Strut device for tabletop folding of secondary battery cells

Abstract

Disclosed is a strut device for tabletop folding of a secondary battery cell. The strut device supports a tabletop portion of the secondary battery cell in a direction opposite to the folding direction. The secondary battery cell includes an electrode stack portion in which electrodes are stacked, and a tabletop portion that is formed along the outer periphery of the electrode stack portion and a part of which is folded in the folding direction to face the electrode stack portion. The strut device includes an upper strut and a lower strut. The upper strut and the lower strut have the electrode stack portion at their rear portions in the folding direction, have a long length from one end to the other end of the secondary battery cell in a direction orthogonal to the folding direction, and face each other at the upper and lower sides of the tabletop portion to hold the tabletop portion. Among them, the upper strut and the lower strut are formed such that the thickness allowing the tabletop portion to be held in a region where the electrode stack portion is not arranged at the rear portion in the folding direction is greater than the thickness allowing the tabletop portion to be held in a region where the electrode stack portion is arranged at the rear portion in the folding direction.

Description

Technical Field

[0001] The present disclosure relates to a strut device for tabletop folding of a secondary battery cell, and more particularly, to a strut device for tabletop folding of a secondary battery cell that can prevent the occurrence of defects by restricting a wide area of the tabletop portion at a defect occurrence position where a tabletop deformation defect occurs. Background Art

[0002] This section provides background information related to the present disclosure, which is not necessarily prior art.

[0003] In the process of manufacturing a secondary battery cell, the process of folding the tabletop portion of the secondary battery cell is performed in a state where all components constituting the secondary battery are assembled.

[0004] In addition, the process of folding the tabletop portion needs to be precisely performed on a tabletop portion having a small area along the outer periphery of the electrode stack, and this process may be accompanied by a heat treatment process.

[0005] A general strut device for tabletop folding of a secondary battery cell, which is used for the process of folding the tabletop portion of the secondary battery cell, the strut device includes an upper strut and a lower strut.

[0006] During the general process of folding the tabletop portion of the secondary battery cell, the wide surface of the secondary battery cell is set to point upward / downward, the upper strut is disposed above the tabletop portion, and the lower strut is disposed below the tabletop portion.

[0007] The upper strut and the lower strut move upward or downward while facing each other and come into contact with the tabletop portion. The end of the tabletop portion is folded toward the upper strut by a folding press.

[0008] Since the tabletop portion is formed by bonding a soft bag for the secondary battery, the shape of the tabletop portion is likely to be accidentally deformed during the process of transmitting an unexpected external force.

[0009] In particular, if the tabletop portion not restricted by the upper strut and the lower strut is accidentally deformed, a fatal defect that affects the stability of the secondary battery cell may occur. Summary of the Invention

[0010] Technical Problem

[0011] An object of the present disclosure is to provide a strut device for tabletop folding of a secondary battery cell that can prevent deformation defects occurring at the end of the tabletop portion based on the longitudinal direction of the tabletop portion during the process of folding the tabletop portion of the secondary battery cell.

[0012] Technical Solution

[0013] This section provides a general inventive concept of the present disclosure, rather than a full disclosure of its entire scope or all of its features.

[0014] One aspect of the present disclosure provides a strut device for tabletop folding of a secondary battery cell. The strut device supports a tabletop portion of the secondary battery cell in a direction facing the folding direction. The secondary battery cell includes an electrode stack formed by stacking electrodes, and the tabletop portion is formed along an outer periphery of the electrode stack and has a portion that folds toward the electrode stack in the folding direction. The strut device includes: an upper strut and a lower strut. The upper strut and the lower strut are disposed in front of the electrode stack based on the folding direction and both extend to have a length from one end to the other end of the secondary battery cell in a direction orthogonal to the folding direction. The upper strut and the lower strut are disposed above and below the tabletop portion while facing each other and are configured to hold the tabletop portion. Among them, the upper strut and the lower strut are configured such that a thickness for holding the tabletop portion in a region where the electrode stack is disposed at a rear side based on the folding direction is greater than a thickness for holding the tabletop portion in a region where the electrode stack is not disposed at the rear side based on the folding direction.

[0015] In a strut device for tabletop folding of a secondary battery cell according to one aspect of the present disclosure, the upper strut may move upward or downward above the tabletop portion. The upper strut may be disposed between the electrode stack and the tabletop portion, and the upper strut may include: an upper inner portion on which the electrode stack is disposed in the folding direction; and upper outer portions respectively disposed at two opposite ends of the upper inner portion and extending farther than the upper inner portion in the folding direction, such that a thickness of the upper outer portion that comes into contact with the tabletop portion in the folding direction is greater than a thickness of the upper inner portion, and the electrode stack is not disposed in the folding direction.

[0016] In a strut device for tabletop folding of a secondary battery cell according to one aspect of the present disclosure, the lower strut may move upward or downward below the tabletop portion while facing the upper strut. The lower strut may hold the tabletop portion together with the upper strut, and the lower strut may include: a lower inner portion on which the electrode stack is disposed in the folding direction, and the lower inner portion is disposed to face the upper inner portion; and lower outer portions disposed to face the upper outer portions, respectively disposed at two opposite ends of the lower inner portion and extending farther than the lower inner portion in the folding direction, such that a thickness of the lower outer portion that comes into contact with the tabletop portion in the folding direction is greater than a thickness of the lower inner portion, and the electrode stack is not disposed in the folding direction.

[0017] In a strut device for tabletop folding of a secondary battery cell according to one aspect of the present disclosure, the upper strut and the lower strut can prevent pressure applied to the tabletop portion in the folding direction from being transmitted to the electrode stack.

[0018] In a strut device for tabletop folding of a secondary battery cell according to one aspect of the present disclosure, the upper outer portion and the lower outer portion can prevent the tabletop portion positioned behind the upper outer portion and the lower outer portion based on the folding direction from being deformed by pressure applied to the tabletop portion in the folding direction.

[0019] In a strut device for tabletop folding of a secondary battery cell according to one aspect of the present disclosure, the upper outer portion can protrude further downward than the upper inner portion, or the lower outer portion can protrude further upward than the lower inner portion.

[0020] In a strut device for tabletop folding of a secondary battery cell according to one aspect of the present disclosure, at least one of the upper outer portion and the lower outer portion can include a protrusion having a stepped portion formed on surfaces of the protrusion facing each other, the stepped portion can protrude while coinciding with the end line of the tabletop portion, and the upper outer portion or the lower outer portion without the stepped portion can cooperate with the stepped portion.

[0021] In a strut device for tabletop folding of a secondary battery cell according to one aspect of the present disclosure, the upper outer portion and the lower outer portion can be detachably coupled to the upper inner portion and the lower inner portion, respectively.

[0022] In a strut device for tabletop folding of a secondary battery cell according to one aspect of the present disclosure, the protrusion can be detachably coupled to the upper outer portion and the lower outer portion.

[0023] Advantageous Effects

[0024] According to the present disclosure, the upper outer portion and the lower outer portion are formed at two opposite ends of each of the upper strut and the lower strut and extend in the width direction of the secondary battery cell. Accordingly, deformation defects in which the outer tabletop cannot be supported by the electrode stack can be prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a view showing an example of a strut device for tabletop folding of a secondary battery cell.

[0026] Figure 2 and Figure 3 is Figure 1 a side view of.

[0027] Figure 4 is a side view of a secondary battery cell having a tabletop surface portion that is folded by using the Figure 1 strut device for folding the tabletop surface of the secondary battery cell.

[0028] Figure 5 is a view showing a first embodiment of a strut device for folding a tabletop surface of a secondary battery cell according to the present disclosure.

[0029] Figure 6 is for explaining Figure 5 the state in which the upper strut and the lower strut in

[0030] Figure 7 hold the tabletop surface portion while moving upward or downward. Figure 8 and Figure 6 are cross-sectional views showing time points A 6100 and B 6200 in

[0031] Figure 9 is a side view of a secondary battery cell having a tabletop surface portion that is folded by using the Figure 5 strut device for folding the tabletop surface of the secondary battery cell.

[0032] Figure 10 is a view showing a second embodiment of a strut device for folding a tabletop surface of a secondary battery cell according to the present disclosure.

[0033] Figure 11 is a view showing a third embodiment of a strut device for folding a tabletop surface of a secondary battery cell according to the present disclosure. DETAILED DESCRIPTION

[0034] Hereinafter, embodiments of a strut device for folding a tabletop surface of a secondary battery cell according to the present disclosure will be described in detail with reference to the accompanying drawings.

[0035] However, it should be noted that the inherent technical spirit of the present disclosure is not limited to the following exemplary embodiments, and those skilled in the art can easily replace or change the following exemplary embodiments based on the inherent technical spirit of the present disclosure.

[0036] In addition, the terms used herein are selected for convenience of description, and when identifying the inherent technical spirit of the present disclosure, the terms used herein should be appropriately interpreted to conform to the meaning in accordance with the technical spirit of the present disclosure, rather than being limited to the dictionary meaning.

[0037] Figure 1 is a view showing an example of a strut device for folding a tabletop surface of a secondary battery cell, Figure 2 and Figure 3 isFigure 1 Side view of Figure 4 is a side view of a secondary battery cell having a table surface portion, and the table surface portion is folded by using Figure 1 the strut device for folding the table surface of the secondary battery cell in

[0038] Refer to Figure 1 , the strut device for folding the table surface of the secondary battery cell includes the prior art upper strut P100 and the prior art lower strut P200.

[0039] Figure 1 shows a state where the upper strut P100 moves upward and the lower strut P200 moves downward.

[0040] The upper strut P100 and the lower strut P200 are disposed between the electrode stack 11 and the end of the table surface portion 12 of the secondary battery cell 10.

[0041] Figure 2 and Figure 3 shows the state 2100 where the upper strut P100 moves upward and the lower strut P200 moves downward, and the state 2200 where the upper strut P100 and the lower strut P200 clamp the table surface portion 12 while moving upward or downward.

[0042] In the state where the table surface portion 12 is clamped, the end of the table surface portion 12 is folded upward. In this case, the upper strut P100 supports the folded table surface portion 12.

[0043] Refer to Figure 1 , Figure 2 and Figure 3 , the folded table surface portion 12 may include an inner table surface 12a and an outer table surface 12b.

[0044] The electrode stack 11 is disposed on the inner table surface 12a in the direction in which the table surface portion 12 is folded.

[0045] The electrode stack 11 is not disposed on the outer table surface 12b in the direction in which the table surface portion 12 is folded. The outer table surface 12b is usually disposed at two opposite ends of the inner table surface 12a.

[0046] In Figure 1 , Figure 2 and Figure 3 the strut device for folding the table surface of the secondary battery cell shown, the cross-sectional shape of each of the upper strut P100 and the lower strut P200 remains constant with respect to the inner table surface 12a and the outer table surface 12b.

[0047] However, in the case of the inner tabletop 12a, the electrode stack 11 is disposed behind the upper support pillar P100 and the lower support pillar P200. On the contrary, in the case of the outer tabletop 12b, instead of the electrode stack 11, the outer tabletop 12b is disposed behind the upper support pillar P100 and the lower support pillar P200. Due to this difference, when the same pressure is applied to the inner tabletop 12a and the outer tabletop 12b, the risk of deformation defects of the outer tabletop 12b increases.

[0048] Referring to Figure 4 , by using the pillar device for folding the tabletop of the secondary battery cell in Figure 1 , it is possible to identify the deformation defect NG of the tabletop portion occurring on the secondary battery cell having the folded tabletop portion.

[0049] Figure 4 The deformation defect NG of the tabletop portion shown in Figure 1 occurs at the defect occurrence position 13 in

[0050] Figure 1 The defect occurrence position 13 in

[0051] is a position spaced apart from the outer tabletop 12b in the width direction of the secondary battery cell 10.

[0052] On the contrary, the electrode stack is not disposed on the outer tabletop 12b in the direction in which the tabletop portion 12 is folded. Therefore, during the process of folding the tabletop portion 12, the unfolded tabletop portion 12 is deformed.

[0053] This is because when the outer tabletop portion 12 is folded, the tabletop portion 12 at the defect occurrence position 13 is pressed in the lateral direction.

[0054] Therefore, the tabletop portion 12 at the defect occurrence position may wrinkle or bend in the up / down direction.

[0055] Figure 5 is a diagram showing a first embodiment of a pillar device for folding a tabletop of a secondary battery cell according to the present disclosure.

[0056] In addition, Figure 6 is a diagram for explaining the state in which the upper support pillar and the lower support pillar in Figure 5 hold the tabletop portion while moving upward or downward, Figure 7 and Figure 8 is a diagram showing Figure 6 the cross-sectional views at time point A and time point B in

[0057] Referring to Figures 5 to 7 andFigure 8 , the pillar device for table surface folding of the secondary battery unit according to the present embodiment is a device for supporting the table surface portion 12 to be folded in the folding direction. The secondary battery unit 10 has an electrode stack 11 and a table surface portion 12.

[0058] The electrode stack 11 is constructed by stacking electrodes and is formed thicker than the table surface portion 12.

[0059] The table surface portion 12 is formed along the outer periphery of the electrode stack 11, and a part of the table surface portion 12 is folded toward the electrode stack 11.

[0060] The pillar device for table surface folding of the secondary battery unit according to the present embodiment has an upper pillar 100 and a lower pillar 200.

[0061] The upper pillar 100 includes an upper inner portion 110 and an upper outer portion 120, and moves upward or downward at a position above the table surface portion 12 of the secondary battery unit 10.

[0062] The upper inner portion 110 is disposed between the electrode stack 11 and the end line of the table surface portion 12. The electrode stack 11 is disposed in the folding direction of the table surface portion 12.

[0063] The upper outer portion 120 is disposed at two opposite ends of the upper inner portion, and the electrode stack 11 is not disposed in the folding direction of the table surface portion 12. In addition, the upper outer portion 120 may extend farther than the upper inner portion 110 in the folding direction of the table surface portion 12.

[0064] The lower pillar 200 includes a lower inner portion 210 and a lower outer portion 220, and moves upward or downward. The lower pillar 200 is disposed below the table surface portion 12 of the secondary battery unit 10 and faces the upper pillar 100.

[0065] The lower inner portion 210 is disposed below the upper inner portion 110.

[0066] The lower outer portion 220 is disposed below the upper outer portion 120 and extends farther than the lower inner portion 210 in the folding direction of the table surface portion 12.

[0067] Specifically, in the case of the upper pillar 100 and the lower pillar 200, in the region where the electrode stack 11 is disposed at the rear side based on the folding direction (i.e., Figure 1 region 12a in), the thickness for holding the table surface portion 12 is greater than that in the region where the electrode stack 11 is not disposed at the rear side based on the folding direction (i.e., Figure 1 region 12b in) for holding the thickness of the table surface portion 12.

[0068] Therefore, since the upper exterior 120 and the lower exterior 220 according to the present disclosure extend further in the folding direction than the upper interior 110 and the lower interior 210, respectively, deformation defects of the tabletop portion 12 can be prevented from occurring at the defect occurrence positions.

[0069] Since the upper exterior 120 and the lower exterior 220 extend further in the folding direction of the tabletop portion 12, the strut device can be in close contact with and restrict a wide area of the upper and lower surfaces of the tabletop portion 12, thereby preventing the appearance of wrinkles caused by the lateral pressure applied to the tabletop portion 12 during the folding process.

[0070] Figure 9 is a side view of a secondary battery cell having a tabletop portion, which is folded by using Figure 5 the strut device for tabletop folding of the secondary battery cell in

[0071] Referring to Figure 9 , it can be seen that separation of the tabletop portion in Figure 4 and deformation defects at the defect occurrence positions can be prevented.

[0072] Figure 10 is a view showing a second embodiment of the strut device for tabletop folding of a secondary battery cell according to the present disclosure.

[0073] Referring to Figure 10 , in the strut device for tabletop folding of a secondary battery cell according to the present embodiment, the upper exterior 120 may protrude further downward than the upper interior 110, or the lower exterior 220 may protrude further upward than the lower interior 210.

[0074] Therefore, the strut device for tabletop folding of a secondary battery cell according to the present embodiment can press and clamp the upper and lower surfaces of the outer tabletop 12b.

[0075] As can be seen from Figures 5 to 7 and Figure 8 , both the upper interior 110 and the lower interior 210 have a narrow and long structure.

[0076] When the upper interior 110 and the lower interior 210 face each other and move while moving upward or downward to press the tabletop portion 12, the tabletop portion 12 is disposed in a gap defined between the upper interior 110 and the lower interior 210. This gap is larger than the thickness of the tabletop portion 12.

[0077] The upper interior 110 provides a support surface on which the tabletop portion 12 to be folded is supported. In addition, the lower interior 210 prevents the tabletop portion 12 to be folded from bending downward.

[0078] That is, the upper inner part 110 and the lower inner part 210 support the upper surface and the lower surface of the table surface part 12 without physically pressing the folded table surface part 12, making it easy to form the shape to be formed.

[0079] If the gap is smaller than the thickness of the table surface part 12, the upper inner part 110 and the lower inner part 210 physically press the table surface part 12 to be folded.

[0080] Therefore, a defect may occur in which the insulation resistance decreases between the electrode and the bag-shaped aluminum layer constituting the secondary battery cell.

[0081] However, the upper outer part 120 and the lower outer part 220 provided on the upper surface and the lower surface of the outer table surface 12b can limit the upper surface and the lower surface of the outer table surface 12b by using a large surface.

[0082] That is, the upper outer part 120 and the lower outer part 220 provided adjacent to the upper surface and the lower surface of the outer table surface 12b prevent the outer table surface 12b from wrinkling when the table surface part 12 is bent. Therefore, deformation defects can be prevented from occurring at the defect occurrence position 13.

[0083] In addition, by using a larger surface compared to the upper inner part 110 and the lower inner part 210, the upper outer part 120 and the lower outer part 220 can make surface contact with the outer table surface 12b.

[0084] Therefore, even when the upper outer part 120 and the lower outer part 220 press the table surface part 12, especially the outer table surface 12b, the above-mentioned defect of reduced insulation resistance can be prevented.

[0085] That is, the pillar device for folding the table surface of the secondary battery cell according to the present embodiment can hold the table surface part 12 while minimizing damage to the outer table surface 12b.

[0086] In addition, in the pillar device for folding the table surface of the secondary battery cell according to the present embodiment, the upper outer part 120 and the lower outer part 220 can be detachably coupled to the upper inner part 110 and the lower inner part 210, respectively.

[0087] In this case, the upper outer part 120 and the lower outer part 220 can be separated from the upper inner part 110 and the lower inner part 210 along the outer separation line 220a.

[0088] In the secondary battery cell 10, a bag having a complex multi-layer structure is used to seal the electrode and form the table surface part 12.

[0089] Therefore, when the type or structure of the bag changes, the thickness of the table surface part 12 changes.

[0090] A process of precisely modifying the upward / downward movement length needs to be performed to move the upper support column 100 and the lower support column 200 upward or downward without damaging the table top portion 12.

[0091] In the support column device for table top folding of a secondary battery cell according to the present embodiment, when the type of the bag constituting the secondary battery cell 10 is changed, it is not necessary to change the control length of the upward / downward movement length of the upper support column 100 and the lower support column 200, so the thickness of the table top portion 12 changes.

[0092] Figure 11 It is a diagram showing a third embodiment of a support column device for table top folding of a secondary battery cell according to the present disclosure.

[0093] In the support column device for table top folding of a secondary battery cell according to the present embodiment, at least one of the upper outer portion 120 and the lower outer portion 220 may further include a protrusion 221.

[0094] The protrusion 221 has a stepped portion 221b formed on the surfaces of the protrusion 221 facing each other. The stepped portion 221b protrudes while coinciding with the end line of the table top portion.

[0095] In this case, the upper outer portion 120 or the lower outer portion 220 without the stepped portion 221b cooperates with the stepped portion 221b.

[0096] In the present embodiment, the stepped portion 221b provided to coincide with the end line of the table top portion 12 restricts the table top portion 12 so that the table top portion 12 does not deform in the lateral direction.

[0097] Due to the nature of the table top portion 12, as described above, very precise control is required to apply physical external force.

[0098] However, as the control precision increases, the operation time or volume increases, and expensive precise control components are required.

[0099] The support column device for table top folding of a secondary battery cell according to the present embodiment limits the minimum value of the gap when the upper support column 100 and the lower support column 200 face each other and press the table top portion 12 while moving upward or downward.

[0100] In addition, in the support column device for table top folding of a secondary battery cell according to the present embodiment, the protrusion 221 may be detachably coupled to the upper outer portion 120 and the lower outer portion 220.

[0101] In this case, the protrusion 221 can be separated from or coupled to the upper outer portion 120 and the lower outer portion 220 along the protrusion off-line 221a.

[0102] The tabletop portion 12 of the secondary battery cell, specifically the outer tabletop 12b, can vary according to the product type of the secondary battery cell.

[0103] The strut device for folding the tabletop of the secondary battery cell according to the present embodiment can be applied to various types of secondary battery cells because the protrusion 221 is detachably coupled to the upper exterior 120 and the lower exterior 220.

Claims

1. A strut device for tabletop folding of a secondary battery cell, the strut device supporting a tabletop portion of the secondary battery cell in a direction facing the folding direction, the secondary battery cell including an electrode stack formed by stacking electrodes, and the tabletop portion being formed along an outer periphery of the electrode stack and having a portion that folds toward the electrode stack in the folding direction, the strut device including: an upper strut and a lower strut, the upper strut and the lower strut being disposed in front of the electrode stack based on the folding direction and both extending to have a length from one end to the other end of the secondary battery cell in a direction orthogonal to the folding direction, the upper strut and the lower strut being disposed above and below the tabletop portion while facing each other and being configured to hold the tabletop portion, wherein the upper strut and the lower strut are configured such that a thickness for holding the tabletop portion in a region of the electrode stack disposed on a rear side based on the folding direction is greater than a thickness for holding the tabletop portion in a region of the electrode stack not disposed on the rear side based on the folding direction.

2. The strut device according to claim 1, wherein, The upper strut moves upward or downward on the tabletop portion, and the upper strut is disposed between the electrode stack and the tabletop portion, and wherein the upper strut includes: an upper inner part, on which the electrode stack is disposed in the folding direction; and an upper outer part, the upper outer parts being respectively disposed at two opposite ends of the upper inner part and extending farther than the upper inner part in the folding direction such that a thickness of the upper outer part that comes into contact with the tabletop portion in the folding direction is greater than a thickness of the upper inner part, and the electrode stack is not disposed in the folding direction.

3. The strut device according to claim 2, wherein, The lower strut moves upward or downward under the tabletop portion while facing the upper strut, and the lower strut holds the tabletop portion together with the upper strut, and wherein the lower strut includes: a lower inner part, on which the electrode stack is disposed in the folding direction, the lower inner part being disposed to face the upper inner part; and a lower outer part, the lower outer part being disposed to face the upper outer part, respectively disposed at two opposite ends of the lower inner part and extending farther than the lower inner part in the folding direction such that a thickness of the lower outer part that comes into contact with the tabletop portion in the folding direction is greater than a thickness of the lower inner part, and the electrode stack is not disposed in the folding direction.

4. The strut device according to claim 3, wherein, The upper strut and the lower strut prevent pressure applied to the tabletop portion in the folding direction from being transmitted to the electrode stack.

5. The strut device according to claim 3, wherein, The upper outer part and the lower outer part prevent the tabletop portion positioned behind the upper outer part and the lower outer part based on the folding direction from being deformed by pressure applied to the tabletop portion in the folding direction.

6. The strut device according to claim 3, wherein, The upper outer part protrudes farther downward than the upper inner part, or the lower outer part protrudes farther upward than the lower inner part.

7. The strut device according to claim 3, wherein, At least one of the upper exterior and the lower exterior includes a protrusion having a stepped portion formed on surfaces of the protrusion facing each other, the stepped portion protruding while coinciding with an end line of the stepped surface portion, and wherein the upper exterior or the lower exterior that does not have the stepped portion cooperates with the stepped portion.

8. The strut device according to claim 3, wherein, The upper exterior and the lower exterior are respectively detachably coupled to the upper interior and the lower interior.

9. The strut device according to claim 7, wherein, The protrusion is detachably coupled to the upper exterior and the lower exterior.

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