JP2011181322A - Lead accumulator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lead accumulator having a high capacity, as well as, a high vibration resistance. <P>SOLUTION: The lead accumulator includes a plurality of groups of polar plates made of polar plates of different polarity, which are alternately combined with separators disposed therebetween; a battery container having a plurality of cell chambers for housing the plurality of groups of polar plates; a connection body for collectively connecting the ear portions of the polar plates of the same polarity on both cell chamber sides; a lid; and an electrolyte, wherein the connection body includes an inter-cell connection portion (thickness t) for connecting the cell chambers that are adjacent to each other; a polar plate collector portion for collectively connecting the ear portions of the polar plates; and a bonding portion for bonding the inter-cell connection portion and the polar plate collector portion, wherein the bonding portion includes: a first bonding portion for bonding the underside of the inter-cell connection portion and the side of the polar plate collector portion; and a round-shaped second bonding portion (radius r) for bonding the side of the inter-cell connection portion and a top surface of the polar plate collector portion, and the relationship among t, r and total weight B (kg) per polar plate group 1 which is dried after being fully charged is represented by r/t/B>0.48 (kg<SP>-1</SP>). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a lead-acid battery.

  Lead-acid batteries are used in automobile cell starters, but with the recent spread of environmentally-friendly automobiles, lead-acid batteries installed in these automobiles have also become smaller, higher capacity, longer life and higher durability. Sex is required.

  A lead-acid battery is a battery case having a plurality of cell chambers in which a positive electrode and a negative electrode formed by filling a lead alloy paste with a lead-based paste are alternately combined via a separator to form a group of electrode plates. The electrode plate group is inserted, the electrode plate groups of adjacent cell chambers are connected in series, the upper part of the battery case is sealed with a lid, and then an electrolyte is injected. By not filling the part protruding from a part of the upper side of the lattice with paste, each of the positive electrode and the negative electrode is formed with a current collecting ear, and on one cell chamber side of the connection body provided in a shape straddling the cell chamber Adjacent cell chambers are connected in series by collectively connecting the ears of the positive electrode and collectively connecting the ears of the negative electrode to the other cell chamber side.

  A general connection body includes an inter-cell connection part that connects adjacent cell chambers, an electrode plate current collector part that collectively connects ears of electrode plates of the same polarity, an inter-cell connection part, and an electrode plate current collector part. It consists of the junction part which joins.

  As a method for connecting the electrode plate and the connection body, there are a cast-on method and a burning method. The caston method is a method in which molten lead is poured into a mold in which an electrode plate current collector and an inter-cell connection portion are integrated, and the electrode plate is immersed and cooled, and then molded. The burning method is a method in which the electrode plate current collector and the inter-cell connecting part are separately molded, and then the electrode plate ear part, the electrode plate current collecting part, and the inter-cell connecting part are welded. Regardless of which method is employed, the shape (mainly the connection shape) of the electrode plate current collector and the inter-cell connection portion affects the durability (particularly vibration resistance) of the lead storage battery.

  In the lead storage battery, the positive electrode undergoes volume expansion with repeated charging and discharging. This expansion may cause a load between the electrode plate current collectors and cause distortion between the connection portions between cells, and the connection body may be broken by applying vibration to the lead storage battery.

  Therefore, as in Patent Document 1, a configuration is conceivable in which the electrode plate current collector (electrode current collector in Patent Document 1) of the connection body can be bent upward in accordance with the volume expansion of the electrode plate. Specifically, there are those in which the thickness of the electrode plate current collector is devised as described as the first invention, and those in which the slits are provided in the inter-cell connection portions as described in the second invention. It has been.

Japanese Patent Laid-Open No. 02-094254

  However, although the structure of Patent Document 1 can eliminate the breakage of the connection body, the electrode plate is not provided because there is no electrode plate current collector immediately below the inter-cell connection part, that is, in the vicinity of the partition wall partitioning the cell chambers. It is assumed that they will not be placed. For this reason, it is impossible to increase the capacity by arranging a large number of electrode plates by effectively using the entire space of the cell chamber.

  This invention solves the subject mentioned above, and it aims at providing a high capacity | capacitance and high vibration resistance lead acid battery.

In order to solve the above-mentioned problem, the invention according to claim 1 is characterized in that a plurality of electrode plate groups in which electrode plates having different polarities are alternately combined via a separator, and a plurality of electrode plate groups that house the plurality of electrode plate groups. A lead-acid battery comprising a battery case having a cell chamber, a connecting body that collectively connects ears of electrode plates of the same polarity on both cell chamber sides, a lid, and an electrolyte solution. It consists of an inter-cell connecting part that connects the matching cell chambers, an electrode plate current collecting part that collectively connects the ears of the electrode plate, and a joint part that joins the inter-cell connecting part and the electrode plate current collecting part. Are a first joint that joins the bottom surface of the inter-cell connection portion and the side surface of the electrode plate current collector, and a side surface of the inter-cell connection portion and the top surface of the first joint portion and / or the electrode plate current collector portion. And a R-shaped second joint portion that joins to each other, and a thickness t of the inter-cell connecting portion and an R-shaped radius r of the second joint portion 6 Wherein the relationship between the total weight B (kg) of the electrode plate per one electrode group was dried after charging is r / t / B ≧ 0.48 ( kg -1).

  The invention described in claim 2 is characterized in that, in the invention described in claim 1, the connection body is constituted by a lead alloy which does not substantially contain antimony and contains tin.

  The connection body used for the lead storage battery of the present invention does not dispose the electrode plate current collector directly below the inter-cell connection part, and joins the bottom surface of the inter-cell connection part and the side surface of the electrode plate current collector by the first joint part. is doing. If this structure is adopted, an electrode plate can be arranged directly below the inter-cell connection part, and the ears of the electrode plate can be collectively connected to the electrode plate current collector. That is, since a larger number of electrode plates can be arranged as compared with Patent Document 1, it is possible to increase the capacity.

  In addition, the lead storage battery of the present invention can exhibit the same level of vibration resistance as that of Patent Document 1 due to the synergistic effect of the following two characteristics.

  The first feature is that an R-shaped second joint that joins the side surface of the inter-cell connecting portion and the upper surface of the first joint and / or the electrode plate current collector is provided. This is to optimize the relationship between the radius r and the thickness t of the connection part between cells. In order to improve the vibration resistance, it is necessary to increase the fatigue strength by lowering the maximum stress value applied to each member. When a cyclic load of vibration is applied, even ductile materials such as lead do not show much plastic deformation, and depending on the shape of the member, the maximum stress applied increases, so local cracks occur due to vibration, and this crack is Breaks as the starting point. In order to avoid this problem, it is necessary to make the structure of the connection body made of the lead alloy difficult to cause local cracks. As a result of intensive studies by the present inventors, not only randomly providing R-shaped second joints, but also increasing the radius r to increase the ratio r / t to the thickness t of the inter-cell connection part. It has been found that a slight increase in weight makes it difficult for local cracks to occur in the connection body and improves the fatigue strength. The first feature utilizes this knowledge, and the whole connected body has a shape capable of suppressing local cracks, while the electrode plate current collector is strong against a constant load (plastic region). However, the material characteristics of lead are utilized, and the electrode plate has a shape that can be plastically deformed with respect to the volume expansion (load of a constant load) of the electrode plate. However, the presence or absence of the effect of the present invention in an actual lead storage battery is affected by the total weight of the electrode plates hanging from the electrode plate current collector.

  The second feature is that the electrode plate group is connected to the cell by connecting the ears of the electrode plate along all the long sides of the electrode plate current collector (with the electrode plate arranged immediately below the inter-cell connecting portion). It is easier to touch the partition that separates the rooms. In order to increase the capacity, the electrode plate is also arranged directly below the inter-cell connection part, and when the electrode plate group and the partition have a predetermined friction coefficient, compared to a case where there is a sufficient gap between them, Since the vibration of the electrode plate group itself due to the propagation of the vibration wave is less likely to occur, the stress applied to the connection body is reduced.

  The present invention is particularly effective when a connection body is composed of a lead alloy (Pb-Sn) containing substantially no antimony and containing tin for the purpose of improving the corrosion resistance. High capacity lead-acid batteries can be realized.

  As described above, according to the present invention, since the electrode plate can be arranged directly below the inter-cell connection portion, the capacity can be increased, and the high vibration resistance can be secured together with the structure of the second joint portion. A lead storage battery can be provided.

(A) Partial perspective view showing the characteristic part of the lead storage battery of the present invention, (b) Cross sectional view along A plane, (c) Cross sectional view along B plane, (d) Cross sectional view along C plane (A) The figure which shows the result of having simulated the relationship between ratio r / t of the radius r of a 2nd junction part, and the thickness t of the connection part between cells, and the maximum stress value concerning a connection body, (b) 1st The figure which shows the result of having simulated the relationship between the length s which a junction part contacts an electrode plate current collection part, and the maximum stress value concerning a connection body, (c) The thickness t of the connection part between cells, and the maximum stress value concerning a connection body That shows the result of simulating the relationship The figure which shows the result of having evaluated the relationship between the ratio r / t of the radius r of the 2nd junction part, and the thickness t of the connection part between cells, and vibration resistance with the actual lead acid battery. (A) In the D23 size, the result of FIG. 3 is added to the result of FIG. 3, and (b) In the D26 size, the effect of the total weight B of the electrode plate is added to the result of FIG. Summary figure The figure which expanded the principal part of FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 shows a characteristic part of the lead-acid battery of the present invention, where (a) is a partial perspective view, (b) is a cross-sectional view along the A plane shown in (a), and (c) is (a). (D) is sectional drawing along the C surface shown to (a). A plurality of electrode plate groups in which electrode plates 1 (positive electrode and negative electrode) having different polarities are alternately combined via separators (not shown) are housed in a plurality of cell chambers of a battery case (not shown), The lead storage battery of the present invention is configured by electrically connecting each other with the connecting body 7 having a shape straddling the cell chamber, providing a lid at the opening of the battery case, and injecting the electrolyte into each cell chamber. The

  The connection body 7 includes an inter-cell connection portion 4 that connects adjacent cell chambers, an electrode plate current collector 3 that collectively connects the ear portions 2 of the electrode plate 1, an inter-cell connection portion 4, and an electrode plate current collector 3. Are joined together (indicated by hatching in FIGS. 1B to 1D). In a general lead-acid battery, the connection body 7 is connected to the electrode plate current collector 3 on one cell chamber side, and is connected to the electrode ear 2 of the positive electrode, and the electrode plate current collector on the other cell chamber side. What is collectively connected to the portion 3 is the ear 2 of the negative electrode. By making such a connection, the lead storage battery is connected in series by the amount corresponding to the cell chamber.

  The connection body 7 includes a first joint 5 that joins the bottom surface of the inter-cell connection portion 4 and the side surface of the electrode plate current collector 3, a side surface of the inter-cell connection portion 4, the first joint portion 5, and / or It is composed of an R-shaped second joint 6 that joins the upper surface of the electrode plate current collector 3, and optimizes the relationship between the radius r of the second joint 6 and the thickness t of the inter-cell connection 4. It is characterized by that. In order to improve the vibration resistance, it is necessary to increase the fatigue strength by reducing the maximum stress value applied to each member. However, when a repeated load of vibration is applied, ductile materials such as lead do not show large plastic deformation. Depending on the shape of the connection body 7, the maximum stress value to be applied becomes high, so that a local crack is generated along with the vibration, and the fracture starts from this crack. In order to avoid this problem, it is necessary to make the structure of the connection body 7 made of a lead alloy difficult to cause local cracks. By increasing the radius r of the second joint 6 and increasing the ratio r / t to the thickness t of the inter-cell connection portion, the connection body 7 is less likely to cause local cracks with a slight increase in weight. (Maximum stress value decreases and fatigue strength improves). In the present invention, this knowledge is utilized, and the connection body 7 as a whole can suppress local cracks, while the electrode plate current collector 3 is a lead that is strong against a load of a constant load (wide plastic region). Thus, the shape of the electrode plate 1 can be sufficiently plastically deformed with respect to the volume expansion (constant load). In particular, as shown in FIGS. 1B and 1C, by providing the second connection portion 6 so as to protrude from both the A surface and the B surface of the inter-cell connection portion 4, the effect of the present invention is further improved. Can be increased. However, the presence or absence of the effect of the present invention in an actual lead-acid battery is affected by the total weight of the electrode plate 1 depending from the electrode plate current collector 3 as will be described in detail later.

  In addition, the connecting body 7 does not arrange the electrode plate current collector 3 immediately below the inter-cell connection portion 4, and the first joint portion 5 joins the bottom surface of the inter-cell connection portion 4 and the side surface of the electrode plate current collector portion 3. is doing. If this structure is adopted, the electrode plate 1 can be arranged immediately below the inter-cell connection portion 4 and the ear portion 2 of the electrode plate 1 can be collectively connected to the electrode plate current collecting portion 3. That is, since a larger number of electrode plates 1 can be arranged as compared with Patent Document 1, it is possible to increase the capacity. By adopting this configuration, the electrode plate group can easily come into contact with partition walls (not shown) that partition the cell chambers. When the electrode plate group and the partition wall have a predetermined coefficient of friction, vibration of the electrode plate group due to propagation of the vibration wave is less likely to occur than when there is a sufficient gap between them. Accordingly, the stress applied to the connection body 7 is reduced.

  Due to the synergistic effect of the above two features, the lead storage battery of the present invention can exhibit the same level of vibration resistance as that of Patent Document 1.

  In the positive electrode of the present invention, lead powder can be used for the active material, and a Pb—Ca—Sn alloy can be used for the lattice filled with the active material and additives.

  In the negative electrode of the present invention, lead powder can be used for the active material, carbon, barium sulfate, and lignin compound can be used for the additive, and Pb—Ca— can be used for the lattice filled with the active material and additive. Sn alloy can be used.

  A resin such as polyethylene can be used for the separator of the present invention.

  Resin such as polypropylene can be used for the battery case and the lid of the present invention.

  For the electrolytic solution of the present invention, sulfuric acid having a specific gravity of 1.25 to 1.30 can be used.

  Various lead alloys can be used for the connection body 7 of the present invention. If the connection body 7 is made of a lead alloy (Pb-Sn) that does not substantially contain antimony and contains tin in order to improve corrosion resistance, a high-capacity lead-acid battery that is excellent in both corrosion resistance and vibration resistance is realized. become able to.

  Next, the effects of the present invention will be described with reference to examples.

(simulation)
A simulation performed prior to a test using an actual lead storage battery will be described.

  FIG. 2 is a diagram showing the result of simulating the relationship between the various shapes of the connection body 7 and the maximum stress value applied to the connection body 7, wherein (a) shows the radius r of the second joint 6 and the connection between cells. The ratio to the thickness t of the portion 4, (b) is the length S at which the first joint 5 is in contact with the electrode plate current collector 3, and (c) is the result of examining the thickness t of the inter-cell connecting portion 4. is there. The simulation was performed using a finite element method with a setting that applies a load in the vertical direction only to the connection body 7.

In FIG. 2, as a measure of the maximum stress value, the maximum stress value (σ _MAX ) applied to the connection body 7 in which r, t, and S are arbitrarily changed is represented by standard conditions, that is, r = 2, t = 4, L = 40 (where L is the length of the electrode plate current collector 3), ratio divided by the maximum stress value (σ _S ) applied to the connection body 7 at r / t = 0.5, S / L = 0.55 (Σ _max / σ _s ) was used. That is, it can be said that the smaller the ratio σ _max / σ _s is, the better the connection body 7 is designed to have vibration resistance.

  In FIG. 2, a ratio obtained by dividing the weight of the connection body 7 in which r, t, and S are arbitrarily changed by the weight of the connection body 7 under the standard conditions is used as a scale for increasing or decreasing the weight.

  From FIG. 2A, if the radius r of the second joint portion 6 is increased with respect to the thickness t of the inter-cell connection portion 4, the maximum stress value of the connection body 7 is greatly increased despite a slight increase in weight. Can be reduced. On the other hand, even if the length S at which the first joint 5 is in contact with the electrode plate current collector 3 is increased as shown in FIG. Although the weight of 7 is increased, the maximum stress value is not reduced. Further, when the thickness of the inter-cell connection portion 4 is increased as shown in FIG. 2C, the connection body 7 is accompanied by a significant increase in weight although the maximum stress value is reduced. From the results of these simulations, it was found that optimizing the ratio of the radius r of the second joint 6 and the thickness t of the inter-cell connection 4 is more effective than the examination of other parts. .

  Therefore, in order to verify the simulation results described above, an actual lead storage battery was constructed and a vibration resistance test was performed.

(Test with actual lead-acid battery)
The positive electrode was produced by filling a lattice made of a lead alloy (Pb—Ca—Sn) with a paste made of lead powder. The negative electrode was prepared by filling a lattice made of a lead alloy (Pb—Ca—Sn) with a paste made of lead, carbon, barium sulfate and a lignin compound. The positive electrode and the negative electrode were alternately combined through a polyethylene separator to produce a plurality of electrode plate groups, which were inserted into a polypropylene battery case having a plurality of cell chambers.

  As the connection body 7, a lead alloy (Pb-Sn) containing substantially no antimony and containing tin is used. As shown in FIG. 1, the electrode plate current collector 3, the inter-cell connection 4, the first joint 5 and A structure including the second joint portion 6 was adopted. At that time, the thickness t of the inter-cell connecting portion 4 was kept constant at 4 mm, and the radius r of the second joint portion 6 was variously changed. Then, the electrode plate current collector 3 is collectively welded to the ear portion 2 of the electrode plate 1 of the same polarity, and a plurality of electrode plate groups are connected in series by connecting the inter-cell connection portions 4 of the adjacent cell chambers. After sealing the opening of the battery case with a lid made of polypropylene, sulfuric acid having a specific gravity of 1.28 is injected as an electrolyte, so that D23 size (total weight B of electrode plate B = 1.540 kg) and D26 in JIS D5301 A lead-acid battery having a size (total weight B of electrode plate 1 = 1.85 kg) was produced.

A plurality of lead storage batteries were prepared for each design condition of the connection body 7 described above, and subjected to a vibration resistance test by the method shown in JIS D5301. Specifically, while gradually increasing the vibration acceleration applied to the lead-acid battery until reaching a vibration acceleration of 49.0 (m / s ² ) exceeding the Japanese Industrial Standard value (vibration acceleration of 29.4 (m / s ² )), The vibration acceleration when the first one becomes impossible to discharge, and the ratio (defective rate) of the number of lead-acid batteries that became unable to discharge before reaching the vibration acceleration of 49.0 (m / s ² ). Recorded. For all lead-acid batteries satisfying the vibration resistance of 49.0 (m / s ² ), the vibration acceleration is further increased until the first one cannot be discharged in order to obtain the limit value of vibration acceleration. Increased.

The test results obtained in this manner are plotted with the vibration acceleration (measurement of vibration resistance) and the defect rate (vibration acceleration 49.0 (m / s ² ) when the first one cannot be discharged on the vertical axis. The ratio of the number of lead-acid batteries that have become incapable of discharging before reaching ()), the horizontal axis is summarized as the ratio r / t based on the knowledge obtained by simulation, and is shown in FIG.

In both sizes, the vibration resistance is improved at a predetermined ratio r / t (the rate at which discharge is impossible before reaching 49.0 (m / s ² ) is drastically reduced), but the predetermined ratio r / t The D26 size was 1 but the D23 size was 0.8.

  On the basis of the test results obtained there, the horizontal axis represents a value (r / t / B) obtained by further dividing the ratio r / t by the total weight B of the electrode plate 1 suspended from the electrode plate current collector 3. This is shown in (a) (D23 size), FIG. 4 (b) (D26 size) and FIG.

  As can be seen from FIGS. 4A and 4B and FIG. 5, the actual lead storage battery configuration conditions (the total weight B of the electrode plate 1 hanging from the electrode plate current collector 3) are based on the knowledge of the simulation considering only the connection body 7. ), It can be seen that the vibration resistance is improved with the same ratio r / t / B as the boundary even if the size of the lead-acid battery is different.

  In the lead storage battery of the present invention, the ear plate 2 of the electrode plate 1 is connected along all the long sides of the electrode plate current collector 3, so that the electrode plate group and the partition wall that partitions the cell chambers have a predetermined coefficient of friction. To have. By adopting this configuration, the vibration of the electrode group due to the propagation of the vibration wave is less likely to occur in the vibration resistance test. Therefore, although the stress applied to the connection body 7 is reduced, the electrode plate is proportional to the weight of the electrode group. The group vibration becomes large. That is, the configuration showing the effect referred to by the present invention is the one having a ratio r / t / B exceeding 0.48, which is indicated by a circle in FIGS. 4 (a) and 4 (b) and FIG.

In the comparative example (indicated by x in FIGS. 4 (a), 4 (b) and 5) where the ratio r / t / B is 0.48 or less, it is impossible to discharge until reaching 49.0 (m / s ² ). When the lead storage battery became disassembled after the test, the boundary (first joint 5 or second joint 6) between the electrode plate current collector 3 and the inter-cell connection 4 was all broken. On the other hand, among the examples in which the ratio R / t / B exceeds 0.48, a lead-acid battery that cannot be discharged in a vibration resistance test exceeding 49.0 (m / s ² ) is disassembled after the test. As a result, the ears 2 of the electrode plate 1 were all broken. That is, the fact that the vibration resistance of the lead-acid battery of the example has peaked near the vibration acceleration 58 (m / s ² ) is not due to the fracture of the connection body 7 itself.

When a breakage occurs at a place where the electrolytic solution is not immersed, a spark may occur due to an internal short circuit and the battery case may be damaged. Lead-acid battery of the present invention not only shows the vibration resistance satisfying 49.0 (m / s ^2), take place the vibration exceeding Should 49.0 (m / s ^2), the user is minimum fluid Since the ear part 2 of the electrode plate 1 is immersed in the electrolytic solution as long as the surface line is managed, no spark is generated. Therefore, a portion that is not immersed in the electrolytic solution even if this management is performed (the electrode collector part 3 Unlike the comparative example that breaks at the boundary of the inter-cell connecting portion 4), the configuration is a fail-safe.

Further, in all of the lead storage batteries of the examples, those that could not be discharged in the vibration resistance test exceeding 49.0 (m / s ² ) had the lug 2 of the positive electrode broken. The effect of oxidation (partially lead dioxide) and easy breakage due to vibration is also conceivable, but considering the influence of the weight of the electrode plate 1 (positive electrode> negative electrode), the knowledge of the simulation ( It can be said that the result shows the validity of dividing (ratio / t) by the total weight B of the electrode plate 1 (ratio / t / B).

  Note that the “total weight B of the electrode plate 1” in the present invention is that after fully charged under the conditions specified in JIS D5301, the lead-acid battery is disassembled, the electrode plate 1 is taken out, the electrolyte is washed away and dried. It was determined from the later weight. Since the weight of the electrode plate 1 fluctuates due to the variation in the charging depth of the lead storage battery, it is necessary to define the weight of the electrode plate 1 by the method described above.

  Since the lead storage battery of the present invention is excellent in vibration resistance, it is preferable as an in-vehicle cell starter and a driving power source that are susceptible to vibration, and its applicability is extremely high.

DESCRIPTION OF SYMBOLS 1 Electrode plate 2 Ear part 3 Electrode plate current collection part 4 Inter-cell connection part 5 1st junction part 6 2nd junction part 7 Connection body

Claims (2)

A plurality of electrode plate groups in which electrode plates of different polarities are alternately combined via a separator, a battery case having a plurality of cell chambers for storing the plurality of electrode plate groups, and one cell chamber side having one polarity A lead-acid battery comprising a connecting body for collectively connecting the ears of the other polarity electrode plate on the other cell chamber side while collectively connecting the ears of the electrode plate, a lid, and an electrolyte solution,
The connection body includes an inter-cell connecting portion that connects adjacent cell chambers, an electrode plate current collecting portion that collectively connects ear portions of the electrode plates, and an inter-cell connecting portion and the electrode plate current collecting portion. Consisting of joints to be joined,
The joint includes a first joint that joins a bottom surface of the inter-cell connection portion and a side surface of the electrode plate current collector, a side surface of the inter-cell connection portion, the first joint portion, and / or the It comprises an R-shaped second joint that joins the upper surface of the electrode plate current collector,
A thickness t of the inter-cell connecting portion, an R-shaped radius r of the second joint 6, and a total weight B (kg) of the electrode plates per one electrode plate group dried after full charge The relationship is r / t / B> 0.48 (kg ⁻¹ ). 2. The lead acid battery according to claim 1, wherein the connecting body is made of a lead alloy substantially free of antimony and containing tin.

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