JP5483457B2 - Battery, battery container and manufacturing method - Google Patents

Description

  The present invention relates to a battery housing container for housing a power generation element such as a battery or a battery element, and a manufacturing method.

  Conventionally, as this type of technology, for example, Patent Document 1 discloses that a thin square battery is accommodated between an upper cup formed into a half-shell and a lower cup that seals the opening. The technology is described.

  Patent Document 2 describes a technique related to a rectangular battery can that accommodates a thin rectangular battery. A rectangular cylindrical element (square cylinder) and a bottom plate are separately formed, A technique is described in which a bottom plate is joined to the end face of a tube by laser welding.

  Patent Document 3 describes a technique related to a rectangular battery can that accommodates a thin rectangular lithium ion secondary battery. In this technique, press molding is performed in multiple steps from an elliptical blank (material). After that, a technique for forming a rectangular tube is described.

JP 2001-250517 A JP-A-6-333541 JP 2003-157809 A

  Here, since the technique described in Patent Document 1 can be molded by shallow drawing, the molding is easy and the quality can be stabilized.

  However, in the technique described in Patent Document 1, the upper cup and the lower cup are joined by welding, but the welded portion extends around the entire circumference of the joined portion of the upper cup and the lower cup, so that the weld length is long and the productivity is increased. May be inferior.

  Moreover, since the technique described in Patent Document 2 can omit deep drawing, it is easy to form and can stabilize quality.

  However, the technique described in Patent Document 2 requires that the two parts (the square tube and the bottom plate) for joining the thin prismatic battery be accurately maintained while being pressed, which complicates the work. There is a risk of complicating the apparatus. Moreover, since it is necessary for the laser to relatively move around the joint portion (around the square tube), the welding length becomes long, and the welding speed needs to be slowed at the corner portion, so that the productivity may be inferior.

  In addition, the technique described in Patent Document 3 can reduce the thickness and weight, but since it is formed into a rectangular tube through a plurality of steps from an elliptical blank (material), it is difficult to form with a plurality of molds. There is a risk that the cost may increase and productivity may be inferior.

  In addition, as described in Patent Document 3, a square battery can is also formed by a DI (Drawing and Ironing) method (Shigoki drawing method), but this DI method is used in cylindrical molding. There is no problem because it is squeezed by two times of drawing, but it is not suitable for forming a shape that requires a deep drawing because it will be formed into a final square tube with two times of drawing. .

  Furthermore, although it is envisaged to form a rectangular battery can by impact molding, impact molding can be formed into a square tube in one step, but the side wall thickness varies because it is a single extrusion. In addition, it is difficult to reduce the thickness of the side wall and the wall thickness is increased, which may result in poor material yield and difficult quality control.

  In addition, when deep drawing is performed by press molding, since strong processing is performed, work hardening is intense, and when stainless steel is used as a material, annealing is generally performed, which increases processing time. There is a fact that it is difficult to improve productivity.

  The present invention has been made in view of such circumstances, and is a battery and a battery that are simple and low cost, have excellent productivity, stable quality, good yield, and satisfy predetermined strength, rigidity, and the like. It is an object to provide a container and a manufacturing method.

Therefore, the battery according to the present invention is
A battery configured to include a battery container that houses a power generation element,
The battery container is
A bottom formed in a concave shape without joints,
A plurality of side walls continuous from the bottom;
Have
Adjacent portions of the plurality of side wall portions are joined.

  In the present invention, the bottom portion may be formed by press molding.

  In the present invention, the plurality of side wall portions continuous from the bottom portion may be bent around the vicinity of the connection portion with the bottom portion.

  In the present invention, joining of the adjacent portions of the plurality of side wall portions may be performed by welding.

Moreover, the battery container according to the present invention is:
A battery container that houses a power generation element,
A bottom formed in a concave shape without joints,
A plurality of side walls continuous from the bottom;
Have
Adjacent portions of the plurality of side wall portions are joined.

In addition, a method for manufacturing a battery container according to the present invention includes:
A method of manufacturing a battery container for housing a power generation element,
A plate-shaped material having a portion to be molded at the bottom of the battery container and a plurality of side walls that are continuous from the bottom to form a plurality of side walls is drawn to form a seamless concave bottom. And steps to
Bending a plurality of side wall portions around the connection portion with the bottom portion;
Joining adjacent portions of the plurality of side wall portions;
It is characterized by including.

  In the present invention, each step may be performed continuously in one press machine.

  The present invention has been made in view of such circumstances, and is a simple and low-cost battery that is excellent in productivity, stable in product quality, good in yield, can satisfy predetermined strength, rigidity, and the like. It aims at providing a battery storage container and a manufacturing method.

It is a perspective view which shows an example of the plate-shaped blank (material) used for manufacture of the battery storage container (battery) which concerns on one embodiment of this invention. It is a perspective view which shows the state which press-molded the bottom part from the state of FIG. It is the perspective view which extracted and showed the state which bent the side wall part by the bending process from the state of FIG. 2, and was shape | molded in the bottomed square tube shape. It is the perspective view which has the partial cross section which showed the state of FIG. 3 including the press die and the laser welding machine. FIG. 4 is a perspective view showing a state in which the vicinity of the upper end is excised after welding is performed on adjacent side wall portions from the state of FIG. 3. It is a figure for defining the shallow drawing depth (height) h in this invention. It is a perspective view which expands and shows a part of battery storage container in order to explain the clearance gap which may arise between adjacent side wall parts. (A) is a perspective view which shows another example of a blank (raw material), (B) is a perspective view which shows the state which shape | molded (A) in the shape of a bottomed square tube. (A) is a perspective view which shows another example of a blank (raw material), (B) is a perspective view which shows the state which shape | molded (A) in the shape of a bottomed square tube.

Hereinafter, a battery container (battery) and a manufacturing method according to an embodiment of the present invention will be described with reference to the accompanying drawings. By the way, in the present embodiment, in consideration of the fact that a power generation element (battery element (primary battery, secondary battery, etc.)) is housed in the battery housing container is treated as a battery, the battery housing container (battery ).
The present invention is not limited to the embodiments described below.

  In the battery container (battery) and the manufacturing method according to the present embodiment, as shown in FIG. 1, by drawing from a single blank (plate material) 1, a battery as shown in FIG. The concave bottom portion 11 of the storage container is formed.

  Since the bottom 11 is formed by shallow drawing, it can be formed without lubrication using a mold having a relatively simple structure, and can be stably formed. Fewer products can be provided, which can contribute to improvements in production costs and productivity.

  Next, from the state of FIG. 2, four cross-shaped side wall portions 12A, 12B, 12C, and 12D of the blank 1 that are continuous on the four sides of the bottom portion 11 are raised by bending, and the state as shown in FIG. To form.

  That is, the blank 1 is formed in a rectangular tube case shape with an open upper end as shown in FIG. 3, and is held in the mold of the servo press in this state. Note that the adjacent four pieces 12A, 12B, 12C, and 12D are not joined to each other.

  Since the blank 1 molded in the state of FIG. 3 is held in the mold as shown in FIG. 4, in this embodiment, the unjoined portions 13A, 13B, 13C, 13D (4 Positioning and pressing of the parts to be joined by welding or the like can be easily and accurately performed on the side wall portions 12A, 12B, 12C, and 12D.

  In the present embodiment, four corners (four sides) 13A, 13B, 13C, 13D of the blank 1 held in the mold (mutually adjacent portions of the four side wall portions 12A, 12B, 12C, 12D). The four corners (the four adjacent side walls 12A, 12B, 12C, and 12D) are joined by welding with a laser welding machine 50 for welding the two.

  The laser welding machine 50 is not limited to each of the four corners, and one or a plurality of laser welding machines 50 are moved between the corners so that the four corners 13A, 13B, 13C, It can also be set as the structure which joins 13D (Mutually adjacent part of 4 piece side wall part 12A, 12B, 12C, 12D) by welding.

  Then, as shown in FIG. 5, an unnecessary part is cut by the 1st cut process and the 2nd cut process, and the battery accommodating part 10 of a battery accommodating container is completed.

  In addition, after inserting a power generation element (battery element (primary battery, secondary battery, etc.)) (not shown) inside the battery housing part 10, an upper lid (not shown) is placed above the battery housing part 10 by welding or the like. The battery container and the battery are completed.

  As described above, in the present embodiment, it is not necessary to perform welding other than the welding process shown in FIGS. 3 and 4 except when the upper lid is attached, so that the member is positioned and held for welding. It is economical because it can reduce the number of jigs, etc. compared to the conventional one. In addition, it does not require time to set a blank to the jig for welding or to release the blank from the jig after welding. Can be improved.

  Further, in the present embodiment, simultaneously with the bending process from the state of FIG. 2 to the state of FIG. 3, four corner portions (four sides) 13A, 13B, 13C, 13D (four pieces of side wall portions 12A, 12B, 12C and 12D can be welded to each other), but in such a case, the blank 1 is firmly positioned by the mold, so that extremely high positioning accuracy can be achieved without a separate positioning tool. Can be realized. For this reason, the yield can be improved and it can contribute to quality improvement of a product, and it can also contribute to improvement of productivity.

  In the present embodiment, four laser welding machines 50 are provided corresponding to the four corner portions 13A, 13B, 13C, and 13D, but the welding length is near the upper end of the concave bottom portion 11 (in the middle of the four sides). Since the length of the side extending from (part) is shorter than the product height, the welding length can be shortened.

  Further, in the present embodiment, it is not necessary to weld along a corner such as the R portion (a portion that needs to be changed in the direction in which the laser irradiation axes intersect before and after (r direction in FIG. 4)). Therefore, it can be manufactured only by linear welding along the side, the welding speed can be increased while maintaining the quality at a predetermined level, and the productivity can be improved.

  In the present embodiment, when welding by the laser welding machine 50, the press machine is stopped and the laser welding machine 50 side is moved along the four corners (four sides) 13A, 13B, 13C, 13D. However, if a servo press machine is used, the laser welder side is held at a fixed position, and the slide (die) of the servo press machine is extended and the blank 1 side is moved. It is also possible to adjust the speed to the welding speed.

  As described above, when the laser welding machine side is held in place and the blank 1 side (sliding side of the servo press machine) is moved, the apparatus for moving the laser welding machine 50 can be omitted. Therefore, simplification of the configuration and cost reduction can be promoted.

  In the present embodiment, the side wall portions 12A, 12B, 12C, and 12D of the battery container are formed by bending, so that there are few restrictions on the product height direction in processing, and drawing processing for forming the side wall portion. Therefore, the four side walls can be formed with the blank 1 as it is.

  For this reason, since a battery housing container with high plate thickness accuracy can be easily manufactured, the breaking strength of the battery housing container can be set to a predetermined level or more while being low in cost, and variations in the thickness of the side wall etc. Therefore, when performing welding between the side walls, it is not necessary to make fine adjustments in consideration of variations in plate thickness (thermal capacity variation), and the welding operation can be facilitated. , It can be excellent in finished quality.

  Further, the upper lid joined to the four side wall portions is also manufactured by punching or the like from the same material (plate material) as the blank (material) 1 so that the thickness is equal to the plate thickness of the side wall portions 12A, 12B, 12C, 12D. Therefore, it is not necessary to make fine adjustments in consideration of variations in plate thickness (variations in heat capacity), etc., and welding between the top lid and the side wall can be facilitated. Therefore, it is possible to realize a high-quality weld joint with little variation.

  Further, in the present embodiment, since strong processing such as deep drawing is not required, work hardening does not occur, and even in the case of a stainless material, heat treatment that requires time such as annealing can be omitted. Production cost and productivity can be improved.

Here, Example 1 according to the present embodiment will be described.
Example 1 employs SUS430 as a blank (material) 1 material, and press machine “blanking” (see FIG. 1) → “drawing” (see FIG. 2) → “bending and welding” (FIG. 3, (See FIG. 4) → “Opening first cut” (see FIG. 5) → “Opening second cut” (see FIG. 5) to produce a battery container and a battery.

  Since drawing (Figure 2) is shallow drawing, it is possible to mold without lubrication using a mold with a relatively simple structure, and because the molding is stable, we provide products with little quality variation. This can contribute to improvements in production costs and productivity.

  After that, as described above, the four side wall portions 12A, 12B, 12C, and 12D are raised by bending and formed into a state as shown in FIG. 3, and the servo press is turned into a state as shown in FIG. Hold in the mold. Therefore, it is easy and accurate to position and press the parts to be joined by welding or the like at the parts 13A, 13B, 13C, 13D that are not joined (four side wall parts 12A, 12B, 12C, 12D, etc.). Could be done.

  In Example 1, laser welding was performed on the four corners (four sides) 13A, 13B, 13C, and 13D of the blank 1 held in the mold in this way by the laser welding machine 50.

Four laser welding machines 50 are arranged corresponding to the four corners, and the welding length of each laser welding machine 50 is 140 mm.
Since the welding in Example 1 was a straight line, the welding was simple and the required time was within 3 seconds (sec).

  Further, since the side wall portions 12A, 12B, 12C, and 12D are not subjected to drawing or the like, the side wall portions 12A, 12B, 12C, and 12D have an equal plate thickness, so that welding is easy.

  Furthermore, since the upper lid can be made of the same material (plate material) as the blank (material) 1, the thickness can be equal to the thickness of the side walls 12A, 12B, 12C, 12D. Welding was easy, and there was no problem such that one of them melted, and it was possible to realize high-quality welded joints with little variation.

  In addition, in a destructive test of a battery (battery container) manufactured by welding a top cover after inserting a power generation element (battery element (primary battery, secondary battery, etc.)), the entire battery container is almost the same. Since the thickness was uniform, there was no variation in the results of the destructive test.

  Further, since there is no deep drawing, work hardening does not occur, so the low temperature brittleness unique to SUS430 is improved, and the fracture test can be cleared even in the low temperature brittleness test.

Next, Example 2 will be described.
Example 2 employs SUS304 as a blank (material) 1 material, and press machine “blanking” (see FIG. 1) → “drawing” (see FIG. 2) → “bending and welding” (FIG. 3, (See FIG. 4) → “Opening first cut” (see FIG. 5) → “Opening second cut” (see FIG. 5) to produce a battery container and a battery.

  Also in Example 2, since the drawing (FIG. 2) is shallow drawing, it is possible to mold without lubrication with a mold having a relatively simple structure, and the molding is stable. Products with little variation can be provided, which can contribute to improvements in production costs and productivity.

  Thereafter, similarly in the second embodiment, the four side wall portions 12A, 12B, 12C, and 12D are raised by bending, formed into a state as shown in FIG. 3, and servoed into a state as shown in FIG. Hold in the press mold. Therefore, it is easy and accurate to position and press the parts to be joined by welding or the like at the parts 13A, 13B, 13C, 13D that are not joined (four side wall parts 12A, 12B, 12C, 12D, etc.). Could be done.

  In the second embodiment, the four corners (four sides) 13A, 13B, 13C, 13D (four pieces of side walls 12A, 12B, 12C, 12D) of the blank 1 held in the mold as described above are used. Laser welding was performed on the adjacent part) with a laser welding machine 50.

Four laser welding machines 50 are arranged corresponding to the four corners, and the welding length of each laser welding machine 50 is 140 mm.
Since the welding in Example 2 was a straight line, the welding was simple and the required time was within 3 seconds (sec).

  Further, since the side wall portions 12A, 12B, 12C, and 12D are not subjected to drawing or the like, the side wall portions 12A, 12B, 12C, and 12D have an equal plate thickness, so that welding is easy.

  Moreover, since the top lid can be made of the same material (plate material) as the blank (material) 1, it can be made equal to the thickness of the side wall portions 12A, 12B, 12C, 12D, so that welding is easy. We were able to realize high-quality welded joints with little variation, with no defects such as melting.

  In addition, in a destructive test of a battery (battery container) manufactured by welding a top cover after inserting a power generation element (battery element (primary battery, secondary battery, etc.)), the entire battery container is almost the same. Since the thickness was uniform, there was no variation in the results of the destructive test.

  In addition, since there is no deep drawing, work hardening does not occur, so the time cracking peculiar to SUS304 was improved, and the destructive test could be cleared even in the time cracking test.

Next, Example 3 will be described.
Example 3 employs an aluminum alloy (A3003) as the material of the blank (material) 1 and presses “blanking” (see FIG. 1) → “drawing” (see FIG. 2) → “bending and welding” with a press machine. (Refer to FIG. 3) → “Opening first cut” (see FIG. 4) → “Opening second cut” (see FIG. 4) to manufacture a battery housing container and a battery.

  Even when the aluminum alloy as in Example 3 is used as the raw material, the drawing (FIG. 2) is shallow drawing, so that it can be formed without lubrication by a mold having a relatively simple structure. Since the molding is stable, it is possible to provide products with little quality variation and contribute to improvements in production cost and productivity.

  Thereafter, similarly in the third embodiment, the four side wall portions 12A, 12B, 12C, and 12D are raised by bending to form the state as shown in FIG. 3, and the servo is brought into the state as shown in FIG. Hold in the press mold. Therefore, it is easy and accurate to position and press the parts to be joined by welding or the like at the parts 13A, 13B, 13C, 13D that are not joined (four side wall parts 12A, 12B, 12C, 12D, etc.). Could be done.

  In Example 3, the four corners (four sides) 13A, 13B, 13C, and 13D (four pieces of side walls 12A, 12B, 12C, and 12D of the blank 1 held in the mold in this way are mutually connected. Laser welding was performed on the adjacent part) with a laser welding machine 50.

Four laser welding machines 50 are arranged corresponding to the four corners, and the welding length of each laser welding machine 50 is 140 mm.
Since the welding in Example 2 was a straight line, the welding was simple and the required time was within 3 seconds (sec).

  Further, since the side wall portions 12A, 12B, 12C, and 12D are not subjected to drawing or the like, the side wall portions 12A, 12B, 12C, and 12D have an equal plate thickness, so that welding is easy.

  Moreover, since the top lid can be made of the same material (plate material) as the blank (material) 1, it can be made equal to the thickness of the side wall portions 12A, 12B, 12C, 12D, so that welding is easy. We were able to realize high-quality welded joints with little variation, with no defects such as melting.

  In addition, in a destructive test of a battery (battery container) manufactured by welding a top cover after inserting a power generation element (battery element (primary battery, secondary battery, etc.)), the entire battery container is almost the same. Since the thickness was uniform, there was no variation in the results of the destructive test.

Here, in this Embodiment, it defines as follows as an example of the shallow drawing forming of this invention.
That is, referring to FIG.
h: Drawing depth (height) (mm)
R: R dimension outside product (mm)
t: Material plate thickness (mm)
When
Drawing at a drawing depth (height) h (mm) that satisfies R + 2t <h <15 is defined as shallow drawing.

If the drawing depth (height) is not secured for the outer R portion of the product, the laser welding machine must be moved in the θ direction (see FIG. 6: the direction in which the laser irradiation axes intersect). It becomes inefficient.
In addition, the R part is a free part that is not molded by a mold during pressing, and the shape is slightly different for each molding and is not a stable shape. Quality is not stable.
Therefore, it is desirable to avoid welding to the R portion.

Further, when R + 2t ≧ h, as shown in FIG. 7, the joint of the side wall portion after drawing is not well matched, and a gap may be generated.
For this reason, in this embodiment, the depth (height) h of the shallow diaphragm is set to R + 2t <h.

  On the other hand, if h ≧ 15, the drawing becomes deep, and it becomes necessary to use a lubricant during drawing. In such a case, it is necessary to perform a process such as cleaning in the subsequent process, and then the laser welding process. Since the process cannot be performed, the process becomes complicated and redundant, and a detergent and a cleaning time are required. Therefore, there are many disadvantages in terms of production cost and productivity.

  For this reason, in this embodiment, a diaphragm in which the diaphragm depth (height) h falls within the range of R + 2t <h <15 is defined as a shallow diaphragm.

  As an example, the material thickness t is about 0.80 to 1.2 mm in the case of aluminum, about 0.5 to 0.8 mm in the case of SUS, and R is about 6 mm, for example. Is assumed.

  By the way, in this Embodiment mentioned above, as shown in FIG. 4, four corner | angular part (four sides) 13A, 13B, 13C, 13D (four pieces side wall) of the blank 1 hold | maintained in the metal mold | die are shown. The portions adjacent to the portions 12A, 12B, 12C, and 12D have been described as being welded and joined by the laser welding machine 50, but are not limited thereto.

  For example, as shown in FIGS. 8 and 9, four pieces (side walls) 12a (12a ′), 12b (12b ′), 12c (12c ′), and 12d (12d ′) are illustrated in FIG. The rectangular shape can be changed to another shape. Correspondingly, it is possible to change the shape of the outer mold of the blank 1 in order to pass the laser for welding, or to change the laser welding machine for welding the joint.

  As shown in FIG. 8 and FIG. 9, for example, by bringing the joint (welded part) to the flat surface, the joining process is facilitated, and improvement in productivity and quality can be expected.

  As described above, according to the battery container (battery) and the manufacturing method according to the present embodiment, the bottom portion is formed without lubrication by a shallow drawing with a small processing load, and continuous to the bottom portion that is seamlessly formed. Each piece to be bent is bent almost vertically by bending with a small processing load and formed into a cylindrical box shape, and the state is maintained by, for example, a mold, so that adjacent portions of each piece are joined by welding while accurately positioning. As described above, it is possible to manufacture a battery housing container (battery) having a high level and a stable quality while being simple and low cost and having excellent productivity.

  In particular, according to the battery container (battery) and the manufacturing method according to the present embodiment, since drawing processing or the like is not performed on the portion to be welded, the thickness of the material to be welded is the thickness of the raw material as it is. Therefore, it is possible to improve the productivity because the welding operation is easy and the occurrence of defects due to the non-uniform thickness in the portion to be welded and joined together can be suppressed. In addition, it is possible to improve the quality of the welding and thus the product quality.

  Further, according to the battery container (battery) and the manufacturing method according to the present embodiment, since the drawing is not performed on the side wall portion, the plate thickness can be left as it is, so that the battery element or the like After the power generation element is accommodated, the upper lid that covers the upper portion of the side wall can be manufactured with the same thickness as the side wall. Since generation | occurrence | production of this can be suppressed, while being able to improve productivity, the quality of welding and the product quality can be improved.

  Furthermore, according to the battery container (battery) and the manufacturing method according to the present embodiment, since processing with a large load such as deep drawing is not included, work hardening does not occur. For example, heat treatment such as annealing. Even when SUS430 is used as a raw material, the low temperature brittleness specific to SUS430 can be improved, and even when SUS304 is used as a raw material, the time crack specific to SUS304 can be improved.

  In addition, in this Embodiment mentioned above, although laser welding was illustrated and demonstrated, while it is not limited to this, The kind of raw material can employ | adopt an appropriate welding method according to a dimension etc. It is also possible to employ a joining method other than welding.

  The embodiments according to the present invention described above are merely examples for explaining the present invention, and various modifications can be made without departing from the gist of the present invention.

  The present invention provides a battery container (battery) and a manufacturing method that are simple and low-cost, that are excellent in productivity, stable in quality, have good yield, can satisfy predetermined strength, rigidity, and the like. For example, in the field of battery manufacturing technology.

1 Material (blank)
DESCRIPTION OF SYMBOLS 10 Battery accommodating part 11 Bottom part 12A-12D Side wall part 12a-12d Side wall part 12a'-12d 'Side wall part 13A-13D Corner | angular part (side)
50 Laser welding machine

Claims (7)

A battery configured to include a battery container that houses a power generation element,
The battery container is
A bottom formed in a concave shape without joints,
A plurality of side walls continuous from the bottom;
Have
A battery characterized in that adjacent portions of a plurality of side wall portions are joined. The battery according to claim 1, wherein the bottom portion is formed by press molding. 3. The battery according to claim 1, wherein the plurality of side wall portions continuous from the bottom portion are bent around the vicinity of the connection portion with the bottom portion. The battery according to claim 1, wherein joining of adjacent portions of the plurality of side wall portions is performed by welding. A battery container that houses a power generation element,
A bottom formed in a concave shape without joints,
A plurality of side walls continuous from the bottom;
Have
A battery housing container in which adjacent portions of a plurality of side wall portions are joined. A method of manufacturing a battery container for housing a power generation element,
A plate-shaped material having a portion to be molded at the bottom of the battery container and a plurality of side walls that are continuous from the bottom to form a plurality of side walls is drawn to form a seamless concave bottom. And steps to
Bending a plurality of side wall portions around the connection portion with the bottom portion;
Joining adjacent portions of the plurality of side wall portions;
The manufacturing method of the battery container characterized by including. The method for manufacturing a battery container according to claim 6, wherein each step is continuously performed in one press machine.