WO2008105559A1

WO2008105559A1 - Lead storage battery

Info

Publication number: WO2008105559A1
Application number: PCT/JP2008/053893
Authority: WO
Inventors: Kyoko Honbo; Yasuo Kondo; Masanori Sakai; Tokiyoshi Hirasawa
Original assignee: Shin-Kobe Electric Machinery Co., Ltd.
Priority date: 2007-02-27
Filing date: 2008-02-27
Publication date: 2008-09-04
Also published as: JP5087950B2; JP2008210698A

Abstract

This invention provides a lead storage battery which has a prolonged deep discharge cycle service life, has good recovery charge properties, and can suppress corrosion elongation to reduce a possibility of shortcircuiting. The lead storage battery comprises a positive electrode lattice. The positive electrode lattice comprises a base material composed mainly of a Pb-Ca-Sn alloy and a surface layer formed by powder-rolling a rapidly cooled solidified powder of a Pb-Sn alloy having a lower Sn content than the content of Sn contained in the base material, or a surface layer formed by powder-rolling a rapidly cooled solidified powder of high-purity lead.

Description

Lead-acid battery All publications, patents and patent applications cited in this specification are incorporated herein by reference in their entirety. Technical field

Light

The present invention relates to a lead storage battery, and more particularly to a lattice structure used for a positive electrode and a negative electrode of a lead storage battery.

Background art

The positive electrode and the negative electrode of the lead storage battery have a lattice body and an active material filling it. Patent Document 1 describes a lattice formed by punching a sheet. This sheet has a lead-calcium alloy as a base material, a lead-silver alloy layer formed on one surface of the base material, and a lead-tin alloy layer formed on the other surface. In this example, the silver content in the lead-silver alloy is 0.01 to 2.0%, and the tin content is 0 to 10%. The content of tin in lead-tin alloy is 1-30%. In lead-acid batteries using this grid, even when left at high temperatures, corrosion of the grid is suppressed, and the corroded oxide layer becomes active and maintains adhesion with the active material. -Patent Document 2 describes the use of a plate piece integrated with a lead-calcium alloy plate and a lead-tin alloy plate as an electrode substrate. Patent Document 3 describes a method in which a lead-calcium-0.3% tin alloy sheet is sandwiched between 0.5 mm-thick lead 1-3% tin alloy and rolled, and an integrated alloy plate is used for the lattice. ing. Patent Document 4 discloses a method in which a rolled plate in which a lead-tin-tin-based alloy layer containing 1.8% or more of tin is bonded to the surface of a lead-calcium-tin-based alloy containing 1.6% or less of tin is used as a lattice body. Is described.

In these examples, the recoverability after being left for a long period of time or being left overdischarged is improved, and the life under high temperature use can be extended. Patent Document 5 describes that a lattice obtained by processing a rolled sheet made of pure lead containing no antimony is used in order to reduce lattice corrosion and obtain a battery having a longer life. The width of this grid is more than 1.2 times the sheet thickness.

Furthermore, Patent Document 6 describes a method using a lattice body having a thin layer of high-purity lead metal rolled and integrated on the surface, and Patent Document 7 describes a lead-tin system on the surface of a pure lead plate. A method for integrating the alloy layer is disclosed. In either case, high purity lead (99.9% or more) can avoid the passivation of the lattice and provide excellent life characteristics.

Patent Document 8 shows that a lattice body in which a lead-containing core member is covered with a Pb sheet having an average crystal grain size of at least 100 micrometers exhibits good erosion resistance in a battery atmosphere. ing.

Patent Document 1: Japanese Patent Application Laid-Open No. 6 3-2 1 1 567

Patent Document 2: JP-A-1-140557

Patent Document 3: Japanese Unexamined Patent Publication No. 2000-195524

Patent Document 4: JP-A-61-124064 (Japanese Patent Publication No. 4 1 8 1307) Patent Document 5: JP-A-2004-14431

Patent Document 6: Japanese Unexamined Patent Application Publication No. 2004-1 525 78

Patent Document 7: Japanese Unexamined Patent Publication No. 2003-208898

Patent Document 8: Japanese Patent Laid-Open No. 10-276 16 Disclosure of Invention

In recent automobiles, power consumption has increased with the electrification of hydraulic drive systems such as power steering and brakes. For this reason, automotive power supplies are required to have durability against deep discharge cycles. In lead-acid batteries, when a deep discharge cycle is repeated, a passive layer of lead sulfate, that is, an insulating layer, is formed on the current collector interface. When this happens, it is known that early capacity loss occurs and life is reached. In addition, it is known that if a lead-acid battery is left in an overdischarged state at a high temperature, if the tin content of the current collector is low or pure lead, the interface corrodes and the recovery chargeability decreases. It has been.

On the other hand, lead-acid battery UPS (standby use) is performed in automobiles. This is a usage method in which the state of charge always remains. Navigation picture mounted on a car To prevent the surface from flickering, measures to prevent overdischarge on the system side, for example, frequent charging may be performed. This method of use advances the lattice corrosion of the positive electrode and shortens the battery life. In addition, problems such as the danger of short-circuiting due to corrosion elongation have been pointed out.

In addition, as one of the measures to improve the fuel efficiency of automobiles, lighter power sources are required. In lead-acid batteries, in order to avoid the problem of grid corrosion of the positive electrode, a grid with a thick grid has been used. On the other hand, the expanded lattice formed by expanding the rolled sheet and the punched lattice formed by punching the rolled sheet have the advantage that the thickness of the lattice is thin and the weight can be reduced. is there. However, the expanded lattice and the punched lattice have the disadvantage that the active material layer is easily peeled off due to poor adhesion to the active material. Therefore, the deep discharge cycle life is short. In addition, since the rolled sheet has a fine lamellar structure, unlike a forged grid in which intergranular corrosion mainly proceeds, the corroded layer tends to peel off in layers. Therefore, the apparent expansion rate is high, and short-circuiting due to corrosion elongation is likely to occur.

If pure lead is used in the grid, passivation can be avoided and the life characteristics can be improved, but pure lead has the disadvantage of low strength. Therefore, if an active material is filled in an expanded lattice or a punched lattice of pure lead, it will not be deformed into a fixed shape electrode. Therefore, a structure in which a strong lead-calcium alloy is used as a base material and a thin sheet of pure lead is attached to the surface is also conceivable. However, if rolling is performed with a thin plate of pure lead having a low strength on the base material, the pure lead is more easily stretched than the base material, and the two cannot be bonded together.

Conversely, a structure in which pure lead is used as a base material and a lead-tin alloy layer is laminated on the surface is also conceivable. However, since pure lead with low strength is the base material, sufficient strength cannot be obtained as the positive electrode grid.

As described above, it is desirable that the positive electrode grid for a lead storage battery suppresses an early capacity drop and extends the life of the lead storage battery even if the deep discharge cycle is repeated. Furthermore, it is necessary that the recovery chargeability does not deteriorate even when left in an overdischarged state at a high temperature. Also in the usage method where the charged state continues, it is desirable to suppress the lattice corrosion and extend the battery life, and to suppress the corrosion elongation and reduce the risk of short circuit. Furthermore, in expanded and punched grids, it is necessary that the adhesion with the active material is improved and the deep discharge cycle life is long, and the risk of short-circuiting can be reduced by suppressing the corrosion elongation. Further, it is desirable that sufficient battery characteristics can be obtained even if the amount of expensive tin or silver added is small. In terms of manufacturing, even if pure lead rolled sheet is used, it has excellent handling properties, can be easily integrated with the surface of lead-calcium alloy by rolling, has no cracks due to corrosion, and has a long life. Is desirable.

The object of the present invention is that the deep discharge cycle life is long, the recovery chargeability is good, the corrosion elongation is suppressed and the risk of short-circuiting can be reduced, and the battery characteristics are sufficient even if the addition amount of expensive tin or silver is small Is to provide a lead storage battery and a positive electrode grid for a lead storage battery. The positive electrode lattice body of the lead storage battery of the present invention includes a base material mainly containing a Pb_Ca-Sn alloy and a Pb-Sn alloy containing Sn having a lower content than Sn contained in the base material. A surface layer obtained by powder rolling of a rapidly solidified powder of, or a surface layer obtained by powder rolling of a rapidly solidified powder of high purity lead.

The surface layer has crystal grains oriented in a specific direction with an aspect ratio of 3 to 13, and may contain at least one of B i, A g, B a, S r and A 1.

According to the present invention, the deep discharge cycle life is long, the recovery chargeability is good, the corrosion elongation is suppressed, the risk of short circuit can be reduced, and sufficient battery characteristics can be obtained even if the amount of expensive tin or silver added is small. Provided lead acid battery and positive electrode grid for lead acid battery can be provided

Brief Description of Drawings

FIG. 1 is a diagram showing a configuration of a single plate lead-acid battery incorporating a positive electrode grid according to the present invention.

FIG. 2 is a diagram showing the configuration of the positive electrode grid according to the present invention.

FIG. 3 is a view showing a cross-sectional structure of the rapidly solidified powder used for producing a rolled sheet used in the positive electrode grid according to the present invention.

FIG. 4 is an explanatory diagram of a process for producing a rolled sheet used in the positive electrode grid according to the present invention.

FIG. 5 is an explanatory diagram of a process for producing a rolled sheet used in the positive electrode grid according to the present invention. It is.

FIG. 6 is a view for explaining the configuration of the cross section of the surface layer of the rolled sheet used in the positive electrode grid according to the present invention.

FIG. 7 is a structural cross-sectional photograph of the surface layer of the rolled sheet used in the positive electrode grid according to the present invention.

FIG. 8 is a diagram for explaining an experiment for measuring the tensile strength of a rolled sheet used in the positive electrode grid according to the present invention.

FIG. 9 is a diagram for evaluating the adhesion of the surface layer to the substrate of the rolled sheet used in the positive electrode grid according to the present invention.

FIG. 10 is a view showing the corrosion amount evaluation results of the rolled sheet used in the positive electrode grid according to the present invention. .

FIG. 11 is a diagram showing the results of a deep discharge cycle test of a rolled sheet used in the positive electrode grid according to the present invention.

FIG. 12 is a partially cut perspective view for explaining the configuration of a lead-acid battery for automobiles incorporating a positive electrode grid according to the present invention.

FIG. 13 is a partially cut perspective view for explaining the configuration of a wound lead-acid battery incorporating the positive electrode grid according to the present invention.

FIG. 14 is a partially cut perspective view for explaining the configuration of a control valve type lead-acid battery incorporating a positive electrode grid according to the present invention.

FIG. 15 is a diagram showing the deep discharge cycle characteristics of Example 1 of the positive electrode grid according to the present invention and the single plate lead-acid battery using the same.

FIG. 16 is a diagram showing the deep discharge cycle characteristics of Example 2 of the positive electrode grid according to the present invention and the single plate lead-acid battery using the same.

FIG. 17 is a diagram showing the deep discharge cycle characteristics of Example 3 of the positive electrode grid according to the present invention and the single plate lead-acid battery using the same.

FIG. 18 is a diagram showing the deep discharge cycle characteristics of Example 4 of the positive electrode grid according to the present invention and the single plate lead-acid battery using the same. Explanation of symbols 1 ... Positive electrode plate, 2 ... Negative electrode plate, 3 ... Separator, 4 ... Positive electrode active material, 5 ... Positive electrode active material, 6 ... Negative active material, 7 ... Negative electrode active material, 8 ... Positive electrode ear, 9 ... Negative electrode ear, 10 ... Substrate, 11 ... Surface layer, 14, 15 ... Cross-section of rapidly solidified powder, 16, 17 ... Crystal grains of rapidly solidified powder, 18 ... Hotsuba, 19 ... Quick solidified powder, 20 ... Powder rolling roll, 21 ... Powder rolling sheet, 22… Base rolling sheet, 23… Rolling roll, 24 ··· Rolling sheet, 25——Stage rolling roll, 26… Formed plate, 27… Rolling direction, 28, 29, 30 ··· Surface Cross section of layer, 36 ... Positive electrode plate, 37 ... Negative electrode plate, 38 ... Separator, 39 ... Laminated plate group, 40 ... Battery case, 41 ... Positive electrode ear, 42 ... Lid, 43 ··· Positive terminal, 44 ··· Negative electrode terminal, 45 ··· Retainer, 46 ··· Winding electrode plate group

Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings as appropriate. First, as an example of the present invention, a single plate lead-acid battery having a simple structure and a positive electrode grid body incorporated therein will be described. In the drawings to be referred to, FIG. 1 is a configuration explanatory view of a single plate lead-acid battery in which a positive electrode lattice body according to this embodiment is incorporated.

As shown in FIG. 1, the single plate lead-acid battery of this example has a positive electrode plate 1, a negative electrode plate 2, and a separator 3, and these members are electrolyses containing sulfuric acid (H ₂ S 0 ₄ ). Impregnated with liquid (not shown). The positive electrode plate 1 has a positive electrode active material 4 that fills the gap between the positive electrode grid body 5 and the positive electrode grid body 5. Similarly, the negative electrode plate 2 fills the gap between the negative electrode grid body 7 and the negative electrode grid body 7. It has a negative electrode active material 6. A positive electrode ear 8 is connected to the positive electrode plate 1, and a negative electrode ear 9 is connected to the negative electrode plate 1. The positive electrode ear 8 and the negative electrode ear 9 are connected to terminals for connection to a load.

The positive electrode grid 5 is formed into a mesh body by machining. For example, it can be obtained by punching a rolled sheet or by an expanding process in which a rolled sheet is cut and stretched. .

The positive electrode active material 4 may be a known material, and after the positive electrode active material paste containing lead powder, red lead, lead sulfate, basic lead sulfate, additives, etc. is filled in the current collector of the positive electrode grid 5 This can be obtained by drying. As is well known, the positive electrode active material 4 in contact with the current collector of the positive electrode grid 5 is converted to lead dioxide (PbO ₂ ) by chemical conversion. FIG. 2 shows an example of a rolled sheet used for preparing the positive electrode grid 5 of the present invention. The rolled sheet of this example includes a base material 10 and a surface layer 11 thereon, which are integrated. The thickness of the surface layer 11 is preferably thinner than the thickness of the substrate 10.

The substrate 10 is mainly composed of a P b—C a—S n alloy. According to the present invention, the surface layer 11 is a thin film of a Pb—Sn alloy containing Sn with a lower content than Sn contained in the base material 10. The Pb—Sn alloy of the surface layer 11 preferably contains at least one of Bi, Ag, Ba, Sr, and A1. By adding these elements, various properties such as corrosion resistance and adhesion are improved. This will be explained later.

Usually, tin diffuses easily in lead metal. When a positive electrode grid is produced using only the base material 10, a high-content tin layer is formed at the interface between the active material and the current collector of the positive electrode grid. Tin layer of high content of this conductive high, because rich in charging properties, the periphery of the lead is easily oxidized by / 3 becomes a P b 0 _2. ) 3 in P b 0 ₂ deep discharge cycles, sulfated lead content at a very early stage, to form a passivation layer. That is, the deep discharge cycle life is shortened. According to the present invention, the current collector / active material interface of the positive grid is formed by the contact interface between the surface layer 11 on the substrate and the active material. The surface layer 11 is formed by thinning a Pb—Sn alloy containing Sn having a lower content than Sn contained in the base material. Therefore, the tin content contained in the tin layer formed at the interface between the current collector and the active material is lower than that of the prior art. This tin layer has low conductivity because of its low tin content. Therefore, the periphery of the lead,) 3- P b 0 ₂ does not change. Accordingly, it is desirable that the tin content in the surface layer 11 of the rolled sheet that extends the cycle life of the deep discharge is O.lw t% or more and less than l.Ow t%. The content of tin in the range, a remarkable effect can be suppressed around the lead] to oxidation to 3 _ P b O _2.

According to this example, the tin content of the surface layer 11 is lower than the tin content of the base material. Therefore, tin diffuses from the substrate to the surface layer. Therefore, the greater the thickness Y of the surface layer, the greater the amount of tin that enters the surface layer from the substrate. That is, when the thickness Y of the surface layer is increased, the tin content in the base material decreases. As the tin content in the substrate decreases, the corrosion elongation increases and the risk of a short circuit increases. Therefore, the surface layer thickness Y is too large. I can't speak. On the contrary, when the thickness Y of the surface layer is small, tin enters the surface layer from the base material, so that the tin content in the surface layer increases. As a result, the effect of the surface layer on the battery characteristics, in particular, the extension of the deep discharge cycle life cannot be obtained.

The thickness of the substrate 10 is X, and the thickness of the surface layer 11 is Y. The ratio of the thickness Y of the surface layer to the thickness X of the substrate, that is, Y: X is preferably in the range of 1:10 to 1:60. For this, refer to the description of Example 2 shown in FIG. 16 later.

According to the present invention, since the base material uses a Pb—C a —Sn alloy having high mechanical strength, the strength of the positive electrode lattice can be ensured. On the other hand, since the surface layer uses a Pb—Sn alloy having a low tin content, it is inferior in mechanical strength as compared with the base material. Therefore, handling properties can be ensured by stacking a surface layer thinner than the base material on the base material.

Here, the case where a thin film of a Pb—Sn alloy containing a Sn content lower than the Sn contained in the base material is used as the surface layer 11 has been described. However, a high purity lead thin film may be used as the surface layer 11.

Next, a method for manufacturing the surface layer will be described. The surface layer is formed by rolling a rapidly solidified powder of Pb—Sn alloy or high-purity lead. Rapidly solidified powder is dropped by spraying a molten Pb-Sn alloy or high-purity lead in an inert gas atmosphere such as nitrogen or in dry air, or on a disk that rotates at high speed. Can be obtained.

When the degree of oxidation of the rapidly solidified powder exceeds 2000 ppm, j3—Pb 0 ₂ begins to be produced, which degrades the deep discharge cycle life. Therefore, it is desirable that the degree of oxidation of the rapidly solidified powder be at least 2000 ppm. If the degree of oxidation of the rapidly solidified powder is high, the amount of corrosion of the positive electrode grid increases, which is not preferable. — Less than 500 ppm is preferred to extend the deep discharge cycle life by suppressing the formation of P b 0 ₂ and further to extend the battery life in the charged state by suppressing lattice corrosion. Based on the above, the degree of oxidation of the rapidly solidified powder depends on the concentration of oxygen and moisture mixed in the manufacturing process, but is preferably less than 2000 ppm, and preferably less than 500 ppm.

Fig. 3 (A) and Fig. 3 (B) show a cross section 14 of rapidly solidified powder of high purity lead according to the present invention. FIG. 3 (C) and FIG. 3 (D) show a cross section 15 of the rapidly solidified powder of Pb—Sn alloy according to the present invention. The average particle size of the rapidly solidified powder is desirably 2 micrometers or more and 50 micrometers or less. As shown in Fig. 3 (B), crystal grains 16 exist in the rapidly solidified powder of high-purity lead, and in the rapidly solidified powder of Pb_Sn alloy, as shown in Fig. 3 (D). Confirms the presence of crystal grains 17. The size of the crystal grains is in the range of 1/1 to 1/10 that of the rapidly solidified powder.

4 and 5 show examples of rolling apparatuses for producing rolled sheets. In the example shown in FIG. 4, the rapidly solidified powder 19 put into the hopper 18 is rolled by a powder rolling roll 20 to obtain a powder rolled sheet 21 that is a raw material of the surface layer. The powder rolling sheet 21 is superimposed on a base material rolling sheet 22 that is a raw material of the base material and inserted into a rolling roll 23. From the rolling nozzle 23, a two-layered rolled sheet 24 composed of a base material 10 and a surface layer 11 is formed.

In the example shown in FIG. 5, first, the rapidly solidified powder 19 is put into a mold and press-molded to produce a molded plate 26. This molded plate 26 is rolled by a first-stage rolling roll 25 to obtain a powder rolled sheet 21 which is a raw material for the surface layer. The powder rolling sheet 21 is superposed on a base material rolling sheet 22 which is a raw material of the base material and is inserted into a rolling roll 23. From the rolling port 23, a two-layered rolled sheet 24 composed of a base material 10 and a surface layer 11 is formed.

The base material rolled sheet 22 mainly containing a Pb—C a —Sn alloy may be a known one, and may be a forged rolled sheet in the prior art. The rolling roll 23 and the first stage rolling nozzle 25 may be a multistage roll having a plurality of rolling rolls.

FIG. 6 shows a cross-sectional view of a rolled sheet that is a material of the positive electrode grid of the present invention. As shown in the figure, the surface layer 11 of the rolled sheet is perpendicular to the surface of the rolled sheet and is cut by a plane parallel to the rolling direction 27 and perpendicular to the surface of the rolled sheet. It has three cross sections, a cross section 29 cut by a plane perpendicular to the rolling direction and a cross section 30 cut by a plane parallel to the surface of the rolled sheet.

Fig. 7 (A), Fig. 7 (D), and Fig. 7 (G) are structural photographs of forged rolled sheets of Pb-Sn alloy according to the prior art. Fig. 7 (B), Fig. 7 (E), Fig. 7 (H) are structural photographs of the surface layer 11 of a powder rolled sheet of rapidly solidified powder of high purity lead according to the present invention, Fig. 7 ( C), FIG. 7 (F), and FIG. 7 (I) are photographs of the structure of the surface layer 11 of the powder-rolled sheet of Pb—Sn alloy rapidly solidified powder according to the present invention.

Fig. 7 (A), Fig. 7 (B), Fig. 7 (C) are structural photographs of the cross section 29 of the surface layer 11 cut by a plane perpendicular to the surface of the rolled sheet and perpendicular to the rolling direction, Fig. 7 (D), Fig. 7 (E), Fig. 7 (F) are structural photographs of the cross section 30 of the surface layer 11 cut by a plane parallel to the surface of the rolled sheet, Fig. 7 (G), Fig. 7 ( H) and FIG. 7 (I) are structural photographs of the cross section 28 of the surface layer 11 cut by a plane perpendicular to the surface of the rolled sheet and parallel to the rolling direction 26. The vertical direction of these structural photographs corresponds to the direction of the double arrow shown in each cross section of FIG.

Fig. 7 (A), Fig. 7 (D), Fig. 7 (G), a structural photograph of a Pb-Sn alloy forged rolled sheet according to the prior art, and Fig. 7 (B), Fig. 7 (E), As can be seen by comparing the structure photographs of the surface layer 11 according to the present invention shown in FIG. 7 (H), FIG. 7 (C), FIG. 7 (F), and FIG. 7 (I), both have different crystal grain states. . That is, in the prior art shown in FIGS. 7 (A), 7 (D), and 7 (G), the forged rolled sheet is recrystallized, so that the crystal shape is large crystal grains that are isotropically grown. It is an aggregate of and is a lump. The average grain size is over 100 micrometers. On the other hand, in the surface layer 11 according to the present invention shown in FIGS. 7B, 7E, 7H, 7C, 7F, and 7I, the surface It has a structure consisting of aggregates of crystal grains oriented in a specific direction with a cut ratio of 3 to 13. Furthermore, the average grain size of the crystal grains is smaller than 100 micrometers, and the crystal shape is flat.

In the case of the surface layer 11 of the rapidly solidified powder powder rolled sheet, the composition on the surface of the crystal grains, the composition of the dispersion (hydroxyl group, carbonyl group, SnOx, P b Ox, P b COx, adsorbed water, etc.), dispersion The grain size, dispersion state, distortion, and transition of the steel are different from the crystal grains of the forged rolled sheet. In the surface layer 11 according to the present invention, the surfaces of the rapidly solidified powder particles are bonded to form an interface between the particles. This interface is completely different from the grain boundaries of the forged rolled sheet, suppressing the progress of recrystallization seen in the forged rolled sheet and preventing the grain from becoming coarse. In addition, this interface acts to create a resistance to deformation caused by rolling and to maintain the crystal shape stretched in the rolling direction. With reference to FIG. 8, the measurement results of the tensile test of the surface layer 11 of the rolled sheet according to the present invention will be described. Fig. 8 (A) shows the shape of the test piece used in the tensile test. The longitudinal dimension of the specimen is 52 mm, the length of the neck is 30 mm, the width is 10 mm, and the thickness is 0.2 mm. Two test specimens were prepared from the powder rolled sheet according to the present invention, and two comparative test specimens were prepared from a conventional forged rolled sheet.

That is, the first test piece was produced by compacting a rapidly solidified powder of Pb—Sn alloy with a mold and rolling it. The second test piece was prepared by compacting rapidly solidified powder of high-purity lead with a mold and rolling it. The test piece of the first comparative example was produced from a conventional Pb—Sn forged rolled sheet. The test piece of the second comparative example was made from a conventional high purity lead forged sheet.

Figure 8 (B) shows the results of the tensile test. Shimadzu Autograph AGS I H500N was used as the measuring device. The gauge distance is 27mm and the strain rate is 5mmZ. As shown in the figure, in the two test pieces made from the rolled sheet according to the present invention, the tensile strength is clearly increased and the elongation rate is reduced compared with the two comparative examples made from the forged rolled sheet according to the prior art. is doing. The tensile strength of the powder-rolled sheet of the present invention is 25 ± ² NZmm ² or more and 46 ± ² NZmm ² or less, taking into account variations in measurement points. Since the powder rolling sheet is an aggregate of fine crystal grains, grain boundaries increase. Therefore, the tensile strength is increased by the grain boundary strength as compared with the forged rolled sheet of the prior art. In addition, since the powder-rolled sheets are connected by a human interface formed by bonding the surfaces of the rapidly solidified powder particles, deformation is not easily transmitted even when subjected to a tensile force, and elongation is suppressed. it can.

FIG. 9 is a structural photograph of the surface layer 11 after peeling off the positive electrode active material 4 in order to confirm the adhesion between the surface layer 11 of the rolled sheet according to the present invention and the positive electrode active material 4. FIG. 9 (A) is a photograph of a Pb—C a—S n alloy of a base material as a comparative example. That is, in order to confirm the adhesion between the Pb—Ca—Sn alloy and the positive electrode active material, the surface of the base material after the positive electrode active material was peeled was observed. Fig. 9 (B) shows a photograph of the surface layer 11 of a rapidly rolled solid powder of a Pb-Sn alloy according to the present invention, and Fig. 9 (C) shows Pb-S with Bi added according to the present invention. Fig. 9 (D) is a photograph of surface layer 11 of n-alloy rapidly solidified powder powder rolled sheet. Fig. 9 (D) shows the powder rolling of rapidly solidified powder of Pb-Sn alloy with Sr added according to the present invention. It is the photograph of the surface layer 11 by a sheet | seat. The positive electrode active material 4 may be a known one, and is obtained by applying a positive electrode active material paste obtained by kneading lead powder and red lead with a sulfuric acid aqueous solution to the upper surface of the rolled sheet and then drying it.

As shown in Fig. 9 (A), in the case of the Pb—C a—Sn alloy of the base material, the remaining of the brown cathode active material is hardly observed, and the cathode active material is completely peeled off. Therefore, the Pb—C a —Sn alloy as the base material has low adhesion to the positive electrode active material.

On the other hand, in the case of the surface layer 11 of the powder rolled sheet according to the present invention shown in FIGS. 9B, 9C, and 9D, the brown cathode active material remains. That is, the surface layer 11 of the powder rolled sheet according to the present invention has high adhesion to the positive electrode active material. In particular, the addition of Bi or Sr has the potential to further improve the adhesion.

FIG. 10 shows the measurement results of the corrosion test of the surface layer 11 of the rolled sheet according to the present invention under high temperature and overcharge conditions. Fig. 10 (A) is the measurement result of the P b -C a-S n alloy sheet of the base material as a comparative example, and Fig. 10 (B) is the rapidly solidified powder of the P b _ S n alloy according to the present invention. Fig. 10 (C) shows the measurement result of the surface layer 11 of the Pb—Sn alloy rapidly solidified powder powder rolled sheet added with Ag according to the present invention. is there. The surface layer 11 is a pre-integrated powder rolled sheet having a thickness of 0.5 mm so that the surface layer 11 and the Pb—C a —Sn alloy as the base material have the same thickness.

The conditions for the corrosion test are an aqueous sulfuric acid solution with a temperature of 75 ° C and an electrolyte density of 1.28. Each sheet was charged for 6 hours at a current density of 1 OmA / cm ² and then rested for 6 hours for 14 cycles. A known lead electrode was used as the counter electrode. The amount of corrosion was expressed as the erosion depth measured along the thickness direction.

As shown in the figure, the base Pb—Ca—Sn alloy has a large amount of corrosion and is inferior in corrosion resistance. On the other hand, it can be seen that the surface layer 11 according to the present invention has a low corrosion amount and high corrosion resistance. Furthermore, it can be seen that the addition of Ag to the Pb—Sn alloy reduces the amount of corrosion and improves the corrosion resistance.

Figure 11 shows the results of the deep discharge cycle experiment. After the deep discharge cycle test, the corrosion layer (oxide layer) of the surface layer 11 is measured by an X-ray diffractometer, and a_P b 0 ₂ (1 1 1) The inter-surface spacing d value was obtained. RINT2500 manufactured by Rigaku was used as the X-ray diffractometer. The measurement conditions were Cu ka for the X-ray source, 50kV-250mA for the X-ray output, centralized method with monochromator for the optical system, scanning speed 0.5deg / min, and sampling interval O.Oldeg / step.

The battery used in the deep discharge cycle test has the configuration shown in Fig. 1. In the deep discharge cycle, the battery was charged at 0.2C, then rested for 1 hour, and repeatedly discharged at 0.2C to 1.75V. The number of cycles when the discharge capacity dropped to 80% of the discharge capacity at the first cycle was judged as the deep discharge cycle life. The electrodes that reached the deep discharge cycle life were disassembled in a charged state, washed with water and dried, and only the corroded layer was scraped off and measured with an X-ray diffractometer.

Three positive grids were prepared using the rolled sheet according to the present invention, and two comparative positive grids according to the prior art were prepared. The first positive electrode grid of the present invention has a surface layer of a powder rolled sheet of rapidly solidified powder of high-purity lead, and the second positive electrode grid of the present invention contains 0.05 wt% Ag. It has a surface layer 11 of a rapidly solidified powder of a Pb_Sn alloy and is a surface of a powdered rolled sheet of a rapidly solidified powder of a Pb-Sn alloy. Each of the base materials is made of a Pb_C a—S n alloy sheet.

The positive electrode grid body of the first comparative example has a surface layer 11 of a rapidly rolled solid powder of a Pb—Sn alloy containing a high concentration of Sn, and a second comparative example. This positive electrode grid is composed only of a Pb—Ca—Sn alloy as a base material that does not include a surface layer. These powder-rolled sheets were produced by the manufacturing process shown in Fig. 4.

As shown in FIG. 11 (A), the crystal structure of the corrosion layer (oxide layer) formed on the surface layer 11 of the positive electrode lattice according to the present invention includes a_P b 0 ₂ , and ct_P b O ₂ ( 1 1 1) Surface spacing d value is 0.3140 ± 0.0001 nanometers or less. When the rolled sheet according to the present invention is used for the positive electrode grid, the deep discharge cycle life is improved. On the other hand, the positive electrode grid of the comparative example had a short deep discharge cycle life.

Fig. 11 (B) is a graph showing the relationship between the (1 1 1) plane spacing d value of a_P b O _{2 in} Fig. 11 (A) and the deep discharge cycle life. Therefore, to extend the life of the deep discharge cycle, the d-value between the (1 1 1) planes of a—Pb 0 ₂ is 0.3140. It is preferably ± 0.0001 nm or less and 0.3120 ± 0.0001 nm or more.

The following can be seen from the results of the adhesion evaluation test in FIG. 9, the corrosion resistance evaluation test in FIG. 10, and the deep discharge cycle life evaluation test in FIG. First, when only the Pb—Ca—Sn alloy of the base material is used as the positive electrode lattice, the adhesion to the positive electrode active material is low, the corrosion resistance is low, and the deep discharge cycle life is short. On the other hand, like the positive electrode grid of the present invention, the surface layer 11 is rolled on the base material by a powder rolling sheet of a rapidly solidified powder of Pb—Sn alloy containing Sn having a lower content than the base material. The two-layer structure has high adhesion and corrosion resistance. Further, in the case of a positive electrode grid having a surface layer 11 of a powder rolling sheet of a rapidly solidified powder of a Pb—Sn alloy containing Sn higher than the base material, the deep discharge cycle life is short. On the other hand, in the case of a positive electrode body having a surface layer 11 of a powder rolling sheet of a rapidly solidified powder of a Pb-Sn alloy containing Sn lower than the base material as in the present invention, a deep discharge cycle Long life. A deep discharge cycle life is also long in the case of a positive electrode grid having a surface layer 11 of a powder-rolled sheet of rapidly solidified powder of high-purity lead.

Next, the case where Bi, Ag, and Sr are added to the surface layer according to the present invention will be described. The characteristics of the surface layer are improved by adding Bi, Ag, and Sr to the rapidly solidified powder of the Pb_Sn alloy containing Sn lower than the base material.

First, Bi will be described. From the result of the evaluation of the adhesion to the positive electrode active material shown in FIG. 9 (C), when Bi is contained in the surface layer of the positive electrode grid, the adhesion between the surface layer of the positive electrode grid and the positive electrode active material is reduced. improves. Therefore, Bi has the function of extending the deep discharge cycle life even in expanded and punched lattices. Furthermore, Bi has the function of further promoting the production of α-Pb 0 ₂ which is essential for extending the deep discharge cycle life. In the example of Fig. 9 (C), the Bi content of the surface layer of the positive electrode grid is 5 wt%. However, from the results of Example 3 in FIG. 17 and Example 4 in FIG. 18 described below, the Bi content is preferably

It is 1% or more and 15 t% or less, More preferably, it is 0.5 wt% or more and 15 wt% or less.

Next, Ag will be described. From the evaluation results of the corrosion resistance shown in Fig. 10 (C), the corrosion resistance improves when Ag is included in the surface layer of the positive electrode lattice. Ag is under high temperature conditions, Suppresses grid corrosion in overcharge conditions, extending battery life. Furthermore, from the evaluation results of the deep discharge cycle life shown in FIG. 11 (A), when the surface layer of the positive electrode grid body contains Ag, the deep discharge cycle life is prolonged. Ag has the function of suppressing the formation of lead sulfate, which is a causative substance that decreases the deep discharge cycle life. The content of Ag is 0.5 wt% in the example shown in FIG. 10 (C), and 0.005 wt% in the example shown in FIG. 11 (A). However, from the results of Example 3 in FIG. 17 and Example 4 in FIG. 18, the Ag content is preferably 0.005 wt% or more and 0.5 wt% or less, and more preferably 0.005 wt%. % Or more and O.Olw t% or less.

Next, S r will be described. From the evaluation results of the adhesion to the positive electrode active material shown in Fig. 9 (D), the adhesion between the surface layer of the positive electrode grid and the positive electrode active material is improved when the surface layer of the positive electrode grid includes Sr. To do. When Sr is added to the surface layer 11 of the positive electrode grid body, fine precipitates are reacted to improve the adhesion with the positive electrode active material. For this reason, expanded and punched grids also have the effect of extending the deep discharge cycle life. In the example shown in Fig. 9 (D), the Sr content is l.Ow t%. However, from the results of Example 3 in FIG. 17 and Example 4 in FIG. 18, the Sr content is preferably O.Olw t% or more and l.Ow t% or less.

A second embodiment of the present invention will be described in detail with reference to FIG. Here, as an example of the present invention, an automotive lead-acid battery and a positive electrode grid body incorporated therein will be described. In the drawings to be referred to, FIG. 12 is a perspective view for explaining the configuration of an automotive lead-acid battery in which the positive electrode grid according to the present embodiment is incorporated, and is cut out in a battery case and a part of an electrode group. FIG. -¾ As shown in Fig. 12, the lead acid battery for automobile includes a positive electrode plate 36 (electrode body for lead acid battery) and a negative electrode plate 37 (electrode body for lead acid battery). The positive electrode plate 36 and the negative electrode plate 37 are arranged via a separator 38 made of a resin such as polyethylene, and a plurality of pairs of the positive electrode plate 36, the negative electrode plate 37, and the separator 38 are stacked. Thus, a laminated electrode group 39 is formed. Although not shown, in the battery case 40, six laminated electrode plate groups 39 are accommodated together with the electrolytic solution containing sulfuric acid (H ₂ S0 ₄ ). The battery case 40 is provided with a lid 42.

The positive electrode plates 36 in the laminated electrode plate group 39 are connected to each other by positive electrode ears 41 connected to the positive electrode terminal 43. Are electrically connected in parallel. Further, the negative electrode plates 37 are electrically connected in parallel by a negative electrode ear connected to the negative electrode terminal 44. The laminated electrode plate groups 39 are electrically connected in series.

The positive electrode plate 36 is provided with the positive electrode lattice body of the present invention. The shape of the positive electrode lattice is not particularly limited, and may be a punched lattice, an expanded lattice, other shapes, or a sheet shape. According to the automotive lead storage battery of the present example as described above, the same operational effects as the single plate lead storage battery according to the first embodiment can be achieved.

Compared with the conventional lead acid battery (for example, refer to patent documents 1-8), the lead acid battery for vehicles of this embodiment has confirmed the following effects. The lead acid battery for automobiles of this embodiment can extend the deep discharge cycle life. In addition, recovery chargeability does not deteriorate even when left at high temperatures and in an overdischarged state. Even in a charged state, the battery life can be extended by suppressing lattice corrosion, and the risk of short-circuiting can be reduced by suppressing corrosion growth. Even in expanded and punched lattices, adhesion to the active material is improved and the deep discharge cycle life is extended. In addition, the risk of short-circuiting can be reduced by suppressing corrosion elongation.

Even if the amount of expensive tin or silver added is small, sufficient battery characteristics can be obtained, contributing to cost reduction. In terms of manufacturing, even if a pure lead rolled sheet is used, it is easy to handle and can easily be integrated with the surface of lead-calcium alloy by rolling. In addition, there is no cracking due to corrosion, excellent corrosion resistance, and long life. Furthermore, a perforated plate of a sheet in which a conventional lead-calcium alloy is used as a base material and a lead-silver alloy layer is formed on one side of the base material and a lead-tin alloy layer is formed on the other side of the base material is a lattice. (For example, refer to Patent Document 1) A plate piece integrated using a method and a lead-calcium alloy plate and a lead-tin alloy plate is used as an electrode substrate (for example, Patent Documents 2, 3, and 4). Compared with the method, it is possible to suppress the decrease of the electrolyte caused by Sn or Ag, and to extend the deep discharge cycle life.

A third embodiment of the present invention will be described with reference to FIG. Here, as an example of the present invention, a wound lead-acid battery and a positive electrode grid body incorporated therein will be described. In the drawings to be referred to, FIG. 13 is a perspective view for explaining the configuration of a wound lead-acid battery in which the positive electrode grid body according to the present embodiment is incorporated. It is a figure which contains a notch in a part of pole group. In the present embodiment, the same components as those in the second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. As shown in FIG. 13, the wound lead-acid battery includes a positive electrode plate 36 (lead-acid battery electrode body) and a negative electrode plate 37 (lead-acid battery electrode body). In a wound lead-acid battery, a retainer 45 made of glass fiber, a negative electrode plate 37, a retainer 45, and a positive electrode plate 36 are overlapped in this order and wound around a predetermined central axis to thereby form a circle. A columnar wound electrode group 46 is formed. Although not shown, in the battery case 40, six wound electrode plate groups 46 are accommodated together with the electrolyte containing sulfuric acid (H ₂ S04). A lid 42 is attached to the battery case 40.

The positive electrode plates 36 in the laminated electrode plate group 39 are electrically connected in parallel by the positive electrode ear 41 connected to the positive electrode terminal 43. Further, the negative electrode plates 37 are electrically connected in parallel by a negative electrode ear connected to the negative electrode terminal 44. Further, the wound electrode plate groups 46 are electrically connected in series.

The positive electrode plate 36 is provided with the positive electrode lattice body of the present invention. The shape of the positive electrode lattice is not particularly limited, and may be a punched lattice, an expanded lattice, other shapes, or a sheet shape. According to the wound lead-acid battery of this example as described above, the same operational effects as the single-plate lead-acid battery according to the first embodiment can be achieved.

The wound lead-acid battery of this embodiment has confirmed the following effects as compared with conventional lead-acid batteries (for example, see Patent Documents 1 to 8). The wound lead-acid battery of this embodiment can extend the deep discharge cycle life, and the recovery chargeability does not deteriorate even when left in an overdischarged state at a high temperature. Even in the charged state, the battery life can be extended by suppressing lattice corrosion, and the risk of short-circuiting can be reduced by suppressing corrosion growth. Even in expanded and punched grids, adhesion to the active material is improved, deep discharge cycle life is increased, and corrosion growth can be suppressed to reduce the risk of short circuits. Even if the amount of expensive tin or silver added is small, sufficient battery characteristics can be obtained, contributing to lower costs. In terms of manufacturing, even if a pure lead rolled sheet is used, it has excellent handling properties and can be easily integrated into the surface of lead-calcium alloy by rolling. In addition, there is no cracking due to corrosion, excellent corrosion resistance, and long life. Furthermore, a perforated plate of a sheet in which a conventional lead-calcium alloy is used as a base material, and a lead-silver alloy layer is formed on one side of the base material and a lead-tin alloy layer is formed on the other side of the base material is a lattice. (For example, refer to Patent Document 1) The method and a plate piece integrated using a lead-calcium alloy plate and a lead-tin alloy plate are used as an electrode base (for example, refer to Patent Documents 2, 3, and 4). ) Compared to the method, it is possible to suppress the decrease of the electrolyte caused by Sn and Ag, and to extend the deep discharge cycle life.

A fourth embodiment of the present invention will be described with reference to FIG. Here, as an example of the present invention, a control valve type lead-acid battery and a positive electrode grid body incorporated therein will be described.

In the drawings to be referred to, FIG. 14 is a perspective view for explaining a configuration of a control valve type lead storage battery in which a positive electrode grid body according to the present embodiment is incorporated, and is cut out in a part of a battery case and an electrode group. FIG. In the present embodiment, the same components as those in the second and third embodiments are denoted by the same reference numerals, and detailed description thereof is omitted. As shown in FIG. 14, the control valve type lead-acid battery includes a positive electrode plate 36 (lead-acid battery electrode body) and a negative electrode plate 37 (lead-acid battery electrode body). In a control valve type lead-acid battery, a positive electrode plate 36 and a negative electrode plate 37 are arranged via a retainer 45 made of glass fiber, and a set consisting of a positive electrode plate 36, a negative electrode plate 37 and a retainer 45 is A laminated electrode plate group 47 is formed by laminating a plurality of layers. Although not shown, a laminated electrode plate group 39 is accommodated in the battery case 40 together with an electrolytic solution containing sulfuric acid (H ₂ S 0 ₄ ). The battery case 40 is provided with a lid 42.

The positive electrode plates 36 in the laminated electrode plate group 39 are electrically connected in parallel by the positive electrode ear 41 connected to the positive electrode terminal 43. Further, the negative electrode plates 37 are electrically connected in parallel by a negative electrode ear connected to the negative electrode terminal 44. The laminated electrode plate groups 39 are electrically connected in series. In the control valve type lead-acid battery, a control valve 46 for adjusting the pressure in the battery case 40 is attached.

The positive electrode plate 36 is provided with the positive electrode grid 5 of the present invention. The shape of the positive electrode lattice body 5 of the present invention is not particularly limited, and may be a punched lattice, an expanded lattice, other shapes, or a sheet shape. According to the wound lead-acid battery of this example as described above, the same effects as the single plate lead-acid battery according to the first embodiment can be obtained.

The control valve type lead acid battery of this embodiment confirmed the following effects compared with the conventional lead acid battery (for example, refer patent documents 1-8). The control valve type lead acid battery of this embodiment is Discharge cycle life can be extended, and recovery chargeability does not deteriorate even when left in an overdischarged state at high temperatures. Even in the charged state, the battery life can be extended by suppressing lattice corrosion, and the risk of short-circuiting can be reduced by suppressing corrosion growth. Even in expanded and punched grids, adhesion to the active material is improved, resulting in a longer deep discharge cycle life, reducing corrosion growth and reducing the risk of short circuits.

Even if the amount of expensive tin or silver added is small, sufficient battery characteristics can be obtained, which can contribute to cost reduction. In terms of manufacturing, even if a pure lead rolled sheet is used, it is easy to handle and can be easily integrated with the lead-calcium alloy surface by rolling. In addition, there is no cracking due to corrosion, excellent corrosion resistance, and long life.

Furthermore, a perforated plate of a sheet in which a conventional lead-calcium alloy is used as a base material, and a lead-silver alloy layer is formed on one side of the base material and a lead-tin alloy layer is formed on the other side of the base material is used for the lattice. (For example, refer to Patent Document 1) Method or plate integrated using a lead-calcium alloy plate and a lead-tin alloy plate as an electrode substrate (for example, refer to Patent Documents 2, 3, and 4) Compared to the above, it is possible to suppress the decrease of the electrolyte caused by Sn and Ag, and to extend the life of the deep discharge cycle, eliminating the need for water injection and realizing maintenance-free operation. .

According to the present invention, it is possible to provide a lead storage battery that can extend the deep discharge cycle life as compared with a conventional lead storage battery, and does not deteriorate the recovery chargeability even when left in an overdischarged state at a high temperature. Can do. Even in the charged state, the battery life can be extended by suppressing lattice corrosion, and the risk of short-circuiting can be reduced by suppressing corrosion growth. In expanded and punched grids, adhesion to the active material is improved and the life of the deep discharge cycle is extended, and the risk of short-circuiting can be reduced by suppressing corrosion growth. Further, sufficient battery characteristics can be obtained even if the amount of expensive tin or silver added is small. In terms of manufacturing, even with pure lead rolled sheets, it has excellent handling properties, can be easily integrated with the lead-calcium alloy surface by rolling, has no cracking due to corrosion, and has excellent corrosion resistance. A lead-acid battery having a long life can be provided. Next, examples of the present invention will be described.

[Example 1] Of the positive electrode grid>

As shown in FIG. 15 (A), rolled sheets F to L according to Example 1 of the present invention, rolled sheet M of Comparative Example 1 and rolled sheets 0 to Q of Comparative Example 2 were produced. FIG. 15 (A) shows the configuration of the base material 10 and the surface layer 11 of the rolled sheet.

A method for producing rolled sheets F to L according to Example 1 of the present invention will be described. Sn content force A forged slab of Pb-Ca-Sn alloy having a strength of U.2 wt% or more and 2.5 wt% or less was formed. The Pb_Ca-Sn alloy is a ternary alloy of Pb, Sn and Ca, and the content of Ca is 0.02 to 0.11 wt%. The forged slab was sequentially rolled with a multi-stage roll to produce a substrate 10.

Next, a forged slab of Pb—Sn alloy having a Sn content of 0.01 wt% or more and 0.95 wt% or less was formed. The Sn content of this forged slab is less than the Sn content of the substrate 10. A small amount of Ag, Al, Ba, Bi, Sr, etc. may be included to improve performance. This forged slab was sequentially rolled with multi-stage rolls to produce a surface layer 11 having a thickness of 0.2 mm.

Rolled sheets F to L in which the base material 10 and the surface layer 11 were integrated were prepared by simultaneously superimposing the surface layer 11 on the base material 10 and rolling. The rolled sheets F to L were expanded to form a mesh portion, and a positive electrode grid 5 shown in FIG. 1 was obtained. The base material 10 and the surface layer 11 can also be subjected to an aging treatment.

A method for producing the rolled sheet M of Comparative Example 1 will be described. A forged slab of Pb_C-a-Sn based alloy having a Sn content of 1.4 wt% and a Ca content of 0.09 wt% was formed. P b—C a -S n alloy is a ternary alloy of P b, Sn and Ca. The forged slab was sequentially rolled with a multi-stage roll to produce a substrate 10 having a thickness of 1.2 mm. This substrate 10 is Comparative Example 1. The rolled sheet M of Comparative Example 1 is composed of the base material 10 and does not include the surface layer 11. This rolled sheet M was expanded to form a mesh portion, and a positive electrode grid 5 shown in FIG. 1 was obtained.

A method for producing the rolled sheets 0 to Q of Comparative Example 2 will be described. A forged slab of Pb-Ca-Sn alloy having a Sn content of 1.4 wt% and a Ca content of 0.09 wt% was formed. Pb-Ca-Sn alloy is a ternary alloy of Pb, Sn, and Ca. The forged slab was sequentially rolled with a multi-stage roll to produce a substrate 10. Next, a forged slab of Pb—Sn alloy having an Sn content of 1.4 wt% or more and 4 wt% or less was formed. The content of Sn in this forged slab is higher than the content of Sn in the base material 10. The forged slab was sequentially rolled with a multi-stage roll to produce a surface layer 11 having a thickness of 0.2 mm.

Rolled sheets 0 to Q in which the base material 10 and the surface layer 11 were integrated were produced by simultaneously superimposing the surface layer 11 on the base material 10 and rolling. The rolled sheets 0 to Q were expanded to form a mesh portion, and a positive electrode grid 5 shown in FIG. 1 was obtained. The base material 10 and the surface layer 11 can also be subjected to an aging treatment.

Of the positive electrode plate>

Polyester fiber was added to the mixture of lead powder and red lead, and water and dilute sulfuric acid (specific gravity 1.26, 20 ° C) were added to it. This was kneaded to produce a positive electrode active material paste. This positive electrode active material paste 58 g was obtained from the positive electrode grid 5 obtained from the above-described rolled sheets F to L according to Example 1 of the present invention and the rolled sheets M and 0 to Q of Comparative Examples 1 and 2. The lattice 5 was filled. The size of the collector grid of the positive grid 5 was 1 16 mm X I 00 mm X 1.2 mm. These positive electrode grids 5 were left to mature for 18 hours in an atmosphere of 50 ° C and humidity of 98RH%, and then left to dry at a temperature of 110 ° C for 2 hours. Was made.

To the lead powder, 0.3% by mass of lignin, 0.2% by mass of barium sulfate, and 0.1% by mass of carbon powder were added. Polyester fiber was added thereto and kneaded for about 10 minutes with a kneader. Then, 12% by mass of water is further added to and mixed with the obtained mixture, and further 13% by mass of diluted sulfuric acid (specific gravity 1.26, 20). ° C) was added to prepare a negative electrode active material paste. 47 g of this negative electrode active material paste was filled into a current collector grid made of a lead-calcium-muum alloy having dimensions of 1 16 mm × 10 Omm × 0.9 mm. This negative electrode plate was left to mature for 18 hours in an atmosphere of 50 ° C and humidity of 98 RH%, then left to dry for 2 hours at a temperature of 10 ° C, and the unformed negative electrode plate 2 was removed. Produced.

Manufacturing of single plate lead acid battery>

Using the produced positive electrode plate 1 and negative electrode plate 2, the single plate lead-acid battery shown in Fig. 1 was produced. . The electrolyte used was dilute sulfuric acid with a specific gravity of 225 (20 ° C). In addition, the chemical conversion of the single plate lead-acid battery was performed at 2.4A for hours. After the chemical conversion, dilute sulfuric acid having a specific gravity of 1.4 (20 ° C) was added, and the electrolyte was adjusted to become dilute sulfuric acid having a specific gravity of 1.28 (20 ° C). The obtained single plate lead-acid battery had a battery capacity of 7 Ah and an average discharge voltage of 2 V.

Using the rolled sheet M of Comparative Example 1, a single plate lead battery was produced in the same manner as Example 1 of the present invention.

Deep discharge cycle experiments were conducted on these single plate lead-acid batteries. The charging current was 1.4 A, and 30% of the discharge capacity was charged. The discharge capacity was calculated from the discharge time until the lower limit voltage reached 1.75 V at a discharge current of 1.4A.

Figure 15 (B) shows the deep discharge cycle characteristics. The vertical axis represents the discharge capacity (Ah), and the horizontal axis represents the number of cycles (times). As shown in FIG. 15 (B), the single plate lead-acid battery using the rolled sheets F to L according to the present invention showed an excellent deep discharge cycle life. The content of C a in the base material is preferably 0.05 to 0.09 wt% considering both handling properties and corrosion resistance. Further, the content of Sn in the substrate is preferably 1.2 wt% to 1.9 wt% in consideration of both cost and suppression of the amount of electrolyte decrease. Single plate lead-acid batteries using rolled sheets M, 0 to Q of Comparative Examples 1 and 2 have a short deep discharge cycle life.

Recovery Charging Characteristics Evaluation>

The battery was overdischarged at a discharge current of 1.4 A until the lower limit voltage reached 1.6 V, and left at 45 ° C for 2 weeks. The single plate lead-acid battery after charging was charged with 150% of the discharge capacity at a charging current of 1.4A. From the discharge time until the lower limit voltage reached 1.75V at a discharge current of 1.4A, the discharge capacity after overdischarge and left-over recovery charge was determined. The single plate lead-acid battery using the rolled sheets F to L according to Example 1 of the present invention had good recovery charge characteristics, and the discharge capacity was 80% or more of the battery capacity.

In the single plate lead-acid battery of the present invention, it is desirable to use an aqueous sulfuric acid solution in which 0.01 wt% or more and 5 wt% or less of magnesium sulfate or sodium sulfate is added to the electrolyte. By using such a sulfuric acid aqueous solution, the recovery charge performance during overdischarge can be improved. [Example 2]

As shown in FIG. 16 (A), rolled sheets R to V according to Example 2 of the present invention were manufactured. FIG. 16 (A) shows the ratio of the thickness of the base material 10 and the surface layer 11 of the rolled sheet. A method for producing the rolled sheets R to V according to Example 2 of the present invention will be described. A forged slab of Pb_Ca—Sn alloy with a Sn content of 1.4 wt% and a Ca content of 0.09 wt% was formed. P b—C a—S n alloy is a ternary alloy of P b, Sn and Ca. This forged slab was sequentially rolled with a multi-stage roll to produce a substrate 10.

Next, a forged slab of Pb—Sn alloy having an Sn content of 0.1 wt% was formed. The Sn content of this forged slab is less than the Sn content of the substrate 10. In order to improve performance, a small amount of A g Al, Ba, Bi, Sr, etc. may be included. The forged slab was sequentially rolled with a multi-stage roll to produce a surface layer 11.

Rolled sheets R to V were produced by superimposing the surface layer 11 on the base material 10 and rolling it simultaneously. In these rolled sheets R to V, the ratio of the surface layer thickness (Y) 13 to the base material thickness (X) 12 shown in FIG. 6, that is, ¥: is in the range of 1: 5 to 1:70. The thickness of the rolled sheet R to V is in the range of 0.7 to 3.2 mm. The rolled sheets R to V were expanded to form a mesh part, and the positive electrode grid 5 shown in FIG. 1 was obtained. The base material 10 and the surface layer 11 can each be subjected to an aging treatment. Using these rolled sheets R to V, a single plate lead-acid battery was produced in the same manner as in Example 1, and the deep discharge cycle life was measured under the same conditions.

Figure 16 (B) shows the measurement results of the deep discharge cycle life. As shown in the figure, the single plate lead-acid battery using the rolled sheets R to T of Example 2 showed a relatively excellent deep discharge cycle life. However, the single plate lead-acid battery using the rolled sheets U and V of Example 2 had a relatively short deep discharge cycle life. Therefore, when the single plate lead-acid battery using the rolled sheets U and V was disassembled, the corrosion on the surface layer of the positive electrode grid was slightly advanced. Compared with the single plate lead-acid battery using the rolled sheets M and 0 to Q of Comparative Examples 1 and 2 shown in FIG. 15 (B), the single unit using the rolled sheets R to V according to Example 2 of the present invention is used. Plate lead-acid batteries have good deep discharge cycle life. From this result, the ratio of the thickness (Y) 13 of the surface layer to the thickness (X) 12 of the substrate, that is, Y: X is in the range of 1:10 to 1:60. preferable.

[Example 3]

As shown in FIG. 17, jl-rolled sheets W to Z and a to k according to Example 3 of the present invention were manufactured. FIG. 17 shows the configuration of the base material 10 and the surface layer 11 of the rolled sheet.

The manufacturing method of the rolled sheets WZ and ak by Example 3 of this invention is demonstrated. A forged slab of Pb—C a—S n alloy with an Sn content of 1.4 wt% and a Ca content of 0.09 wt% was formed. P b _C a—S n alloy is a ternary alloy of P b, Sn and Ca. The forged slab was sequentially rolled with a multi-stage roll to produce a substrate 10.

Next, the Sn content is 0.2wt%, including Ag, Al, Ba, Bi, 3 ::? A forged slab of 13_Sn alloy was formed. The Sn content of this forged slab is less than the Sn content of the substrate 10. The forged slab was sequentially rolled with a multi-stage roll to produce a surface layer 11 having a thickness of 0.2 mm.

Rolled sheets W to Z and a to k in which the base material 10 and the surface layer 11 were integrated were produced by superimposing the surface layer 11 on the base material 10 and rolling it simultaneously. The rolled sheet was expanded to form a mesh portion, and a positive electrode grid 5 shown in FIG. 1 was obtained. The base material 10 and the surface layer 11 can each be subjected to an aging treatment. Using this, a single plate lead-acid battery was produced in the same manner as in Example 1, and a deep discharge cycle test was conducted under the same conditions.

Figure 17 shows the deep discharge cycle life of single-plate lead-acid batteries using rolled sheets W to Z and a to k. The number of cycles when the discharge capacity dropped to 60% of the discharge capacity at the first cycle was determined as the deep discharge cycle life. Single plate lead-acid batteries using rolled sheets YW ~ j containing Ag, Al, Ba, Bi, or Sr showed relatively good deep discharge cycle life. However, the single plate lead-acid battery using the rolled sheet k that does not contain Ag, Al, Ba, Bi, and Sr showed a relatively short deep discharge cycle life. However, compared with the single plate lead-acid battery using the rolled sheets M and 0 to Q of Comparative Examples 1 and 2 shown in Fig. 15 (B), the single plate lead-acid battery using the rolled sheet k has good deep discharge. Indicates cycle life. From this result, the content of A l, Ba, Sr is O.Olw t% or more l.Ow t% or less, the content of Ag is 0.005 wt% or more and less than O.Olw t%, the content of B i If the amount is 0.5wt% or more and 15wt% or less, the service life is improved. As a result of disassembling these single plate lead-acid batteries and observing the positive electrode lattice, it was found that the positive electrode lattice containing Ag and A 1 had excellent corrosion resistance. It was found that lattice elongation can be suppressed when Ba is included in the positive electrode lattice. A single plate lead-acid battery using a rolled sheet containing Bi was disassembled and the surface of the positive electrode grid was measured by X-ray diffraction. As a result, the peak strength ratio of Hi Pbo ₂ was high. This indicates that more a—P b O ₂ is produced.

The positive grid produced from a rolled sheet containing Sr or Bi had very good adhesion to the active material. Therefore, if Sr or Bi is attached, sufficient battery characteristics can be obtained even if the amount of expensive tin or silver added is small, which can contribute to cost reduction.

[Example 4]

As shown in FIG. 18 (A), rolled sheets 1 to t according to Example 4 of the present invention were manufactured. FIG. 18 (A) shows the configuration of the base material 10 and the surface layer 11 of the rolled sheets 1 to t. A method for producing rolled sheets 1 to t according to Example 4 of the present invention will be described. A forged slab of Pb—C a—S n alloy with an Sn content of 1.4 wt% and a Ca content of 0.09 wt% was formed. Pb—C a _Sn alloy is a ternary alloy of Pb, Sn and Ca. This forged slab was sequentially rolled with a multi-stage roll to produce a substrate 10.

The surface layer 11 of the rolled sheets 1 to q was produced by powder rolling a rapidly solidified powder of high-purity lead. However, Al, Ba, Sr, Ag, and Bi are added to the surface layer 11 of the rolled sheets 1 to p. The surface layer 11 of the rolled sheet q is made of high-purity lead and does not contain additives. Rolled sheet! The surface layer 11 of: to t was produced by powder rolling a rapidly solidified powder of a Pb—Sn alloy containing Sn having a lower content than Sn of the base material. Thus, a surface layer 11 having a thickness of 0.2 mm was obtained by powder rolling. Rolled sheets 1 to t in which the base material 10 and the surface layer 11 were integrated were produced by superimposing the surface layer 11 on the base material 10 and rolling it simultaneously. The rolled sheet was expanded to form a mesh part, and a positive electrode grid 5 shown in FIG. 1 was obtained.

These rolled sheets! : Surface layer 11 of t is the powder rolling sheet shown in Fig. 7 (B), Fig. 7 (E), Fig. 7 (H), Fig. 7 (C), Fig. 7 (F), Fig. 7 (I) It had a characteristic organizational section. A method for producing the rolled sheet u of Comparative Example 3 will be described. A forged slab of Pb-Ca-Sn alloy having a Sn content of 1.4 wt% and a Ca content of 0.09 wt% was formed. Pb-Ca-Sn alloy is a ternary alloy of Pb, Sn and Ca. The forged slab was sequentially rolled with a multi-stage roll to produce a substrate 10. A surface layer 11 of a 0.2 mm forged rolled sheet was prepared by rolling high purity lead forged slabs sequentially in a multi-stage neck. The surface layer 11 was superposed on the base material 10 and rolled at the same time to produce a rolling sheet u in which the base material 10 and the surface layer 11 were integrated. The rolled sheet was expanded to form a mesh portion, and a positive electrode grid 5 shown in FIG. 1 was obtained.

Next, a positive electrode plate was produced from these positive electrode grids 5 in the same manner as in Example 1. Further, in the same manner as in Example 1, a negative electrode plate was produced and a single plate lead-acid battery was produced. For these single plate lead-acid batteries, a deep discharge cycle experiment was conducted in the same manner as in Example 1. The conditions of the deep discharge cycle experiment are the same as in Example 1 according to the present invention.

Figure 18 (B) shows the deep discharge cycle characteristics. The vertical axis represents the discharge capacity (Ah), and the horizontal axis represents the number of cycles (times). The single plate lead-acid battery using the rolled sheets q to t according to Example 4 of the present invention showed excellent deep discharge cycle life. Further, although not shown in FIG. 18 (B), the single plate lead-acid battery using the rolled sheet to p according to Example 4 of the present invention showed a further excellent deep discharge cycle life. In particular, the rolled sheets 1 to t according to Example 4 have high tensile strength, excellent handling properties, and excellent workability when the substrate 10 is rolled with the surface layer 11 superimposed thereon. Furthermore, there was no delamination between the substrate 10 and the surface layer 11, and an excellent deep discharge cycle life was exhibited.

On the other hand, in the single plate lead-acid battery using the rolled sheet u of Comparative Example 3, the capacity rapidly decreased at the beginning of the cycle, and a short deep discharge cycle life was shown. When this single plate lead-acid battery was disassembled and the positive electrode plate lattice was observed, it was found that the surface layer 11 and the base material 10 were separated, and lead sulfate formation occurred at the boundary surface. In particular, the forged rolled sheet u of Comparative Example 3 has a lower tensile strength and is softer than the rolled sheets 1 to t according to Example 4 of the present invention, and is inferior in handling properties. When rolling with the 11 stacked, processing cuts occurred, making integration difficult.

The recovery charge characteristics similar to those of Example 1 were evaluated for Example 4 of the present invention. According to it, single plate lead electricity storage using rolled sheets 1 to t according to Example 4 of the present invention The battery had good recovery charge characteristics, and the discharge capacity was 80% or more of the battery capacity. On the other hand, the single plate lead-acid battery using the rolled sheet u of Comparative Example 3 had poor recovery charge characteristics, and the discharge capacity was 50% or less of the battery capacity.

From Example 1 in FIG. 15, Example 2 in FIG. 16, Example 3 in FIG. 17 and Example 4 in FIG. First, from Example 1 in FIG. 15, the Ca content of the base material is 0.02 wt% or more and O.llw t% or less, and preferably 0.02 wt% or more and 0.09 wt% or less. The content of Sn in the substrate is 1.2 wt% or more and 2.5 wt% or less, and preferably 1.2 wt% or more and 1.9 wt% or less. The content of Sn in the surface layer is O.Olw t% or more and l.Ow t% or less, which is less than the Sn content of the substrate.

From Example 2 in FIG. 16, from the ratio of surface layer thickness (Y) to substrate thickness (X), ie Y: X is in the range of 1: 5 to 1:70, preferably , 1: 1 0 ~: 1: 60 range.

Next, A 1 will be described. From Example 3 in Fig. 7, from the surface layer of Pb-Sn alloy whose Sn content is lower than the Sn content of the base material, the content of A1 is more than O.Olw%. Ow t% or less, preferably O.Olw t% or more and 0.5 wt% or less.

A 1 is known to function as an antioxidant (reducing agent) during fabrication. Therefore, the addition of A1 to the forged alloy can reduce oxides and other voids. Therefore, when A 1 is added to the rapidly solidified powder of Pb—Sn alloy containing Sn lower than the base material according to the present invention, A 1 functions as an antioxidant (reducing agent). Therefore, the natural oxidation is suppressed, and a rapidly solidified powder having a low degree of oxidation is obtained.

Oxides and oxide voids generated by natural oxidation in the rapidly solidified powder cause corrosion and should be reduced. In particular, _Pb 0 ₂ can cause a decrease in deep discharge cycle life. Therefore, preferably Rukoto reduce as much as possible i3- P b 0 _2.

When A 1 is added to the surface layer 11, corrosion can be suppressed even when the amount of expensive tin or silver added is small, and sufficient battery characteristics can be obtained. Moreover, even when the surface layer of the positive electrode grid is formed by a pure lead rolled sheet, the addition of A 1 suppresses the formation of oxides and the like due to natural oxidation. Therefore, the rolled sheet of pure lead can be easily integrated with the lead-calcium alloy surface by rolling. In this way, there is no cracking due to corrosion, It can provide lead-acid batteries with excellent food quality and long life.

Next, Ba will be described. From Example 3 in FIG. 17 and Example 4 in FIG. 18, the Ba content is preferably O.Olw t% or more and l.Ow t% or less. When Ba is added to the surface layer 11 of the positive electrode grid, the adhesion between the corroded particles is lowered, and even when the corrosion progresses, the strain accompanying the volume expansion is easily relaxed. In addition, the risk of short-circuiting can be reduced by suppressing corrosion growth.

Next, S r will be described. From Example 3 in FIG. 17 and Example 4 in FIG. 18, the Sr content is preferably O.Olw t% or more and l.Ow t% or less.

Next, Ag will be described. From Example 3 in FIG. 7 and Example 4 in FIG. 18, the Ag content is 0.005 wt% or more and O. Olw t% or less, preferably 0.005 wt% or more and 0.008 wt% or less. .

Next, B i will be described. From Example 3 in FIG. 17 and Example 4 in FIG. 18, the Bi content is preferably O.lw t% or more and 15 w t% or less.

From the above, the contents of A1, Ba and Sr in the surface layer 11 of the positive electrode grid body may be O.Olw t% or more and l.Ow t% or less.

According to the present invention, the positive electrode grid for a lead-acid battery is based on a lead-calcium alloy of the prior art (see, for example, Patent Document 1), and a lead-silver alloy layer on one side of the substrate. Compared to a perforated plate with a lead-tin alloy layer formed on each other, sufficient corrosion resistance and a long deep discharge cycle life can be obtained. In addition, sufficient recovery chargeability can be obtained even when left overdischarged at high temperatures. Furthermore, sufficient battery characteristics can be obtained even if the amount of expensive tin or silver added is small.

The positive electrode grid for a lead-acid battery according to the present invention has a higher tin content in a lead-tin alloy than in a lead-calcium-tin-tin alloy (for example, Patent Documents 2, 3, Compared to (4), sufficient corrosion resistance and a long deep discharge cycle life can be obtained. In addition, even when left overdischarged at high temperatures, sufficient recovery chargeability and sufficient life extension effect can be obtained.

The positive electrode grid for a lead storage battery of the present invention is a grid obtained by processing a rolled sheet made of pure lead containing no antimony, or a grid having a thin layer of high purity lead metal rolled and integrated on the surface. Compared to the conventional technology used, lattice corrosion is reduced and corrosion elongation is suppressed. Thus, a battery having a longer life that can reduce the risk of short circuit is obtained. Even if the grid beam width is less than 1.2 times the sheet thickness, the corrosion of the grid can be reduced compared to the conventional technology (see, for example, Patent Document 5), and the risk of short-circuiting by suppressing the corrosion elongation. And a battery with a longer life can be obtained.

The positive electrode grid for a lead storage battery according to the present invention is superior in handling property to lead-calcium in comparison with the prior art (see, for example, Patent Document 6) even when a pure lead rolled sheet is integrated on the surface. It can be easily integrated on the surface of the base alloy by rolling, has no cracks due to corrosion, and has a long life. Compared to the prior art (for example, see Patent Document 7) in which a lead-tin alloy layer is integrated on the surface of a pure lead plate, sufficient strength can be obtained as a positive electrode grid body, and the handling property is excellent. In addition, it exhibits superior corrosion resistance as compared with the conventional technique in which the average crystal grain size is coated with a Pb sheet having a micrometer of at least 100 micrometers (for example, see Patent Document 8).

The example of the present invention has been described above, but the present invention is not limited to the above-described example, and various modifications can be easily made by those skilled in the art within the scope of the invention described in the claims. Will be understood.

Claims

The scope of the claims

I. A positive electrode plate having a positive electrode lattice body and a positive electrode active material filling the positive electrode lattice body, a negative electrode plate having a negative electrode lattice body and a negative electrode active material filling the negative electrode lattice body, the positive electrode plate, and the negative electrode In the lead storage battery having a separator provided between the plates, the positive electrode lattice body includes a base material mainly containing a Pb—C a—S n alloy and S having a lower content than Sn contained in the base material. A lead-acid battery comprising a surface layer containing a Pb—Sn alloy containing n.

2. The lead-acid battery according to claim 1, wherein the surface layer is composed of a rolled layer of rapidly solidified powder of a Pb—Sn alloy.

3. The lead storage battery according to claim 1, wherein the thickness ratio between the surface layer and the substrate is in the range of 1:10 to 1:60.

4. The lead acid battery according to claim 1, wherein the Sn content in the surface layer is not less than 0.1 wt% and less than l wt%.

5. A positive electrode plate having a positive electrode lattice body and a positive electrode active material filled in the positive electrode lattice body, a negative electrode lattice body, a negative electrode plate having a negative electrode active material filled in the negative electrode lattice body, the positive electrode plate, and the above In the lead storage battery having a separator provided between the negative electrode plates, the positive electrode grid is composed of a base material mainly containing a Pb—C a _Sn alloy and a rolled layer of rapidly solidified powder of high-purity lead. Lead acid battery characterized by having a surface layer.

6. The lead-acid battery according to claim 2 or 5, wherein the rapidly solidified powder has an oxidation degree of less than 2000 ppm, preferably less than 500 ppm.

7. The lead acid battery according to claim 2 or 5, wherein the rapidly solidified powder has an average particle diameter of 2 micrometers or more and 50 micrometers or less.

8. The lead-acid battery according to claim 1, 2 or 5, wherein the surface layer has crystal particles oriented in a specific direction having an aspect ratio of 3 to 13.

9. The lead acid battery according to any one of claims 1 to 8, wherein the surface layer contains at least one of Bi, Ag, Ba, Sr, and A1. .

10. The lead-acid battery according to claim 9, wherein the content of A 1, Ba, Sr in the surface layer is O.Ol w t% or more and l.Ow t% or less.

II. The Ag content in the surface layer is 0.005 wt% or more and less than O.Olw t%. The lead acid battery according to claim 9, wherein:

10. The lead-acid battery according to claim 9, wherein the Bi content in the surface layer is 0.5 wt% or more and 15 wt% or less.

1 3. The surface layer has a tensile strength of 25 ±

The lead-acid battery according to claim 1, 2 or 5, wherein a rolled sheet of 2NZmm ² or less is used.

14. The lead according to claim 1, 2, or 5, wherein magnesium sulfate or an aqueous sulfuric acid solution to which sodium sulfate is added is used as an electrolytic solution impregnated in the positive electrode plate, the negative electrode plate, and the separator. Storage battery.

15. The lead acid battery according to any one of claims 1 to 14, which is an automotive lead acid battery, a wound lead acid battery, or a control valve type lead acid battery.

. 1 6 wherein comprises a crystal structure alpha-P B_〇 _second oxide layer formed on the surface layer, and, ct - P b 0 ₂ (1 1 1) plane spacing d value of the surface is 0 · 3140 ± The lead-acid battery according to claim 1, 2 or 5, characterized in that it is 0.0001 nanometer or less 0.3120 ± 0.0001 nanometer or more.

1 7. A positive electrode plate for a lead storage battery having a positive electrode grid and a positive electrode active material filling the positive grid, wherein the positive electrode grid includes a base material mainly containing a Pb—Ca—Sn alloy and the substrate. A surface layer arranged so as to be stacked by rolling on the material, and the surface layer is made of a Pb—Sn alloy containing Sn having a lower content than Sn contained in the base material. A positive electrode plate for a lead-acid battery, comprising a rolled layer of rapidly solidified powder or a rolled layer of rapidly solidified powder of high-purity lead.

18. The surface layer has crystal particles oriented in a specific direction having an aspect ratio of 3 to 13, and the degree of oxidation of the rapidly solidified powder is less than 2000 ppm, preferably less than 500 ppm. The positive electrode plate for a lead storage battery according to claim 17.

1 9. Making a base rolled sheet mainly containing P b—C a—S n alloy;

A powder rolled sheet of a rapidly solidified powder of Pb—Sn alloy containing Sn having a lower content than Sn contained in the base material or a powder rolled sheet of a rapidly solidified powder of high-purity lead is prepared. And

The powder rolling sheet is stacked on the base material rolling sheet, Rolling to produce a rolled sheet;

Cutting the rolled sheet to produce a positive electrode grid;

Applying a positive electrode active material to the positive electrode grid and drying to create a positive electrode plate; combining a negative electrode plate, a separator and the positive electrode plate;

A method for producing a lead-acid battery comprising:

20. The rolled powder sheet has crystal particles oriented in a specific direction with an aspect ratio of 3 to 13, and the degree of oxidation of the rapidly solidified powder is less than 2000 ppm, preferably less than 500 ppm. The method for producing a lead-acid battery according to claim 19, wherein the lead-acid battery is produced.