JP4951876B2 - Manufacturing method of prismatic non-aqueous electrolyte battery - Google Patents

Description

  The present invention relates to a method for manufacturing a prismatic nonaqueous electrolyte battery, and more particularly to a core shape when a positive electrode plate and a negative electrode plate are wound through a separator to constitute an electrode plate group.

  In conventional rectangular nonaqueous electrolyte batteries, the winding core shape for winding was close to that of a flat plate. However, the fluctuation in angular velocity during winding was large, and the fluctuation in electrode plate tension was large. Because the winding speed could not be increased, productivity was reduced.

For this reason, various types of cores have been proposed. For example, when winding the electrode plate group, a rhombus core or a core having a substantially hexagonal core shape and a groove passing through the center of two opposite sides of the substantially hexagonal shape has been used. (See Patent Document 1 or Patent Document 2)
JP 2002-75429 A JP 2001-202986 A

  However, the conventional winding core has problems such as an increase in the amount of separator on the inner periphery or a large space at the center, and problems such as variations in the position of current collecting leads. .

  In order to solve these conventional problems, the method for manufacturing a rectangular nonaqueous electrolyte battery according to the present invention is such that the shape of the core used is one set of parallel long sides and two sets of parallel short sides. The longest diagonal line that is the longest diagonal line connecting the vertices of the approximate hexagon when the core shape is approximated to a hexagonal shape, and the length Sides are parallel, the core groove is disposed between the longest diagonal line and the adjacent diagonal line adjacent to the longest diagonal line, and the core parts divided by the core groove are non-axisymmetric and point symmetric It is characterized by being.

  The substantially hexagonal shape of the present invention includes a shape in which the apex of the approximate hexagon is rounded or chamfered. In addition, the winding core groove is a winding formed when the first winding core and the second winding core are combined as long as the winding core is configured by a combination of the first winding core and the second winding core. It is a gap between cores, and if it is a core composed of a single core, it is a groove disposed on the core.

  By using the point-symmetrical winding core of the present invention, the amount of separator used at the time of winding can be shortened, and the winding speed can be increased by approaching the circular shape of the winding group. Can be improved.

  Further, in the approximate hexagon of the core, the ratio A / B of the length A of the longest diagonal line and the length B of the perpendicular line extending from the longest diagonal line to the long side is 1.5 or more and 2.5 or less. Preferably, the core groove has a linear shape, and an angle formed by the core groove and the longest diagonal is preferably 5 ° to 30 °. With such a configuration, the effect of the present invention is remarkably exhibited.

  According to the present invention, in the winding of the electrode plate group, not only can the winding speed be increased, but also the amount of the inner separator can be reduced and the variation in the position of the current collecting leads can be reduced. A method for producing a nonaqueous electrolyte battery can be provided.

  The gist of the present invention is that the shape of the core when forming the electrode plate group is a substantially hexagonal shape with a long pair of sides, and the core portions divided by the core groove are non-axisymmetric. By using a pair of winding cores that are point-symmetric, it is possible to suppress variations in the position of the current collecting leads and to suppress slippage of the separator during winding, so the amount of separator used during winding Since the winding speed can be increased when the shape of the winding group approaches a circle, the productivity can be improved.

  FIG. 1 (a) shows a core according to the present invention, FIG. 1 (b) shows the core insertion state before winding, and FIG. 1 (c) shows a state diagram in which the core is rotated about 120 ° and the negative electrode is inserted. ), A state where the winding core is rotated by 180 ° is shown in FIG. 1D, and a state where the winding core is initially wound around is shown in FIG.

  In FIG. 1 (a), the shape of the core is a substantially hexagonal shape with three sets of parallel straight lines consisting of one set of parallel long sides 11 and two sets of parallel short sides 12 as sides. Further, the longest diagonal line 1 that is the longest diagonal line connecting the apexes of the approximate hexagon when the core shape is approximated to a hexagon is parallel to the long side 11. The core groove 3 is disposed between the longest diagonal line 1 and the adjacent diagonal line 13 adjacent thereto, and the core parts 2 divided by the core groove 3 are non-linearly symmetric and point-symmetric.

  When the core groove 3 is arranged between the longest diagonal line 1 and the adjacent diagonal line 13 adjacent to the longest diagonal line 1 as shown in FIG. 1 (a), the state where the core is inserted is as shown in FIG. 1 (b). Become. When this is wound, the separator 5 is disposed below the core by applying tension by sandwiching it with the separation nip roller 7 from the lower side of the core and balancing the tension in the vertical direction. And rub the separator 5 from above the core.

  Then, when the core is rotated by 120 °, the negative electrode plate 8 is plunged as shown in FIG. Then, since the negative electrode tension is applied, the upward tension increases.

  However, at this time, since the separator 5 is sandwiched between the separation nip rollers 7, the tension balance is maintained.

  Then, when the winding core is rotated 180 °, as shown in FIG. 1D, the tip of the separator 5 under the winding core reaches the vicinity of the separation nip roller.

  When the separator is further rotated and the separator tip is detached from the separation nip roller, the downward tension disappears. At this time, if the upper and lower tension balance is lost, the winding from the upper direction stops, and the winding core idles.

  As a result, the position of the negative electrode plate 8 is displaced, and the position of the current collecting lead 7 varies.

  However, since the separator 5 positioned at the apex 6 of the core groove 3 is in contact with the negative electrode plate 8 disposed immediately above, a downward tension is generated, so that the negative electrode plate 8 can be wound. . The amount of separator used during initial winding varies depending on the number of rotations until the negative electrode plate 8 is inserted.

  Conventional winding cores require a rotational speed of 270 ° or more before entering the negative electrode. However, by using the core of the present invention, the separator 5 positioned at the apex 6 of the core groove 3 can contact the negative electrode plate 8 disposed on one sheet with a small number of rotations, so that the initial winding can be performed. The amount of separator used can be reduced.

  Further, since the core groove 3 can be tilted with respect to the longest diagonal line 1 by making the core shape non-symmetrical, the negative electrode plate on which the separator located at the apex 6 of the core groove 3 is disposed. The rotation angle required until it contacts 8 can be reduced.

  Also, by making the core non-symmetrical, the core groove 3 can be made parallel to the longest diagonal line 1, and the inner peripheral electrode plate after the core is removed as shown in FIG. 1 (f). The slack can be stopped by the separator 5.

  Further, since the pressure shaping direction 10 for the winding group and the core groove 3 are close to being perpendicular, it is possible to suppress variations in the position of the negative electrode current collecting lead 9.

  Further, since the center of rotation can be provided on the winding core groove 3 by using point symmetry, the eccentricity at the time of winding is eliminated, the fluctuation of angular velocity can be reduced, and the winding speed can be reduced. Can increase productivity.

  Further, in the approximate hexagon, when the ratio A / B of the length A of the longest diagonal line 1 and the length B of the perpendicular line dropped to the long side 11 is 2.5 or less, the core shape becomes closer to a circle. Therefore, since the fluctuation of the angular velocity of the winding core during winding is reduced, it is preferable in that the winding speed can be further increased and productivity can be improved.

  Here, if it is larger than 2.5, the fluctuation of the angular velocity at the time of winding increases, and the winding speed must be lowered, which is not preferable.

  If it is smaller than 1.5, the space in the group pressure shaping direction of FIG. 1 (e) increases, and the space where the inner electrode plate sags increases. It is not preferable because the position of the lead 9 varies.

  Moreover, the core groove | channel 3 is a linear shape, and when the angle | corner 4 which the core groove | channel 3 and the longest diagonal line 1 make is 5 degrees-30 degrees, the separator arrange | positioned at the core groove | channel 3 is a winding group. Since it is parallel to the long side direction, the number of overlapping inner circumferential separators can be reduced, which is preferable.

  When the angle is less than 5 °, it is difficult to remove the core, which requires a complicated mechanism for removing the core. The rotation angle required to contact the negative electrode plate 8 is increased, so that the amount of inner circumferential separator used is increased, and the separator disposed in the core groove 3 is perpendicular to the long side direction of the winding group. Therefore, when the pressure shaping is performed, the separator disposed in the core groove 3 is bent in an S shape, which is not preferable because the number of overlapping inner peripheral separators increases.

  In this example, KAW-4BTQH-M manufactured by Minato Seisakusho was used as the winding machine.

  As shown in FIG. 4, the core is formed of a first core portion 2 and a second core portion 2 using a substantially hexagonal core in which each apex of the approximate hexagon is chamfered. The core groove 3 is constituted by a gap when the one core portion 2 and the second core portion 2 are combined.

The angle 4 formed by the longest diagonal line 1 and the core groove 3 is 12 °.
This core is referred to as the core 1. In the core 1, the first core portion 2 and the second core portion 2 are not line-symmetric when combined, that is, non-linearly symmetric and point-symmetric.

  Further, the ratio A / B between the length A of the longest diagonal line 1 and the length B of the perpendicular line extending from the longest diagonal line 1 to the long side 11 is 2.5.

  As a comparative example, a core 2 using a conventionally known flat core shown in FIG.

Furthermore, as shown in FIG. 2A, a substantially hexagonal core similar to the core 1 is used, but the angle formed by the longest diagonal line and the core groove is vertical (90 °). Is the core 3.
Unlike the core 1, the core 3 is point-symmetric but line-symmetric.

Table 1 shows the production tact and the amount of use of the inner separator when the cores 1 to 3 are wound with the above-described winding machine, and 30 lead positions are measured for each, and the variation is shown. Is also shown in Table 1.

  From Table 1, by using the core of the present invention, the production tact increased, and the amount of separator used on the inner periphery could be shortened. Furthermore, it was confirmed that the current collecting lead position was stable.

  The reason for this is that, in a flat core like the core 2, the lead position is stable, but the fluctuation of the angular velocity during winding is large, the fluctuation of the electrode plate tension is large, and the winding speed cannot be increased. , Production tact is reduced.

  Further, when a vertical core such as the core 3 is used, as can be understood by comparing FIG. 2B and FIG. This is because the rotation angle required to contact the negative electrode plate 8 disposed above increases, so that the amount of inner peripheral separator used increases, and the electrode plate group using many separators is wound.

  In the core 3, as shown in FIG. 2C, the inner separator sag in a direction parallel to the pressurizing direction, so that the electrode plate collapses inward and pressurizes in a collapsed state. Variations occur.

  However, since the separator 1 exists in parallel with the longest diagonal line in the core 1 of the present invention, it is possible to suppress the slack of the electrode plate due to the slack of the inner periphery. The electric lead position is stable.

  Also in this example, KAW-4BTQH-M manufactured by Minato Seisakusho was used as the winding machine.

Cores 4 to 7 having substantially the same hexagonal shape as the core 1 of Example 1 but having A / B changed as shown in FIGS. 5 to 8 were prepared.
Here, the angles 4 formed by the longest diagonal line 1 and the core groove 3 are all 12 °.

Accordingly, Table 2 shows the aspect ratio and production tact of the core when the cores 4 to 7 are wound with the above-described winding machine, and variations in the current collecting lead position.

  From Table 2, it is more preferable to set A / B to 1.5 or more and 2.5 or less because productivity can be further improved and variation in the lead position for current collection after group pressure shaping can be suppressed.

  The reason for this is that when the A / B is 2.5 or less, the core shape is closer to a circle, so that the fluctuation of the angular velocity during winding is reduced, and the winding speed can be increased. This can be further improved, and if 1.5 or more, variations in the current collecting lead position after group pressure shaping are suppressed.

  Also in this example, KAW-4BTQH-M manufactured by Minato Seisakusho was used as the winding machine. Although substantially the same hexagonal shape as the core 1 of Example 1, as shown in FIG. 9, cores 8 to 16 were produced in which the angle 4 formed by the longest diagonal line 1 and the core groove 3 was changed.

  Here, the ratios A / B of the length A of the longest diagonal line 1 and the length B of the perpendicular line extending from the longest diagonal line 1 to the long side 11 are all 2.5.

  By changing the angle 4 formed by the winding core groove 3 and the longest diagonal line 1 of the present invention, the length of the inner circumferential separator, or the number of overlapping inner circumferential separators depending on how the separators are folded during pressurization, and further the winding The detachability of the lead changes.

  An increase in the number of overlapping inner peripheral separators increases the thickness of the group, and the detachability of the core affects the increase in process defects.

  Therefore, Table 3 shows the results of the inner separator length, the number of overlapping inner peripheral separators, and the removal property of the core when the above-described cores 8 to 16 are wound with the aforementioned winding machine.

  As shown in Table 3, the length of the inner peripheral separator can be shortened, the core pull-out property can be secured, and the number of overlapping inner peripheral separators can be suppressed. It is more preferable that the angle formed by is 5 ° to 30 °.

  The prismatic nonaqueous electrolyte battery manufactured by the method for manufacturing a highly productive prismatic nonaqueous electrolyte battery of the present invention is useful as a power source for inexpensive portable equipment for consumer use.

(A) Schematic diagram of the core of one embodiment of the present invention, (b) An explanatory diagram of the core inserted state before winding, (c) The state where the core is rotated 120 ° and the negative electrode is inserted. Explanatory drawing, (d) Explanatory drawing of the state in which the core is rotated by 1180 °, (e) Explanatory drawing when the separator is wound around the winding core, (f) Explanatory drawing when the winding core is removed (A) Schematic diagram of a conventional core, (b) an explanatory diagram when the separator is wound around the core, (c) an explanatory diagram when the core is removed Schematic diagram of conventional second core The schematic diagram of the 1st core used in the Example of this invention Schematic diagram of the second core used in the example of the present invention The schematic diagram of the 3rd core used in the Example of this invention The schematic diagram of the 4th core used in the Example of this invention Schematic diagram of the fifth core used in the example of the present invention Schematic diagram of the sixth core used in the example of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Longest diagonal line 2 Winding core part 3 Winding core groove 4 Corner 5 Separator 6 Apex 7 Sepa nip roller 8 Negative electrode plate 9 Negative electrode current collection lead 10 Pressure shaping direction 11 Long side 12 Short side 13 Adjacent diagonal line

Claims (2)

A method for manufacturing a rectangular nonaqueous electrolyte battery in which a positive electrode plate and a negative electrode plate are wound using a core having a core groove through a separator, and an electrode plate group and an electrolyte solution are accommodated in a case. In
The shape of the core is a substantially hexagonal shape with three sets of parallel straight lines consisting of a pair of parallel long sides and two sets of parallel short sides as sides, and the core shape is a hexagonal shape. The longest diagonal line that connects the vertices of the approximate hexagon when approximated is the longest diagonal line and the long side are parallel, and the core groove is disposed between the longest diagonal line and the adjacent diagonal line adjacent thereto. The core parts divided by the core groove are non-linearly symmetric and point-symmetric, and the method of manufacturing a rectangular nonaqueous electrolyte battery is characterized in that the approximate hexagonal shape is: A ratio A / B of the length A of the longest diagonal line and the length B of a perpendicular line extending from the longest diagonal line to the long side is 1.5 or more and 2.5 or less. Manufacturing method of electrolyte battery . A method for manufacturing a rectangular nonaqueous electrolyte battery in which a positive electrode plate and a negative electrode plate are wound using a core having a core groove through a separator, and an electrode plate group and an electrolyte solution are accommodated in a case. In
The shape of the core is a substantially hexagonal shape with three sets of parallel straight lines consisting of a pair of parallel long sides and two sets of parallel short sides as sides, and the core shape is a hexagonal shape. The longest diagonal line that connects the vertices of the approximate hexagon when approximated is the longest diagonal line and the long side are parallel, and the core groove is disposed between the longest diagonal line and the adjacent diagonal line adjacent thereto. The core portions divided by the core groove are non- linearly symmetric and point-symmetric, and the method of manufacturing a rectangular nonaqueous electrolyte battery is characterized in that the core groove is a straight line. the shape, the angle between the longest diagonal line and the winding core grooves, prismatic non-aqueous electrolyte preparation of cells, which is a 5 ° to 30 °.