JPH02170939A - Lead alloy for storage battery - Google Patents

Abstract

PURPOSE:To prolong the service life of a battery at the time of use by deep charge and discharge by specifying the composition of a low-Sb alloy containing As, Sn, Cu, and S. CONSTITUTION:This lead alloy tor storage battery has a composition consisting of, by weight, 1.3-2.5% Sb, 0.05-0.4% As, 0.06-0.09% Sn, 0.005-0.1% Cu, 0.001-0.03% S, and the balance Pb. Since the occurrence of casting cracks is prevented in this lead alloy because of its fine crystalline grains, a battery in which a grid made of this lead alloy is used has superior maintenance free characteristic and also has long service life even if used by deep charge and discharge. In the above lead alloy, As is effective in improving corrosion resistance and mechanical strength and it is necessary to regulate As content to the lower limit or above, but the above effect is saturated when it exceeds the upper limit. Sn is effective in improving the flowability of molten metal and it is necessary to regulate Sn content to the lower limit or above, but workability is deteriorated when it exceeds the upper limit. Cu is effective in accelerating the refining action of S and it is necessary to regulate Cu content to the lower limit or above, but the amount of self-discharge is increased when it exceeds the upper limit. Further, S is effective in refining crystalline grains and has a function of preventing the occurrence of cracks, and it is necessary to regulate S constant to the lower limit or above, but it is difficult to add it by the amount exceeding the upper limit.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to the improvement of 59(r)b> alloy for Ti batteries. In particular, the crystal grains of lung alloy with low antimony (sb) content are made fine and its As a result, the occurrence of casting cracks is prevented, corrosion resistance is improved, and work during tin manufacturing is facilitated.

Conventional technology and its challenges Traditionally, bell parts such as lead-acid battery grids and pouching
(containing 54.5 to 8 weight percent)-3 series alloys have been used. In this case, S is added to pure lead, which is originally very soft and unsuitable for grids for lead-acid batteries or lead parts, in order to provide mechanical strength and improve castability. However, 3 is expensive, and as the 9 content increases, the amount of self-discharge of the lead-acid battery increases.

Therefore, attempts have been made to reduce the content of 3 in lead acid battery grids or lead bacteria as much as possible. but,
If the 9 content was simply reduced, cracks would occur during B manufacturing, and a good product could not be obtained. Japanese Unexamined Patent Publication No. 58-18
In the inventions described in JP-A-5739 and JP-A-59-37660, arsenic (As) and tin (C) are used.

Low 3 alloys containing ff1 (Cu), sulfur (S), etc. and having sb contents of 0.1-1.2% and 036-1%, respectively, have been proposed. Although batteries using grids made of these alloys have excellent maintenance-free characteristics,
When subjected to deep charge/discharge use. The drawback was that it had a relatively short lifespan.

Means for Solving the Problems The present invention provides St+ 1.3 to 2.5% by weight, 0.05 to
0.43i amount%, Sn0.06 λ0.09 weight%,
Cu0.005-0.1% by weight, 5O1001-0.
This uses an alloy consisting of 0.3% by weight and the remainder, which makes the crystal grains finer, thereby preventing the occurrence of casting cracks, improving corrosion resistance, and facilitating work during casting. A battery using a grid can have a service life without any practical problems even when used for deep charging and discharging.

Example Hereinafter, the present invention will be explained in detail with reference to Examples.

A positive electrode lattice for an automobile battery having the alloy composition shown in Table 1 was produced by the normal gravity 5JJ manufacturing method, and Pb-Ca-Sn
A rolled alloy sheet was assembled with a negative electrode grid obtained by expanded processing, and charged in a conventional manner.
I used an 8^h battery. Next, these batteries were subjected to a life test according to 305301, which is an example of a deep charge/discharge cycle. The results are shown in Table 1.

Note that the number of lifetimes in the table is shown with the number of lifetimes of the battery using the N011 alloy as 100. Also, in the same table, JI
The result of the liquid reduction characteristic test described in the explanation section of S05301 (the amount of liquid reduction of the battery using alloy No. 1 was 100
) are also shown.

Table 1 As is clear from Table 1, the alloy according to the present invention (NO,
In batteries using 3 to 140.6), the lifespan under deep charging and discharging is the same, or at worst 70%, compared to conventional alloys with a high sb content <NO, 1, NO, 2). Ori,
In practice, there is no problem. Furthermore, the amount of liquid reduced is 1/2 compared to conventional products.
It can be seen that the maintenance-free characteristics have been significantly improved, which is 72-1/3. Although the product with even lower Sb content (No. 7N0.8) has a significantly improved liquid reduction amount of about 175 compared to the conventional product, the life cycle is less than half that of the conventional product, which poses a practical problem. .

The alloy of the present invention contains fis, Sr+, QI, and S in the 5 elements, and the roles of these elements are as follows.

Improved corrosion resistance and mechanical properties! However, if it is less than 0.05%, there is almost no effect, and if it is more than 0.4%, the effect is almost saturated, resulting in waste and increased costs. It only becomes a factor.

Sn is effective in improving latent flow, but if it is less than 0.06%, the effect is not seen. Moreover, if the amount is more than 0.09%, it is not preferable because it becomes sticky near the 9+ days of drying and reduces workability.

Addition of a small amount of O has the effect of promoting the 1fi4 reaction of S, which will be described later. However, if the amount is less than 0.005%, this effect is not observed, while if it exceeds 0.3%, the The amount of discharge increases, which goes against the intention of improving maintenance-free characteristics.

S is effective in refining crystal grains. When 9 is reduced, crystal grains generally become coarser, cracks are more likely to occur during casting, and it becomes difficult to obtain a sound lattice.

S makes such coarse crystal grains fine and prevents the occurrence of cracks, and adding a small amount of α further promotes this effect. At this time, if S is less than 0.001%, no effect will be seen. t, under normal casting conditions, O.03%
It is also difficult to add more.

Lead recycled from waste electrode plates or used lead-acid batteries, so-called waste lead, may be used as the grid alloy.

In addition to the above-mentioned elements, such lead contains bismuth (B1),
Although a trace amount of silver (A9) etc. may be contained, even if such lead is used, the effects of the alloy according to the present invention described above will not change.

In addition, this time we showed an example applied to automobile batteries, but electric vehicle batteries (paste type) and forklift batteries (forklift batteries), which require deeper charging and discharging than automobile batteries, are also shown.
It goes without saying that the alloy according to the present invention can also be applied to the cladding type. Under these conditions, conventional products lose a large amount of liquid and require a lot of manpower and time to replenish water. However, by using the alloy of the present invention, it is possible to significantly reduce and reduce the size.

Effects of the Invention As detailed above, the use of the alloy according to the present invention makes the crystal grains finer, thereby preventing the occurrence of casting cracks, improving corrosion resistance, and facilitating the work during casting. Batteries using grids made of this alloy not only have excellent maintenance-free characteristics, but also have a long service life without any practical problems even when used for deep charging and discharging, and their industrial value is extremely high. big.

Claims (1)

[Claims] 1. Antimony 1.3~2.5% by weight, arsenic 0.05~
0.4% by weight, tin 0.06-0.09% by weight, copper 0.0
1. A lead alloy for storage batteries characterized by comprising: 0.05 to 0.1% by weight of sulfur, 0.001 to 0.03% by weight of sulfur, and the balance lead.