JP2012142185A - Lead acid battery and idling stop vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve idling stop life performance both at high temperature and normal temperature in a lead acid battery.SOLUTION: A lead acid battery includes: a negative electrode plate; a positive electrode plate; and an electrolyte soaking the negative electrode plate and the positive electrode plate. The grid skeleton of the negative electrode plate of the lead acid battery has a lead-antimony alloy layer on at least a part of a surface of the grid skeleton, and the electrolyte contains lithium ions and aluminum ions.

Description

  The present invention relates to a lead-acid battery and an idling stop vehicle using the same, and more particularly to a lead-acid battery used for improving idling stop life performance.

  Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2009-266514) discloses that the lead-tin-antimony alloy layer is provided on the surface of the negative electrode lattice of the lead-acid battery to suppress the negative electrode from being burnt in the idling stop mode. is doing. Patent Document 1 describes that the mechanism for suppressing the ear burn is because the potential of the negative electrode is increased by tin and antimony in the alloy layer. The inventors have also independently confirmed that when a lead-antimony alloy layer is provided on the surface of the negative-electrode lattice frame, it is possible to prevent the negative electrode from being burnt in the idling stop mode.

  Patent Document 2 (Japanese Patent Laid-Open No. 2008-243489) discloses that lead electrolyte battery electrolyte contains 0.01 mol / L to 0.3 mol / L of aluminum ions and the content of sodium ions is 0.002 mol / L to 0.05 mol / L. Is disclosed. Patent Document 3 (Japanese Patent Laid-Open No. 2008-243487) discloses that an electrolytic solution of a lead storage battery contains 0.01 mol / L to 0.3 mol / L of aluminum ions and 0.14 mol / L or less of lithium ions. . Patent Documents 2 and 3 indicate that sulfation can be suppressed by these configurations.

  The idling stop life performance is determined to be measured at 25 ° C. according to the battery industry association standard (SBA S 0101: 2006). However, considering the driving of automobiles in summer and the driving of automobiles in regions with high temperatures, the idling stop life performance at temperatures higher than 25 ° C becomes a problem. At a high temperature such as 60 ° C., the life in the idling stop mode is often reached by the sulfation of the negative electrode rather than the thinning of the negative electrode. Here, sulfation is a phenomenon in which the active material of the negative electrode changes to coarse crystals of lead sulfate that are difficult to reduce. Therefore, the inventor has studied to suppress the earring of the negative electrode at room temperature and the sulfation at high temperature in order to improve the idling stop life performance, and arrived at the present invention.

JP2009-266514 JP2008-243489 JP2008-243487

  The basic problem of the present invention is to improve the idling stop life performance at both high temperature and normal temperature.

The present invention is a lead storage battery comprising a negative electrode plate, a positive electrode plate, and an electrolyte solution that immerses the negative electrode plate and the positive electrode plate,
The lattice frame of the negative electrode plate is provided with a lead-antimony alloy layer on at least a part of the surface,
The electrolyte is in a lead acid battery containing lithium ions and aluminum ions.

The present invention is also a lead storage battery comprising a negative electrode plate, a positive electrode plate, and an electrolyte solution for immersing the negative electrode plate and the positive electrode plate,
The lattice frame of the negative electrode plate is provided with a lead-antimony alloy layer on at least a part of the surface,
The electrolytic solution contains lithium ions and aluminum ions, and has a sodium ion content of 0.04 mol / L or less.

Preferably, the electrolytic solution contains 0.02 mol / L or more and 0.2 mol / L or less lithium ions and 0.02 mol / L or more and 0.2 mol / L or less aluminum ions.
Preferably, the antimony content of the lead-antimony alloy layer is 1% by mass or more and 10% by mass or less.

  Furthermore, the present invention resides in an idling stop vehicle equipped with the above lead storage battery.

  The lead-acid battery of the present invention exhibits a high life performance under PSOC (Partial State of Charge) that operates mainly in a state where the charged state is less than 100%, and particularly has a high life performance in a wide temperature range from room temperature to high temperature. Demonstrate. The use of the lead storage battery is arbitrary, but if it is a start storage battery for an idling stop vehicle, it will be a long-life storage battery at room temperature or high temperature. In this specification, 1 mol of aluminum ions corresponds to 171.05 g of aluminum sulfate.

In order to improve the life performance at room temperature in the idling stop mode, as pointed out in Patent Document 1, it is effective to provide a lead-antimony alloy layer on the surface of the negative electrode lattice. However, to improve the life performance at room temperature and high temperature,
A lead-antimony alloy layer having an antimony content of 1% by mass or more and 10% by mass or less on the surface of the negative electrode lattice;
The content of sodium ions in the electrolyte is 0.04 mol / L or less, preferably 0.02 mol / L or less;
The content of lithium ions in the electrolyte is 0.02 mol / L or more and 0.2 mol / L or less, preferably 0.1 mol / L or more and 0.2 mol / L or less;
The content of aluminum ions in the electrolyte is 0.02 mol / L or more and 0.2 mol / L or less, preferably 0.1 mol / L or more and 0.2 mol / L or less;
It was necessary to improve the life performance at room temperature and high temperature specifically (Table 1).

  Next, when the influence of the antimony content in the alloy layer was examined, it was found that antimony was 1% by mass or more and that high life performance was obtained at room temperature or high temperature (FIG. 2), and the antimony content was 10% by mass. Since it is difficult to produce an alloy layer that exceeds the content, the antimony content is set to 1% by mass or more and 10% by mass or less. When the influence of the sodium ion content in the electrolyte solution was examined, it was found that when the sodium ion content exceeded 0.04 mol / L, the life performance at high temperatures deteriorated (FIG. 3). Of 0.04 mol / L or less. Although the short circuit resistance and overdischarge performance are deteriorated by reducing the sodium ion content, it can be avoided by containing lithium ions described later. The lower limit of the sodium ion content is zero.

  When the influence of the lithium ion content in the electrolytic solution was investigated, the life performance at high temperature improved at 0.02 mol / L or more, and when it exceeded 0.2 mol / L, the high-temperature life performance and room temperature life performance began to decline ( Therefore, the lithium ion content was set to 0.02 mol / L or more and 0.2 mol / L or less. When the influence of the aluminum ion content in the electrolytic solution was examined, the life performance improved at room temperature and high temperature at 0.02 mol / L or more, and the life performance began to decline at around 0.2 mol / L at both high temperature and room temperature (Fig. 5). Therefore, the aluminum ion content was set to 0.02 mol / L or more and 0.2 mol / L or less.

Cross-sectional view of negative electrode grid in Example This is a characteristic diagram showing how the antimony content in the lead-antimony alloy layer provided on the negative electrode lattice frame affects the life performance. The sodium ion content of the electrolyte is 0.005 mol / L, the lithium ion The content is fixed at 0.1 mol / L and the aluminum ion content is fixed at 0.05 mol / L. This is a characteristic diagram showing how the sodium ion content of the electrolyte affects the life performance.The antimony content in the lead-antimony alloy layer is fixed at 5% by mass, and the lithium ion content is 0.1 mol / The aluminum ion content is fixed at 0.05 mol / L. A characteristic diagram showing how the lithium ion content of the electrolyte affects the lifetime performance.The antimony content in the lead-antimony alloy layer is fixed at 5% by mass, and the sodium ion content is 0.005 mol / The aluminum ion content is fixed at 0.05 mol / L. This is a characteristic diagram showing how the aluminum ion content of the electrolyte affects the life performance. The antimony content in the lead-antimony alloy layer is fixed at 5% by mass, and the sodium ion content is 0.005 mol / Lithium ion content is fixed at 0.1 mol / L.

  Embodiments of the present invention will be described below. The implementation of the present invention can be changed as appropriate according to the common knowledge of those skilled in the art and the disclosure of the prior art.

The lead storage battery according to the present invention includes a negative electrode plate in which a negative electrode active material is held in a negative electrode lattice frame, a positive electrode plate in which a positive electrode active material is held in a positive electrode lattice frame, and an electrolyte solution that immerses the negative electrode plate and the positive electrode plate The negative electrode lattice frame includes a lead-antimony-based alloy layer on a part (or at least a part) of the surface, and the electrolytic solution contains lithium ions and aluminum ions. It is characterized by that.
The lead-antimony alloy layer has an antimony content of 1% by mass or more and 10% by mass or less, and the electrolyte contains 0.02 mol / L or more and 0.2 mol / L or less of lithium ions and 0.02 mol / L or more and 0.2 mol / L or less. The following aluminum ions are contained, and the content of sodium ions is 0.04 mol / L or less.
As the positive grid and the negative grid, an expanded grid is widely used, but a punched grid or a cast grid may be used.

  The lead-antimony-based alloy layer on the surface of the negative electrode lattice part need not be provided on the entire surface. As described in the examples below, the lead-antimony alloy layer is provided only on one side of the rolled sheet and expanded, You may provide only on one side. Further, the lead-antimony alloy layer may be provided only on the negative electrode lattice or on the upper and lower edges. FIG. 1 shows a cross section of the bone part of the negative electrode lattice when produced by expanding. Reference numeral 2 denotes a negative electrode lattice bone base material portion, and 4 denotes a lead-antimony alloy layer on the negative electrode lattice bone surface. The thickness of the alloy layer is arbitrary, and is determined by the thickness of the lattice alloy slab, the thickness of the lead-antimony alloy layer to be attached to the slab, and the sheet thickness after rolling. Generally, it is about 10-50 micrometers. The lead-antimony alloy layer contains 1% by mass to 10% by mass of antimony. If the content of antimony is less than 1% by mass, the idling stop life performance is improved only slightly at room temperature and high temperature. On the other hand, if the antimony content exceeds 10% by mass, it is difficult to produce a lead-antimony alloy foil. The lead-antimony alloy layer may contain a third component such as tin in a range of 10% by mass or less, for example.

  An active material paste is filled in each of the positive and negative electrode lattices and aged to obtain an unformed positive and negative electrode plate. The positive and negative electrode active material paste is a mixture of lead powder, additives, water and dilute sulfuric acid. Lead powder is a raw material mainly composed of lead oxide produced by a ball mill method or a Burton method. Positive electrode additives include short fibers such as acrylic and red lead, and negative electrode additives include lignin, carbon (carbon black, graphite, carbon fiber, expanded graphite, etc.), barium sulfate, and short fibers. The presence / absence of addition and the addition amount are arbitrary.

  The positive electrode plate and the negative electrode plate are alternately arranged via separators. As the separator, a microporous polyethylene separator is mainly used, but other microporous synthetic resin films such as polypropylene or a non-woven sheet of synthetic fibers may be used.

  The positive electrode plate and negative electrode plate are connected at their respective ears by the cast-on-strap method (COS method), burner welding method, etc., and the alloys used for connection are from the viewpoint of strength, vibration resistance, workability, etc. Lead-antimony alloys are mainly used, but lead-tin alloys and lead-calcium alloys may also be used.

  There are no particular restrictions on the method of containing aluminum ions and lithium ions in the electrolytic solution, and it may be added when the battery case is formed or after the battery case is formed. For example, lithium aluminate may be added, or aluminum sulfate and lithium sulfate, lithium carbonate, lithium hydroxide, or the like may be added in combination.

Manufacture of lead-acid batteries
N-55 type lead-acid storage battery (nominal voltage 12V, 5 hour rate rated capacity 48Ah) manufactured according to SBA S 0101 was manufactured. The positive electrode grid was prepared by processing a rolled alloy sheet (thickness: 1.0 mm) containing 0.07% by mass of calcium, 1.5% by mass of tin, and unavoidable impurities, with the balance being lead, by the rotary expanding method. The size of the positive grid is 115 mm in height, 100 mm in width, and 1.3 mm in thickness. The negative electrode grid is on one side of the position corresponding to the grid of the lead-calcium-tin alloy slab (thickness 13 mm) containing 0.05 mass% calcium, 0.5 mass% tin and unavoidable impurities and the balance being lead. Then, a sheet of lead-5 mass% antimony alloy foil (thickness 0.25 mm) was stacked, rolled and integrated to 0.8 mm, and processed by the rotary expand method. The negative electrode grid has a height of 115 mm, a width of 100 mm and a thickness of 1.0 mm, and the lead-antimony alloy layer has a thickness of about 15 μm.

  The positive electrode active material paste is a mixture of 99.9% by mass of ball powder lead powder 99.9% by mass and 0.1% by mass of acrylic fiber, mixed with 13% by mass of water and 6% by mass of dilute sulfuric acid with a specific gravity of 1.40 at 20 ° C. And produced. The negative electrode active material paste was 98.8% by mass of lead powder of ball mill method, 100% by mass of a mixture of 0.2% by mass of lignin, 0.3% by mass of carbon black, 0.6% by mass of barium sulfate, and 0.1% by mass of acrylic fiber. Then, 11% by mass of water and 7% by mass of dilute sulfuric acid having a specific gravity of 1.40 at 20 ° C. were mixed to obtain a negative electrode active material paste. Filled with 55g of active material paste per positive grid and 52g per negative grid, aged for 48 hours at 50 ° C and 50% relative humidity respectively, then dried in a dry atmosphere at 50 ° C for 24 hours. A positive and negative electrode plate was obtained.

  The negative electrode plate was accommodated in a separator made of a bag in which a microporous polyethylene sheet was folded in half and both ends were mechanically sealed. Seven positive electrode plates and eight negative electrode plates accommodated in a separator were alternately laminated, and lattice ears of the same polarity were welded by the COS method to form an electrode plate group. The obtained six electrode plate groups were housed in a polypropylene battery case and welded so as to be connected in series, and then the battery case and the lid were thermally welded to produce an unformed lead-acid battery. An N-55 type lead-acid battery was formed by injecting an electrolyte solution containing a predetermined amount of aluminum sulfate and lithium sulfate into dilute sulfuric acid with a specific gravity of 1.230 at 20 ° C and forming a battery case in a 25 ° C water tank. . A comparative example (sample A12) in which antimony was contained in the negative electrode active material instead of the surface of the negative electrode lattice was also produced. The amount of antimony added to the negative electrode active material is 300 ppm by mass, and the content of antimony per negative electrode is almost the same as that of a 15 μm thick lead-5 mass% antimony alloy layer on the surface of the negative electrode lattice. I tried to become.

For the lead storage battery of the test method example and the lead storage battery of the comparative example, the idling stop life test (SBA S 0101: 9.4.5 of 2006) is conducted as specified at room temperature of 25 ° C, and in the summer and high temperature areas Corresponding to the atmosphere in the engine room when driving a car for a long time, the test was conducted even at a high temperature of 60 ° C.

Results The results are shown in Tables 1 to 3 and FIGS. The result is a relative value in which the result of Comparative Example A6 is 100, which includes a lead-antimony alloy layer of lead-5 mass% antimony, contains 0.1 mol / L of sodium ions, and does not contain lithium ions and aluminum ions. displayed. The idling stop life performance is represented by a relative value of the number of cycles until the lead-acid battery reaches the end of life, and is represented as a normal temperature life cycle number and a high temperature life cycle number. This comparative example corresponds to the lead storage battery of Patent Document 1. The results are rounded to one decimal place, the number of samples is 3, and the results are shown as average values.

  Table 1 shows the presence / absence of a lead-antimony alloy layer on the surface of the negative electrode lattice and the influence of sodium ions, lithium ions, and aluminum ions in the electrolytic solution. When the lead-antimony alloy layer of the negative electrode lattice was missing, high life performance was not obtained even when the composition of the electrolyte was changed. On the other hand, when a lead-antimony alloy layer was provided on the surface of the negative electrode lattice, the room temperature life performance reached a practical level (Sample A6). However, the life performance at high temperatures is insufficient, and it is necessary to improve the relative value to 150 or more. Therefore, starting from sample A6, the high-temperature life performance was improved.

  When lithium ions (sample A7) or aluminum ions (sample A8) were added instead of sodium ions in the electrolyte, both room temperature performance and high temperature life performance were improved. Furthermore, when both lithium ions and aluminum ions were added (Sample A9), the high-temperature life performance was remarkably improved, and a lead-acid battery with practical performance for an idling stop vehicle was obtained.

  When the electrolyte solution contained 0.1 mol / L sodium ion, only an unsatisfactory high-temperature life performance could be obtained even if it contained the same amount of lithium ion and aluminum ion as sample A9 (sample A11). In addition, even when 0.1 mol / L sodium ion and 0.05 mol / L aluminum ion were contained, only unsatisfactory high-temperature life performance was obtained (Sample A10).

  When antimony was contained in the negative electrode active material instead of the lead-antimony alloy layer (Sample A12), the sulfation progressed rapidly and the number of life cycles at high temperature was insufficient. This indicates that antimony in the negative electrode active material and antimony on the surface of the negative electrode lattice are different in behavior, which means that antimony on the surface of the negative electrode lattice deteriorates the charging efficiency of the negative electrode active material. Although the sulfation is suppressed by improving the charge acceptance, the antimony in the negative electrode active material can be estimated to improve the charge acceptance of the negative electrode active material, although the charge acceptance is improved.

  The reason why sodium ion hinders the improvement of high-temperature life performance is unknown, but it has an interaction with antimony on the surface of the negative electrode lattice and suggests that it has the property of diffusing and precipitating antimony into the negative electrode active material. ing. Aluminum ions are known to suppress sulfation. In addition, the inventor has confirmed in a separate test that lithium ions improve high rate discharge performance. Characteristic in Table 1 is that the life performance at high temperature is improved by containing both aluminum ions and lithium ions.

  From Table 1, it is possible to provide a lead-antimony alloy layer on the surface of the negative electrode lattice, and to reduce the sodium ion content and to contain lithium ions and aluminum ions with respect to the electrolyte solution at room temperature or high temperature. It can be seen that the idling stop life performance can be improved. The influence of each of these elements is shown in Tables 2 and 3, and the same data is shown in FIGS.

  Table 2 and FIG. 2 show the influence of the antimony content in the lead-antimony alloy layer, and it can be seen that when the antimony content is 1% by mass or more, the life performance, in particular, the life performance at a high temperature is improved. Further, since it is difficult to produce an alloy foil when the antimony content exceeds 10% by mass, the upper limit of the antimony content is set to 10% by mass.

  The upper part of Table 3 and FIG. 3 show the influence of the sodium ion content in the electrolyte. When the sodium ion content exceeds 0.04 mol / L, the life performance, particularly at high temperatures, is significantly reduced. It can be seen that the effect of sodium ion is constant at 0.02 mol / L or less.

  The middle part of Table 3 and Fig. 4 show the influence of the lithium ion content in the electrolyte. The life performance at high temperature is improved at 0.02 mol / L or more, the improvement is remarkable at 0.05 mol / L or more, and 0.2 mol / L. It can be seen that the high temperature life performance deteriorates when the temperature exceeds.

The lower part of Table 3 and Fig. 5 show the influence of the aluminum ion content in the electrolyte. The life performance at high temperature and room temperature is improved at 0.02mol / L or more, and high at 0.05mol / L to 0.2mol / L. It can be seen that the life performance is particularly improved.

2 Negative electrode lattice part base part 4 Lead-antimony alloy layer

Claims (5)

A lead-acid battery comprising a negative electrode plate, a positive electrode plate, and an electrolyte that immerses the negative electrode plate and the positive electrode plate,
The lattice frame of the negative electrode plate is provided with a lead-antimony alloy layer on at least a part of the surface,
The said electrolyte solution is a lead acid battery containing a lithium ion and an aluminum ion. A lead-acid battery comprising a negative electrode plate, a positive electrode plate, and an electrolyte that immerses the negative electrode plate and the positive electrode plate,
The lattice frame of the negative electrode plate is provided with a lead-antimony alloy layer on at least a part of the surface,
The lead acid battery characterized in that the electrolyte contains lithium ions and aluminum ions, and the content of sodium ions is 0.04 mol / L or less.   3. The electrolytic solution according to claim 1 or 2, wherein the electrolytic solution contains lithium ions of 0.02 mol / L or more and 0.2 mol / L or less and aluminum ions of 0.02 mol / L or more and 0.2 mol / L or less. Lead acid battery.   The lead acid battery according to any one of claims 1 to 3, wherein the antimony content of the lead-antimony alloy layer is 1 mass% or more and 10 mass% or less.   An idling stop vehicle comprising the lead acid battery according to any one of claims 1 to 4.