JP2019165012A - Lead storage battery, idling stop car and micro hybrid car - Google Patents

Abstract

To provide a lead storage battery capable of achieving both reduced liquid reduction performance and DCA performance.SOLUTION: The lead storage battery comprises: a battery case with open top; a positive electrode and negative electrode housed in a battery case; and a lid that closes the opening of the battery case. The negative electrode has a negative electrode active material which includes: a Pb component; lignin sulfonic acid and/or its salt; and a carbon material with a specific surface area of 10.0 m/g or less.SELECTED DRAWING: None

Description

  The present invention relates to a lead storage battery, an idling stop vehicle, and a micro hybrid vehicle.

  In recent years, various measures for improving fuel efficiency have been studied for automobiles in order to prevent air pollution or global warming. Examples of automobiles with measures to improve fuel efficiency include micro-hybrids such as an idling stop system vehicle (hereinafter referred to as “ISS vehicle”) that shortens the operating time of the engine and a power generation control vehicle that reduces the power generation of the alternator by the engine power. Cars are being considered.

  In an ISS vehicle, the number of engine starts increases, so that a large current discharge of the lead storage battery is repeated. Further, in the ISS vehicle and the micro hybrid vehicle, the amount of power generated by the alternator is reduced, and the lead storage battery is charged intermittently, so that the charging becomes insufficient. Therefore, the lead acid battery used in the ISS vehicle and the micro hybrid vehicle is used in a partially charged state called PSOC (Partial State Of Charge). When a lead storage battery is used under PSOC, the lifetime is shorter than when it is used in a fully charged state.

  In recent years, in Europe, the chargeability of lead-acid batteries during charge / discharge cycles in accordance with the control of micro-hybrid vehicles has been emphasized, and DCA (Dynamic) is an evaluation standard for the charge performance of lead-acid batteries during charge / discharge cycles. Charge Acceptance evaluation is being standardized. That is, in Europe, the DCA performance of a lead storage battery used in a partially charged state called PSOC is regarded as important.

  On the other hand, as means for improving cycle life characteristics (hereinafter referred to as “cycle characteristics”) and charging performance, Patent Document 1 listed below discloses carbon having a hollow shell structure and bisphenols and sulfites or amino acids. The technology regarding the lead acid battery provided with the negative electrode active material containing the formaldehyde condensate of this is disclosed.

JP 2003-338285 A

  By the way, in an ISS car and a micro hybrid car, although it is a short time, large current charge of a lead storage battery is repeated by regenerative charge etc. It is known that electrolysis of water in the electrolyte occurs when large current charging is repeated. When electrolysis occurs, oxygen gas and hydrogen gas generated by the decomposition of water are discharged out of the battery, so that the water in the electrolyte decreases. In addition, when the water in the electrolyte solution volatilizes due to a rise in the temperature in the battery, etc., and the electrolyte solution mist is generated, the electrolyte solution mist is discharged through the exhaust plug for discharging the gas, thereby further electrolyzing. Water in the liquid is reduced. As a result, the sulfuric acid concentration in the electrolytic solution increases, and the capacity decreases due to corrosion deterioration of the positive electrode. In addition, when the liquid level of the electrolytic solution is lowered and the electrode (negative electrode, etc.) is exposed from the electrolytic solution, the discharge capacity is drastically reduced, the connection between the electrode (negative electrode, etc.) and the strap or the strap itself is corroded A problem occurs. For this reason, when the amount of water in the electrolyte of the lead storage battery decreases, it is necessary to perform maintenance by replenishing the reduced amount of water. Therefore, for lead-acid batteries, it is required to suppress a decrease in water in the electrolyte from a maintenance-free viewpoint. In particular, in Europe, it is standard that maintenance is not performed. Therefore, suppressing the reduction of the electrolyte is an important issue along with improvement of DCA performance.

  On the other hand, in the method of Patent Document 1, it is difficult to suppress the decrease of the electrolyte solution, and it is difficult to achieve both the suppression of the decrease of the electrolyte and the DCA performance.

  Then, an object of this invention is to provide the lead storage battery which can make the suppression performance of liquid reduction and DCA performance compatible, and an idling stop vehicle and a micro hybrid vehicle provided with this lead storage battery.

  As a result of intensive studies, the inventors have made it possible to achieve both suppression of liquid reduction and DCA performance by incorporating a carbon material having a specific specific surface area and a specific additive into the negative electrode active material. The present inventors have found that the present invention can be accomplished and have completed the present invention.

One aspect of the present invention includes a battery case having a cell chamber and having an upper surface opened, an electrode group and an electrolyte contained in the cell chamber, and a lid for closing the opening. A lead-acid battery having a negative electrode and a positive electrode, the negative electrode having a negative electrode active material containing a Pb component, lignin sulfonic acid and / or a salt thereof, and a carbon material having a specific surface area of 10.0 m ² / g or less About.

  According to this lead storage battery, it is possible to achieve both suppression of liquid reduction and DCA performance. In addition, according to this lead storage battery, the cycle characteristics (DOD 17.5% life performance) evaluated according to the EN standard (European unified standard) can be sufficient. That is, according to one aspect of the present invention, it is possible to provide a lead storage battery that can satisfy the performance required in Europe as the performance of the lead storage battery used in the micro hybrid vehicle.

  In one embodiment, the content of lignin sulfonic acid and its salt is 0.05 to 0.5 mass% based on the total mass of the negative electrode active material.

  In one embodiment, the content of the carbon material is 0.2 to 3.5% by mass based on the total mass of the negative electrode active material.

  In one aspect, the lid includes a first lid portion, a second lid portion provided on the first lid portion, and an exhaust formed between the first lid portion and the second lid portion. And a reflux hole for refluxing the electrolytic solution into the cell chamber. The bottom wall of the first lid portion that separates the exhaust chamber from the cell chamber has a chamber.

In one embodiment, when the width of the cell chamber is X mm and the thickness of the electrode group is Y mm, X and Y satisfy the following conditional expression.
−1.1 ≦ X−Y ≦ 1.2

  In one embodiment, the distance between adjacent negative and positive electrodes is 0.4 to 0.8 mm.

In one embodiment, the specific surface area of the carbon material is 7.0 m ² / g or less or 1.0 m ² / g or less.

  Another aspect of the present invention relates to an idling stop system vehicle including the lead storage battery.

  Another aspect of the present invention relates to a microhybrid vehicle including the lead storage battery.

  According to the lead storage battery of the present invention, it is possible to achieve both the liquid reduction suppression performance and the DCA performance. Moreover, according to this invention, the application to the micro hybrid vehicle of a lead storage battery can be provided. Moreover, according to this invention, the application to the idling stop vehicle of a lead storage battery can be provided. That is, according to the present invention, it is possible to provide an idling stop vehicle and a micro-hybrid vehicle including the lead storage battery capable of achieving both the liquid reduction suppression performance and the DCA performance.

FIG. 1 is a perspective view showing the overall configuration and internal structure of a lead-acid battery according to one embodiment. FIG. 2 is a perspective view showing a battery case used in the lead storage battery of FIG. FIG. 3 is a sectional view taken along line III-III in FIG. 4 is a plan view of a first lid used in the lead storage battery of FIG. FIG. 5 is a bottom view of a second lid used in the lead storage battery of FIG. FIG. 6 is a cross-sectional view of the lid taken along line VI-VI in FIG. FIG. 7 is a perspective view of an electrode plate group used in the lead storage battery of FIG. FIG. 8 is a side view of the electrode plate group of FIG. 7 viewed from the stacking direction of the electrode plates.

  Hereinafter, embodiments of the present invention will be described in detail.

<Lead battery>
FIG. 1 is a perspective view showing an overall configuration of a lead storage battery according to an embodiment. The lead acid battery 1 shown in FIG. 1 is a liquid lead acid battery. As shown in FIG. 1, the lead storage battery 1 according to the present embodiment includes a battery case 2 whose upper surface is open, a lid 3 that closes the opening of the battery case 2, and an electrode plate group ( Electrode group) and an electrolytic solution (not shown).

(Battery case)
2 is a perspective view showing a battery case used in the lead storage battery of FIG. 1, and FIG. 3 is a cross-sectional view taken along line III-III of FIG. As shown in FIGS. 2 and 3, the battery case 2 has a rectangular parallelepiped shape, a rectangular bottom surface portion, a pair of long side surface portions adjacent to the long side portion of the bottom surface portion, and a short side portion of the bottom surface portion. And a pair of short side portions adjacent to each other. Below, let the direction along the long side part of a bottom face part, and the direction along the short side part of a bottom face part be the longitudinal direction and the transversal direction of the battery case 2, respectively. The battery case 2 is made of, for example, polypropylene.

  The inside of the battery case 2 is divided into six sections by five partition walls 21, and the first to sixth cell chambers 22 a to 22 f (hereinafter, depending on circumstances) so as to be arranged along the longitudinal direction of the battery case 2. "Cell chamber 22") is formed. The cell chamber 22 is a space into which the electrode plate group is inserted. The electrode plate group is accommodated in each cell chamber 22 of the battery case 2 such that the stacking direction of the electrode plates is the longitudinal direction of the battery case 2. The electrode plate group is also called a single cell, and the electromotive force is 2V. Since the electrical equipment for automobiles is driven by stepping up or down a DC voltage of 12V, six electrode plate groups are connected in series to make 2V × 6 = 12V. For this reason, when the lead storage battery 1 is used as an electrical component for automobiles, six cell chambers are required. In addition, when using the lead acid battery 1 for another use, the number of cell chambers is not limited to six pieces.

  As shown in FIG. 2 and FIG. 3, the height direction of the battery case 2 (direction perpendicular to the opening surface) is formed on both side surfaces of the partition wall 21 and the pair of inner wall surfaces 23 facing the partition wall 21 of the battery case 2. A plurality of ribs (rib portions) 24 may be provided. That is, the partition wall 21 may include a flat portion 25 and a plurality of ribs 24 extending in the height direction of the battery case 2 protruding from the flat portion 25. The rib 24 has a function of appropriately pressing (compressing) the electrode plate group inserted into the cell chamber 22 in the electrode plate stacking direction.

  The width X of each cell chamber 22 can be adjusted by the height of the ribs 24 and the like. The widths of the plurality of cell chambers 22 may be the same or different. In this specification, the width X of the cell chamber is the shortest distance between the facing partition walls 21 or the inner wall surface of the battery case 2 facing the partition wall 21 when the partition wall 21 does not have the ribs 24. 23 is defined as the shortest distance to 23 (hereinafter referred to as “inter-wall distance Xa”). When the partition wall 21 and / or the inner wall surface 23 of the battery case 2 have ribs, the width X of the cell chamber is defined as a value obtained by subtracting the highest rib height Ha from the inter-wall distance Xa (see FIG. 3). .) For example, when the heights Ha of the ribs of the two opposing partition walls 21 are the same, the width X of the cell chamber is [inter-wall distance Xa] − (2 × [rib height Ha]).

(lid)
As shown in FIG. 1, the lid 3 has a double lid structure composed of a first lid portion 4 and a second lid portion 5, and the first lid portion 4, the second lid portion 5, and the like. A plurality of exhaust chambers D1 to D6 are formed between them. That is, the lid 3 includes a first lid portion 4, a second lid portion 5, and an exhaust chamber formed between the first lid portion 4 and the second lid portion 5. The lid 3 has a substantially rectangular shape in plan view, and one end and the other end in the longitudinal direction of the lid 3 are connected to one end and the other end in the longitudinal direction of the battery case 2 among the directions along the four sides of the rectangle. Each of the lids 3 is provided on the battery case 2 in such a state that one end and the other end in the short direction of the lid 3 are respectively matched with one end and the other end of the battery case 2 in the short direction. The lid 3 (the first lid portion 4 and the second lid portion 5) is made of, for example, polypropylene.

  The lid 3 is formed with a hollow projecting portion 6 projecting upward from the upper surface of the first lid portion 4 in an area of the upper surface of the first lid portion 4 where the second lid portion 5 is not provided. ing. An indicator mounting hole 7 is formed in a part of the protruding portion 6. The indicator mounting hole 7 is used for mounting an indicator (not shown) that displays the liquid level of the electrolytic solution in the battery case. In the present embodiment, an indicator mounting hole 7 is provided above one of the cell chambers provided in the battery case 2, and an indicator for displaying the liquid level of the electrolytic solution in the cell chamber is provided. It can be attached to the indicator attachment hole 7. In the present embodiment, the liquid level of the electrolytic solution in one cell chamber is displayed on the indicator as a representative, thereby estimating the liquid level of the electrolytic solution in another cell chamber.

  In the lid 3, a negative electrode terminal 8 and a positive electrode terminal 9 are formed in a region where the second lid portion 5 is not provided on the upper surface of the first lid portion 4. The negative electrode terminal 8 and the positive electrode terminal 9 are connected to the electrode plate group accommodated in the battery case 2 through the negative electrode column and the positive electrode column.

  Hereinafter, the details of the lid 3 will be described with reference to FIGS. 4 to 6. FIG. 4 is a plan view of the first lid, and FIG. 5 is a bottom view of the second lid. 6 is a cross-sectional view taken along the line VI-VI in FIG. 4, and is a cross-sectional view of the lid 3 in a state where the first lid portion 4 and the second lid portion 5 are welded.

  As shown in FIG. 4, the first lid portion 4 has a substantially rectangular shape in plan view, and the second lid portion 5 is disposed on a part of the first lid portion 4. An exhaust chamber constituting part 400 is formed. The exhaust chamber constituting part 400 has one end 400a and the other end 400b in the longitudinal direction thereof positioned closer to the one end 4a and the other end 4b in the longitudinal direction of the first lid part 4, respectively, and one end 400c in the short side direction is set to the first end 400c. The lid portion 4 is positioned near the center in the short direction, and the other end 400d in the short direction is positioned near the other end 4d in the short direction of the first lid 4 (short direction of the battery case). It is formed in the state made to do. A peripheral wall portion 40 extending along the outer peripheral edge is formed on the upper surface of the exhaust chamber constituting portion 400, and a first lid-side concave portion is formed inside the peripheral wall portion 40. In the example shown in FIG. 4, in order to increase the width dimension (length in the short direction) of the portion near the one end 4 a in the longitudinal direction and the portion near the other end 4 b of the exhaust chamber constituting portion 400. Protrusions 401 and 402 projecting toward one end side in the lateral direction from the portion closer to the center in the longitudinal direction are formed.

  As shown in FIG. 5, the 2nd cover part 5 has the outline shape similar to the exhaust chamber structure part 400, and the exhaust chamber structure is each in the one end 5a side and the other end 5b side of the longitudinal direction. Similar to the protruding portions 401 and 402 at both ends of the portion 400, protruding portions 501 and 502 protruding in the short direction are formed. Further, as shown in FIG. 5, a peripheral wall portion 50 extending along the outer peripheral edge is formed on the lower surface of the second lid portion 5, and a second lid-side concave portion is formed inside the peripheral wall portion 50. ing. In the example shown in FIG. 5, an outer wall portion 51 that surrounds the outer side of the peripheral wall portion 50 is formed on the lower surface of the second lid portion 5.

  The 2nd cover part 5 is provided on the exhaust chamber structure part 400, and the 1st cover part 4 and the 2nd cover part 5 are joined by heat welding. Specifically, the second lid portion 5 has one end 5a and the other end 5b in the longitudinal direction of the second lid portion 5 aligned with one end 4a and the other end 4b in the longitudinal direction of the first lid portion 4, respectively. The exhaust chamber in a state where one end 5c and the other end 5d in the short direction of the second lid portion 5 are aligned with one end 400c and the other end 400d in the short direction of the exhaust chamber constituting portion of the first lid portion 4, respectively. Arranged on the component 400. The exhaust chamber constituting part 400 and the second lid part 5 are joined in a state in which the peripheral wall part 40 and the peripheral wall part 50 are combined, and the first lid part side recess and the second lid part side are joined. A space for forming an exhaust chamber is formed between the exhaust chamber constituting portion 400 of the first lid portion 4 and the second lid portion 5 by the recess.

  In the space between the exhaust chamber constituting portion 400 of the first lid portion 4 and the second lid portion 5, the first to sixth cell chambers 22a to 22f are respectively positioned on the first to sixth cell chambers 22a to 22f. Six exhaust chambers D1 to D6 are formed (see FIGS. 4 and 5). These exhaust chambers are a first partition wall portion having a predetermined pattern formed with a predetermined plate thickness inside the exhaust chamber constituting portion 400 of the first lid portion 4 and the peripheral wall portion 50 of the second lid portion 5. 42 and 52 are joined together. The exhaust chambers D <b> 1 to D <b> 6 have a function of retaining the mist of the electrolytic solution generated from each cell chamber 22 in the battery case 2 and refluxing the electrolytic solution liquefied in the exhaust chamber into each cell chamber 22. .

  In the present embodiment, a part of the first exhaust chamber D <b> 1 and the sixth exhaust chamber D <b> 6 arranged at both ends is replaced with a first partition wall portion provided in the first lid portion 4 and the second lid portion 5. By partitioning with second partition wall portions 42a and 52a formed in a part of 42 and 52, one end 400a side and the other end 400b side in the longitudinal direction of the exhaust chamber constituting portion 400 of the first lid portion 4, and Concentrated exhaust chambers E1 and E2 are formed on one end 5a side and the other end 5b side in the longitudinal direction of the second lid portion 5, respectively.

  Each exhaust chamber has a pair of opposing longitudinal inner surfaces Sa and Sb facing in the longitudinal direction of the first lid portion 4 and a pair of opposing opposing surfaces in the lateral direction of the first lid portion 4. Short side inner surfaces Sc and Sd, and four corner portions C1 to C4 are formed in each exhaust chamber. In the present specification, for convenience of explanation, of the four inner side surfaces Sa to Sd of each exhaust chamber, the inner side surfaces Sa and Sb facing the longitudinal direction of the first lid portion 4 are referred to as longitudinal inner side surfaces. The inner side surfaces Sc and Sd facing the short side direction of one lid portion 4 are referred to as short side inner side surfaces.

  In the three exhaust chambers D <b> 1 to D <b> 3 arranged near the one end 4 a in the longitudinal direction of the first lid portion 4, the first lid portion 4 among the pair of longitudinal inner surfaces of the first lid portion 4. The longitudinal inner surface located on the one end 4a side in the longitudinal direction is defined as one longitudinal inner surface Sa, and the longitudinal inner surface located on the other end 4b side in the longitudinal direction of the first lid portion 4 is disposed in the other longitudinal direction. The inner surface Sb is used. Further, in the other three exhaust chambers D4 to D6 arranged near the other end 4b in the longitudinal direction of the first lid portion 4, the longitudinal length of the first lid portion 4 among the pair of longitudinal inner surfaces. The longitudinal inner surface located on the other end 4b side in the direction is defined as one longitudinal inner surface Sa, and the longitudinal inner surface located on the one end 4a side in the longitudinal direction of the first lid portion 4 is defined as the other longitudinal inner surface. Sb.

  The exhaust chambers D <b> 1 to D <b> 6 are formed in a substantially square shape in plan view, but the first exhaust chamber D <b> 1 and the sixth exhaust chamber D <b> 6 disposed at both ends in the longitudinal direction of the first lid 4 are respectively As a result of the centralized exhaust chambers E1 and E2 being formed in a part of this, one of the longitudinal inner surfaces Sa has a deformed shape.

  As described above, the exhaust chambers D1 to D6 and the concentrated exhaust chambers E1 and E2 are formed between the exhaust chamber constituting portion 400 of the first lid portion 4 and the second lid portion 5, and further, As will be described later, various fluid passages for connecting the exhaust chambers D1 to D6 to the concentrated exhaust chambers E1 and E2 are formed. These fluid passages are configured by first partition portions 42 and 52 that are respectively provided in the first lid portion 4 and the second lid portion 5 and joined to each other. The configuration of the fluid passage provided between the first lid 4 and the second lid 5 will be described with reference to FIG. The patterns of the wall portions provided in the first lid portion and the second lid portion in order to form the exhaust chamber, the fluid passage, and the like are in a mirror image relationship with each other.

  As shown in FIG. 4, a first longitudinal fluid passage L1 and a second longitudinal fluid passage L2 are provided between the exhaust chamber constituting portion 400 of the first lid portion 4 and the second lid portion 5. And a first short direction fluid passage W1a and a second short direction fluid passage W1b are formed.

  The first longitudinal fluid passage L1 is on the other end 400d side in the short side direction of the exhaust chamber constituting portion 400, and the outside of the exhaust chambers D1 to D6 (between the exhaust chambers D1 to D6 and the peripheral wall portion 40) is an exhaust chamber. It is provided so as to extend linearly along the longitudinal direction of the component 400. On one end side and the other end side in the longitudinal direction of the first longitudinal fluid passage L1, there are width dimensions (lengths in the short direction) at positions corresponding to the protrusions 401 and 402 of the exhaust chamber constituting part 400, respectively. Enlarged enlarged portions L11 and L12 are formed. The end portions of the enlarged portions L11 and L12 of these first longitudinal fluid passages L1 are the flow paths 43 formed between the first exhaust chamber D1 and the sixth exhaust chamber D6 and the peripheral wall portion 40, respectively. 44 is connected to the central exhaust chambers E1 and E2.

  The second longitudinal fluid passage L2 is linearly connected to the outer side of the exhaust chambers D1 to D6 (between the exhaust chambers D1 to D6 and the peripheral wall 40) on the one end 400c side in the short direction of the exhaust chamber constituting portion 400. It is provided to extend. The first short-direction fluid passage W1a and the second short-direction fluid passage W1b are respectively provided between the second and third exhaust chambers D2 and D3 adjacent to each other and the fourth and fifth exhaust chambers D4 and D5. The first longitudinal fluid passage L1 and the second longitudinal fluid passage L2 are connected to each other so as to extend in the short direction of the exhaust chamber constituting portion 400.

  The second longitudinal fluid passage L2 is partitioned into a first part L2a and a second part L2b by a partition wall part 45 provided in the center part in the longitudinal direction of the exhaust chamber constituting part 400. The first longitudinal fluid passage L1 passes through the first lateral fluid passage W1a and the second lateral fluid passage W1b, and the first portion L2a and the second portion of the second longitudinal fluid passage L2. Each is connected to L2b.

  As shown in FIG. 4, electrolyte injection into the exhaust chambers D <b> 1 to D <b> 6 passes through the bottom wall portion of each exhaust chamber that partitions each exhaust chamber and the corresponding cell chamber 22 a to 22 f. A reflux hole h having a size also serving as a hole is provided. The reflux hole h is formed between one longitudinal inner side surface Sa of each exhaust chamber and one short side inner surface Sc of each exhaust chamber located on the second longitudinal fluid passage L2 side. It is located in the vicinity of one corner C1, and only one is provided in each exhaust chamber. The exhaust chambers D1 to D6 are connected to the first to sixth cell chambers 22a to 22f through the reflux holes h provided in the respective bottom walls.

  In each exhaust chamber of the first lid portion 4 and the second lid portion 5, fluid passage forming walls 46 and 56 extending along the other longitudinal inner side surface Sb of each exhaust chamber are provided. A third short-direction fluid passage W2 extending in the short direction of the exhaust chamber constituting portion 400 is formed between the fluid passage forming walls 46 and 56 and the inner surface Sb in the longitudinal direction. One end of the third short-side fluid passage W2 opens to the fourth corner portion C4 at a diagonal position of the first corner portion C1, and the other end opens into the second longitudinal fluid passage L2. is doing.

  In each exhaust chamber of the first lid portion 4 and the second lid portion 5, a fluid passage forming wall near the opening at one end of the third short-side fluid passage W <b> 2 (near the fourth corner portion C <b> 4). First barrier portions 47 and 57 integrated with the portions 46 and 56 are provided. The first barrier portions 47 and 57 protrude from the fluid passage forming wall portions 46 and 56 toward one longitudinal inner surface Sa of each exhaust chamber, and terminate at a position in front of the one longitudinal inner surface Sa. is doing. The first barrier portions 47 and 57 are provided so as to be integrated with the first lid portion 4 and the second lid portion 5. An electrolytic solution housing space A is formed between the first barrier portions 47 and 57 and one short side inner surface Sc. The end positions of the tips of the first barrier portions 47 and 57 are set so that at least a part of the reflux hole h is positioned in the electrolyte solution containing space A.

  In each exhaust chamber of the first lid portion 4 and the second lid portion 5, one longitudinal facing surface Sc of each exhaust chamber at a position closer to the first barrier portions 47 and 57 than the reflux hole h. The second barrier portions 48 and 58 are provided so as to protrude from the electrolyte solution storage space A and extend toward the fluid passage forming wall portions 46 and 56. The barrier portions 48 and 58 are provided integrally with the first lid portion 4 and the second lid portion 5. The second barrier portions 48 and 58 are inclined toward the second corner portion C2 formed between the other longitudinal inner side surface Sb and one shorter side inner surface Sc of each exhaust chamber. Is provided. The distal ends of the second barrier portions 48 and 58 are terminated at positions in front of the fluid passage forming wall portions 46 and 56.

  In each exhaust chamber of the first lid portion 4 and the second lid portion 5, a second barrier portion 48 is formed along the short direction of the exhaust chamber from a position just before the tips of the first barrier portions 47 and 57. , 58 are further provided, and first projecting wall portions 47a, 57a that are terminated at positions before the second barrier portions 48, 58 are further provided. Each exhaust chamber protrudes from the position in front of the front end of each of the second barrier portions 48 and 58 toward the short side inner surface Sc of each exhaust chamber and is positioned in front of the short side inner surface Sc. Second projecting wall portions 48a and 58a that are terminated at the end are further provided. The first protruding wall portions 47 a and 57 a and the second protruding wall portions 48 a and 58 a are provided integrally with the first lid portion 4 and the second lid portion 5.

  In the first lid portion 4, the upper surface of the bottom wall portion of each exhaust chamber gradually decreases from the vicinity of the opening at one end of the third short-side fluid passage W2 toward the reflux hole h. Is inclined. The bottom surface of the first longitudinal fluid passage L1 is gradually lowered toward the portion where the first and second short-side fluid passages W1a, W1b and the first longitudinal fluid passage L1 meet. Inclined to go. The bottom surfaces of the first and second short-side fluid passages W1a and W1b are inclined so as to gradually become lower from the first longitudinal fluid passage L1 side toward the second longitudinal fluid passage L2 side. It is attached. The bottom surface of the second longitudinal fluid passage L2 is inclined so as to gradually decrease toward the opening at the other end of the third short-side fluid passage W2 provided in each exhaust chamber. Yes. In FIG. 4, the inclination of each of the above parts is indicated by arrows. Each arrow indicates that the front end side is lower than the rear end side. With such a configuration, the mist of the electrolyte discharged from the recirculation holes h in the exhaust chambers into the exhaust chambers becomes the first barrier portions 47 and 57, the second barrier portions 48 and 58, and the first protruding walls. After liquefying by touching 47a, 57a and the second projecting walls 48a, 58a, it is possible to return to the return holes h of the exhaust chambers along the bottom surfaces of the exhaust chambers.

  As shown in FIG. 5, an exhaust port 65 for opening the concentrated exhaust chambers E1 and E2 to the outside is formed at one end and the other end of the second lid portion 5 in the longitudinal direction. Explosion-proof filters 66 are accommodated in the central exhaust chambers E1 and E2. Exhaust gas flowing into each concentrated exhaust chamber through the first longitudinal fluid passage L1 is exhausted to the outside through the explosion-proof filter 66 and the exhaust port 65.

  A liquid injection port 60 is formed in the second lid portion 5. The liquid injection port 60 is provided at a position aligned with the reflux hole h in each exhaust chamber. A screw for attaching a stopper is formed on the inner periphery of the liquid injection port 60.

  As shown in FIG. 6, the lid 3 is provided with a welded portion 405 and positioning ribs 406. The welded portion 405 is welded to the upper end of the partition wall that partitions the cell chambers in the battery case when the lid 3 is attached to the battery case 2, and forms a wall portion that separates the cell chambers together with the partition wall on the battery case side. To do. Further, the positioning rib 406 engages with the side surface of the upper end of the partition wall between the cell chambers on the battery case side when the welding portion 405 is welded to the upper end of the partition wall between the cell chambers of the battery case 2. It is a positioning rib for positioning 405 with respect to the partition on the battery case side.

(Plate group)
FIG. 7 is a perspective view of the electrode plate group (electrode group) 10. As shown in FIG. 7, the electrode plate group 10 includes a plate-like negative electrode (negative electrode plate) 11, a plate-like positive electrode (positive electrode plate) 12, and a separator disposed between the negative electrode plate 11 and the positive electrode plate 12. 13. The electrode plate group 10 has a structure in which a plurality of negative electrode plates 11 and positive electrode plates 12 are alternately stacked in the longitudinal direction of the battery case 2 via separators 13. That is, the negative electrode plate 11 and the positive electrode plate 12 are arranged so that their main surfaces extend in a direction perpendicular to the opening surface of the battery case 2. The electrode plate group 10 has a rectangular shape in which the height direction of the battery case 2 is the short direction and the short direction of the battery case 2 is the long direction as viewed from the stacking direction of the electrode plates.

  In the electrode plate group 10, the ear portions 11 a of the plurality of negative electrode plates 11 are collectively welded by the negative electrode side strap 101. Similarly, the ears 12 a of the plurality of positive electrode plates 12 are collectively welded by the positive straps 102. In the lead storage battery 1, each of the negative electrode side strap 101 and the positive electrode side strap 102 is connected to the negative electrode terminal 8 and the positive electrode terminal 9 via the negative electrode column and the positive electrode column.

  As shown in FIG. 7, the negative electrode plate 11 includes a current collector (negative electrode current collector) 14 and a negative electrode active material held by the current collector 14, and the negative electrode active material is a negative electrode active material. A substance filling unit 15 is configured. The positive electrode 12 includes a current collector (positive electrode current collector) 16 and a positive electrode active material held by the current collector 16, and the positive electrode active material constitutes a positive electrode active material filling unit 17. is doing. In the present embodiment, the negative electrode active material is a negative electrode active material after chemical conversion (for example, in a fully charged state), and the positive electrode active material is a positive electrode active material after chemical conversion (for example, in a fully charged state). When the electrode active material (negative electrode active material and positive electrode active material) is unformed, the unformed electrode active material (unformed negative electrode active material and unformed positive electrode active material) is the electrode active material (negative electrode active material and Positive electrode active material) and the like. In the present specification, a material obtained by removing the positive electrode current collector from the formed positive electrode plate is referred to as a “positive electrode active material”, and a material obtained by removing the negative electrode current collector from the formed negative electrode plate is referred to as a “negative electrode active material”. .

  The separator 13 is formed in a bag shape and accommodates the negative electrode plate 11 therein. A plurality of convex ribs 18 are provided on the surface of the separator 13 opposite to the negative electrode plate 11 (surface on the positive electrode plate 12 side) so as to extend in the short direction of the separator 13 (short direction of the electrode plate group 10). Is formed.

  The thickness Y of the electrode plate group 10 described above is not particularly limited, and can be adjusted by the thickness of the electrode plates (the negative electrode plate 11 and the positive electrode plate 12), the thickness of the separator 13, the distance between the electrode plates, and the like. In the present specification, the thickness Y of the electrode plate group means the thickness of the electrode plate group in a state where the compression force from the battery case 2 is not applied to the electrode plate group 10.

  A method of measuring the thickness Y of the electrode plate group 10 will be specifically described with reference to FIG. FIG. 8 is a side view of the electrode plate group 10 viewed from the stacking direction of the electrode plates (the negative electrode plate 11 and the positive electrode plate 12). The thickness of the electrode plate group 10 is such that the electrode active material filling portion (the negative electrode active material filling portion 15 in FIG. 8) of the electrode plate (the negative electrode plate 11 in FIG. 8) on the outermost side of the electrode plate group 10 One point at the center T1 in the longitudinal direction of the electrode plate group 10 in the range r of ± 3 mm in the short direction from the boundary with the frame portion located on the ear portion side of the current collector of the electrode plate, an arbitrary right side from the center Is defined as an average value of the thickness of the electrode plate group 10 measured at a total of three points, one point at the position T2 and one point at an arbitrary position T3 on the left side of the center. However, as shown in FIG. 7, when the separator is disposed on the outermost side of the electrode plate group 10, the height of the rib 18 of the separator is not included in the thickness of the electrode plate group 10. That is, when the separator 13 is disposed on the outermost side of the electrode plate group 10, the thickness of the electrode plate group 10 is measured at the position of the portion (base portion) 19 that supports the rib 18 in the separator 13. The thickness Y of the electrode plate group 10 in the lead-acid battery after chemical conversion is, for example, sufficient for a system in which the electrode plate group 10 after chemical conversion is taken out and washed with water for 1 hour and the sulfuric acid-removed electrode plate group 10 is free of oxygen. It can be measured after drying.

  The distance between the negative electrode plate 11 and the positive electrode plate 12 that are adjacent to each other via the separator 13 in the electrode plate group 10 (distance between electrode plates, distance between electrodes) can suppress a decrease in electrolyte more sufficiently, and can suppress a short circuit. From the viewpoint, it is preferably 0.4 mm or more, more preferably 0.5 mm or more, and further preferably 0.55 mm or more. The distance between the electrode plates is preferably 0.8 mm or less, more preferably 0.75 mm or less, still more preferably 0.7 mm or less, from the viewpoint of more sufficiently suppressing the decrease in the electrolyte. Preferably it is 0.65 mm or less, Most preferably, it is 0.6 mm or less. From these viewpoints, the distance between the electrode plates is preferably 0.4 to 0.8 mm, more preferably 0.4 to 0.75 mm, still more preferably 0.5 to 0.7 mm. More preferably, it is 0.55-0.65 mm, Most preferably, it is 0.55-0.6 mm. The distance between the electrode plates means the distance between the electrode plates in a state where the compressive force from the battery case 2 is not applied to the electrode plate group 10.

  When the electrode plate and the separator 13 are in contact with each other, for example, all the separators 13 are extracted from the electrode plate group 10, and the upper ends of the separators 13 (the ends on the ear side in the short direction) are extracted. Part) (13a in FIG. 7) to the lower end (end opposite to the ear part side in the short side direction) (13b in FIG. 7), the thickness of the separator 13 is measured at about 8 mm. The average value of the measured values can be used as the distance between the electrode plates. When the separator 13 has the rib 18, the thickness of the separator 13 is the sum of the thickness of the base portion 19 and the height of the rib 18. For example, among the ribs 18 formed in the longitudinal direction of the separator 13, the thickness measured at a total of three points on the two ribs arranged on the outermost side and the rib arranged on the midpoint thereof. Let the average value be the thickness of the separator 13. When the separator 13 does not have the rib 18, the thickness measured at three points in total: one point at the center in the longitudinal direction of the separator 13, one point at an arbitrary position to the right of the center, and one point at an arbitrary position to the left of the center. Let the average value of the thickness be the thickness of the separator 13. In addition, when the separator 13 is bag shape, the separator 13 is expand | deployed and thickness is measured. In addition, the distance between the electrode plates in the state in which the compression force is not applied to the electrode plate group 10 in the lead storage battery 1 after chemical conversion is taken out from the lead acid battery 1 after conversion and washed with water for 1 hour. After the electrode plate group 10 from which the liquid (for example, sulfuric acid) has been removed is sufficiently dried in a system without oxygen, the measurement can be performed by the above method.

  In the lead storage battery 1 according to the present embodiment, the difference (clearance: XY) between the width X (mm) of the cell chamber 22 in the battery case 2 and the thickness Y (mm) of the electrode plate group 10 is, for example, -1. .1 to 1.2 mm. When the value of the clearance (X−Y) is −1.1 mm or more, the decrease in the electrolytic solution can be sufficiently suppressed, and the short circuit tends to be suppressed. Moreover, there exists a tendency which can fully suppress the reduction | decrease of electrolyte solution because clearance (XY) is 1.2 mm or less. The clearance (X—Y) is preferably −1.0 mm or more, more preferably −0.6 mm or more, from the viewpoint that the decrease of the electrolytic solution can be more sufficiently suppressed and a short circuit can be further suppressed. The clearance (XY) is preferably 1.0 mm or less, more preferably 0.0 mm or less, and still more preferably less than 0.0 mm, from the viewpoint that the decrease in the electrolyte can be more sufficiently suppressed. From these viewpoints, the clearance (XY) may be −1.0 to 1.0 mm, may be −0.6 to 0.0 mm, and may be −0.6 mm or more and −0.0 mm. It may be less.

  Next, details of the negative electrode active material, the positive electrode active material, the current collector, and the separator will be described.

(Negative electrode active material)
The negative electrode active material contains at least Pb alone as a Pb component (lead component), and further contains a Pb component other than Pb alone (for example, PbSO ₄ ) and an additive described later as necessary. Specifically, the negative electrode active material includes (A) a Pb component (hereinafter also referred to as “(A) component”), (B) lignin sulfonic acid and / or a salt thereof (hereinafter referred to as “(B) component”). And (C) a carbon material having a specific surface area of 10.0 m ² / g or less (hereinafter also referred to as “component (C)”).

[(A) component: Pb component]
Examples of the component (A) include spongy lead. Spongy lead tends to react with sulfuric acid in the electrolyte and gradually change to lead sulfate (PbSO ₄ ). The negative electrode active material containing component (A) is obtained by aging and drying a negative electrode active material paste containing a raw material for the negative electrode active material to obtain an unformed negative electrode active material and then forming the negative electrode active material. be able to. Examples of the raw material for the negative electrode active material include lead powder. As the lead powder, for example, lead powder manufactured by a ball mill type lead powder manufacturing machine or a barton pot type lead powder manufacturing machine (in the ball mill type lead powder manufacturing machine, a mixture of powder of main component PbO and scale-like metal lead) ). The unformed negative electrode active material is composed of, for example, basic lead sulfate, metallic lead, and a lower oxide.

  The content of the component (A) is 93% by mass or more based on the total mass of the negative electrode active material from the viewpoint of further excellent battery characteristics (battery capacity, discharge characteristics (low temperature high rate discharge characteristics, etc.), cycle characteristics, etc.) It may be 95 mass% or more, may be 98 mass% or more, may be 99 mass% or more, and may be 99.5 mass% or more. The content of the component (A) may be 99.99% by mass or less, 99.95% by mass or less, and 99.90% by mass or less based on the total mass of the negative electrode active material. Good. From these viewpoints, the content of the component (A) is 93 to 99.99 mass%, 93 to 99.95 mass%, 93 to 99.90 mass%, 95 to 99.99 mass%, and 95 to 99.99. It may be 95 mass%, 95-99.90 mass%, 98-99.99 mass%, 98-99.95 mass%, or 98-99.90 mass%.

[(B) component: lignin sulfonic acid and / or salt thereof]
Lignin sulfonic acid is a compound in which a part of the degradation product of lignin is sulfonated, has a structural unit derived from lignin as a structural unit derived from a phenolic compound, and has a sulfonic acid group. Yes. Here, lignin is a polymer compound obtained by oxidative polymerization of monolignol by an enzyme. Examples of monolignol include p-hydroxycinnamic alcohol analogs such as coniferyl alcohol, sinapyr alcohol, and p-coumaryl alcohol. Can be mentioned. Lignin sulfonate is an alkali metal salt of the above lignin sulfonic acid and has a sulfonate group. Examples of lignin sulfonate include sodium lignin sulfonate and potassium lignin sulfonate.

  The component (B) has, for example, a structure in which a sulfonic acid group or a sulfonate group is bonded to the α-position carbon atom adjacent to the phenylene group.

  The weight average molecular weight of the component (B) is preferably 3000 or more, more preferably 7000 or more, from the viewpoint of suppressing the elution of the component (B) from the negative electrode active material and obtaining excellent DCA performance and cycle characteristics. More preferably, it is 8000 or more. The weight average molecular weight of the component (B) is preferably 50000 or less, more preferably 30000 or less, and further preferably 20000 or less, from the viewpoint of excellent dispersibility of the electrode active material. From these viewpoints, the weight average molecular weight of the component (B) may be 3000 to 50000, may be 7000 to 30000, and may be 8000 to 20000.

The weight average molecular weight of the component (B) can be measured, for example, by gel permeation chromatography (hereinafter referred to as “GPC”) under the following conditions.
(GPC conditions)
Apparatus: High performance liquid chromatograph LC-2200 Plus (manufactured by JASCO Corporation)
Pump: PU-2080
Differential refractometer: RI-2031
Detector: UV-visible spectrophotometer UV-2075 (λ: 254 nm)
Column oven: CO-2065
Column: TSKgel SuperAW (4000), TSKgel SuperAW (3000), TSKgel SuperAW (2500) (manufactured by Tosoh Corporation)
Column temperature: 40 ° C
Eluent: methanol solution containing LiBr (10 mM) and triethylamine (200 mM) Flow rate: 0.6 mL / min Molecular weight standard sample: Polyethylene glycol (molecular weight: 1.10 × 10 ⁶ , 5.80 × 10 ⁵ , 2.55 × 10 ⁵ , 1.46 × 10 ⁵ , 1.01 × 10 ⁵ , 4.49 × 10 ⁴ , 2.70 × 10 ⁴ , 2.10 × 10 ⁴ ; manufactured by Tosoh Corporation), diethylene glycol (molecular weight: 1 .06 × 10 ² ; manufactured by Kishida Chemical Co., Ltd.), dibutylhydroxytoluene (molecular weight: 2.20 × 10 ² ; manufactured by Kishida Chemical Co., Ltd.)

  The content of the component (B) may be 0.05% by mass or more and 0.1% by mass or more based on the total mass of the negative electrode active material from the viewpoint of obtaining excellent cycle characteristics. 0.15% by mass or more and 0.2% by mass or more. The content of the component (B) may be 0.5% by mass or less and 0.4% by mass or less, based on the total mass of the negative electrode active material, from the viewpoint of maintaining good liquid reduction performance. 0.35 mass% or less, and 0.3 mass% or less. From these viewpoints, the content of the component (B) is 0.05 to 0.5 mass%, 0.1 to 0.4 mass%, 0.15 to 0.35 mass%, or 0.2 to 0.00. It may be 3% by weight.

[(C) component: carbon material]
Component (C) is a carbon material such as carbon black or graphite. Examples of carbon black include furnace black, channel black, acetylene black, thermal black, and ketjen black.

(C) The specific surface area of a component is 10.0 m < ² > / g or less. In this embodiment, since the specific surface area of (C) component is 10.0 m < ² > / g or less, sufficient suppression effect of liquid reduction and DCA performance are obtained. The specific surface area of the component (C) is preferably 7.0 m ² / g or less, more preferably 5.0 m ² / g or less, from the viewpoint of obtaining a sufficient liquid-reducing suppression effect and DCA performance. More preferably, it is 3.0 m < ² > / g or less, More preferably, it is 2.0 m < ² > / g or less, Most preferably, it is 1.0 m < ² > / g or less. The specific surface area of the component (C) is preferably 0.5 m ² / g or more, more preferably 0.7 m ² / g or more, from the viewpoint of obtaining a sufficient liquid reduction suppressing effect and DCA performance. More preferably, it is 0.8 m ² / g or more. From these viewpoints, the specific surface area of component ^{(C), 0.5~10.0m 2 /g,0.5~7.0m 2 /g,0.5~5.0m 2 /g,0.5 ~3.0m 2 /g,0.5~2.0m 2 /g,0.5~1.0m 2 /g,0.7~3.0m 2} /g,0.7~2.0m 2 / ^g, may be 0.7~1.0m ² /g,0.8~2.0m 2 / g or 0.8~1.0m ² / g.

  The specific surface area of the component (C) can be measured by, for example, the BET method. The BET method is a method in which an inert gas (for example, nitrogen gas) having a known molecular size is adsorbed on the surface of a measurement sample, and the surface area is obtained from the adsorption amount and the area occupied by the inert gas. This is a general method for measuring the surface area. Specifically, for example, it can be measured under the following conditions.

[Specific surface area measurement conditions]
Apparatus: Macsorb Automatic Surface Area Analyzer (manufactured by Mountaintech)
Measurement method: BET method Adsorbed gas: Nitrogen Flow rate: 25 mL / min

  The content of the component (C) may be 0.2% by mass or more and 0.5% by mass or more based on the total mass of the negative electrode active material from the viewpoint of obtaining sufficient DCA performance and cycle characteristics. It may be 1.0 mass% or more, and may be 1.5 mass% or more. The content of the component (C) may be 3.5% by mass or less and 3.0% by mass or less based on the total mass of the negative electrode active material from the viewpoint of obtaining a sufficient liquid reduction inhibiting effect. It may be 2.5 mass% or less, and may be 2.0 mass% or less. From these viewpoints, the content of the component (C) is 0.2 to 3.5% by mass, 0.5 to 3.0% by mass, 1.0 to 2.5% by mass, or 1.5 to 2.%. It may be 0% by mass.

[Other ingredients]
The negative electrode active material may further contain other components other than the component (A), the component (B), and the component (C). Examples of other components include barium sulfate and reinforcing short fibers. Examples of the reinforcing short fibers include acrylic fibers, polyethylene fibers, polypropylene fibers, and polyethylene terephthalate fibers. The content of barium sulfate may be, for example, 0.5% by mass or more and 3.0% by mass or less based on the total mass of the negative electrode active material. The content of the reinforcing short fibers may be, for example, 0.05% by mass or more and 0.3% by mass or less based on the total mass of the negative electrode active material.

(Positive electrode active material)
The positive electrode active material includes PbO ₂ as a Pb component, and further includes a Pb component other than PbO ₂ (for example, PbSO ₄ ) and an additive to be described later as necessary. The positive electrode active material preferably contains β-lead dioxide (β-PbO ₂ ) as the Pb component, and may further contain α-lead dioxide (α-PbO ₂ ). The positive electrode active material can be obtained by aging and drying a positive electrode active material paste containing a raw material for the positive electrode active material to obtain an unformed positive electrode active material and then forming the positive electrode active material. There is no restriction | limiting in particular as a raw material of a positive electrode active material, For example, lead powder is mentioned. As the lead powder, for example, lead powder manufactured by a ball mill type lead powder manufacturing machine or a barton pot type lead powder manufacturing machine (in the ball mill type lead powder manufacturing machine, a mixture of powder of main component PbO and scale-like metal lead) ). Red lead as a raw material of the positive electrode active material _(Pb 3 _{O 4)} may be used. The unchemically formed positive electrode active material preferably contains tribasic lead sulfate as a main component.

  The content of the Pb component is preferably 95% by mass or more based on the total mass of the positive electrode active material from the viewpoint of further improving battery characteristics (capacity, discharge characteristics (low temperature high rate discharge characteristics, etc.), cycle characteristics, etc.). Yes, more preferably 97% by mass or more, and still more preferably 99% by mass or more.

  The positive electrode active material may further contain an additive. Examples of the additive include carbon materials (carbonaceous conductive materials), reinforcing short fibers, and the like. Examples of the carbon material include carbon black and graphite. Examples of the carbon black include furnace black (for example, oil furnace black such as Ketjen Black (registered trademark)), channel black, acetylene black, thermal black, and the like. Examples of the reinforcing short fibers include acrylic fibers, polyethylene fibers, polypropylene fibers, and polyethylene terephthalate fibers.

(Current collector)
The current collector constitutes a conductive path for current from the electrode active material. Examples of the current collector include a current collector manufactured by a method such as a casting method or an expanding method. Examples of the current collector material include a lead-calcium-tin alloy and a lead-antimony alloy. A small amount of selenium, silver, bismuth or the like can be added to these. The current collectors of the positive electrode and the negative electrode may be the same as or different from each other.

(Separator)
The separator has a function of preventing electrical connection between the positive electrode and the negative electrode and permeating sulfate ions of the electrolytic solution. Examples of the material forming the separator include polyethylene (PE) and polypropylene (PP). The separator may be one in which inorganic particles such as SiO ₂ and Al ₂ O ₃ are attached to a woven fabric, a nonwoven fabric, a porous film or the like formed of these materials. The shape of the separator is not particularly limited. For example, the separator may have a bag shape, and the positive electrode or the negative electrode plate may be accommodated in the bag-shaped separator.

According to the lead storage battery 1 of the said embodiment, the suppression performance of liquid reduction and DCA performance can be made compatible. The reason why such an effect is obtained is not clear, but it is because the negative electrode 11 includes lignin sulfonic acid and / or a salt thereof, and a carbon material having a specific surface area of 10.0 m ² / g or less. I guess that. That is, since the carbon material has the specific surface area described above, it is assumed that lignin sulfonic acid and / or a salt thereof is easily adsorbed on the carbon material, and that the carbon material is difficult to be taken into the Pb component. Is done. As a result, a decrease in the hydrogenation voltage due to the carbon material can be suppressed and high conductivity can be maintained, so that it is presumed that both the liquid reduction suppression performance and the DCA performance can be achieved.

Moreover, since the negative electrode 11 contains the lignin sulfonic acid and / or its salt, and the carbon material whose specific surface area is 10.0 m < ² > / g or less, the lead acid battery 1 of the said embodiment is evaluated according to EN specification. Excellent cycle characteristics.

  In the lead storage battery 1 of the above embodiment, the lid 3 is formed between the first lid portion 4, the second lid portion 5, and the first lid portion 4 and the second lid portion 5. The exhaust chambers D1 to D6, and the exhaust chamber keeps the mist of the electrolyte solution from each cell chamber 22 in the battery case 2 inside, and the electrolyte solution liquefied in the exhaust chamber is stored in each cell. Since it is comprised so that it can be made to recirculate | reflux indoors, according to the lead storage battery 1 of the said embodiment, the suppression effect of the outstanding liquid reduction is acquired.

  Further, in the lead storage battery 1 described above, when the gas pressure in the first to sixth cell chambers rises, the gas flowing out from the cell chambers through the reflux holes h into the first to sixth exhaust chambers, After flowing into the second longitudinal fluid passage L2 through the space in each exhaust chamber and the third short fluid passage W2 provided in each exhaust chamber, the first and second short fluid passages It flows into the first longitudinal fluid passage L1 through W1a and W1b. The gas flowing into the first longitudinal fluid passage L1 reaches the concentrated exhaust chambers E1 and E2, and is discharged to the outside through the exhaust port 65 from these concentrated exhaust chambers.

  The lead storage battery 1 described above is suitably used as a lead storage battery for an idling stop system vehicle or a micro hybrid vehicle. That is, one embodiment of the present invention is an application of the above-described lead-acid battery 1 to an idling stop system vehicle or a micro hybrid vehicle.

<Method for producing lead-acid battery>
The manufacturing method of the lead storage battery 1 which concerns on this embodiment is the assembly process of assembling the electrode plate manufacturing process which obtains an electrode plate (the negative electrode plate 11 and the positive electrode plate 12), and the structural member containing an electrode plate, for example. And.

  In the electrode plate manufacturing process, for example, an electrode active material paste (a positive electrode active material paste and a negative electrode active material paste) is filled in a current collector (for example, a cast lattice body and an expanded lattice body) and then aged and dried. An unformed electrode is obtained. The positive electrode active material paste contains, for example, a raw material (lead powder or the like) of the positive electrode active material, and may further contain other additives. The negative electrode active material paste contains a raw material (lead powder or the like) of the negative electrode active material, the component (B) and the component (C), and may further contain other components described above.

The positive electrode active material paste can be obtained, for example, by the following method. First, an additive (such as reinforcing short fibers) and water are added to the raw material of the positive electrode active material. Next, after adding dilute sulfuric acid, it is kneaded to obtain a positive electrode active material paste. In producing the positive electrode active material paste, lead (Pb ₃ O ₄ ) may be used as a raw material for the positive electrode active material from the viewpoint of shortening the formation time. After filling the positive electrode active material paste into the current collector, aging and drying can be performed to obtain an unformed positive electrode plate.

  A preferable aging condition for obtaining an unformed positive electrode plate is 15 to 60 hours in an atmosphere of a temperature of 35 to 85 ° C. and a humidity of 50 to 98 RH%. Preferred drying conditions are a temperature of 45 to 80 ° C. and a time of 15 to 30 hours.

  The negative electrode active material paste can be obtained, for example, by the following method. First, the mixture is obtained by adding (B) component, (C) component and other optional components (reinforcing short fibers, barium sulfate, etc.) to the negative electrode active material and dry mixing them. Next, a solvent (water such as ion-exchanged water or an organic solvent) is added to the mixture and kneaded. And a negative electrode active material paste is obtained by adding and knead | mixing a sulfuric acid (dilute sulfuric acid etc.). An unformed negative electrode plate can be obtained by filling the negative electrode active material paste into the current collector and then aging and drying.

  Preferred aging conditions for obtaining an unformed negative electrode plate are 15 to 30 hours in an atmosphere of a temperature of 45 to 65 ° C. and a humidity of 70 to 98 RH%. Preferred drying conditions are a temperature of 45 to 60 ° C. and a time of 15 to 30 hours.

  In the assembling process, for example, an unformed negative electrode plate and an unformed positive electrode plate are alternately laminated via separators 13, and the current collecting portions (ear portions) of the same polarity electrode plates are connected by a strap (welding, etc.) To obtain the electrode plate group 10. The electrode plate group 10 is accommodated in each cell chamber 22 of the battery case 2, and the negative electrode side strap 101 and the positive electrode side strap 102 of the electrode plate group 10 in the adjacent cell chamber 22 are separated from each other by the cell chamber 22. Then, the lid 3 is attached to the upper end of the battery case 2 after being connected by the inter-cell connecting portion penetrating the partition wall 21. Next, an electrolytic solution (dilute sulfuric acid or the like) is injected into each cell chamber 22 from a liquid injection port 60 provided in the second lid portion 5. After injecting the electrolytic solution into each cell chamber, the liquid injection port 60 is closed with a stopper. Thereby, an unformed battery is obtained. Next, a direct current is applied to form a battery case. The lead acid battery 1 is obtained by adjusting the specific gravity of the electrolytic solution after the formation to an appropriate specific gravity.

  The chemical conversion conditions and the specific gravity of sulfuric acid can be adjusted according to the properties of the electrode active material. Further, the chemical conversion treatment is not limited to being performed after the assembly process, and may be performed by immersing a large number of electrode plates after aging and drying in the electrode plate manufacturing process together in a chemical conversion tank (tank chemical conversion).

  As mentioned above, although the lead acid battery of one embodiment of the present invention was explained, the present invention is not limited to the above-mentioned embodiment.

  In the above embodiment, the liquid injection hole is provided in the second lid portion 5, but the liquid injection hole is not provided in the second lid portion 5, and after the electrolyte solution is injected, the first lid portion 4 is provided. And the second lid 5 may be welded together.

  In the above embodiment, among the pair of short-side inner surfaces Sc and Sd of each exhaust chamber, Sc is one short-side inner surface and Sd is the other short-side inner surface, but Sd and Sc May be used as one short side inner side and the other short side inner side. Similarly, Sb may be one longitudinal inner surface and Sa may be the other longitudinal inner surface.

  In the above embodiment, the reflux hole h is constituted by an assembly of a plurality of holes, but the reflux hole h may be constituted by a single hole.

  Further, the reflux hole h can be configured to have a larger function, or the number of holes constituting the reflux hole h can be increased, so that the reflux hole h can have a function as a vent hole.

  In the above embodiment, the first protruding wall portions 47a and 57a and the second protruding wall portions 48a and 58a may not be provided.

  Moreover, although the lead acid battery of the said embodiment is a liquid type lead acid battery, it is not limited to this, For example, a control valve type lead acid battery, a sealed lead acid battery, etc. may be sufficient. As a basic configuration of the lead storage battery, the same configuration as that of a conventional lead storage battery can be used.

  Hereinafter, the present invention will be described specifically by way of examples. However, the present invention is not limited to the following examples.

<Example 1>
(Preparation of battery case)
A battery case was prepared, which was composed of a box whose upper surface was opened and whose interior was divided into six cell chambers by partition walls.

(Preparation of positive electrode plate)
To the lead powder, 0.25% by mass of acrylic fiber (based on the total mass of the lead powder) was added as a reinforcing short fiber and dry mixed. Next, 3% by mass of water and 30% by mass of dilute sulfuric acid (specific gravity 1.55) were added to the obtained mixture containing lead powder and kneaded for 1 hour to prepare a positive electrode active material paste. In preparing the positive electrode active material paste, dilute sulfuric acid (specific gravity 1.55) was added stepwise in order to avoid a rapid temperature rise. The blending amounts of water and dilute sulfuric acid are blending amounts based on the total mass of lead powder and reinforcing short fibers.

  An expanded current collector produced by subjecting a rolled sheet made of a lead alloy to an expanding process was filled with a positive electrode active material paste, and then aged for 24 hours in an atmosphere at a temperature of 50 ° C. and a humidity of 98%. Then, it dried at the temperature of 50 degreeC for 16 hours, and produced the positive electrode plate which has a non-chemically formed positive electrode active material.

(Preparation of negative electrode plate)
Lead powder was used as a raw material for the negative electrode active material. Mixture of sodium lignin sulfonate (Nippon Paper Industries Co., Ltd., trade name: Vanillex N), carbon material (graphite with a specific surface area of 0.9 m ² / g), polyethylene terephthalate fiber (cut fiber, fiber length: 3 mm) and barium sulfate Was added to the lead powder and then dry mixed. Next, the mixture was kneaded after adding water. Subsequently, the mixture was kneaded while dilute sulfuric acid having a specific gravity of 1.280 was added little by little to prepare a negative electrode active material paste. The negative electrode active material paste was filled in an expandable current collector produced by subjecting a rolled sheet made of a lead alloy to an expanding process, and then aged for 24 hours in an atmosphere of a temperature of 50 ° C. and a humidity of 98%. Thereafter, drying was performed to prepare a negative electrode plate having an unformed negative electrode active material. In addition, sodium lignin sulfonate, carbon material, polyethylene terephthalate fiber and barium sulfate have a content (% by mass) based on the total mass of the negative electrode active material after chemical conversion, 0.2% by mass and 1.5%, respectively. It mix | blended so that it might become mass%, 0.1 mass%, and 1.5 mass%.

(Battery assembly)
An unformed negative electrode plate was inserted into a polyethylene separator processed into a bag shape. Next, five unchemically formed positive electrode plates and six unchemically formed negative electrode plates inserted in a bag-like separator were alternately laminated. Subsequently, the ears of the electrode plates having the same polarity were welded to each other by a cast-on-strap (COS) method to produce an electrode plate group. Six electrode plates were prepared and inserted into a battery case to assemble a 12V cell battery of EN standard (rank performance: 370, size: LN2). At this time, the lid having the exhaust chamber of the above-described embodiment shown in FIGS. 4 to 6 was used as the lid. Thereafter, a sulfuric acid solution having a specific gravity of 1.230 was injected, and chemical conversion was performed at a constant current of 10.4 A for 20 hours. The specific gravity of the electrolytic solution (sulfuric acid solution) after the formation was adjusted to 1.28 (20 ° C.). The clearance (width of the cell chamber X−thickness Y of the electrode plate group) was −0.8 mm, and the distance between the electrode plates was 0.75 mm.

  In the present example, the measurement of the width X of the cell chamber is ± 3 mm shorter than the boundary between the upper peripheral portion of the electrode plate located on the outermost side of the electrode plate group housed in the battery case and the electrode active material filling portion. This was done by measuring the width of the cell chamber in the direction. Further, the thickness Y of the electrode plate group was measured by the following method. First, the electrode plate group was taken out from the formed battery and washed with water for 1 hour, and the electrode plate group from which the electrolyte solution was removed was sufficiently dried in a system without oxygen. Next, a range r of ± 3 mm in the short direction from the boundary between the electrode active material filling portion of the negative electrode plate on the outermost side of the electrode plate group and the frame portion located on the ear portion side of the current collector included in the electrode plate The thickness of the electrode plate group is 3 points in total: 1 point at the center T1 in the longitudinal direction of the electrode plate group, 1 point at an arbitrary position T2 to the right of the center, and 1 point at an arbitrary position T3 to the left of the center. The average value of the measured values was defined as the thickness Y of the electrode plate group.

  The distance between the electrode plates was measured by the following method. First, the electrode plate group was taken out from the formed battery and washed with water for 1 hour, and the electrode plate group from which the electrolyte solution was removed was sufficiently dried in a system without oxygen. Subsequently, all the separators were extracted from the dried electrode plate group. For all the separators extracted, the separator is located at an area of about 8 mm from the upper end (the end on the ear side in the short direction) to the lower end (the end opposite to the ear side in the short direction). The thickness of the separator was measured, and the average value of the measured values was defined as the distance between the electrode plates. The thickness of the separator is measured on a total of three points on the two ribs arranged on the outermost side in the longitudinal direction and on the rib arranged on the midpoint among the plurality of formed ribs. The average value of the measured thickness was taken as the thickness of the separator.

<Example 2>
A lead storage battery was produced in the same manner as in Example 1 except that a lid having no exhaust chamber (non-double lid) was used instead of the lid having an exhaust chamber (double lid) as a lid. In addition, all the liquid injection ports (all liquid injection ports corresponding to the cell chambers) included in the lid having no exhaust chamber were plugged with liquid port plugs. In addition, the same explosion-proof filter as the double lid was used in the liquid stopper.

<Examples 3 to 6>
A lead-acid battery was produced in the same manner as in Example 1 except that graphite having a specific surface area shown in Table 1 was used as the carbon material instead of graphite having a specific surface area of 0.9 m ² / g.

<Examples 7 to 10>
Except having adjusted the compounding quantity of each component so that content (mass%) of sodium lignin sulfonate and carbon material on the basis of the total mass of the negative electrode active material after chemical conversion may become the value shown in Table 1, A lead storage battery was produced in the same manner as in Example 1.

<Comparative Example 1>
Example 1 was used except that a bisphenol-based resin (condensate of bisphenol, aminobenzenesulfonic acid and formaldehyde, trade name: Bispaz P215, manufactured by Nippon Paper Industries Co., Ltd.) was used instead of sodium lignin sulfonate. A lead-acid battery was produced.

<Comparative example 2>
A lead-acid battery was produced in the same manner as in Comparative Example 1 except that a lid having no exhaust chamber (non-double lid) was used instead of the lid having the exhaust chamber as the lid.

<Comparative Example 3>
As the carbon material, in place of the graphite having a specific surface area of 0.9 m ² / g, carbon black having a specific surface area of 240 m ² / g (furnace black, trade name: Vulcan XC72) for the use of, as well as the negative electrode active material after the chemical conversion In the same manner as in Example 1 except that the amount of each component was adjusted so that the content (% by mass) of sodium lignin sulfonate and the carbon material based on the total mass of the components became the values shown in Table 1. A lead-acid battery was produced.

<Comparative example 4>
A lead-acid battery was produced in the same manner as in Comparative Example 3 except that a lid having no exhaust chamber (non-double lid) was used instead of the lid having an exhaust chamber as the lid.

<Comparative Example 5>
As in Example 1, except that carbon black (acetylene black, trade name: Denka Black) having a specific surface area of 61 m ² / g was used as the carbon material instead of graphite having a specific surface area of 0.9 m ² / g. A lead-acid battery was produced.

<Comparative Example 6>
It replaced with the sodium lignin sulfonate and it carried out similarly to the comparative example 3 except having used the bisphenol-type resin (Condensate of a bisphenol, an aminobenzenesulfonic acid, and formaldehyde, brand name: Vispaz P215, Nippon Paper Industries Co., Ltd.). A lead-acid battery was produced.

<Comparative Example 7>
A lead-acid battery was produced in the same manner as in Comparative Example 6 except that a lid having no exhaust chamber (non-double lid) was used instead of the lid having an exhaust chamber as the lid.

<Characteristic evaluation>
Below, about the lead acid battery of an Example and a comparative example, DCA performance, lifetime performance (cycle characteristic), and the suppression effect of liquid reduction were evaluated. The results are shown in Table 1. The evaluation of each performance was performed by relative evaluation with the measurement result of Comparative Example 7 as 100.

(DCA performance)
DCA performance evaluation was performed by an evaluation method according to Dynamic Charge Acceptance (DCA) test described in BS EN 50342-6: 2015, which is an EN standard. The average current value during charging normalized by the conversion formula is compared, and it is evaluated that the larger the average current value, the better the DCA performance. The evaluation criteria are shown below.
A = 110 or more B = 100 or more and less than 110 C = less than 100

(Cycle characteristics (DOD 17.5% life test))
The DOD 17.5% life performance was measured as follows. First, a lead storage battery (discharge capacity: 60 Ah, 20 hour rate current: 3 A) that had been completely charged was placed in a water bath in which the bath temperature was set to 25 ° C. ± 2 ° C. Subsequently, the following cycle units (a) to (g) were set as one cycle, and repeated in the order of (a) to (g).
(A) The battery was discharged at 12 A (corresponding to 4 times the 20 hour current) for 2.5 hours. The discharge lower limit voltage was greater than 10.0V.
(B) The battery was charged with 21A (corresponding to 7 times the 20-hour current) for 40 minutes. The charge upper limit voltage was 14.4 ± 0.05V.
(C) The battery was discharged at 21 A (corresponding to 7 times the 20 hour current) for 30 minutes. The discharge lower limit voltage was greater than 10.0V.
(D) The above (b) and (c) were repeated 85 times alternately.
(E) The battery was charged with 6A (corresponding to twice the 20 hour current) for 18 hours. The charging method was CC (constant current) -CV (constant voltage) charging, and the voltage during CV charging was 16.0 V ± 0.05 V.
(F) The battery was discharged at 3 A (20 hour rate current ± 1.0%) until the discharge end voltage reached 10.5 ± 0.1 V, and the capacity of the lead storage battery was confirmed.
(G) The battery was charged for 24 hours at 15 A (5 times the 20-hour current). The charging method was CC-CV charging, and the voltage during CV charging was 16.0 V ± 0.05 V.
This test is a cycle test according to EN standards that simulates the use of lead-acid batteries in ISS cars. In this test, it was judged that the life was reached when the voltage of the lead storage battery fell below 10.0 V, and the cycle characteristics were evaluated by comparing the number of cycles until reaching the life. The evaluation criteria are shown below. The results are shown in Table 1.
A = 120 or more B = 110 or more and less than 120 C = less than 110

(Suppressing effect of liquid reduction)
The battery was overcharged at a constant voltage of 14.4 V for 42 days at an atmospheric temperature (water bath temperature) of 60 ° C. The weight before and after this charge was measured, and the weight difference (amount of liquid reduction due to overcharge (liquid reduction amount)) was compared. It is evaluated as having excellent inhibitory effect. The evaluation criteria are shown below.
A = 75 or less B = over 75 to 85 or less C = over 85

  DESCRIPTION OF SYMBOLS 1 ... Lead storage battery, 2 ... Battery case, 3 ... Cover, 4 ... 1st cover part, 5 ... 2nd cover part, 10 ... Electrode plate group (electrode group), 11 ... Negative electrode plate (negative electrode), 12 ... Positive plate (positive electrode), 22 ... cell chamber, 400 ... exhaust chamber constituent part, D1, D2, D3, D4, D5, D6 ... exhaust chamber, h ... reflux hole.

Claims (10)

A battery case having a cell chamber and having an open top surface;
An electrode group and an electrolyte contained in the cell chamber;
A lid that closes the opening;
The electrode group has a negative electrode and a positive electrode,
The negative electrode is a lead acid battery having a negative electrode active material containing a Pb component, lignin sulfonic acid and / or a salt thereof, and a carbon material having a specific surface area of 10.0 m ² / g or less.   2. The lead acid battery according to claim 1, wherein a content of the lignin sulfonic acid and a salt thereof is 0.05 to 0.5 mass% based on a total mass of the negative electrode active material.   The lead acid battery according to claim 1 or 2, wherein a content of the carbon material is 0.2 to 3.5 mass% based on a total mass of the negative electrode active material. The lid includes a first lid portion, a second lid portion provided on the first lid portion, and an exhaust formed between the first lid portion and the second lid portion. A chamber,
The reflux wall which recirculates the said electrolyte solution in a cell chamber is provided in the bottom wall of the said 1st cover part which separates between the said exhaust chamber and the said cell chamber. Lead-acid battery as described in a term. The lead acid battery according to any one of claims 1 to 4, wherein X and Y satisfy the following conditional expression when the width of the cell chamber is Xmm and the thickness of the electrode group is Ymm.
−1.1 ≦ X−Y ≦ 1.2   The lead acid battery according to any one of claims 1 to 5, wherein a distance between the adjacent negative electrode and the positive electrode is 0.4 to 0.8 mm. The lead acid battery according to any one of claims 1 to 6, wherein the carbon material has a specific surface area of 7.0 m ² / g or less. The lead acid battery according to claim 1, wherein the carbon material has a specific surface area of 1.0 m ² / g or less.   An idling stop system vehicle comprising the lead storage battery according to any one of claims 1 to 8. A micro hybrid vehicle comprising the lead storage battery according to any one of claims 1 to 8.

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