JP2017033900A - Lead-acid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress leakage of an electrolyte with liquid level rise.SOLUTION: A lead-acid battery 10 comprises an electrode group 30, an electrolyte W and a battery case 15 in which the electrode group 30 and the electrolyte W are accommodated. The battery case 15 includes at an upper side of the case: exhaust parts T, R, U, Q1 and Q2 by which a gas generated inside of the battery case 15 is taken in from a gas inlet and exhausted to the outside; a reflow part 85 which is provided separately from a gas inlet 81A of the exhaust parts T, R, U, Q1 and Q2 and causes droplets V within the exhaust parts T, R, U, Q1 and Q2 reflow into an accommodation space in which the electrolyte is accommodated, inside of the battery case 14; and a valve element 90 which prevents the electrolyte W from flowing from the accommodation space into the reflow part 85 by closing a flow passage L that is communicated from the reflow part 85 to the accommodation space, or the reflow part 85 in the case where a liquid level of the electrolyte W rises.SELECTED DRAWING: Figure 14

Description

  The present invention relates to a technique for suppressing leakage of an electrolytic solution accompanying a rise in liquid level.

  Lead storage batteries used for automobiles and the like have a structure in which gas generated in the battery case is exhausted in order to suppress an increase in the internal pressure of the battery. For example, in Patent Document 1 below, an exhaust cylinder and an exhaust chamber are provided between an inner lid and an upper lid that seal the battery case, and gas generated in the battery case is exhausted to the outside via the exhaust pipe and the exhaust chamber. It has a structure to do. In Patent Document 1 below, the bottom surface of the exhaust chamber is inclined to the reflux hole, so that the droplets in the exhaust chamber return to the battery case through the reflux hole.

Japanese Patent No. 5521390

Although the liquid droplets in the exhaust chamber (exhaust part) return to the inside of the battery case as described above, if the liquid level of the electrolyte contained in the battery case rises due to overcharging, the exhaust chamber (exhaust part) Liquid droplets may leak out from the outlet part of the part.
This invention is completed based on the above situations, Comprising: It aims at suppressing the leakage of the electrolyte solution accompanying a liquid level rise.

  The lead storage battery disclosed in the present specification includes an electrode group, an electrolytic solution, and a battery case that houses the electrode group and the electrolytic solution, and the battery case is disposed inside the battery case on an upper side of the case. An exhaust part that takes in the gas generated in the gas intake port and exhausts the gas to the outside, and the gas intake port of the exhaust part are provided separately, and droplets in the exhaust part are converted into the electrolysis in the battery case. A recirculation part that recirculates to a storage space that stores the liquid, and a flow path that connects the recirculation part to the storage space or the recirculation part when the liquid level of the electrolytic solution rises, so that the electrolytic solution is removed from the storage space. And a valve body that suppresses entry into the reflux portion. In addition, the interpretation of the meaning of “close” is determined based on whether or not an effect of suppressing the electrolyte from entering the reflux portion is generated, and the valve body “closes (without gaps) the flow path or the reflux portion. It does n’t matter if it ’s completely closed). That is, not only when the valve body seals the flow path or the reflux part, but when there is a gap between the closed valve body and the flow path or the reflux part, or a hole is formed in a part of the valve body. Even if it is not hermetically sealed, for example, it is included in “close” if the effect of suppressing the entry of the electrolyte into the reflux portion is produced.

  According to the lead storage battery disclosed in the present specification, it is possible to suppress the leakage of the electrolytic solution accompanying the rise in the liquid level.

The perspective view of the lead acid battery which concerns on Embodiment 1. Top view of the battery case Vertical sectional view of lead-acid battery (cross-sectional view taken along line AA in FIG. 1) Top view of the inner lid Bottom view of the inner lid Top view of the top lid Bottom view of top lid Fig. 4 is a partially enlarged view (showing the gas exhaust passage) FIG. 7 is an enlarged view (showing the gas exhaust passage) Sectional drawing which shows the structure of an exhaust pipe (BB sectional view taken on the line in FIG. 8) Sectional view showing the structure of the exhaust passage Fig. 8 is an enlarged view of part of Fig. 8 (showing the reflux path of the droplet) The figure which expanded the C section of FIG. Sectional view of lower exhaust cylinder and cylinder (cross-sectional view along line DD in FIG. 13) Cross-sectional view of lower exhaust cylinder and cylinder (shows comparative example) Sectional drawing which shows the opening-closing structure of a reflux hole in the lead acid battery which concerns on Embodiment 2. Bottom view of bottom lid Sectional drawing of the liquid spigot which shows other embodiment

  The lead storage battery disclosed in the present specification includes an electrode group, an electrolytic solution, and a battery case that houses the electrode group and the electrolytic solution, and the battery case is disposed inside the battery case on an upper side of the case. An exhaust part that takes in the gas generated in the gas intake port and exhausts the gas to the outside, and the gas intake port of the exhaust part are provided separately, and droplets in the exhaust part are converted into the electrolysis in the battery case. A recirculation part that recirculates to a storage space that stores the liquid, and a flow path that connects the recirculation part to the storage space or the recirculation part when the liquid level of the electrolytic solution rises, so that the electrolytic solution is removed from the storage space. And a valve body that suppresses entry into the reflux portion.

  When the liquid level of the electrolytic solution rises due to overcharging, the liquid droplets in the exhaust unit return to the storage space containing the electrolytic solution from the reflux unit. An attempt was made to identify the cause of the leakage of liquid droplets from the outside. Then, the inventors observe the intrusion path of the electrolyte to the exhaust part, and when the liquid level rises and approaches the reflux part, the gas generated in the battery case is discharged from the reflux part for refluxing the droplets to the exhaust part. It was determined that the phenomenon of flowing to the side became prominent, and it was specified that the electrolyte entered the exhaust part together with the gas.

  As described above, the present inventors have come up with the idea of providing a valve body that closes the flow path or the reflux part that leads from the reflux part to the accommodating space for accommodating the electrolytic solution when the liquid level rises. In this configuration, when the liquid level rises, it is possible to suppress the electrolyte from entering the exhaust part from the reflux part. Therefore, it is possible to reduce the electrolyte solution that enters the exhaust portion, and it is possible to suppress the electrolyte solution from leaking from the exhaust portion to the outside. Moreover, since the reflux part is provided separately from the gas intake port on the exhaust part side, the gas exhaust function can be maintained even if the reflux part is closed by the valve body.

  Further, as one embodiment of the lead storage battery disclosed in the present specification, the valve body closes the flow path or the reflux portion by utilizing a rise in the electrolyte level in the battery case, and The flow path or the reflux portion is opened using the liquid level drop. In this configuration, when the liquid level is lowered, the electrolytic solution in the exhaust part is refluxed to the battery case, and when the liquid level is raised, the electrolytic solution in the battery case can be prevented from entering the exhaust part from the reflux part. Further, since the valve body is opened and closed by utilizing the liquid level displacement of the electrolytic solution, a mechanism for opening and closing the valve body is unnecessary.

  As one embodiment of the lead storage battery disclosed in the present specification, the valve body closes the flow path at a position away from the reflux portion. In this configuration, since the flow path is closed at a position away from the reflux part, the effect of suppressing the electrolyte from entering the exhaust part through the reflux part is high.

  Further, as one embodiment of the lead storage battery disclosed in the present specification, the battery case extends downward from the upper surface wall of the battery case so as to surround the reflux portion, and forms a flow path therein. The valve body opens and closes the flow path formed in the cylindrical body by utilizing the displacement of the liquid surface of the electrolytic solution. In this configuration, the reflux portion is surrounded by a cylinder. Therefore, for example, when the liquid level is lowered, it is possible to suppress the splash of the electrolytic solution due to vibration or the like from entering the exhaust part through the reflux part. Further, since the valve body is closed when the liquid level rises, it is possible to suppress the electrolyte or gas from entering the flow path formed in the cylindrical body. Therefore, the effect of suppressing the entry of the electrolytic solution is high.

  Moreover, as one Embodiment of the lead acid battery disclosed by this specification, the said valve body is connected with the said cylinder via the hinge, and opens and closes the said flow path formed in the said cylinder. In this configuration, since the valve body is connected to the cylinder body by a hinge, the relative positional relationship between the flow path and the valve body is difficult to shift during opening and closing. Therefore, since the sealing property when the valve body is closed is high, the effect of suppressing the entry of the electrolytic solution is high. In addition, since the valve body is opened and closed by rotation about the hinge, there is also an advantage that it can be opened and closed smoothly.

  Further, as one embodiment of the lead storage battery disclosed in the present specification, the valve body is formed integrally with the cylindrical body. In this configuration, the number of parts can be reduced as compared with the case where the valve body is separated.

  Moreover, as one embodiment of the lead storage battery disclosed in the present specification, the valve body is a float that opens and closes the flow path or the reflux portion using displacement of the liquid surface of the electrolytic solution. Since this configuration is simple and excellent in durability, valve opening / closing failure hardly occurs.

  Further, as one embodiment of the lead-acid battery disclosed in the present specification, the battery case has a cylindrical body that extends downward from an upper surface wall of the battery case, and surrounds the reflux portion. It arrange | positions inside the said cylinder. In this configuration, the reflux portion is surrounded by a cylinder. Therefore, for example, when the liquid level is lowered, it is possible to prevent the splash of the electrolytic solution due to vibration or the like from entering the exhaust part through the reflux part. And since the float is arrange | positioned inside the cylinder, the position of a float can be positioned substantially under the return part.

  Further, as one embodiment of the lead storage battery disclosed in the present specification, the battery case has an upper surface that is open and accommodates the electrode group and the electrolyte solution; a lid member that seals the battery case; The lid member includes the exhaust part, the reflux part, and the valve body. In this configuration, an exhaust part and a reflux part are provided on the lid member that seals the battery case. Therefore, the gas generated in the battery case can be exhausted to the outside through the exhaust part of the lid member, and the droplets in the exhaust part can be refluxed into the battery case through the reflux part. Moreover, since the lid member includes a valve body that closes the flow path or the reflux part that connects the reflux part to the battery case when the liquid level rises, the electrolyte solution enters the exhaust part from the reflux part when the liquid level rises. Can be suppressed. Therefore, it is possible to reduce the electrolyte solution which enters the exhaust part, and it is possible to suppress the electrolyte solution from leaking from the exhaust part to the outside.

<Embodiment 1>
A first embodiment will be described with reference to FIGS.
1. Structure of the lead storage battery 10 The lead storage battery 10 is for vehicles such as automobiles, specifically for idling stop vehicles, and is installed, for example, in the engine room or luggage space of the vehicle and supplies power to the vehicle. The lead storage battery 10 is a liquid lead storage battery, and includes a battery case 15, an electrode plate group 30, an electrolyte solution W, and terminal portions 40P and 40N as shown in FIGS. In the following description, the horizontal direction of the battery case 15 (the arrangement direction of the terminal portions 40P and 40N) when the battery case 15 is placed horizontally without being inclined with respect to the installation surface is defined as the X direction. The height direction (vertical direction) is the Y direction, and the depth direction is the Z direction.

  The battery case 15 includes a battery case 20 that houses the electrode plate group 30 and the electrolytic solution W, and a lid member 50. The battery case 20 is made of synthetic resin. The battery case 20 includes four outer walls 21 and a bottom wall 22 and has a box shape with an open top surface. As shown in FIG. 2, the battery case 20 has a plurality of (five in this example) partition walls 23. The partition walls 23 are formed at approximately equal intervals in the X direction, and partition the inside of the battery case into a plurality of cell chambers 25. Six cell chambers 25 are provided in the width direction of the battery case 20 (X direction in FIG. 2), and each cell chamber 25 accommodates an electrode plate group 30 together with an electrolyte W made of dilute sulfuric acid. .

  As shown in FIG. 3, the electrode plate group 30 includes a positive electrode plate 30P, a negative electrode plate 30N, and a separator 30C that partitions the electrode plates 30P and 30N. Each of the electrode plates 30P and 30N is configured by filling a lattice with an active material, and ears 31P and 31N are provided at the upper part. The ears 31 </ b> P and 31 </ b> N are provided to connect the electrode plates 30 </ b> P and 30 </ b> N having the same polarity through the strap 32 in the cell chamber 25. The main component of the active material of the positive electrode plate 30P is lead dioxide, and the main component of the active material of the negative electrode plate 30N is lead.

  The strap 32 is, for example, a plate shape long in the X direction, and one set for a positive electrode and a negative electrode is provided for each cell chamber 25. Then, the positive and negative straps 32 of the adjacent cell chambers 25 are electrically connected to each other via a connection portion 33 formed on the strap 32 to connect the electrode plate groups 30 of the cell chambers 25 in series. It has a structure.

  The lid member 50 includes an inner lid 60 and an upper lid 100. 4 is a plan view of the inner lid 60 as viewed from above with the upper lid 100 removed, and FIG. 5 is a bottom view of the inner lid 60 as viewed from below. The inner lid 60 is made of a synthetic resin and includes a lid main body 61 and a flange portion 67. The inner lid 60 is an example of the “upper surface of the battery case” in the present invention.

  The lid body 61 of the inner lid 60 has a size that can seal the upper surface of the battery case 20. The lid body 61 has a plurality of inner walls 91 and a plurality of partition walls 93 on the lower surface. The inner wall 91 is located inside the flange portion 67 and protrudes downward from the lower surface of the lid main body 61. Each inner wall 91 is provided corresponding to the four outer walls 21 constituting the battery case 20 and has a frame shape as a whole. Each partition wall 93 protrudes downward from the lower surface of the lid body 61, similarly to the inner wall 91. Each partition wall 93 is provided corresponding to each partition wall 23 of the battery case 20, and is formed so as to connect two inner walls 91 facing in the Z direction.

  Each inner wall 91 of the inner lid 60 overlaps with the upper end surface of each outer wall 21 of the battery case 20, and each partition wall 93 of the inner lid 60 overlaps with the upper end surface of each partition wall 23 of the battery case 20. In this manner, the battery case 20 and each cell chamber 25 are hermetically sealed by overlapping the inner wall 91 and the partition wall 93 on the inner lid 60 side with the respective walls 21 and 23 on the battery case 20 side. In addition, the inner wall 91 and the outer wall 21, and the partition wall 93 and the partition wall 23 are joined by heat welding so that airtightness is maintained. The flange portion 67 is formed on the outer peripheral edge of the lid body 61. The flange portion 67 extends downward from the back surface of the lid body 61 and surrounds the upper portion of the outer wall 21 of the battery case 20.

  As shown in FIGS. 1 and 4, the lid body 61 of the inner lid 60 has a low surface portion 62, a high surface portion 64, and a platform portion 65, and has a shape with a difference in height. Yes. The low surface portion 62 is provided on the rear side and the front side of the lid member 50. Positive and negative terminal portions 40P and 40N are disposed on the respective low surface portions 62 provided at both corners in the X direction on the front side.

  Since the structures of the positive terminal portion 40P and the negative terminal portion 40N are the same, the structure will be described below taking the negative terminal portion 40N as an example. As shown in FIG. 3, the negative terminal portion 40 </ b> N includes a bushing 41 and a pole column 45. The bushing 41 is made of a metal such as a lead alloy and has a hollow cylindrical shape. As shown in FIG. 3, the bushing 41 passes through a cylindrical mounting portion 63 formed integrally with the inner lid 60, and the upper half protrudes from the upper surface of the lower surface portion 62. The upper half part exposed from the upper surface of the low surface part 62 among the bushing 41 is a terminal connection part, and connection terminals (not shown), such as a harness terminal, are assembled | attached.

  In addition, since the inner lid 60 is integrally formed by pouring resin into a mold in which the bushing 41 is inserted, the mounting portion 63 is integrated with the bushing 41 and covers the lower outer periphery of the bushing 41 without a gap. That is, the bushing 41 has a structure in which the other part except the upper half protruding from the upper surface of the inner lid 60 is embedded in the mounting portion 63 of the inner lid 60.

  The pole column 45 is made of a metal such as a lead alloy and has a cylindrical shape. The pole 45 is located inside the bushing 41. The pole column 45 is longer than the bushing 41, the upper portion of the pole column 45 is located inside the bushing 41, and the lower portion projects downward from the lower surface of the bushing 41. The upper end portion of the pole column 45 is joined to the bushing 41 by welding, and the base end portion 47 of the pole column 45 is joined to the strap 32 of the electrode plate group 30.

  The high surface portion 64 of the inner lid 60 is formed at the front center of the lid body 61. The high surface portion 64 is located between the low surface portions 62 formed at both corners in the X direction. The upper surface of the high surface portion 64 is higher than the upper surfaces of the terminal portions 40P and 40N. By doing so, even if a metal member or the like is placed on the upper part of the battery, it is difficult to contact the terminal portions 40P and 40N at the same time, and conduction can be prevented.

  The platform 65 is formed on the rear side of the lid main body 61. The platform 65 extends in the X direction so as to cross the six cell chambers 25 provided in the battery case 20. The upper surface of the trapezoidal portion 65 is higher than the low surface portion 62 and lower than the high surface portion 64.

  As shown in FIG. 4, the base portion 65 of the inner lid 60 has six liquid injection holes 75 in the X direction. These six liquid injection holes 75 penetrate the base portion 65 in the vertical direction and communicate with the six cell chambers 25, respectively. Therefore, it is possible to inject the electrolyte W from each injection hole 75 into each cell chamber 25 of the battery case 20.

  Moreover, the base-shaped part 65 has the lower partition 71-73 which protruded upwards. The lower partition walls 71 to 73 are provided corresponding to the respective liquid injection holes 75 and have a rectangular frame shape surrounding each liquid injection hole 75. Each lower partition 72 is provided on the same straight line extending in the X direction.

  The upper lid 100 is made of a synthetic resin like the inner lid 60. FIG. 6 is a plan view of the upper lid 100 as viewed from above, and FIG. 7 is a bottom view of the upper lid 100 as viewed from below. The upper lid 100 includes a lid main body 110 and a flange portion 105. The lid body 110 has a rectangular shape that follows the platform portion 65 of the inner lid 60, and is attached to the platform portion 65 of the middle lid 60 in an overlapping manner. The flange portion 105 is formed on the outer peripheral edge of the lid main body 110. The flange portion 105 extends downward from the outer peripheral edge of the lid main body 110 and surrounds the outer periphery of the base portion 65.

  Further, as shown in FIG. 7, the lid body 110 has upper partition walls 121 to 123. The upper partition walls 121 to 123 protrude downward from the lower surface of the lid main body 110 and are provided for each liquid injection hole 75. The upper partition walls 121 to 123 have a rectangular frame shape like the lower partition walls 71 to 73. Each upper partition 122 is provided on the same straight line extending in the X direction.

  Each upper partition 121-123 corresponds to each lower partition 71-73, and each upper partition 121-123 is arranged so as to overlap the upper side of each lower partition 71-73. The upper partition walls 121 to 123 and the lower partition walls 71 to 73 constitute partition walls that surround the liquid injection holes 75. The upper partition walls 121 to 123 and the lower partition walls 71 to 73 are joined to each other by thermal welding.

  The lid member 50 of the lead storage battery 10 includes an exhaust tube T, an exhaust passage R, a common passage U, and collective exhaust portions Q1 and Q2 between the inner lid 60 and the upper lid 100. In the following, description will be made with reference to the drawings. The “exhaust tube T”, “exhaust passage R”, “common passage U”, and “collective exhaust portions Q1, Q2” are examples of the “exhaust portion” of the present invention.

(Description of exhaust tube T)
The exhaust tube T is divided into a lower exhaust tube 81 and an upper exhaust tube 131. As shown in FIG. 4, the lower exhaust cylinder 81 corresponds to each cell chamber 25 of the battery case 20 and is provided in the X direction with respect to the inner lid 60. Each of the lower exhaust cylinders 81 is a rectangular cylinder with a hollow inside, and extends in both the up and down directions (Y direction) while penetrating the inner lid 60. The bottom surface portion 81 </ b> A and the slit 83 of the lower exhaust cylinder 81 are gas intake ports that take in the gas generated in the cell chamber 25.

  As shown in FIG. 7, the upper exhaust pipe 131 corresponds to each cell chamber 25 of the battery case 20, and six upper exhaust pipes 131 are provided in the X direction with respect to the upper lid 100. The upper exhaust tube 131 is a rectangular tube type whose upper surface is closed, and protrudes downward from the lower surface of the lid body 110.

  Each upper exhaust cylinder 131 and each lower exhaust cylinder 81 overlap each other to constitute an exhaust cylinder T as shown in FIG. Each exhaust tube T communicates with the cell chamber 25 of the battery case 20, and communicates with each exhaust passage R through a notch 132 formed in the upper exhaust tube 131. Therefore, the gas generated in each cell chamber 25 of the battery case 20 can flow through the notch 132 to the exhaust passage R after passing through the inside of the lower exhaust cylinder 81. Note that the end surfaces of the lower exhaust cylinders 81 and the upper exhaust cylinders 131 are joined to each other by thermal welding so that the air tightness of the exhaust cylinder T is ensured.

  Note that, as shown in FIG. 10, the upper end portion of the lower exhaust cylinder 81 communicating with the exhaust passage R is at a position higher than the reflux hole 85, and the liquid level that has risen due to overcharge is higher than the reflux hole 85. Even when the height is reached, the relationship protrudes from the liquid level. Similarly, the upper end position of the slit 83 is also higher than the reflux hole 85, and even if the liquid level that has risen due to overcharge reaches the height of the reflux hole 85, it projects from the liquid level. It has become.

  In addition, two protrusions 82A and 82B are provided on the inner wall of the lower exhaust cylinder 81. The two protrusions 82A and 82B face the X direction while shifting their positions in the vertical direction (Y direction). By providing these protrusions 82A and 82B on the inner wall of the lower exhaust cylinder 81, the electrolyte W splashed from the cell chamber 25 is discharged into the exhaust passage R while securing a path for exhausting the gas generated from the cell chamber 25. It is possible to realize a route that is difficult to enter.

  Further, a slit 83 is provided in a lower part of the wall of the lower exhaust cylinder 81. The slit 83 functions to allow the electrolyte W to escape outside the cylinder so that the electrolyte W does not rise inside the lower exhaust cylinder 81 and flow into the exhaust passage R when the liquid level rises due to overcharging.

(Description of exhaust passage R)
The exhaust passage R is a gas exhaust space, and is provided for each cell chamber 25 of the battery case 20 between the inner lid 60 and the upper lid 100. As shown in FIGS. 4 and 7, each exhaust passage R communicates with the common passage U, and fulfills the function of circulating the gas flowing out from the exhaust tube T to the common passage U.

  Hereinafter, the configuration of the exhaust passage R will be specifically described. As shown in FIG. 8, the platform portion 65 of the inner lid 60 has a plurality of lower passage walls 84 for each cell chamber 25 of the battery case 20. The plurality of lower passage walls 84 protrude upward from the base portion 65. The upper end surfaces of these lower passage walls 84 have the same height.

  On the other hand, the lid body 110 of the upper lid 100 has a plurality of upper passage walls 134 for each cell chamber 25 of the battery case 20, as shown in FIG. The plurality of upper passage walls 134 protrude downward from the lower surface of the lid body 110. The lower end surfaces of these upper passage walls 134 have the same height.

  Each upper passage wall 134 corresponds to each lower passage wall 84 and overlaps the upper side of the corresponding lower passage wall 84. As shown in FIG. 11, the lower passage wall 84 and the upper passage wall 134 constitute a passage wall RW, and the exhaust passage R is provided between a pair of opposing passage walls RW as side walls. The lower passage wall 84 and the upper passage wall 134 are joined to each other by thermal welding so that the air tightness of the exhaust passage R is ensured.

  The exhaust passage R is as shown in FIG. 8 and FIG. 9, with the notch 132 of the upper exhaust tube 131 as the inlet, while meandering left and right (in FIG. 8 and FIG. 9). Proceed to the upper side) and reach the common passage U.

(Description of common passage U, collective exhaust parts Q1, Q2)
As shown in FIGS. 8 and 9, the common passage U is formed between the lower partition wall 72 and the lower passage wall 84A and between the upper partition wall 122 and the upper passage wall 134A. That is, the common passage U is provided between the upper partition wall 122 and the lower partition wall 72, the upper passage wall 134A and the lower passage wall 84A as two side walls. The common passage U extends in the X direction so as to cross each exhaust passage R. Collective exhaust portions Q1 and Q2 are provided at both ends in the X direction corresponding to the end of the common passage U.

  The collective exhaust parts Q1 and Q2 are provided between the inner lid 60 and the upper lid 100, and the lower cylindrical part Q1 provided on the platform 65 of the inner lid 60 and the upper cylindrical part provided on the upper lid 100. Q2 (see FIGS. 8 and 9). The lower cylindrical portion Q1 protrudes upward from the base portion 65. The lower cylinder portion Q1 is formed with an opening and communicates with the common passage U.

  The upper cylinder portion Q2 protrudes downward from the lower surface of the upper lid 100. The upper cylinder part Q2 overlaps the lower cylinder part Q1. The lower cylindrical portion Q1 and the upper cylindrical portion Q2 are joined to each other by heat welding so that airtightness is ensured.

  In addition, as shown in FIG. 9, the porous filter 150 is accommodated in the upper cylinder part Q2. The lower surface of the porous filter 150 is located above the tip surface of the upper cylindrical portion Q2. The porous filter 150 suppresses the release of water vapor and acid mist and suppresses the entry of external sparks.

  The upper lid 100 is provided with a cylindrical exhaust duct 160. One end of the exhaust duct 160 is connected (communication) to the upper cylindrical portion Q2, and the other end passes through the flange portion 105 of the upper lid 100 and opens to the outside. Therefore, the gas sent from the common passage U to the collective exhaust portions Q1 and Q2 can be exhausted to the outside through the exhaust duct 160.

  That is, in the lead storage battery 10, the gas generated in each cell chamber 25 of the battery case 20 first flows from each lower exhaust cylinder 81 to each exhaust passage R. Thereafter, the gas flows through the common passage U into the collective exhaust part Q and is finally exhausted from the exhaust duct 160 to the outside.

  Note that either one of the collective exhaust portions Q1 and Q2 is opened according to the use environment, and the other is sealed with a plug (not shown). In this example, after passing through the common passage U, the gas passing through the exhaust passage R is exhausted to the outside through the collective exhaust portions Q1 and Q2 on the right side (right side in FIG. 4 and left side in FIG. 7) when viewed from the front in the Z direction. The In FIG. 8, the arrows are illustrated on the assumption that the left collective exhaust part Q1 as viewed from the front in the Z direction is opened without being sealed.

2. The reflux structure of the droplet V and the closed structure of the flow path L connected to the cell chamber 35 from the reflux hole 85 The inner lid 60 has six reflux holes 85 in the X direction corresponding to each cell chamber 25 of the battery case 20. have. Each reflux hole 85 passes through the base portion 65 of the inner lid 60 and communicates with the cell chamber 25 of the battery case 20. As shown in FIG. 8, the reflux hole 85 is disposed at the inlet portion of the exhaust passage R and is located farthest from the exhaust passage R when viewed from the common passage U.

  In addition, the trapezoidal portion 65 which is the bottom surface of the exhaust passage R is inclined (gradient) so as to become lower as it is closer to the reflux hole 85 (see FIGS. 3 and 10). Therefore, the droplet V in the exhaust passage R can be returned to each cell chamber 25 through the return hole 85.

  That is, the water vapor contained in the gas generated in the cell chamber 25 is condensed in the exhaust passage R when the gas passes through the exhaust passage R. The condensed droplet V flows toward the reflux hole 85 as shown by a one-dot chain line arrow in FIG. Therefore, the droplets V such as water vapor contained in the gas can be refluxed to each cell chamber 25.

  Further, as shown in FIGS. 5 and 13, the inner lid 60 has a cylindrical body 87 corresponding to each reflux hole 85. As shown in FIG. 14, the cylindrical body 87 extends downward from the base portion 65 of the inner lid 60. The cylindrical body 87 is a rectangular cylindrical shape having an open bottom and surrounds the reflux hole 85. The cylinder 87 is aligned with the lower exhaust cylinder 81 in the X direction, and shares a part of the wall. The inside of the cylindrical body 87 is a flow path L connected from the reflux hole 85 to the cell chamber 25, and the droplet V that is refluxed from the reflux hole 85 passes through the flow path L in the cylinder and enters the cell chamber 25. Return to. Further, the cylindrical body 87 functions to suppress the electrolytic solution splashed from the cell chamber 25 from entering the exhaust passage R through the reflux hole 85 when vibration is applied, for example, when the vehicle is running. The “reflux hole 85” is an example of the “reflux part” in the present invention, and the cylindrical body 87 is not included in the “reflux part”. The “internal space of the cell chamber 25” is an example of the “accommodating space for accommodating the electrolytic solution” of the present invention.

  Further, as shown in FIGS. 13 and 14, the cylindrical body 87 is provided with a bottom cover 90. The bottom lid 90 is sized to close the bottom surface of the cylinder 87 corresponding to the outlet of the flow path L, and is connected to the lower end of the cylinder 87 via a hinge 89. The bottom cover 90 is rotatable about the hinge 89. When the liquid level of the electrolytic solution W is lower than the bottom surface of the cylindrical body 87, the bottom cover 90 is inclined by its own weight, and as shown in FIG. The bottom surface of the cylindrical body 87 corresponding to the outlet of is opened. On the other hand, when the liquid level of the electrolytic solution W rises, the bottom surface of the cylindrical body 87 corresponding to the outlet of the flow path L is closed as shown in FIG. As described above, the bottom cover 90 functions as a valve body that closes the flow path L connected from the reflux hole 85 to the cell chamber 25 when the liquid level rises. In this example, the hinge 89 and the bottom lid 90 are formed integrally with the middle lid 60, and the middle lid 60 is a single part including the cylindrical body 87, the hinge 89, and the bottom lid 90. Yes. The bottom cover 90 is an example of the “valve element” in the present invention.

  By providing the bottom lid 90, the following effects can be obtained. Usually, the gas generated in the cell chamber 25 of the battery case 20 flows into the exhaust passage R between the lids 60 and 100 through the lower exhaust cylinder 81, and then the common passage U and the collective exhaust portions Q1 and Q2. The air is exhausted from the exhaust duct 160 to the outside.

  However, as shown in FIG. 15, when the liquid level that has risen due to overcharging closes the bottom surface of the cylindrical body 87, the gas generated in the cell chamber 25 of the battery case 20 is not only returned to the lower exhaust cylinder 81, but also recirculated. The state of flowing into the exhaust passage R through the hole 85 becomes noticeable. This is because the gas in the cylinder 87 cannot escape outside the cylinder. When the state in which the gas flows into the exhaust path R from the reflux hole 85 becomes significant, a phenomenon in which the electrolyte W enters the exhaust path R from the reflux hole 85 together with the gas passing through the reflux hole 85 occurs.

  On the other hand, since gas also flows into the exhaust passage R from the adjacent lower exhaust cylinder 81, a part of the electrolyte W entering from the reflux hole 85 moves to the outlet side of the exhaust passage R by the gas flow. To do. Such a phenomenon becomes conspicuous as the distance from the reflux hole 85 to the electrolytic solution W becomes shorter due to the rise of the electrolytic solution W, so that a lot of the electrolytic solution W enters the exhaust path R, and a part of the phenomenon. There is a possibility of leakage from the exhaust duct 160.

  Further, when the liquid level of the electrolyte W further rises from the height of the bottom surface of the cylindrical body 87, the increased liquid level blocks the gas flow and is a space closed around the exhaust cylinder 81 and the cylindrical body 87 (for example, A symbol “K” in FIG. 15 is created. In the closed space, the internal pressure rises due to the rise of the liquid level, so that an internal pressure difference is generated between the cylinder 87 and the liquid level easily rises inside the cylinder 87. Therefore, since the electrolyte W easily enters the exhaust path R from the reflux hole 85, the possibility that a part of the electrolyte W leaks from the exhaust duct 160 is further increased.

  The lead storage battery 10 of this embodiment is provided with a bottom lid 90 that functions as a valve body with respect to the cylinder 87 of the inner lid 60, and the rising liquid level is a cylinder as shown in FIG. When the bottom surface of 87 is reached, the bottom cover 90 closes the bottom surface of the cylinder 87. That is, the outlet of the flow path L connected to the cell chamber 25 from the reflux hole 85 is closed. Therefore, even if the liquid level that has risen due to overcharge reaches the height of the bottom surface of the cylinder 87, the gas generated in the cell chamber 25 of the battery case 20 flows into the exhaust passage R from the lower exhaust cylinder 81. The amount of gas passing through the reflux hole 85 can be suppressed.

  Therefore, the extent to which the electrolyte W in the cell chamber 25 enters the exhaust passage R from the reflux hole 85 can be suppressed. Accordingly, since the electrolyte W entering the exhaust passage R can be reduced, it is possible to suppress the electrolyte W from leaking from the exhaust duct 160 to the outside. Even when the cylinder 87 is closed, the gas in the cell chamber 25 can be taken into the lower exhaust part 81 through the bottom part 81 </ b> A and the slit 83. Therefore, since the gas in the cell chamber 25 can be exhausted from the lower exhaust cylinder 81 via the exhaust path R, the gas exhaust performance is not impaired.

  When the liquid level of the electrolytic solution W falls below the bottom surface of the cylindrical body 87, the bottom lid 90 is inclined by its own weight and opens the bottom surface of the cylindrical body 87, as shown in FIG. Thereby, the flow path L connected from the reflux hole 85 into the cell chamber 25 is opened. Therefore, after the bottom surface is opened, the droplet V in the exhaust passage R can be refluxed into the cell chamber 25 through the reflux hole 85 and the cylinder 87. In addition, when the liquid level rise by overcharge etc. has not arisen, as shown to (a) of FIG. 14, a liquid level exists under the bottom cover 90, and the bottom cover 90 maintains the open state.

  The bottom cover 90 preferably closes the bottom surface of the cylindrical body 87 (completely closes without a gap). However, if the bottom lid 90 has an effect of suppressing the entry of the electrolyte when closed, the bottom cover 90 is not necessarily sealed. You don't have to. For example, when it is closed, there may be a gap between the bottom surface of the cylinder 87 or a hole may be formed in a part of the lid.

3. Explanation of Effects As described above, when the liquid level rises, the bottom cover 90 closes the bottom surface of the cylindrical body 87, thereby closing the flow path L connected from the reflux hole 85 to the cell chamber 25. Therefore, it is possible to suppress the electrolyte W from entering the exhaust passage R from the cell chamber 25 through the reflux hole 85. Therefore, the electrolytic solution W is difficult to leak to the outside.

  In addition, since the bottom cover 90 is opened and closed by using the displacement (height change) of the electrolyte solution W, a mechanism for opening and closing the bottom cover 90 is unnecessary.

  Further, the bottom cover 90 closes the flow path L at a position away from the reflux hole 85. Specifically, as shown in FIG. 14 (b), the bottom cover 90 closes the bottom surface of the cylindrical body 87 corresponding to the outlet of the flow path L at a distance H from the reflux hole 85. In this configuration, since the flow path L is closed at a position away from the reflux hole 85, the effect of suppressing the electrolyte from entering the exhaust passage R side through the reflux hole 85 is high.

  Further, since the bottom cover 90 is connected to the cylindrical body 87 by a hinge 89, the relative positional relationship between the bottom cover 90 and the bottom surface of the cylindrical body 87 is difficult to shift during opening and closing. Therefore, since the airtightness when the bottom lid 90 is closed is high, the effect of suppressing the entry of the electrolytic solution W is high. Further, since the bottom cover 90 is opened and closed by rotation about the hinge 89, there is also an advantage that the opening and closing can be performed smoothly. Further, since the bottom cover 90 is formed integrally with the cylindrical body 87, there is no increase in the number of parts compared to the case where the bottom cover 90 is constituted by another part.

  Further, since the periphery of the reflux hole 85 is surrounded by the cylindrical body 87, for example, when the liquid level is lowered, the splash of the electrolytic solution due to vibration or the like enters the exhaust passage R from the cell chamber 25 through the reflux hole 85. It can be suppressed. Therefore, not only when the liquid level rises but also when the liquid level falls, the electrolytic solution W hardly leaks to the outside.

  Further, the lead storage battery 10 for an idling stop vehicle has a large number of electrode plates for design reasons and a narrow space between the electrode plates. Therefore, gas easily accumulates between the electrode plates, so that the liquid level is likely to rise, and the phenomenon of the electrolyte W entering through the reflux hole 85 is more likely to occur than in a conventional lead-acid battery for an engine vehicle. Therefore, by providing the bottom lid 90 that closes the bottom surface of the cylinder 87, the problem of the electrolyte solution W leaking to the outside in the lead storage battery 10 for the idling stop vehicle can be remarkably improved.

<Embodiment 2>
Next, a second embodiment of the present invention will be described with reference to FIGS.
The first embodiment exemplifies a structure in which the flow path L connected from the reflux hole 85 to the cell chamber 25 is closed by closing the bottom surface of the cylinder 87 with the bottom cover 90 when the liquid level rises. In the second embodiment, the reflux hole 85 is closed using the float 200. More specifically, the float 200 is accommodated in a cylindrical body 87 as shown in FIG. The float 200 is, for example, a sphere made of synthetic resin (eg, “PP” or “PP / PE”), and has a specific gravity smaller than that of the electrolytic solution W. A bottom lid 210 is attached to the bottom surface of the cylinder 87. The bottom lid 210 is sized to close the bottom surface of the cylindrical body 87, and as shown in FIG. 17, a circular opening 213 having radial slits 214 is provided at the center. “PP” is polypropylene and “PP / PE” is polypropylene / polyethylene.

  As shown in FIG. 16A, when the level of the electrolytic solution W is lower than the bottom surface of the cylinder 87, the float 200 rides on the opening 213 of the bottom lid 210, and the reflux hole 85 opens. Become. Accordingly, the droplet V in the exhaust passage R is recirculated into the cylinder 87 from the recirculation hole 85. Since the radial slit 214 is formed in the opening 213 of the bottom lid 210, the droplet V that has refluxed through the reflux hole 85 is returned to the cell chamber 25 through the slit 214 without remaining in the cylinder 87.

  On the other hand, when the liquid level of the electrolytic solution W rises, the float 200 in the cylindrical body 87 is lifted by the liquid level, and the reflux hole 85 is closed as shown in FIG. Therefore, as in the case of the first embodiment, since the electrolyte solution W can be prevented from entering the exhaust passage R through the reflux hole 85, the electrolyte solution W is difficult to leak to the outside. Further, when the liquid level is lowered, the state returns to the state of FIG. 16A and the reflux hole 85 is opened. Therefore, after the liquid level is lowered, the droplet V in the exhaust passage R can be returned to the cell chamber 25 via the reflux hole 85 and the cylindrical body 87 as described above.

  As described above, the second embodiment can also prevent the electrolytic solution W from entering the exhaust passage R from the cell chamber 25 through the reflux hole 85 when the liquid level rises, as in the first embodiment. It becomes difficult to leak outside. In the second embodiment, the reflux hole 85 is opened and closed using the float 200. If it is the float 200, since it is a simple structure and is excellent in durability, it is hard to generate | occur | produce the opening-and-closing defect of the reflux hole 85. FIG. Further, the float 200 is disposed inside the cylindrical body 87. Therefore, the position of the float 200 can be generally positioned below the reflux hole 85.

  The float 200 preferably seals the reflux hole 85 (completely closed without a gap). However, if the effect of suppressing the entry of the electrolytic solution is produced when the float 200 is closed, the reflux hole 85 is not necessarily sealed. It does not have to be. For example, there may be a partial gap between the reflux hole 85.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.

  (1) In the first embodiment, as an example of the “valve element”, the bottom cover 90 that opens and closes the flow path L connected to the cell chamber 25 from the reflux hole 85 is illustrated using the displacement of the liquid level. In the second embodiment, the float 200 that opens and closes the reflux hole 85 using the displacement of the liquid level is exemplified. The “valve element” only needs to be able to close the reflux hole 85 or the flow path L when the liquid level of the electrolytic solution W rises, and does not necessarily have to be a mechanism that operates using displacement of the liquid level. For example, when the liquid level of the electrolytic solution W is detected by a sensor or the like and the liquid level rises to a predetermined height, the “valve element” is operated in response to the output from the sensor, whereby the reflux hole 85 or the flow path L may be closed.

  (2) In the first embodiment, the structure of opening and closing the outlet of the flow path L connected to the cell chamber 25 from the reflux hole 85 using the bottom lid 90 is illustrated. Also good. Further, the reflux hole 85 may be directly opened and closed with a lid-like valve body. Moreover, in Embodiment 2, the structure which opens and closes the reflux hole 85 using the float 200 was illustrated, but you may make it open and close the flow path L using the float 200.

  (3) In the first and second embodiments, the example in which the lid member 50 includes the inner lid 60 and the upper lid 100 has been described. The inner lid 60 and the upper lid 100 do not necessarily have to be separate bodies, and may be a lid having a structure in which the inner lid 60 and the upper lid 100 are integrated.

  (4) In Embodiments 1 and 2, the lead storage battery has a structure in which the lid member 50 has a double lid structure of the inner lid 60 and the upper lid 100, and the exhaust path R, the common passage U, and the collective exhaust portions Q1 and Q2 are provided between the lids. For example, the present invention can be applied to a lead storage battery having a structure in which the gas generated in the battery case 20 is exhausted to the outside through the inside of the liquid port plug 310.

  FIG. 18 is a cross-sectional view of the liquid spigot 310. The liquid spigot 310 has a cylindrical shape with an open bottom and is attached to the liquid injection hole 300 </ b> A of the lid member 300. An opening 312 serving as a gas intake port is provided on the outer peripheral wall 311 of the liquid stopper 310. Therefore, the gas generated in the battery case enters the inside of the liquid port plug 310 through the opening 312 and is then exhausted to the outside through the exhaust port 313 formed in the upper surface wall.

  The liquid spout 310 has a splash-proof body 320 inside. The splash-proof body 320 functions to prevent the electrolytic solution splashed by vibration from leaking from the exhaust port 313. In addition, the bottom wall 325 of the splash-proof body 320 has a reflux hole 327. In the liquid stopper 310, the lower side of the bottom wall 325 of the splash-proof body 320 is a flow path L connected to the battery case 20 from the reflux hole 327, and droplets inside the liquid stopper pass through the reflux hole 327. After that, the liquid is returned to the battery case 20 from the bottom surface of the liquid spout 310 (the outlet of the flow path L).

  The liquid spout 310 includes a bottom lid 330. The bottom lid 330 is connected to the lower end portion of the liquid spout 310 via a hinge 331, and closes the bottom surface of the liquid spout 310 as the electrolyte level rises. Therefore, when the liquid level rises, it is possible to prevent gas or electrolyte from entering the inside of the liquid spout 310 from the bottom surface. Accordingly, the electrolytic solution is difficult to leak to the outside.

  (5) Moreover, the structure of the battery case 15 does not need to be the combination of the battery case 20 and the lid member 50 whose upper surfaces are open, and may be a combination of the battery case 20 and the lid member 50 whose side surfaces and the bottom surface are opened. Further, the installation location of the exhaust path R, the reflux hole 85, and the valve body is not necessarily limited to the lid member 50, and may be an upper portion of the battery case 15. For example, in a lead storage battery having a structure in which the bottom surface of the battery case is closed with a lid member, a configuration in which the liquid stopper 310 shown in FIG. 18 is provided on the top wall of the battery case may be employed.

  (6) In the first and second embodiments, the example in which the reflux hole 85 is surrounded by the cylinder 87 is shown, but the cylinder 87 is not necessarily required and can be eliminated. For example, in the case of a structure in which the reflux hole 85 is directly opened and closed with a lid-like valve body, it can be eliminated.

DESCRIPTION OF SYMBOLS 10 ... Lead acid battery 15 ... Battery case 20 ... Battery case 25 ... Cell chamber 30 ... Electrode group 50 ... Lid member 60 ... Middle lid 81 ... Lower exhaust pipe 85 ... Reflux hole 87 ... Cylinder 89 ... Hinge 90 ... Bottom cover (an example of the "valve" of the present invention)
DESCRIPTION OF SYMBOLS 100 ... Upper cover 131 ... Upper exhaust pipe 200 ... Float (an example of "valve" of the present invention)
310 ... Liquid spigot (an example of the “exhaust section” of the present invention)
V ... Droplet W ... Electrolyte L ... Flow path

Claims (5)

An electrode group;
An electrolyte,
A battery case containing the electrode group and the electrolyte,
The battery case is on the upper side of the case.
An exhaust part that takes in the gas generated in the battery case from a gas intake port and exhausts it to the outside;
A reflux unit that is provided separately from the gas intake port of the exhaust unit and recirculates droplets in the exhaust unit to a storage space that stores the electrolytic solution in the battery case;
A valve body that suppresses the electrolyte from entering the return part from the accommodation space by closing the flow path or the return part from the return part to the accommodation space when the electrolyte level rises; Lead acid battery comprising: The lead acid battery according to claim 1,
The valve body closes the flow path or the reflux portion by utilizing the rise in the electrolyte level in the battery case,
The lead acid battery which opens the said flow path or the said reflux part using the liquid level fall of the said electrolyte solution. The lead-acid battery according to claim 1 or 2,
The said valve body is a lead acid battery which closes the said flow path in the position away from the said reflux part. The lead-acid battery according to any one of claims 1 to 3,
The battery case is
The tube case is extended downward while surrounding the reflux portion from the upper wall of the battery case, and has a cylindrical body having the flow path inside.
The said valve body is a lead acid battery which opens and closes the said flow path formed in the said cylindrical body using the displacement of the liquid level of the said electrolyte solution. The lead-acid battery according to any one of claims 1 to 3,
The said valve body is a lead acid battery which is a float which opens and closes the said flow path or the said reflux part using the displacement of the liquid level of the said electrolyte solution.

Images