JP2001126735A - Lead storage battery - Google Patents

Abstract

(57) [Abstract] [Problem] To suppress the elongation of a lattice body made of a lead-calcium alloy and to prolong its life. SOLUTION: In a lead-acid battery using a lead-calcium-based alloy for a positive electrode grid, 1 / in the height direction of the positive electrode grid.
The members (horizontal bars 2A, B) that maintain the lateral strength except for the frame bone 1 of the lattice body located below 2 have a cross-sectional area of 1 in the height direction.
/ 2 compared to the cross-sectional area of the member (horizontal bar 2C) that maintains the lateral strength excluding the frame bones of the lattice body located above / 2
Increase by more than%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead-acid battery, and more particularly to a lead-acid battery using a lead-calcium alloy for a positive electrode grid body and having improved life performance.

[0002]

2. Description of the Related Art Conventionally, lead-calcium alloys and lead-antimony alloys have been used as materials for forming a positive electrode grid of a lead-acid battery.
Compared to a lead-antimony alloy, when used under a float charge for a long time, remarkable elongation occurs due to lattice corrosion, so that it has a drawback that the life performance particularly at high temperatures is significantly inferior. On the other hand, lead-antimony alloys include
There is a problem that the electrolyte-reducing property is inferior to that of a lead-calcium alloy, which is disadvantageous from the viewpoint of maintenance-free.

Therefore, various proposals have been made to improve the life performance of a positive electrode grid body using a lead-calcium alloy having excellent liquid reducing properties. For example, the compression ratio of the separator is increased, or
As disclosed in JP-A-99-99, there is known a method in which the cross-sectional area of the vertical bone of the lattice frame is set to be at least twice as large as that of the horizontal bone and the compression ratio of the separator is increased to suppress the elongation.

[0004]

For example, Japanese Patent Application Laid-Open No.
As described in Japanese Patent Application Laid-Open No. 0-188999, it is possible to delay corrosion deterioration by increasing the cross-sectional area of the vertical bones of the lattice frame, but the ultimate elongation of the lattice bones becomes large, and the active material coated on the lattice body is increased. There is a tendency that the material pace detaches from the lattice bone and shortens the life.

[0005] It is also necessary to increase the compression ratio of the separator.
It is possible to suppress lattice bone elongation and paste detachment
However, by increasing the compression ratio, the
Because the downward circulation is obstructed, the specific gravity difference,
The stratification of the lysate tends to be remarkable. Stratified like this
Under the electrolyte, the lower part of the lattice is in contact with the denser electrolyte than the upper part.
And the discharge reaction of the active material in the lower region is easy.
And the lower PbSO _FourThe amount increases. Meanwhile, charging reaction
Conversely, when the active material fills the upper region in contact with the dilute electrolyte,
The PbSO in the lower region is_Four
Consumption is reduced. By repeating charge and discharge,
The non-uniform active material reaction proceeds above and below the lattice.
As a result, the progress of grid corrosion and the
Quality desorption occurs remarkably, and life performance is remarkable
The problem is that it is reduced to a point.

[0006] In the case of a lead storage battery for an automobile, no gas is generated while the vehicle is mounted on the vehicle in order to prevent the battery fluid from decreasing.
Float charging was performed at a constant voltage of about 4 to 15 V, the layer was more likely to be stratified, and the active material use efficiency of the positive electrode grid body was likely to be uneven in the plane.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a lead-acid battery capable of achieving a long life comparable to that of a lead-antimony alloy while maintaining good liquid reduction properties of the lead-calcium alloy. .

[0008]

That is, the present invention provides lead-
In a lead-acid battery using a calcium-based alloy for the positive electrode grid, in the height direction of the positive electrode grid, the cross-sectional area of a member that maintains lateral strength excluding the frame bone of the grid located below 1/2, The lead-acid battery is characterized in that it is expanded on average by 5% or more in comparison with the cross-sectional area of the member maintaining lateral strength excluding the frame bones of the lattice body, which is located above 上 in the height direction. It is about.

The present invention also provides a positive electrode plate in which an active material is filled in the positive electrode grid, and a negative electrode plate which are alternately arranged, and a non-woven fabric of insulating fibers is interposed between the positive electrode plate and the negative electrode plate. The present invention also relates to a lead-acid battery, wherein the electrode plate group is inserted into a battery case with a compression force of 2 to 80 kPa.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a positive grid is
Any of a radial type manufactured by a continuous casting method as shown in FIG. 1 and an expanded type shown in FIG. 2 may be used. FIG.
In the radial type, the horizontal rail 2 and the vertical rail 3 are arranged in a frame 1 having a connection ear 4, and in this example, the vertical rail 3 is arranged radially with respect to the connection ear 4 in order to increase current collection efficiency. But is not limited to this. The expanded type shown in FIG. 2A has an expanded portion 5 between the frame 1 provided with the connection ear 4 and the lower frame 1 '.
2B and 2C are partial enlarged views of D and E in FIG. 2A, respectively.

[0011] The "member maintaining the lateral strength of the lattice body"
In the radial type lattice body as shown in FIG. 1, it means the horizontal rail 2 and does not include the frame 1. In the expanded lattice body shown in FIG. 2, all of the expanded portions 5 correspond. The “cross-sectional area” is the area of the cross-section in the short axis direction of the horizontal rail 2 shown in FIG.
As shown in the partial enlarged views (b) and (c), x in the lattice skeleton 6 connecting the intersections 7
It means the area of the cross section along the -x 'and yy' lines or the vertical cross section (X, Y) of the intersection 7.

Further, "on average" means, for example, in the case of the radial type shown in FIG. 1, (1) the upper half horizontal rail 2 is made up of one having a certain thickness (longitudinal section) and the lower half horizontal rail 2 that is enlarged by 5% or more in cross-sectional area;
Can be adopted such that the cross-sectional area is gradually or stepwise enlarged from top to bottom, and the vertical cross-sectional area of the horizontal rail above and below 1/2 in the height direction is increased on average.
In addition, in the expanding type shown in FIG. 2, the slit width at the time of expanding is changed to enlarge in the same manner as in the radial type, and the thickness of the original plate used for expanding is changed at the upper and lower portions to keep the slit width constant. Alternatively, any method such as a method of changing and developing may be used. In any case, it goes without saying that sufficient strength is obtained at the minimum cross-sectional area.

The "lead-calcium alloy" in the present invention is a material well known in the art, and includes an alloy obtained by adding a trace amount of calcium to lead, and further adding tin in addition to calcium.

The effect can be obtained if the width of the cross-sectional area is 5% or more. However, if the width is too large, the retention characteristics of the active material deteriorate. Therefore, the upper limit is about 70%. Preferably 10-5
It is desirable to enlarge in the range of 0%.

By using the positive electrode grid body thus formed, the corrosion strength of the lower half in the height direction can be improved, and the lattice elongation can be suppressed. As a result, even in the case where the electrolyte solution is used under conditions in which stratification occurs, it is possible to effectively suppress the progress of lattice corrosion and shortening of the life due to active material desorption.

In order to form a lead-acid battery using the grid thus formed, a conventionally known method can be adopted. The positive grid is filled with an active material paste containing lead oxide to form a positive electrode plate.
The positive electrode plate and the negative electrode plate are alternately arranged via a separator to form an electrode group, and the electrode group is inserted into a battery case,
Then, a predetermined lid material is adhered to the opening of the battery case, an electrolytic solution is injected into the battery case, and a chemical conversion treatment is performed to obtain a sealed lead-acid battery. In addition, a conventionally well-known material can be used for the active material paste, the negative electrode plate, the separator, and the like.

In the present invention, when forming an electrode plate group from a positive electrode plate and a negative electrode plate, a non-woven fabric made of an insulating fiber material such as a glass mat is sandwiched between the positive electrode plate and the negative electrode plate. Force 2 to 80 kPa, preferably 5 to 50 kP
By inserting the positive electrode into the battery case as a, the elongation of the positive electrode grid and the desorption of the active material can be more effectively suppressed.
The insulating fiber material may be any material that is resistant to an electrolytic solution, and glass fibers typified by glass mats are preferable because they are inexpensive and easily available. The glass mat may be manufactured by a standard method, but is a glass fiber having an average fiber diameter of 1 micron or less in order to secure a diffusion path so as not to hinder the vertical circulation of the electrolyte under pressure. Is preferred.

The electrode group may be inserted into the battery case under a predetermined pressing force using a jig. The electrode group inserted into the battery case is in a state where a compressive force is constantly applied by the outer wall of the battery case.

[0019]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1 By a continuous casting method, lead-calcium (Pb-
A radial lattice made of 0.06 mass% Ca) was produced. At this time, the cross-sectional area of the horizontal rail 2 (A and B) located in the lower half of the lattice body was 3 mm ^2, and the cross-sectional area of the horizontal rail ² (C) located in the upper half was 2.25 mm ^2. A was gradually expanded to A, and the horizontal rail located in the lower half was expanded by about 30% with respect to the horizontal rail located in the upper half on average. This grid body was filled with a paste-like active material to form a positive electrode plate, which was combined with a negative electrode expanded grid body manufactured by a usual method to form an electrode group, thereby constituting a B19 type lead storage battery (initial electrolyte amount: 2500 g). .

Example 2 In forming an electrode group using the positive electrode plate manufactured in the same manner as in Example 1, an electrode group was formed by sandwiching a glass mat between the negative electrode plate and the electrode group. It was inserted into the battery case with a compression force of 5 kPa to form a B19 type lead storage battery.

Comparative Example 1 A B19 type lead-acid battery was constructed in the same manner as in Example 1 except that the cross-sectional area of the cross rail ² was all uniform at 1.21 mm ² to form a positive electrode grid.

Comparative Example 2 The cross-sectional area of the crosspiece was uniform (x-x ') by the expanding method.
Cross-sectional area: 1.69mm ^Two) Lead-calcium (Pb-
0.06 mass% Ca) to produce an expanded lattice
Was. This grid body is filled with a paste-like active material, and the positive electrode plate and
Then, in combination with the same negative electrode plate as in Example 1, B19 type
A lead storage battery was constructed.

Comparative Example 3 A lead-antimony (Pb-1.7% by mass Sb) radial lattice having a uniform cross-sectional area of a bar was manufactured by a continuous casting method, and the lattice was filled with a paste-like active material. A B19 type lead-acid battery was formed by combining the negative electrode plate as in Example 1 with the positive electrode plate.

Light Load Life Test Regarding the lead storage batteries manufactured in the above Examples and Comparative Examples,
A 75 ° C. light load life test (SAE life test) was performed according to JIS D-5301-1991. The life was determined when the terminal voltage reached the starting failure limit. Further, the liquid reduction characteristics at the end of the life were also measured. Table 1 shows the results. The SAE of Example 2, Comparative Example 2, and Comparative Example 3
Life test progress (change in terminal voltage with respect to cycle number)
Is shown in FIG.

[0026]

[Table 1] Comparison of battery performance

As is apparent from Table 1, in the embodiment according to the present invention, the cycle life was remarkably improved while maintaining high liquid reduction characteristics. In particular, the electrode plate group was formed with a glass mat interposed therebetween. Example 2 inserted into battery case under predetermined compression
As a result, a cycle life comparable to that of the lead-antimony system (Comparative Example 3) could be achieved.

[0028]

According to the present invention, a dramatic improvement in the life performance can be achieved while using a lead-calcium alloy for the positive electrode grid. Further, the advantage of the present invention is extremely high because the advantage of excellent liquid reduction properties can be maintained as it is.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a positive electrode grid formed by a continuous casting method.

FIG. 2 is a schematic view illustrating a positive electrode grid formed by an expanding method, wherein (b) and (c) are each (a).
3 is a partially enlarged perspective view of D and E in FIG.

FIG. 3 is a graph showing a change in terminal voltage with respect to a use cycle of the lead storage batteries manufactured in Example 2 and Comparative Examples 2 and 3.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Frame 2 Horizontal bar 3 Vertical bar 4 Connection ear 5 Expanding part 6 Lattice bone part 7 Intersection part

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference)

Claims (2)

[Claims] 1. A lead-acid battery using a lead-calcium alloy for a positive electrode grid, wherein 1 /
The cross-sectional area of the member that maintains the lateral strength excluding the frame bone of the lattice body located below 2 maintains the lateral strength excluding the frame bone of the lattice body that is located above 1/2 in the height direction. A lead-acid battery characterized by being expanded on average by 5% or more compared to the cross-sectional area of the member. 2. An electrode plate in which a positive electrode plate in which an active material is filled in the positive electrode grid and a negative electrode plate are alternately arranged, and a non-woven fabric of insulating fiber is sandwiched between the positive electrode plate and the negative electrode plate. Group
The lead-acid battery according to claim 1, wherein the battery is inserted into the battery case with a compression force of 2 to 80 kPa.