JP4978530B2 - Cylindrical battery and manufacturing method thereof - Google Patents

Description

  The present invention relates to an improvement in a separator interposed between a positive electrode material and a negative electrode material of a cylindrical battery typified by a dry battery.

  In recent years, many electronic devices that discharge large currents, such as portable information devices and digital cameras that require high-load discharge performance, have spread in the market. As power sources for these electronic devices, demand for cylindrical batteries typified by alkaline manganese batteries and oxyride batteries is rapidly increasing. Accordingly, there is a demand for, for example, improving production efficiency of alkaline manganese dry batteries and producing high-quality, reliable, large-capacity, high-power cylindrical batteries.

  FIG. 7 shows the configuration of an alkaline manganese dry battery according to the prior art. An alkaline manganese battery has a cylindrical positive electrode material 104, a cylindrical cylindrical separator 101 and a square bottom separator 102, a gel negative electrode in a battery case 103 having a positive electrode convex portion 85 formed at the bottom of a cylindrical outer shape. The material 106 is accommodated, and the opening end of the battery case 103 is sealed with the sealing plate 88 through the insulating gasket 87, and the negative electrode current collecting rod 89 inserted into the gelled negative electrode material 106 is connected to the sealing plate 88. Has been. A bottom separator 102 is provided at the bottom of the battery case 103, and a method of isolating the gel-like negative electrode material 106 and the battery case 103 serving as a positive electrode terminal so as not to be internally short-circuited has been proposed (for example, Patent Document 1).

  Moreover, the state diagram which shows the process sequence of the manufacturing apparatus which concerns on the structure of the conventional alkaline manganese dry battery is shown to Fig.8 (a)-(c). As shown in FIG. 8A, the battery case 103 into which the positive electrode material 104 has been inserted in the previous process is housed in the battery transport jig 110, and a circular guide hole 114 through which the cylindrical separator 101 can pass and the guide hole 114. The battery carrying jig 110 is arranged so that the center of the separator loading jig 112 including the holding part 111 that holds the square bottom separator 102 on the upper side, the center of the battery case 103, and the center of the cylindrical separator 101 are on the same axis. And the separator loading jig 112 are conveyed.

  Next, as shown in FIG. 8B, the cylindrical separator 101 and the separator loading jig 112 wound around the winding core 113 in a cylindrical shape so as to be in contact with the inner peripheral surface of the positive electrode material 104 in the battery case 103. The bottom separator 102 held by the holding portion 111 is inserted into the battery case 103 by causing the core 113 to abut the tip of the cylindrical separator 101 against the bottom separator 102 and simultaneously passing both separators through the guide holes 114.

Thereafter, as shown in FIG. 8C, the core 113 is raised while the separators 101 and 102 inserted in the battery case 103 are disposed, and the battery transport jig 110 is moved to the next step (not shown). It is conveyed to. Thereafter, in the next step, a negative electrode gelling agent is introduced into the central space surrounded by the separators 101 and 102, and after pouring the electrolyte, the opening of the battery case 103 is sealed with a sealing plate to produce a cylindrical battery. Has been proposed (see, for example, Patent Document 2).
Japanese Patent No. 3555211 Japanese Patent No. 3655469

  However, in the prior art disclosed in the above-mentioned patent document, as shown in FIG. 9, the corner portion 102a of the bottom separator 102 overlaps the overlapping portion 101a consisting of the start and end of winding of the cylindrical separator 101, and the negative electrode material 106 and the positive electrode The distance between the electrode 104 and the electrode 104 is partially increased to cause a shortage of reaction between the two electrodes, and the capacity of the negative electrode material 106 is decreased, so that the required discharge performance cannot be obtained.

  That is, as shown in the perspective view of the assembled state of the cylindrical separator 101 and the bottom separator 102 shown in FIG. The overlapping surface 101 a where the winding ends overlap and the bent corner portion 102 a of the bottom separator 102 overlap and become thick, and the negative electrode material 106 and the positive electrode material 104 shown in FIG. 7 face each other through the cylindrical separator 101. The distance between the electrodes is partially increased to form a gap, and the reaction between the negative electrode material 106 and the positive electrode material 104 is deteriorated. In addition, since the separators are overlapped by the overlapping portion 101a of the cylindrical separator 101 and the corner portion 102a of the bottom separator 102, the capacity of the negative electrode material 106 is reduced, and the required discharge performance cannot be obtained. There was a problem.

  The present invention has been made in view of the above-described conventional problems. Since the bottom separator has a partial cut portion, the bottom separator cannot be complicatedly wrinkled, and the position of the folded portion can be determined in advance. In addition, it is possible to suppress the decrease in capacity of the negative electrode material due to complicated folding, and the distance between the positive electrode material and the negative electrode material through both separators is uniform, so that variation in internal resistance can be suppressed and discharge An object of the present invention is to provide a highly reliable, large capacity, high power cylindrical battery capable of suppressing variation in characteristics and improving discharge characteristics.

  In order to achieve the above object, a cylindrical battery according to the present invention includes a positive electrode material, a negative electrode material, a cylindrical separator interposed between the positive electrode material and the negative electrode material, and a bottom separator that wraps the end of the cylindrical separator. In a cylindrical battery housed in a battery case having a shape, the bottom separator has a partially cut portion that prevents bending wrinkles that occur when it is bent along the cylindrical shape of the cylindrical separator, and the cylindrical separator is It is characterized by being configured to wrap.

  According to the present invention, the bottom separator is bent by wrapping the tubular separator from the outside with the bottom separator having a partially cut portion that prevents bending wrinkles generated by bending along the cylindrical shape of the tubular separator. In addition, it is possible to suppress a decrease in capacity of the negative electrode material due to complex wrinkles that can be generated, and the distance between the positive electrode material and the negative electrode material becomes uniform, suppressing variations in internal resistance, improving discharge characteristics, and providing high capacity and high reliability. It becomes possible to obtain sex.

  A first aspect of the present invention is a battery case having a cylindrical shape including a positive electrode material, a negative electrode material, a cylindrical separator interposed between the positive electrode material and the negative electrode material, and a bottom separator that wraps an end of the cylindrical separator. In the cylindrical battery housed inside, the bottom separator has a partial cutout portion that prevents bending wrinkles that occur when the cylindrical separator is bent along the cylindrical shape of the cylindrical separator, and is configured to wrap the cylindrical separator from the outside. As a result, when the cylindrical separator and the bottom separator are mounted, complicated folding due to the bending of the bottom separator cannot be performed, so that a decrease in the capacity of the negative electrode material is suppressed, and the discharge characteristics can be improved.

  According to a second aspect of the present invention, in the first aspect, by making the shape of the bottom separator square, it is possible to determine the position of the overlapping portion that can be formed into the bottom separator when mounted in the battery case. The yield efficiency of raw materials can be improved.

  According to a third aspect of the present invention, in the first aspect, since the partially cut portions have at least two positions opposite to each other, complicated wrinkles are not generated in the bottom separator when mounted in the battery case. Since the position of the folded portion can be determined, the distance between the positive electrode material and the negative electrode material becomes uniform, and the discharge characteristics can be improved.

  According to a fourth aspect of the present invention, in the first aspect of the invention, the bottom separator is bent in a plurality of bent portions because the cylindrical separator formed by winding the partially cut portion and the cylindrical shape does not overlap each other. Since the folded overlap portion and the winding end of the cylindrical separator do not overlap, the distance between the positive electrode material and the negative electrode material becomes uniform, variation in internal resistance is suppressed, and discharge characteristics can be improved.

  According to a fifth aspect of the present invention, in the first aspect, a bottom separator that is folded so as to be wrapped along a cylindrical shape of the cylindrical separator and a portion formed by overlapping the winding end position and the winding start position of the cylindrical separator. Since the folded portion of the partially cut portion is configured not to overlap, the folded portion provided in the partially cut portion of the bottom separator and the overlap portion where the winding end position and the winding start position of the cylindrical separator overlap each other are formed. Since the thickness due to the overlap between both separators can be suppressed without overlapping, the distance between the positive electrode material and the negative electrode material becomes close, and the discharge characteristics can be improved.

  According to a sixth aspect of the present invention, in the first aspect, the total thickness of the overlapping portions of the cylindrical separator is minimized by making the winding start position and the winding end position of the cylindrical separator the same position. Therefore, the capacity reduction of the negative electrode material can be suppressed.

  According to a seventh aspect of the present invention, in the first aspect, the partial cut portion is disposed so as to be located outside the outer diameter of the cylindrical separator when the bottom separator and the cylindrical separator are overlapped. Occasionally, the negative electrode material does not flow out of the partially cut portion of the bottom separator, so that it is possible to improve reliability without causing leakage or internal short circuit.

  According to an eighth aspect of the present invention, in the first aspect, since the shape of the partially cut portion is V-shaped, it is possible to suppress the occurrence of complicated bending wrinkles.

  According to a ninth aspect of the present invention, in the first aspect, since the shape of the partially cut portion is a letter shape, it is possible to minimize the overlapping area of the folded portion provided in the partially cut portion. It becomes.

  According to a tenth aspect of the present invention, in the eighth to ninth aspects, by providing an R shape at the apex of the partially cut portion, it is possible to suppress the occurrence of burrs when forming the partially cut portion.

  According to an eleventh aspect of the present invention, in the first aspect, by making the shape of the partially cut portion U-shaped, it is possible to suppress overlapping wrinkles of the folded portion provided in the partially cut portion.

  According to a twelfth aspect of the present invention, in the second aspect, by providing a partially cut portion in the middle portion of the side of the bottom separator, a position where a folding portion that can be formed into the bottom separator when mounted in the battery case is determined. It is possible to suppress the occurrence of complicated folding wrinkles.

  In a thirteenth aspect of the present invention, in the fourth aspect, by arranging the partially cut portion so as to sandwich the winding end position of the cylindrical separator, it is possible to determine a place where the folded portion is generated. .

  According to a fourteenth aspect of the present invention, in the first aspect, a positive electrode mixture made of manganese dioxide and formed into a hollow cylindrical shape is used as the positive electrode material, so that a gel is formed at the center of the hollow cylindrical positive electrode mixture. The negative electrode material can be put in, and since it is compression-molded into a hollow cylindrical shape, a gel-like negative electrode material can be quantified, so that predetermined discharge characteristics can be obtained.

  According to a fifteenth aspect of the present invention, in the first aspect, by using a microporous film that transmits ions as the bottom separator, the rising portion of the bottom separator is between the positive electrode mixture pellet and the gelled negative electrode. Even if it is interposed, the reaction is not hindered, so that it is possible to obtain a certain discharge characteristic.

  According to a sixteenth aspect of the present invention, in the first aspect, as the bottom separator, the bottom separator has a rectangular shape larger than the outer diameter of the cylindrical separator, so that one end of the cylindrical separator can be completely wrapped. Therefore, it is possible to improve reliability without causing leakage or internal short circuit.

  In the seventeenth aspect of the present invention, in the first aspect, by using a microporous film that transmits ions as the cylindrical separator, handling can be simplified by using the same member as the bottom separator. The production capacity can be improved.

  In an eighteenth aspect of the present invention, a first step of storing a cylindrically formed positive electrode material in a bottomed cylindrical battery case, and a second step of inserting a bottom separator and a cylindrical tubular separator. And a third step of inserting the electrolytic solution and the gelled negative electrode material, and a fourth step of mounting the sealing body having the negative electrode current collector rod on the opening of the battery case and caulking and sealing the opening of the battery case. A cylindrical battery manufacturing method, in the second step, after forming a partially cut portion in the bottom separator, by simultaneously inserting the bottom separator and the cylindrical separator so as to wrap the cylindrical separator from the outside with the bottom separator, By providing a fold-over part formed by the partial cut-out part of the bottom separator when mounted in the battery case, the capacity of the negative electrode material is reduced without the occurrence of complicated folding wrinkles. Is suppressed, and, inter-electrode distance between the cathode material and the anode material is suppressed near becomes the internal resistance variation, the creation of cylindrical battery capable of improving the discharge characteristic becomes easy.

  According to a nineteenth aspect of the present invention, in the eighteenth aspect, a strip separator is wound in the second step to form a cylindrical tubular separator, and the winding end position of the tubular separator and a partial cut of the bottom separator are cut. By positioning the bottom separator and the cylindrical separator at the same time so as to wrap the cylindrical separator from the outside with the bottom separator, the overlapping portion of the cylindrical separator and the partial cut portion of the bottom separator Therefore, the separator can be inserted more efficiently, the negative electrode material can be stored efficiently, and productivity and cost can be improved.

  According to a twentieth aspect of the present invention, in the eighteenth aspect, as the bottom separator, a strip-shaped separator is cut into a square shape so that the lengths of the four sides have the same dimension, and a part of the middle part of the sides of the bottom separator is obtained. By cutting the part and forming the partially cut part, it is possible to minimize the cutting loss of the bottom separator and improve the yield of raw materials.

  Hereinafter, the configuration of an alkaline manganese dry battery which is an embodiment of the cylindrical battery of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, a positive electrode convex portion 6 is formed on the bottom surface so as to project outward as a positive electrode terminal, and the positive electrode terminal integrated battery case 1 formed in a bottomed cylindrical shape is connected to the inside of the battery case 1. A positive electrode material 2 molded into a hollow cylindrical shape so as to be in contact with the peripheral surface is accommodated, and an electrolyte solution (not shown) and a gel shape separated by a bottom separator 5 and a cylindrical separator 3 in the hollow of the positive electrode material 2 The negative electrode material 4 is accommodated.

  The open end of the battery case 1 is sealed by a sealing plate 8 through an insulating gasket 7 and is connected to a negative electrode current collector rod 9 inserted in a gel-like negative electrode material 4 to which a sealing plate 8 serving as a negative electrode terminal is attached. The alkaline manganese dry battery 10 is configured.

  For example, as shown in FIG. 2A, the tubular separator 3 having no bottom and no seam is disposed on the bottom separator 5 having a rectangular shape larger than the outer diameter of the tubular separator 3. Further, a V-shaped partial cut portion 5 c is provided in the middle of the side of the bottom separator 5, and the partial cut portion 5 c is located outside the outer diameter of the cylindrical separator 3. Note that the outer shape of the bottom separator 5 may be a circle, or a triangle or a polygon.

  Next, as shown in FIG. 2 (b), the lower portion of the cylindrical separator 3 is bent at the periphery of the bottom separator 5 having the corners 5a and the partially cut portions 5c, and the folded portion 5e formed by the partially cut portions 5c. In the battery case 1 shown in FIG. 1, the gelled negative electrode material 4 and the bottom surface of the battery case 1 are isolated and insulated so as not to be internally short-circuited. 2 (c), the partial cutout 5c of the bottom separator 5 may be U-shaped, or the partial cutout 5c may be Le-shaped as shown in FIG. 2 (d). A shape provided with an R shape 5f at the apex of the partially cut portion 5c as shown in FIG.

  Also, as shown in FIG. 3A, a cylindrical bottom separator 5 having a cylindrical separator 3 that is larger than the outer diameter of the cylindrical separator 3 is formed by using a cylindrical tubular separator 3 that is formed by winding a plurality of times. The position which arrange | positions above, and as shown in the top view of FIG.3 (b), the overlapping part 12 which consists of the winding start position 3b and the winding end position 3c of the cylindrical separator 3, and the partial cutting part 5c which the bottom part separator 5 does not overlap As shown in FIG. 3C, the lower part of the cylindrical separator 3 is wrapped with a rising part 5b obtained by bending the periphery of the bottom separator 5, so that the negative electrode material 4 and the bottom surface of the battery case 1 are not internally short-circuited. Isolation and insulation may be used.

  Further, as shown in FIG. 3 (c), the folded overlap portion 5e formed by the partial cutout portion 5c of the bottom separator 5 does not overlap the overlap portion 12 composed of the winding start position 3b and the winding end position 3c of the cylindrical separator 3. By mounting in the state, the overlapping portion 12 and the folded portion 5e of the bottom separator 5 do not overlap, and the problem that the capacity of the negative electrode material 4 decreases can be suppressed. It becomes uniform when the distance between the positive electrode material 2 and the negative electrode material 4 is short, and variation in the internal resistance of the battery can be suppressed.

  Also, as shown in FIG. 4, the bottom separator 5 has the cylindrical separator 3 formed by winding a plurality of times so that the winding start position 3b and the winding end position 3c of the cylindrical separator 3 are the same position. Since the partially cut portion 5c does not overlap the winding start position 3b and the winding end position 3c of the cylindrical separator 3, the gelled negative electrode material 4 does not leak from the partially cut portion 5c to the positive electrode material 2 side, so that a short circuit occurs. Can also prevent.

  As shown in FIG. 4, the partial cut portion 5 c of the bottom separator 5 is in the middle portion 5 d of the side of the bottom separator 5, and the outer side of the cylindrical separator 3 when the bottom separator 5 and the cylindrical separator 3 are overlapped with each other. It arrange | positions so that the partial cut part 5c may not enter inside diameter, and arrange | positions it so that the winding start position 3b and the winding end position 3c of the cylindrical separator 3 may be pinched | interposed, and at least 2 in the position where a partial cut part mutually opposes It may be more than the number of places.

  Hereinafter, the cylindrical battery according to the embodiment of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to this, and the present invention can be applied to a manganese battery, an oxyride battery, an air zinc battery, and the like. It doesn't matter.

  First, as shown in FIG. 1, a bottom surface of a battery case 1 formed in a bottomed cylindrical shape is provided with a positive electrode protrusion 6 formed to protrude outward to be a positive electrode terminal. The positive electrode material 2 obtained by compression-molding the positive electrode mixture into a cylindrical shape is inserted and stored in contact with the inner peripheral surface of the battery case 1. A plurality of positive electrode materials 2 formed in a cylindrical shape to be stored depending on the type of cylindrical battery are stored. In one embodiment of the present invention, two positive electrode materials 2 are stored in the battery case 1.

  The positive electrode material 2 was prepared by mixing a mixture of manganese dioxide and graphite in a weight ratio of 90:10 and an alkaline electrolyte in a weight ratio of 100: 3, sufficiently stirring, and then compression-molding into a flake shape. . Furthermore, 40% by weight sodium hydroxide aqueous solution is used as the alkaline electrolyte, and the flaky positive electrode mixture is pulverized and powdered and classified by sieving. Thus, a pellet-shaped positive electrode material 2 was obtained. Two of the positive electrode materials 2 were inserted into the battery case 1.

  Next, a strip-shaped separator having a width larger than the diameter of the cylindrical separator 3 was cut into a dimension having the same length as that of the width, and at the same time, a partially cut portion 5c was formed to form the bottom separator 5. The bottom separator 5 may be cut into a square shape from the strip-shaped separator, and then the partially cut portion 5c may be formed.

  Next, the rectangular bottom separator 5 is disposed at a position where the center of the battery case 1 and the center of the bottom separator 5 are the same. Here, the corner 5a of the bottom separator 5 cut into a square shape is positioned at the time of cutting, and is placed on the battery case 1 while maintaining the positioned state. The bottom separator 5 is made of regenerated cellulose as a microporous film that transmits only ions, and a nonwoven fabric made of chemical fibers is laminated on both sides thereof, and the thickness is preferably 0.02 to 0.3 mm.

  In addition, a strip-shaped separator having a width that is the same as the dimension in the height direction of the cylindrical separator 3 is cut into a predetermined length, and is wound into a cylindrical shape using a winding core to produce the cylindrical separator 3. Here, the number of windings of the cylindrical separator 3 is determined by the type of cylindrical battery, and in the embodiment of the present invention, the cylindrical separator 3 having three windings is used.

  Further, as shown in FIG. 3 (a), the length to be cut was cut to a length at which the winding end position 3c finished winding at the same position as the winding start position 3b by winding three times. In addition, you may cut | disconnect after winding required number of times. In addition, the cylindrical separator 3 uses the regenerated cellulose as a microporous film which permeate | transmits only an ion like the bottom part separator 5, and laminates the nonwoven fabric which consists of a chemical fiber on both surfaces.

  Next, it arrange | positions in the position where the center of the cylindrical separator 3 and the center of the battery case 1 and the bottom part separator 5 become the same. Here, the center of the cylindrical separator 3 and the center of the bottom separator 5 are matched, and the bottom separator is located at a position where the winding start position 3b, the winding end position 3c of the cylindrical separator 3 and the partial cutout portion 5c of the bottom separator 5 do not overlap. 5 above.

  Further, by inserting a core wound with the cylindrical separator 3 (details will be described later) in the direction of the opening of the battery case 1, as shown in FIG. 5 is wrapped with a rising portion 5b where the peripheral edge of 5 is bent. In this state, the hollow cylindrical positive electrode material 2 housed in the battery case 1 is attached in close contact with the inner diameter.

  By attaching the partial separator 5c of the bottom separator 5 and the winding start position 3b and the winding end position 3c of the cylindrical separator 3 so as not to overlap, the negative electrode material 4 flows out from the partial cut part 5c of the bottom separator 5 at the time of mounting. Therefore, it is possible to improve the reliability without causing leakage or internal short circuit, and the winding start position 3b, the winding end position 3c of the cylindrical separator 3 and the folding portion 5e of the bottom separator 5 are overlapped. It is also possible to suppress a phenomenon in which the capacity of the negative electrode material 4 is reduced. Furthermore, the inter-electrode distance between the positive electrode material 2 and the negative electrode material 4 via both separators 3 and 5 is reduced, and variations in battery internal resistance can be suppressed. 2 may be a seamless cylindrical separator 3 having no bottom, and when the cylindrical separator 3 and the bottom separator 5 are mounted, complicated folding due to bending of the bottom separator 5 cannot be performed. The decrease in capacity is suppressed, and the discharge characteristics can be improved.

  Further, since the bottom separator 5 and the cylindrical separator 3 are inserted and mounted without misalignment, the bottom separator 5 is squeezed with the center symmetrical, and the bottom of the battery case 1 covers the bottom separator 5, An internal short circuit between the negative electrode material 4 and the bottom surface of the battery case 1 when the gelled negative electrode material 4 is filled in a later step is prevented.

  Thereafter, an electrolyte solution (not shown) is injected as shown in the structure of FIG. 1 and a gelled negative electrode material 4 is inserted. Then, an insulating gasket 7 is attached to the periphery, and a negative electrode current collecting rod is provided at the center. The negative electrode current collecting rod 9 of the sealing plate 8 serving as the negative electrode terminal provided with 9 is inserted into the negative electrode material 4 while being attached to the opening portion of the battery case 1, and the opening portion of the battery case 1 is bent inward to be caulked and sealed. A sealed cylindrical battery is produced.

  Note that the gelled negative electrode material 4 comprises sodium polyacrylate as a gelling agent, a 40 wt% aqueous sodium hydroxide solution as an alkaline electrolyte, and zinc powder as a negative electrode active material in a weight ratio of 1:33:66. Mixed.

  The configuration and manufacturing method of the cylindrical battery according to the embodiment of the present invention will be described in detail below. About the structure and manufacturing method shown below, an example is shown as an AA (LR6) which is an alkaline manganese dry battery having an outer diameter of 14 mm and a height of 50 mm, which is listed for explaining the present invention. The structure of the cylindrical battery is not specified as follows.

(Embodiment 1)
As shown in FIG. 5 (a), the bottom separator 5 has a thickness of 0.2 mm and a width of 15 mm of the dotted line portion shown in the figure, which is the same as the width dimension of the strip-shaped separator 18 processed from a non-woven fabric having a width of 15 mm. At the same time, a partially cut portion 5c was formed so that the partially cut portion did not come inside the outer diameter of the cylindrical separator 3, thereby forming a rectangular bottom separator 5.

  As shown in FIG. 5 (b), in the state where the center of the bottomed cylindrical battery case 1 containing two cylindrical positive electrode materials 2 made of manganese dioxide in the previous step and the center of the bottom separator 5 are matched. A bottom separator 5 is disposed in the opening of the battery case 1. Further, the corner 5a of the bottom separator 5 is positioned.

  Further, as shown in FIG. 6A, a strip separator 36 having a thickness of 0.2 mm and a width of 44 mm is cut into a length of 85 mm at the dotted line portion shown in the figure, and the core 16 is cut as shown in FIG. 6B. A cylindrical separator 3 consisting of 3 rolls was formed.

  By making the width of the strip separator 36 the same as the height of the cylindrical separator 3 and further cutting out into a square at the dotted line portion shown in the figure, there is no material loss and no chips are generated, so that the waste disposal work process can be omitted. it can.

  Further, the winding start position 3b and the winding end position 3c of the cylindrical separator 3 shown in FIG. 6 (c) are dimensions such that the winding end position 3c finishes winding at the same position as the winding start position 3b as shown in FIG. 6 (b). After the strip separator 36 is cut and the winding start position 3b is determined, the winding core 16 is rotated, and when the strip separator 36 is wound, the winding start position 3b is determined, so that the winding end position 3c is naturally determined. .

  Further, when the strip separator 36 is wound to form the cylindrical separator 3, a guide is preferably provided on the core 16, and a freely rotating object such as a roller is pressed against the core 16 via the strip separator 36. It is more preferable to assist the winding. In addition, after completing the required number of turns, the tubular separator 3 may be formed by cutting.

  After forming the cylindrical separator 3 in which the winding end position 3c is positioned, the winding end position 3c of the cylindrical separator 3 is positioned so that the partially cut portion 5c of the bottom separator 5 does not overlap as shown in FIG. 6 (d). In this state, the core 16 around which the cylindrical separator 3 is wound is lowered, and the bottom separator is placed on the bottom surface of the battery case 1 while pressing the central portion of the bottom separator 5 where the corner 5a is positioned at the front end surface of the core 16. Inserted until 5 abuts.

  At this time, the cylindrical separator 3 is inserted into the battery case 1 in a state of being wrapped by the bottom separator 5 and inserted until the bottom separator 5 comes into contact with the bottom surface of the battery case 1. Further, it is preferable to install a guide hole so that the cylindrical separator 3 wound around the core 16 does not loosen, and if it is inserted into the battery case 1 while passing through the guide hole, no loosening occurs. .

  Further, since there is no deviation between the center of the bottom separator 5 and the core 16, the bottom separator 5 is squeezed symmetrically about the center and attached so as to cover the bottom of the battery case 1, so that a gel-like shape is formed in a later step. Short circuit with the battery case 1 and the positive electrode material 2 when the negative electrode material 4 is filled can be suppressed with high accuracy.

  After accommodating the cylindrical separator 3 and the bottom separator 5 in the state as shown in FIG. 3 (c) in the battery case 1, an electrolyte is injected into the battery case 1 as shown in FIG. After inserting the gel-like negative electrode material 4 and attaching the sealing plate 8 to the opening of the battery case 1, the opening of the battery case 1 is bent inward and caulked, sealed and sealed. A dry battery 10 was produced.

  As described above, according to the present invention, the cylindrical separator 3 is formed from the outside by the rectangular bottom separator 5 having the partial cutout portion 5c for preventing the bending wrinkle generated by bending along the cylindrical shape of the cylindrical separator 3. In the case of using a cylindrical separator 3 configured to be wrapped and wound a plurality of times, a part of a rectangular bottom separator 5 having a winding start position 3b, a winding end position 3c, and a partial cutout part 5c of the cylindrical separator 3 By positioning the tubular separator 3 so as to wrap the tubular separator 3 with the bottom separator 5 so as not to overlap with the cut portion 5c, a partial cut portion of the bottom separator 5 when the tubular separator 3 and the bottom separator 5 are mounted. 5c does not cause the complicated folding overlapped at the rising portion 5b, but the folded folding formed by the partial cutout portion 5c of the bottom separator 5 Since the overlapping part 5e does not overlap the winding start position 3b and the winding end position 3c of the cylindrical separator 3, it is possible to insert the bottom separator 5 with high accuracy, without causing leakage or internal short circuit. Realizes stable supply and safety of cylindrical batteries with high capacity and reliability.

  According to the present invention, the cylindrical separator is configured to be wrapped from the outside with a rectangular bottom separator having a partially cut-out portion that prevents folding wrinkles generated by bending along the cylindrical shape of the cylindrical separator. Therefore, it is possible to suppress a decrease in the capacity of the negative electrode material due to the complicated folding of the bottom separator, and the position of the folded portion of the bottom separator is determined in advance so that the distance between the positive electrode material and the negative electrode material is reduced. As a result, the variation in internal resistance and the discharge characteristics are improved. In addition, since the bottom cut-off portion of the bottom separator and the winding start position and the winding end position of the cylindrical separator are not overlapped, the negative electrode material does not flow out from the partial cut-out portion of the bottom separator at the time of mounting. It is possible to improve reliability without causing internal short circuit, and to obtain a high-capacity, high-quality, reliable cylindrical battery, and portable information devices and digital devices that require high load discharge performance. It is useful as a power source for high-current discharge devices such as cameras.

Half sectional front view of a cylindrical battery in an embodiment of the present invention (A) Schematic diagram of a bottom separator and a seamless tubular separator without a bottom in the embodiment of the present invention, (b) A schematic diagram showing a state where the bottom separator is wrapped with a seamless tubular separator without a bottom. (C) A schematic diagram in which the shape of the partially cut portion provided in the bottom separator is a U shape, (d) a schematic diagram in which the shape of the partial cut portion provided in the bottom separator is a letter shape, and (e). Schematic with an R shape at the apex of the partially excised part provided in the bottom separator (A) Schematic diagram of a bottom separator and a cylindrical separator wound a plurality of times in the embodiment of the present invention, (b) a plan view of the bottom separator and a cylindrical separator wound a plurality of times, (c) a bottom separator The schematic diagram which shows the state which wrapped the cylindrical separator wound in multiple times with The top view of the cylindrical separator wound in multiple times so that it may become the same position as a bottom separator and a winding start position in the embodiment of the present invention (A) Schematic diagram of a strip-shaped separator before forming into the shape of the bottom separator, (b) Schematic diagram before inserting the bottom separator. (A) Schematic diagram of the strip separator before being molded into the cylindrical separator, (b) Schematic diagram showing the state before molding the cylindrical separator, (c) Schematic showing the state of molding the cylindrical separator FIG. 4D is a schematic diagram showing a state before the cylindrical separator and the bottom separator are inserted. Half sectional front view of cylindrical battery in conventional example (A) Schematic diagram showing the winding state of the cylindrical separator in the conventional example, (b) Schematic diagram showing the state when the bottom separator and the cylindrical separator are inserted, (c) Mounting of the bottom separator and the cylindrical separator Schematic diagram of time The schematic diagram which shows the state which wrapped the cylindrical separator with the bottom part separator in a prior art example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Battery case 2 Positive electrode material 3 Cylindrical separator 3b Winding start position 3c Winding end position 4 Negative electrode material 5 Bottom part separator 5a Corner | angular part 5b Rising part 5c Partial cut-off part 5d Side intermediate part 5e Folding part 5f R shape 6 Positive electrode convex part 7 Insulating gasket 8 Sealing plate 9 Negative electrode current collector rod 10 Alkaline manganese dry cell 12 Overlapping portion 16 Core 18 Strip separator 36 Strip separator

Claims (20)

In a cylindrical battery in which a positive electrode material, a negative electrode material, a cylindrical separator interposed between the positive electrode material and the negative electrode material, and a bottom separator that wraps an end of the cylindrical separator are housed in a cylindrical battery case The bottom separator has a partial cut-out portion for preventing bending wrinkles generated when the bottom separator is bent along the cylindrical shape of the cylindrical separator, and is configured to wrap the cylindrical separator from the outside. Battery. The cylindrical battery according to claim 1, wherein the bottom separator has a rectangular shape. 2. The cylindrical battery according to claim 1, wherein at least two of the partially cut portions are opposed to each other. 2. The cylindrical battery according to claim 1, wherein a winding end position of a cylindrical separator configured by winding the partially cut portion and a cylindrical shape does not overlap. A portion where the winding end position and the winding start position of the cylindrical separator are overlapped with each other, and a folded portion of the partially cut portion of the bottom separator folded so as to wrap along the cylindrical shape of the cylindrical separator do not overlap. The cylindrical battery according to claim 1, which is configured. The cylindrical battery according to claim 1, wherein a winding start position and a winding end position of the cylindrical separator are the same position. 2. The cylindrical battery according to claim 1, wherein the partial cut portion is disposed so as to be positioned outside an outer diameter of the cylindrical separator when the bottom separator and the cylindrical separator are overlapped. The cylindrical battery according to claim 1, wherein the partial cut portion is V-shaped. The cylindrical battery according to claim 1, wherein a shape of the partial cut portion is a letter shape. The cylindrical battery according to claim 8 or 9, wherein an apex of the partial cut portion is provided with an R shape. The cylindrical battery according to claim 1, wherein the partially cut portion is U-shaped. The cylindrical battery according to claim 2, wherein a partial cut portion is provided in an intermediate portion of the side of the bottom separator. The cylindrical battery according to claim 4, wherein the partial cut portion is arranged so as to sandwich a winding end position of the cylindrical separator. The cylindrical battery according to claim 1, wherein a positive electrode mixture made of manganese dioxide and molded into a hollow cylindrical shape is used as the positive electrode material. The cylindrical battery according to claim 1, wherein a microporous film that transmits ions is used as the bottom separator. 2. The cylindrical battery according to claim 1, wherein the bottom separator has a shape larger than the outer diameter of the cylindrical separator. The cylindrical battery according to claim 1, wherein a microporous film that transmits ions is used as the cylindrical separator. A first step of storing a cylindrically formed positive electrode material in a bottomed cylindrical battery case, a second step of inserting a bottom separator and a cylindrical tubular separator, and an electrolyte and a gelled negative electrode material A cylindrical battery manufacturing method comprising a third step of inserting a battery and a fourth step of arranging a sealing body provided with a negative electrode current collector rod at the opening of the battery case and caulking and sealing the opening of the battery case. In the second step, after forming a partially cut portion in the bottom separator, the bottom separator and the cylindrical separator are simultaneously inserted so as to wrap the cylindrical separator from the outside with the bottom separator. Battery manufacturing method. In the second step, a cylindrical separator is formed by winding a strip-shaped separator, and positioned so that the winding end position of the cylindrical separator and the partial cut portion of the bottom separator do not overlap. The method for manufacturing a cylindrical battery according to claim 18, wherein the bottom separator and the cylindrical separator are simultaneously inserted so that the cylindrical separator is wrapped from the outside by the bottom separator. As a bottom separator, a strip-shaped separator is cut into a square shape so that the lengths of four sides have the same dimensions, and a part of the middle part of the side of the bottom separator is cut to form a partially cut portion. The method for producing a cylindrical battery according to claim 18.

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