JP6142521B2 - Cylindrical battery - Google Patents

Description

  The present invention relates to a cylindrical battery.

  As a conventional cylindrical battery, as shown in Patent Document 1, a cylindrical electrode is formed by winding a belt-like positive electrode plate and a negative electrode plate in a spiral shape through a belt-like separator around a cylindrical battery case. Some have housed groups.

  However, when the belt-like positive electrode plate, negative electrode plate, and separator are wound in a spiral shape, the positive electrode plate and the negative electrode plate are unwound in the winding process. If it does so, problems, such as not being able to obtain a desired battery capacity in a cylindrical battery and causing an internal short circuit, will arise.

Japanese Patent Laid-Open No. 11-185767

  Therefore, the inventor of the present application considers accommodating a stacked electrode group in a cylindrical battery in order to solve various problems associated with winding misalignment and winding misalignment.

  However, when a stacked electrode group is accommodated in a cylindrical battery, for example, an electrode group having a substantially rectangular parallelepiped shape is accommodated in the cylindrical battery case. Therefore, there is a problem that the active material of the electrode plate falls off and the charge / discharge performance deteriorates.

  In order to eliminate the shakiness of the electrode group, the inventor of the present application considers fixing the electrode group to the battery case using a spacer. Then, as shown in FIG. 10, the inventor of the present application extends from the other surface of the electrode contact portion and the electrode contact portion having a contact surface that contacts the outer surface of the electrode group, as shown in FIG. The thing provided with the case contact part which contacts the inner peripheral surface of a case over the upper and lower sides is considered.

  However, in the above configuration, the space formed by the inner peripheral surface of the battery case and the outer surface of the electrode group is partitioned by the case contact portion. If it does so, even if electrolyte solution is inject | poured into one space partitioned off by the case contact part, the malfunction that electrolyte solution does not flow into other space will arise. For this reason, if a predetermined amount of electrolytic solution to be stored in the battery case is injected at once, the electrolytic solution overflows from the battery case. On the other hand, in order to prevent the electrolyte from overflowing, it is necessary to divide the electrolyte into a plurality of times, and there is a problem that workability is poor.

  Therefore, the present invention has been made to solve the above-described problems, and provides a cylindrical battery that is not only resistant to an increase in the internal pressure of the battery but also does not require consideration of winding deviation of the electrode group. In addition to fixing the electrode group to the battery case using a spacer in the battery, the main objective is to improve the surroundings of the electrolyte solution.

  That is, the cylindrical battery according to the present invention includes a cylindrical battery case, a positive electrode, a negative electrode, and a separator, which are disposed in the battery case, and a pair of outer surfaces facing each other are planar electrodes. And a spacer provided between an inner peripheral surface of the battery case and a planar outer surface of the electrode group, the spacer extending from one axial end to the other axial end. It has a case contact portion that is continuously provided and contacts the inner peripheral surface of the battery case, and the case contact portion is formed with a communication portion that communicates a space partitioned by the case contact portion. And

  If it is such, since the electrode group which consists of a positive electrode, a negative electrode, and a separator and makes a pair of opposing outer surfaces form a planar shape is accommodated in the battery case, it accompanies winding deviation and winding deviation of the electrode group. A battery free from various problems can be provided. Moreover, since it is a cylindrical battery case, it can be strengthened in strength against an increase in internal pressure. Moreover, since the electrode group is fixed by the spacer, it is possible to prevent the electrode group from rattling with respect to the battery case, and it is possible to prevent the active material from falling off the electrode plate and prevent deterioration of charge / discharge performance. . Furthermore, since the communication part which connects the space partitioned by the said case contact part is formed in the case contact part which contacts the inner peripheral surface of a battery case, electrolyte solution is provided in one space partitioned by the case contact part, for example When the electrolyte is injected, the injected electrolyte flows into the other space through the communication portion, and the circumference of the electrolyte can be improved. In addition, since the case contact portion is provided continuously from one end in the axial direction to the other end in the axial direction in the spacer, the mechanical strength of the spacer can be increased. For example, when assembling a cylindrical battery The work in can be facilitated.

  It is desirable that a plurality of the communication portions are formed in the case contact portion along the axial direction. Thus, by forming a communication part in several places along an axial direction, the circumference of the liquid in the injection of electrolyte solution can be improved further.

  It is desirable that the communication portion is a recess formed in a free end side portion that contacts the inner peripheral surface of the battery case in the case contact portion. Since the communication space is formed by the inner peripheral surface and the concave portion of the battery case by configuring the communication portion by the concave portion in this way, the electrolyte solution flows along the inner peripheral surface of the battery case. The circumference of the liquid can be further improved.

  The communication part is preferably a through hole formed in the case contact part. By configuring the communication portion with the through hole in this way, substantially the entire free end side portion of the case contact portion comes into contact with the inner peripheral surface of the battery case, and the electrode group is more reliably fixed by the spacer. be able to. In addition, by not forming a recess in the free end side portion of the case contact portion, it is possible to facilitate the operation of inserting the spacer into the battery case when assembling the cylindrical battery.

  The spacer has an electrode contact portion having a contact surface on one surface that contacts the outer surface of the electrode group, and the case contact portion is one end in the axial direction of the electrode contact portion on the other surface of the electrode contact portion. It is desirable to extend continuously from the other end in the axial direction. If this is the case, a vertically communicating space can be formed by the other surface of the electrode contact portion, the side surface of the case contact portion, and the inner peripheral surface of the battery case, and a space for accommodating an electrolytic solution can be secured. In addition, in the case where the electrolytic solution is injected into a space communicating vertically, the improvement effect around the liquid can be made more remarkable by forming the communication portion in the case contact portion.

  It is desirable that at least two case contact portions are formed in parallel along the central axis direction on the other surface of the electrode contact portion. At this time, it is desirable that communication portions are formed in all case contact portions. Further, it is desirable that the two case contact portions are provided symmetrically so as to sandwich the central axis. If this is the case, the electrode contact portion can be uniformly pressed against the electrode group by the case contact portion in contact with the inner peripheral surface of the battery case, and the charge / discharge efficiency can be improved. In addition, when the two case contact portions are formed away from the central portion in the width direction, a large space can be taken between the electrode contact portion and the battery case, so that the current collecting terminal is easily welded to the battery case. At the same time, the electrolyte can be easily injected. Also, by pouring the electrolyte into the space between the two case contact parts, the electrolyte flows into the two spaces adjacent to the space via the communicating part, so that the periphery of the electrolyte solution is further increased. Can be improved.

  According to the present invention configured as described above, a cylindrical battery that is not only resistant to an increase in the internal pressure of the battery but also does not need to consider the winding deviation of the electrode group is provided, and a spacer is used in the cylindrical battery. In addition to fixing the electrode group to the battery case, it is possible to improve the periphery of the electrolyte in the electrolyte injection.

The longitudinal cross-sectional view of the cylindrical battery in this embodiment. The cross-sectional view of the cylindrical battery in the same embodiment. The top view, front view, and perspective view which show the positive electrode plate of the embodiment. The top view, front view, and perspective view which show the negative electrode plate of the embodiment. The longitudinal cross-sectional view of the electrode group of the embodiment. The perspective view which shows the spacer of the embodiment. The partial enlarged front view of the spacer of the embodiment. The figure which shows the state which accommodated the spacer and electrode group of the embodiment in the battery case. The perspective view which shows the spacer of deformation | transformation embodiment. Sectional drawing which shows an example of the spacer used as the basic composition of this invention.

  An embodiment of a cylindrical battery according to the present invention will be described below with reference to the drawings.

  The cylindrical battery 100 according to the present embodiment is an alkaline storage battery such as a nickel / cadmium storage battery or a nickel / hydrogen storage battery. Specifically, as shown in FIGS. 1 and 2, a metal battery case 2 having a bottomed cylindrical shape, and a positive electrode plate 31, a negative electrode plate 32, and a separator 33 are arranged in the battery case 2. The electrode group 3 has a substantially rectangular parallelepiped shape.

  The battery case 2 has a bottomed cylindrical shape with nickel plating, and the upper opening is sealed with a sealing body 5 via an insulator 4 as shown in FIG. Further, a current collecting terminal 311 provided so as to protrude from the upper end portion of the positive electrode plate 31 is connected to the back surface of the sealing body 5 by, for example, welding directly or via a current collecting plate (not shown). It becomes the positive terminal. In this embodiment, as will be described later, the current collecting terminal 321 of the negative electrode plate 32 of the electrode group 3 is welded to the bottom surface 2B of the battery case 2.

  The electrode group 3 has a substantially rectangular parallelepiped shape in which a positive electrode plate 31 and a negative electrode plate 32 are laminated via a separator 33 made of, for example, a nonwoven fabric made of polyolefin. The separator 33 is impregnated with an electrolytic solution such as potassium hydroxide.

  The positive electrode plate 31 is filled with a positive electrode current collector made of foamed nickel and a mixture of a nickel hydroxide active material and a cobalt compound of a conductive material (hereinafter simply referred to as a positive electrode active material) in the hollow of the positive electrode current collector. It is a thing. The nickel hydroxide active material is, for example, nickel hydroxide in the case of a nickel / cadmium storage battery, and nickel hydroxide to which calcium hydroxide is added in the case of a nickel / hydrogen storage battery.

  Specifically, as shown in FIG. 3, the positive electrode plate 31 is formed on both sides of a linear active material non-holding portion 31A that does not hold a positive electrode active material and the active material non-holding portion 31A. Active material holding portion 31B. In the positive electrode plate 31, the positive electrode current collector is bent in a substantially U shape (more specifically, a substantially U shape) in the active material non-holding portion 31A so that the active material holding portions 31B on both sides face each other. .

  Further, the positive electrode plate 31 is provided with a current collecting terminal 311 made of, for example, a nickel steel plate, in an active material non-holding portion 31A that is a bent portion formed between two active material holding portions 31B. The current collecting terminal 311 extends outward in one of the width directions orthogonal to the opposing direction of the two active material holding portions 31B.

The negative electrode plate 32 is made of, for example, a negative electrode current collector made of a flat perforated steel sheet plated with nickel, and a negative electrode active material coated on the negative electrode current collector. The negative electrode active material is, for example, a mixture of cadmium oxide powder and metal cadmium powder in the case of a nickel-cadmium storage battery, and mainly in the case of a nickel-hydrogen storage battery, for example, AB type ₅ (rare earth) or is a powder of hydrogen absorbing alloy of AB ₂ type (Laves phase).

  Specifically, as shown in FIG. 4, the negative electrode plate 32 has a linear active material non-holding portion (uncoated portion) 32A that does not hold the negative electrode active material, and both sides of the active material non-holding portion 32A. An active material holding part (coating part) 32B that is formed and holds the negative electrode active material. In the negative electrode plate 32, the negative electrode current collector is bent in a substantially U shape in the active material non-holding portion 32A so that the active material holding portions 32B on both sides face each other.

  Further, the negative electrode plate 32 is formed with a current collecting terminal 321 welded to the bottom surface 2B of the battery case 2 by bending a part of the active material non-holding portion 32A outward. Specifically, the current collection terminal 321 is formed by making a cut 32C in a part of the active material non-holding portion 32A so as to have a desired current collection terminal shape and bending the inside of the cut 32C outward. .

  The electrode group 3 of the present embodiment has a substantially U-shaped positive electrode plate 31 in which two active material holding portions 31B are arranged to face each other, and an approximately U shape in which two active material holding portions 32B are arranged to face each other. The negative electrode plate 32 having a U-shape is laminated so as to mesh with each other. The positive electrode plate 31 is bent in a substantially U shape while being sandwiched between the folded separators 33. Specifically, as shown in FIG. 5, one active material holding part 31 </ b> B of the positive electrode plate 31 is sandwiched between two active material holding parts 32 </ b> B of the negative electrode plate 32 and one active material of the negative electrode plate 32. The holding part 32 </ b> B is stacked so as to be sandwiched between the two active material holding parts 31 </ b> B of the positive electrode plate 31. In the present embodiment, the bent portion (active material non-holding portion 31A) of the positive electrode plate 31 and the bent portion (active material non-holding portion 32A) of the negative electrode plate 32 are laminated so as to face each other. In FIG. 1, FIG. 2, FIG. 5, etc., for ease of understanding, the electrode plates 31 and 32 and the separator 33 are illustrated with an interval, but they are stacked in contact with each other. .

  More specifically, the electrode group 3 of the present embodiment is composed of two negative plates 32 and one positive plate 31, and each of the two adjacent negative plates 32 has one active material holding portion 32 </ b> B. The active material holding portions 32B adjacent to each other in the two negative electrode plates 32 are stacked so as to be sandwiched between the two active material holding portions 31B of one positive electrode plate 31. Therefore, in the electrode group 3 of the present embodiment, the entire outer surfaces 32a and 32b of the negative electrode plate 32 are exposed to form the outermost surface. The electrode group 3 is housed in the battery case 2 so that the stacking direction L is orthogonal to the central axis direction C of the battery case 2 as shown in FIGS.

  And the cylindrical battery 100 of this embodiment has the spacer 6 for fixing the electrode group 3, as shown in FIG.1 and FIG.2. The spacer 6 is a pair of spacers 61 and 62 that are provided between the inner peripheral surface 2 A of the battery case 2 and the outer surface of the electrode group 3 and fix the electrode group 3 to the battery case 2. The pair of spacers 61 and 62 are disposed in a space between the inner peripheral surface 2A of the battery case 2 and the outer surface of the electrode group 3 so as to sandwich the electrode group 3 from the stacking direction L. . Note that the stacking direction L coincides with the facing direction of the active material holding portions 31B and 32B of the electrode plates 31 and 32, respectively.

  The pair of spacers 61 and 62 are made of resin such as acrylic resin, polypropylene resin, nylon resin, or metal such as stainless steel, and have the same shape.

  As shown in FIGS. 1, 2, and 6, each spacer 61, 62 is a contact surface that contacts the outermost surface in the stacking direction L of the electrode group 3 (specifically, the outer surfaces 32 a, 32 b of the negative electrode plate 32). A rectangular flat plate electrode contact portion 6A on one surface 6a, and two case contact portions 6B extending from the other surface 6b of the electrode contact portion 6A and contacting the inner peripheral surface 2A of the battery case 2.

  The electrode contact portion 6 </ b> A has a shape along the outermost surface in the stacking direction L of the electrode group 3. As shown in FIGS. 1 and 6 to 8, a protruding piece 6 </ b> T facing the upper surface of the electrode group 3 is formed on the upper portion, which is one axial end portion of the electrode contact portion 6 </ b> A. The protruding piece 6T extends substantially vertically from the electrode contact portion 6A at the center of the upper end of the electrode contact portion 6A. The projecting piece 6T contacts the current collecting terminal 311 extending upward from the upper surface of the electrode group 3 to prevent the current collecting terminal 311 from being displaced and the welded portion of the current collecting terminal 311 is broken and peeled off. It is intended to prevent this.

  Moreover, the surrounding wall part 6P which surrounds the upper corner | angular part of the electrode group 3 is formed in the corner | angular part of the upper part of 6 A of electrode contact parts as shown in FIGS. The surrounding wall portion 6P includes an upper wall 6P1 that faces the upper surface of the electrode group 3 and a side wall 6P2 that faces the left and right side surfaces of the electrode group 3 (see FIG. 7). The surrounding wall 6P prevents contact between the battery case 2 and the positive electrode plate 31 and prevents contact between the current collecting terminal 311 of the positive electrode plate 31 and the negative electrode plate 32. Further, the surrounding wall portion 6P can prevent the positive electrode plate 31 and the negative electrode plate 32 from being displaced in the electrode group 3. In addition, by providing the surrounding wall portion 6P, it is not necessary to dispose an upper insulating plate, which has been essential in the past, so that the manufacturing process can be simplified and the material cost can be reduced.

  The two case contact portions 6B are formed in parallel with each other along the central axis direction C on the other surface 6b of the electrode contact portion 6A. Specifically, the battery case 2 is formed symmetrically so as to sandwich the central axis of the battery case 2 in a state of being accommodated in the battery case 2. Furthermore, the contact portion (tip surface of the free end side portion) of the case contact portion 6B with the inner peripheral surface 2A of the battery case 2 has a curved surface that is substantially the same as the curved surface of the inner peripheral surface 2A of the battery case 2. Thus, the case contact portion 6B and the battery case 2 are configured to be in surface contact (see FIGS. 2 and 8). Each case contact portion 6B is provided so as to continuously extend from the upper portion, which is one end portion in the axial direction, to the lower portion, which is the other end portion in the axial direction, on the other surface 6b of the electrode contact portion 6A (see FIG. 1 and FIG. (See FIG. 6).

  When such a spacer 6 is used to place the electrode group 3 in the battery case 2, the current collecting terminal 311 of the positive electrode plate 31 is contacted or projected by the protruding pieces 6T of the two spacers 6 as shown in FIG. Pressed. It should be noted that the free end portion side of the current collecting terminal 311 is bent with respect to the protruding piece 6T and welded to the sealing body 5. Here, the rising position of the current collecting terminal 311 is in the vicinity of the protruding piece 6T. Further, the upper corner portions of the positive electrode plate 31 and the negative electrode plate 32 are accommodated by the surrounding wall portions 6P of the two spacers 6. Further, a recess formed between the electrode contact portion 6A and the case contact portion 6B becomes a welding space, and the current collecting terminal 321 of the negative electrode plate 32 can be welded to the bottom surface 2B of the battery case 2 by the welding space.

  In addition, the case contact portion 6 </ b> B contacts the inner peripheral surface 2 </ b> A of the battery case 2 while being accommodated in the battery case 2, and the outer surface of the electrode group 3 and the inner peripheral surface 2 </ b> A of the battery case 2. The space formed between the upper and lower sides is partitioned, and spaces that communicate with each other are formed on both sides of each case contact portion 6B (see FIGS. 1 and 2). The spacers 61 and 62 of the present embodiment have two case contact portions 6B and are partitioned into three spaces by the two case contact portions 6B and the inner peripheral surface 2A of the battery case 2.

  And each case contact part 6B of this embodiment has the communication part 6X which connects the space partitioned off by the said case contact part 6B, as shown in FIG.1, FIG2 and FIG.6.

  The communication portion 6X communicates adjacent spaces via the case contact portion 6B, facilitates liquid movement in the adjacent spaces, and facilitates the periphery of the electrolyte solution. Further, the communication portion 6X is formed at a plurality of locations along the axial direction in the free end side portion of the case contact portion 6B (the portion that contacts the inner peripheral surface 2A of the battery case 2). In the present embodiment, two communication portions 6X are formed in the lower half of the case contact portion 6B. Thus, since it has provided in the lower half of case contact part 6B, when electrolyte solution is poured at once, before electrolyte solution leaks from the upper opening of battery case 2, electrolyte solution is connected via communication part 6X. Can flow into another adjacent space, and the electrolyte can be prevented from leaking out.

  A specific configuration of the communication portion 6X is a recess formed in the free end side portion that contacts the inner peripheral surface 2A of the battery case 2 in the case contact portion 6B. The two recesses 6X formed in each case contact portion 6B communicate with one side surface and the other side surface of the case contact portion 6B and have the same shape. Moreover, the depth of each recessed part 6X shall be smaller than the extension length of the said case contact part 6B. That is, the recess 6X is formed so as not to be continuous with the electrode contact portion 6A. The extension length is a length from the base end continuous to the electrode contact portion 6A in the case contact portion 6B to the free end contacting the battery case 2. The recess 6 </ b> X forms a communication space with the inner peripheral surface 2 </ b> A of the battery case 2. As a result, when an electrolyte is injected into a predetermined space partitioned by the case contact portion 6B, the electrolyte that has flowed into the space flows along the inner peripheral surface 2A of the battery case 2 and is adjacent to another space. Easy to flow into the space.

  Further, the recesses 6X formed in the two case contact portions 6B are formed at the same height. Thereby, when electrolyte solution is poured into the space formed between the two case contact portions 6B, the electrolyte solution flows in substantially the same amount in the space on both sides thereof, and the electrolyte solution flows in one of the spaces. To prevent bias.

  In the present embodiment, a recess for inserting a liquid injection nozzle (not shown) for injecting an electrolyte into the upper part of a portion sandwiched between two case contact portions 6B on the other surface 6b of the electrode contact portion 6A. 6M is formed (see FIGS. 1 and 6). The recess 6M is formed between the two case contact portions 6B over a predetermined range from the upper surface of the electrode contact portion 6A. Further, the lower inner surface of the recess 6M is an inclined surface 6Ma for guiding the electrolytic solution discharged from the liquid injection nozzle downward. In this way, the lower inner surface of the recess 6M is the inclined surface 6Ma, so that the electrolytic solution discharged from the liquid injection nozzle is prevented from splashing and scattering to the outside of the battery case 2.

  Next, a method for manufacturing the cylindrical battery 100 configured as described above will be briefly described.

  The electrode group 3 described above is sandwiched between the pair of spacers 61 and 62 from the stacking direction L. The structure thus formed is placed in the battery case 2. In addition, the collector terminal 321 of the negative electrode plate 32 is positioned between the two case contact portions 6B of the pair of spacers 61 and 62 while the lower surface of the case contact portion 6B of the spacers 61 and 62 is the current collector. A part of the terminal 321 is pressed against the bottom surface 2 </ b> B of the battery case 2. In addition, after accommodating the electrode group 3 in the battery case 2, the pair of spacers 61 and 62 may be accommodated so as to sandwich the electrode group 3.

  Then, with the electrode group 3 fixed to the battery case 2, a welding rod is inserted into the space formed between the case contact portion 6B of the spacers 61 and 62 and the inner peripheral surface 2A of the battery case 2, and the negative electrode plate 32 current collecting terminals 321 are connected to the bottom surface 2B of the battery case 2 by welding. Thereafter, an electrolytic solution is injected into the battery case 2.

  This liquid injection is performed, for example, in a space formed between the two case contact portions 6B in either one of the spacers 61, and the tip of the liquid injection nozzle is inserted up to the recess 6M. And the electrolyte solution which came out of the liquid injection nozzle is guide | induced below along the inclined surface 6Ma of the hollow part 6M, and flows in into the space between the two case contact parts 6B. In addition, the injected electrolyte flows through the communication portion 6X formed in the two case contact portions 6B and flows into two adjacent spaces via the case contact portion 6B. Then, the electrolyte flowing into the two adjacent spaces flows through the space between the electrode group 3 and the battery case 2 to the other spacer 62 side, and the case contact portion 6B of the other spacer 62 It flows into the space formed between the two case contact portions 6B in the other spacer 62 via the communication portion 6X. Thereby, the periphery of the electrolyte solution at the time of pouring can be quickly performed, and the electrolyte solution can be spread in the battery case 2 by a single pouring. And after pouring, while the current collection terminal 311 of the positive electrode plate 31 is connected to the back surface of the sealing body 5 directly or through a current collection board (not shown), the said sealing body 5 is connected to the battery case 2 via the insulator 4. It is fixed to the upper opening of the door by caulking or the like.

<Effect of this embodiment>
According to the cylindrical battery 100 according to the present embodiment configured as described above, the electrode group 3 in which the positive electrode plate 31 and the negative electrode plate 32 are stacked via the separator 33 is accommodated in the battery case 2, so that the electrode group 3 It is possible to provide a battery that is free from various problems associated with winding misalignment and winding misalignment. Moreover, since it is the cylindrical battery case 2, it can be strengthened in strength against the increase in internal pressure.

  Further, since the electrode group 3 is pressed and fixed in the battery case 2 using the spacers 61 and 62, rattling of the electrode group 3 with respect to the battery case 2 can be prevented, and the electrode plates 31 and 32 can be prevented. In addition to preventing the active material from falling off and preventing the deterioration of the charge / discharge performance, the charge / discharge performance can be improved.

  In particular, the case contact portion 6B of the spacers 61 and 62 is formed with a communication portion (concave portion) 6X that communicates the space partitioned by the case contact portion 6B. Therefore, in one space partitioned by the case contact portion 6B When the electrolytic solution is injected, the injected electrolytic solution flows into the other space through the communication portion (recessed portion) 6X, and the circumference of the electrolytic solution can be improved. Thereby, even if a predetermined amount of electrolytic solution to be accommodated in the battery case 2 is injected at once, the electrolytic solution can be prevented from overflowing from the battery case 2, and the electrolytic solution can be injected. It is no longer necessary to carry out the process in a plurality of times, and the workability of the liquid injection work can be improved. In addition, since the case contact portion 6B is provided continuously from one axial end to the other axial end on the other surface 6b of the electrode contact 6A, the mechanical strength of the spacers 61 and 62 is increased. For example, the work at the time of assembling the cylindrical battery 100 can be facilitated.

<Other modified embodiments>
The present invention is not limited to the above embodiment.

  For example, in the above-described embodiment, the communication portion 6X of the case contact portion 6B is a recess formed in the free end side portion. However, as shown in FIG. 9, the communication portion 6X includes a through hole formed in the case contact portion 6B. doing. This through-hole penetrates in the thickness direction of the case contact portion 6B and opens to one side surface and the other side surface of the case contact portion 6B. By forming the communication portion 6X by the through hole in this manner, substantially the entire free end side portion of the case contact portion 6B comes into contact with the inner peripheral surface 2A of the battery case 2, and the electrode group is formed by the spacers 61 and 62. 3 can be further secured. Further, by not forming a recess in the free end side portion of the case contact portion 6B, it is possible to facilitate the operation of inserting the spacers 61 and 62 into the battery case 2 when assembling the cylindrical battery.

  Moreover, you may comprise the communication part 6X of the case contact part 6B by both the said recessed part and the said through-hole. If this is the case, the circumference of the electrolyte solution can be further improved.

  Furthermore, in the said embodiment, although the recessed part as the communication part 6X was formed in the free end side of the case contact part 6B, it may be formed in the lower side part of the case contact part 6B.

  In addition, the shape of the recess may be a U-shape when viewed from the side, or may be a partial circle such as a semicircle, or a V-shape. It may be a thing, and may make a U-shape.

  In addition, the plurality of communication portions 6X formed in the case contact portion 6B have the same shape, but may have different shapes. Further, the shapes of the communication portions 6X formed on the plurality of case contact portions 6B may be different from each other, and the height positions of the communication portions 6X formed on the plurality of case contact portions 6B may be different from each other. good.

  In addition, the number of communication portions 6X is not limited to two, and may be one or three or more.

  In the above embodiment, the two opposite side surfaces of the electrode group are fixed to the battery case so as to be sandwiched between a pair of spacers. However, the two opposite side surfaces of the electrode group are sandwiched between three or more spacers. Alternatively, spacers may be provided between the four side surfaces of the electrode group and the inner peripheral surface of the battery case. Alternatively, each spacer may be integrated by a connecting portion.

  Further, the electrode group of the embodiment is arranged in the battery case so that the stacking direction is orthogonal to the central axis direction of the battery case, but the stacking direction is the same as the central axis direction of the battery case. It may be arranged so that

  Furthermore, an electrode group is not restricted to the structure of the said embodiment, It is good also considering at least one of a negative electrode plate or a positive electrode plate as a flat electrode plate.

  Moreover, although the current collection terminal of the negative electrode plate of the said embodiment was welded to the bottom face of a battery case, it may be welded to the inner peripheral surface of a battery case.

  In addition, the positive electrode plate and the negative electrode plate of the embodiment may be reversed. That is, you may comprise so that the current collection terminal of a positive electrode plate may be welded to the inner surface of a battery case.

  The present invention can be applied to secondary batteries such as lithium ion secondary batteries in addition to alkaline storage batteries, or may be applied to primary batteries.

  In addition, it goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 100 ... Cylindrical battery 2 ... Battery case C ... Center axis direction 2A of battery case ... Inner peripheral surface 3 of battery case ... Electrode group L ... Stacking direction 31 ... Positive electrode Plate 32 ... Negative electrode plate 33 ... Separator 6 ... Spacer 6a ... One surface (contact surface)
6b ... the other surface 6A ... electrode contact part 6B ... case contact part 6X ... communication part

Claims (5)

A cylindrical battery case;
An electrode group disposed in the battery case and composed of a positive electrode, a negative electrode, and a separator, and a pair of outer surfaces facing each other in a planar shape;
A spacer provided between the inner peripheral surface of the battery case and the outer surface forming the planar shape of the electrode group;
The spacer has a case contact portion that is continuously provided from one axial end portion to the other axial end portion and contacts the inner peripheral surface of the battery case,
In the case contact portion, a communication portion that communicates a space partitioned by the case contact portion is formed ,
A cylindrical battery in which a plurality of the communication portions are formed in the case contact portion along the axial direction . The communicating portion is cylindrical battery according to claim 1, wherein a recess formed in the free end side portion in contact with the inner peripheral surface of the battery case in the case contact part. The communicating portion is cylindrical battery according to claim 1 or 2 which is a through hole formed in the case contact part. The spacer has a plate-like electrode contact portion having a contact surface on one surface that contacts the outer surface of the electrode group,
The case contact part, any of the preceding claims wherein the other surface of the electrode contact portion to extend from one axial end portion of the electrode contact portion in the axial end portion is provided extending continuously 1-3 The cylindrical battery according to 1. The cylindrical battery according to claim 4 , wherein at least two of the case contact portions are formed in parallel along the central axis direction on the other surface of the electrode contact portion.