by its own weight. On the other hand, at the time of liquid injection, the liquid injection port can be easily exposed by moving the position of the lid to the second position.

  According to the present disclosure, it is possible to provide a secondary battery capable of easily exposing the liquid injection port in the liquid injection process while reliably closing the liquid injection port until the liquid injection process.

It is the front view which shows a secondary battery, Comprising: It is the front view seen partially in cross section. It is an enlarged view of the broken line frame of FIG. It is a perspective view of an upper surface member in case a cover part is the 1st position. It is a figure which shows a sliding surface with the bottom face of the recessed part of the back side of a cover part. It is the figure which looked at the injection part in case the cover part is a 2nd position in cross section. It is a perspective view of an upper surface member in case a cover part is the 2nd position. It is a manufacturing flowchart which shows the manufacturing process of a secondary battery. It is a front view which shows upper surface unit assembly process S1. It is a front view which shows electrode body connection process S2. It is a front view which shows accommodation process S3. It is a front view which shows welding process S4. It is a front view which shows liquid injection process S5. It is a front view which shows sealing process S6. It is the figure which looked at the injection part in case the cover part in a modification is a 1st position in cross section. It is the figure which looked at the liquid injection part in case the cover part in a modification is a 2nd position in cross section.

  Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

  FIG. 1 is a front view showing a secondary battery 1, and is a front view partially in cross section. The secondary battery 1 includes an electrode body 2, a housing case 3, a positive electrode current collector terminal 4, a negative electrode current collector terminal 5, an electrolyte solution 6, a positive electrode external terminal 7, a negative electrode external terminal 8, and a liquid injection part 20 and so on.

  The electrode body 2 is formed by winding in a state in which the positive electrode sheet 10, the separator 11, and the negative electrode sheet 12 are laminated. The electrode body 2 is formed in a flat shape. The electrode body 2 includes a positive electrode 13 and a negative electrode 14.

  The housing case 3 includes a case body 15 that is an exterior case, and an upper surface member 16. The case main body 15 has an opening that opens upward. The upper surface member 16 is disposed so as to close the opening above the case body 15. The outer peripheral edge of the upper surface member 16 is welded to the opening edge of the opening of the case body 15. The housing case 3 is made of, for example, aluminum or an aluminum alloy.

  In the manufacturing process of the secondary battery 1 as described above, the upper surface member 16 is welded to the case body, and the electrolytic solution is injected from the injection portion 20 provided on the upper surface member 16 in a state where the electrode body is accommodated. A liquid process is provided.

  With respect to the manufacturing process of such a secondary battery, for example, an opening of the liquid injection part 20 using a cap is performed until the liquid injection process of injecting the electrolyte into the housing case 3 of the secondary battery 1 is performed. It is conceivable to close the (liquid injection port) and fix it with a magnet.

  However, depending on the manufacturing process of the secondary battery 1, the magnet for fixing the cap may be removed, and the cap may be detached from the liquid injection part 20 during the period when the magnet is removed. On the other hand, by strengthening the connection between the cap and the liquid injection part 20 by changing the material and dimensions of the cap, it is possible to close the liquid injection port without a magnet. There is a case where the work of removing from the liquid injection part 20 cannot be easily performed.

  Therefore, in the present embodiment, the top member 16 is provided with a lid and a recess. The recess is movable between a first position where a liquid inlet is formed on the bottom surface and the lid closes the liquid inlet and a second position where the lid is separated from the liquid inlet. It is formed. The sliding surface with the lid on the bottom surface of the recess is inclined such that the first position is lower than the second position.

  If it does in this way, since the sliding surface with the cover part in the bottom of a crevice inclines so that the 1st position may become lower than the 2nd position, the position of a cover part is the 1st position, for example. In this case, the movement of the lid portion to the second position can be suppressed by its own weight. On the other hand, at the time of liquid injection, the liquid injection port can be easily exposed by the operator moving the position of the lid to the second position.

  Hereinafter, such a structure will be described in detail with reference to FIGS. FIG. 2 is an enlarged view of a broken-line frame in FIG. FIG. 3 is a perspective view of the upper surface member 16 when the lid portion 22 is in the first position.

  As shown in FIG. 2, the liquid injection part 20 includes a lid part 22 and a concave part 26. A liquid injection port 24 is formed on the bottom surface of the recess 26. The concave portion 26 is well known so that the lid portion 22 can move between a first position where the lid portion 22 closes the liquid injection port 24 and a second position where the lid portion 22 is separated from the liquid injection port 24. It is formed using a processing method. In FIG. 2, the structure of the liquid injection part 20 in the case where the lid part 22 is at the first position for closing the liquid injection port 24 is shown. As shown in FIG. 2, the sliding surface with the lid portion 22 on the bottom surface of the concave portion 26 is inclined so that the first position is lower than the second position. The bottom surface of the lid portion 22 (the contact surface with the bottom surface of the concave portion 26) is inclined in the same manner as the bottom surface of the concave portion 26. When the position of the lid portion 22 is the first position, the top surface and the top surface of the lid portion 22 The upper surface of the member 16 is substantially in the same plane. A predetermined groove portion 28 is formed on the bottom surface side of the lid portion 22.

  As shown in FIG. 3, the lid portion 22 has a substantially rectangular shape when viewed from above. The end surface in the width direction of the lid portion 22 is provided so as to abut against the inner wall of the recess 26 or have a predetermined gap. The length of the concave portion 26 in the horizontal direction of the paper surface is formed to be longer than the length of the lid portion 22 in the horizontal direction of the paper surface. As a result, the lid 22 can slide in the lateral direction of the paper in a state where it is housed in the recess 26. In FIG. 3, the case where the lid portion 22 is in the first position is shown, and the liquid injection port 24 formed on the bottom surface of the concave portion 26 is closed by the lid portion 22.

  FIG. 4 is a view showing a sliding surface with the bottom surface of the concave portion 26 on the back side of the lid portion 22. As shown in FIG. 4, a groove portion 28 is formed on the sliding surface of the lid portion 22 with the bottom surface of the concave portion 26 from an intermediate position of the end portion in the longitudinal direction of the lid portion 22 to the vicinity of the center of the lid portion 22. The groove part 28 is formed so that the liquid injection port 24 and the end part in the longitudinal direction of the groove part 28 communicate with each other when the lid part 22 is in the first position.

  FIG. 5 is a cross-sectional view of the liquid injection part 20 when the lid part 22 is in the second position. FIG. 6 is a perspective view of the upper surface member 16 when the lid portion 22 is in the second position.

  As shown in FIGS. 5 and 6, for example, when the lid portion 22 is moved to the second position along the longitudinal direction of the recess 26 from the first position, the lid portion 22 is The position is separated from the liquid port 24. Thereby, the upper part of the liquid injection port 24 is opened, and the liquid injection port 24 is exposed. As a result, the electrolyte can be injected from above.

  A method for manufacturing the secondary battery 1 configured as described above will be described in detail. FIG. 7 is a manufacturing flowchart showing the manufacturing process of the secondary battery 1. The manufacturing process of the secondary battery 1 includes an upper surface unit assembly process S1, an electrode body connection process S2, a housing process S3, a welding process S4, a liquid injection process S5, and a sealing process S6.

  FIG. 8 is a front view showing the upper unit assembly process S1. In the upper surface unit assembly step S1, the positive electrode current collector terminal 4, the negative electrode current collector terminal 5, the positive electrode external terminal 7, the negative electrode external terminal 8, and the lid portion 22 are assembled to the upper surface member 16, and the upper surface unit 75 is assembled. Form. At this time, the lid portion 22 is moved to the first position. Thereby, mixing of the foreign material via the pouring port 24 is prevented until the pouring step S5.

  FIG. 9 is a front view showing the electrode body connection step S2. The electrode body connection step S <b> 2 is a step of welding the electrode body 2 to the upper surface unit 75. Specifically, it includes a step of welding the positive electrode current collector terminal 4 to the positive electrode 13 of the electrode body 2 and a step of welding the negative electrode current collector terminal 5 to the negative electrode 14 of the electrode body 2.

  FIG. 10 is a front view showing the housing step S3. In the housing step S3, the electrode body 2 welded to the upper surface unit 75 is housed in the case main body 15. In this step, the upper surface member 16 is disposed at the opening edge of the case body 15.

  FIG. 11 is a front view schematically showing the welding step S4. The welding step S4 is a step of welding the outer peripheral edge portion of the upper surface member 16 to the opening edge portion of the case body 15. In this step, the opening edge portion of the case body 15 and the outer peripheral edge portion of the upper surface member 16 are laser-welded in a state where the shield gas 77 is sprayed from the nozzle 76 toward the housing case 3. For example, nitrogen gas or the like can be used as the shield gas 77.

  FIG. 12 is a front view schematically showing the liquid injection step S5. The liquid injection step S <b> 5 is a step of injecting the electrolytic solution of the secondary battery 1 into the housing case 3. The liquid injection step S5 is a step of drying the inside of the storage case 3, a step of moving the lid portion 22 to the second position, and an electrolytic solution is injected into the storage case 3 via the exposed liquid injection port 24. And liquefying.

  In the step of drying the inside of the housing case 3, the lid portion 22 is in the first position to prevent foreign matter from entering, and the groove portion 28 provided on the back side of the lid portion 22 serves as an air passageway in the housing case 3. Promotes drying.

  In the step of injecting the electrolytic solution, the lid portion 22 is moved from the first position to the second position. As a result, the liquid injection port 24 is exposed, so that the electrolytic solution is injected through the liquid injection port 24. After the liquid injection process, the lid 22 is moved again from the second position to the first position. Thereby, mixing of the foreign material via the liquid injection port 24 after liquid injection can be prevented. Further, the gas generated from the electrolytic solution in the storage case 3 is discharged out of the storage case 3 via a groove portion 28 provided on the back side of the lid portion 22.

  FIG. 13 is a diagram illustrating the sealing step S6. The sealing step S6 is a step of sealing the housing case 3. The sealing step S6 includes a step of moving the lid portion 22 to the first position and a step of welding the entire circumference (including the end portion of the groove portion 28) of the lid portion 22 in a state where the liquid injection port 24 is closed. Including. By welding the entire periphery of the lid portion 22 at the first position, the liquid injection port 24 is closed, and the housing case 3 is sealed.

  As described above, according to the secondary battery 1 according to the present embodiment, the sliding surface of the bottom surface of the recess 26 with the lid portion 22 is inclined so that the first position is lower than the second position. Therefore, for example, when the position of the lid part 22 is the first position, the movement of the position of the lid part 22 to the second position can be suppressed by its own weight. On the other hand, at the time of liquid injection, the liquid injection port 24 can be easily exposed by moving the position of the lid portion 22 to the second position. Therefore, it is possible to provide a secondary battery in which the liquid injection port can be easily exposed in the liquid injection process while the liquid injection port is reliably closed until the liquid injection process.

  For example, when a cap for closing the liquid injection port 24 is used repeatedly, if foreign matter remains in the cap due to insufficient cleaning in the cleaning process for reusing the cap, Although the foreign matter may be mixed in, the lid portion 22 in the present embodiment is not reused and is welded to the upper surface member 16 as a member constituting the housing case 3. It is possible to suppress contamination by foreign matter.

  Furthermore, an increase in the number of parts can be suppressed as compared with the case where the cap is reused, and an increase in manufacturing cost can be suppressed because it is not necessary to perform a process such as a cleaning process.

  Furthermore, since the cover part 22 can be accommodated in the recessed part 26, it can prevent that the cover part 22 falls from the upper surface member 16 in the manufacturing process of the secondary battery 1. FIG.

Hereinafter, modifications will be described.
In the above-described embodiment, the movement direction of the lid portion 22 has been described as the longitudinal direction of the recess portion 26. However, the recess portion 26 may be formed so that the lid portion 22 can move in the width direction.

  Furthermore, in the above-described embodiment, the first position on the sliding surface of the bottom surface of the concave portion 26 with the lid portion 22 is inclined more than the second position by inclining the bottom surface of the concave portion 26 with respect to the upper surface of the upper surface member 16. Although it is inclined so as to be lowered, it is not particularly limited to such a configuration.

  FIG. 14 is a cross-sectional view of the liquid injection part 20 when the lid part 22 in the modification is at the first position. FIG. 15 is a cross-sectional view of the liquid injection unit 20 when the lid 22 in the modification is in the second position.

  As shown in FIGS. 14 and 15, in this modification, a portion of the upper surface member 16 where the recess is provided may be inclined.

  Even in such a configuration, the sliding surface with the lid portion 22 on the bottom surface of the concave portion 26 is inclined so that the first position is lower than the second position. Therefore, when the position of the cover part 22 is a 1st position, it can suppress by the dead weight that the position of the cover part 22 moves to a 2nd position. On the other hand, at the time of liquid injection, the liquid injection port can be easily exposed by moving the lid portion 22 to the second position.

In addition, you may implement the above-mentioned modification combining all or one part suitably.
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present disclosure is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Secondary battery, 2 electrode body, 3 accommodation case, 4 positive electrode current collection terminal, 5 negative electrode current collection terminal, 6 electrolyte solution, 7 positive electrode external terminal, 8 negative electrode external terminal, 10 positive electrode sheet, 11 separator, 12 negative electrode sheet, 13 positive electrode, 14 negative electrode, 15 case main body, 16 upper surface member, 20 liquid injection part, 22 lid part, 24 liquid injection port, 26 concave part, 28 groove part, 75 upper surface unit, 76 nozzle, 77 shield gas.

Claims (1)

An exterior case,
An electrode body housed in the exterior case;
An upper surface member provided at an upper portion of the outer case, and provided with a liquid inlet and a lid portion provided so as to close the liquid inlet;
The upper surface member is provided with a recess,
The concave portion is formed between a first position where the liquid injection port is formed on a bottom surface and the lid portion closes the liquid injection port and a second position where the lid portion is separated from the liquid injection port. Is formed to be movable,
A secondary battery, wherein a sliding surface of the bottom surface of the concave portion with the lid portion is inclined so that the first position is lower than the second position.

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