JPS603855A - Alkaline zinc storage battery - Google Patents

Abstract

PURPOSE:To suppress the deterioration of the performance of an alkaline zinc storage battery and the deterioration of the strength of a separator by using a microporous polypropylene film as a separator touching the negative electrode and a woven fabric, a nonwoven fabric or mixture paper made of vinylon fiber or cellulose-system fiber as a separator touching the positive electrode. CONSTITUTION:In an alkaline zinc storage battery, the amount of electrolyte is restricted so that no liberated electrolyte practically exists and the amount of the electrolyte contained in a separator touching a negative electrode is smaller than that contained in a separator touching a positive electrode. In such a battery, the separator is formed by putting a microporous polypropylene film 3 and a nonwoven vinylon fabric 4 upon each other so that a zinc electrode 1 touches the microporous polypropylene film 3 and a nickel electrode 2 touches the nonwoven vinylon fabric 4. As a result, drying of the surface of the separator is suppressed. Besides, the deterioration of the strength of the separator caused due to concaves and convexes formed on the surface of the zinc electrode as cycles proceeds as well as retention of the electrolyte or gas in the concave areas are suppressed. Consequently, the performance of the battery is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of application of PCC The present invention relates to alkaline zinc storage batteries using zinc as a negative electrode active material, such as nickel-curved lead storage batteries, silver-zinc storage batteries, and the like.

(b) The conventional alkaline qIi lead-acid IT canopy has the advantages of high energy density, high operating voltage, and good low-temperature characteristics, as well as excellent economic efficiency and safety. However, it has the disadvantage of short cycle life due to charging and discharging. This drawback is that zinc in the negative electrode dissolves as zincate ions in the electrolyte during discharge, and during charging, dendritic or cotton-like formations occur on the negative electrode surface. This is caused by lead precipitating and penetrating the separator, causing a short circuit (1μ) or deformation of the negative electrode.
Through various improvements such as tubes, electric FTV liquid, and separate lakes, l
Attempts have been made to overcome the drawbacks described above.

One way to overcome this drawback is to focus on the fact that the more the PJ liquid is present in the supercharge, the more the production of zincate ions is promoted. 1i1 [An electrolytic solution in which the electrolytic solution is in an amount such that no one in the L state exists and is in contact with the zinc negative electrode through a plurality of separators between the two electrodes.] is in contact with the positive electrode. There is a method of configuring the amount to be less than the amount of liquid.

Although this method is excellent in removing excess electrolyte on the surface of the zinc negative electrode and improves cycle life, it often has the following drawbacks depending on the structure of the separator.

For example, if a multilayer separator is constructed by using a microporous polypropylene film as the separator in contact with the zinc negative electrode and a nylon nonwoven fabric as the separator in contact with the positive electrode to increase the electrolyte gradient toward the positive electrode, the polypropylene film Since it is hydrophobic, as the cycle progresses, the hydrophilicity deteriorates and the surface becomes dry, increasing the internal resistance of the battery, and as the cycle progresses further, 11! Lead negative electrode surface curved and dendritic or n'σ cotton-like! 1] When engineered lead begins to precipitate and unevenness forms on the negative electrode surface, does it become a concave part? Li solution j1 Riyakasu is bent? (h) The separator properties θ3 are deteriorated, and since the separator is pressed by the convex portion, the strength of the separator rapidly deteriorates in the pressed portion.

(／→ Purpose of Development The present invention has been developed in view of the above points, in which the amount of electrolyte in the separate lake in contact with the negative electrode is reduced to the level in which the amount of electrolyte in the separate lake in contact with the positive electrode is The purpose of the present invention is to suppress the deterioration of the battery performance and the strength deterioration of the middle pallet in an alkaline zinc shield battery configured such that the amount of electrolyte is smaller than the amount of electrolyte.

2)) Structure of the Invention The present invention comprises at least one negative electrode, at least one positive electrode, a multilayer separator disposed between these two electrodes, and a zinc that is absorbed in the two electrodes and the separator and exists in the form of substantially free zinc. Add 1 ml of alkaline electrolyte to the level of rubbing.
] The separator in contact with the negative electrode is a microporous polypropylene film layer, and the separator in contact with the positive electrode is vinyl U fiber A.1 [or a woven fabric made of cellulose fiber, a non-woven fabric, or a blend of these fibers This is an alkaline zinc storage battery configured so that the amount of electrolyte in the separator in contact with the negative electrode is smaller than the amount of electrolyte in the separator in contact with the positive electrode by using papermaking.

(e) Compare the missing example of the example tree i', l; Ill (shown and explained below along with K example).・Figure 151 and Figure 6 h ↓ One example of wood starting j and other examples r, nickel-zinc of H section example,
'r';ji<ike no iy'gt u+8 explanatory diagram, Figure 2 is a comparative example of nickel 'Ili fi'i:1 accumulation'
It is a schematic explanatory diagram of Kazuya Ichi.

As an embodiment of the present invention, as shown in FIG. 1, the separator is made of a two-layer structure consisting of a microporous polypropylene film (3) and a vinylon nonwoven fabric (4).
1) and microporous volip [1 pyrene film '31, and nickel 11? In the ladder KL where 121 and the vinylon nonwoven fabric 14) are in contact, the height is set to such an extent that virtually no free material exists. Do you understand? l
It's time to finish the game! "1.: Create a trap by making a nickel-11 lead acid battery of 4 AH. Let this 4711) be A.

- As shown in Figure 2, a 4AH nickel-zinc storage battery was fabricated with the same configuration except for the Hinilon non-woven fabric (5) in the configuration of the previous example, as shown in Figure 2. In the above example, the vinylon nonwoven fabric was replaced with cellophane (6), and a separate layer laminated with microporous polypropylene film +31 and Shichironon (6) was used, the other configurations were the same, and the capacity was 4.
A nickel-41+lead acid battery 1 of AH was prepared and designated as battery C.

Using the batteries A to C prepared in this way, they were charged for 4 hours and 30 minutes at a current of 1A. A cycle test was conducted under the cycle conditions of discharging at a current of fj L and 1A for 4 hours.

This connection W is shown in FIG. 4 as a cycle characteristic diagram. From FIG. 4, it can be seen that the finished J battery A has superior characteristics compared to the comparative battery B, and the comparative battery C has extremely inferior characteristics compared to the invention battery A and the comparative battery B. The reason for this is thought to be as follows.

First of all, the reason why the J battery A produced by the present invention showed superior characteristics to the comparative battery B is that the nonwoven fabric made of cellulose fibers and vinylon fibers in contact with the positive electrode has high hydrophilicity and liquid retention properties, which increases the initial battery capacity and battery voltage. As the cycle progresses, the fibers of the non-woven fabric become loose, increasing its synthetic properties, and preventing deterioration of battery performance due to drying of the surface of the microporous polypropylene film. Even when pressed, the nonwoven fabric layer in the pressed area deteriorates and moves to the part where the pressure cannot be removed, that is, the part corresponding to the concave part of the lead electrode surface, so the pressing force is absorbed by 1. This suppresses the strength deterioration of the separator, and the transferred cellulose fibers and vinylon fibers press the microporous polypropylene film against the recesses on the surface of the zinc electrode, filling the recesses and allowing the electrolyte to flow. This is thought to be due to the prevention of dirt and debris from flowing into the concave portions and deteriorating battery performance.

Also, the comparative battery C has extremely inferior characteristics compared to the battery A and the comparative battery B of the present invention.The reason why the characteristics of the comparative battery C are extremely inferior to that of the battery A and the comparative battery B is that when a film-like material such as Nanaronon is placed on the positive electrode side, the gas generated from the positive electrode is The reason for this is that the electrode reaction area decreases as the removal accumulates between the electrodes.Thus, even though the cellulose yarn is the same, film-like cellophane has poor properties.Woven fabrics and non-woven fabrics using rayon of fiber A. will improve.

In addition, as another embodiment of the present invention, ε (' As shown in Fig. 1) and microporous polypropylene film (3)
) and the nickel electrode (2) and the vinylon nonwoven fabric (4) are in contact with each other to make the battery more effective.

(f) Zero effect of the invention] has an electrolytic solution limited to such an extent that no free substance is substantially present, and the amount of electrolytic solution in the separator in contact with the negative electrode is smaller than the amount of electrolytic solution in the separator in contact with the positive electrode. In an alkaline zinc storage battery configured to ...The surface of the rake dries, and as the cycle progresses, the surface of the lake dries.
The strength deterioration of the separator due to the irregularities on the surface of the zinc electrode and the accumulation of electrolyte and gas in the concave parts were suppressed, and
11. It has the effect of further improving sex.

4. Drawing 1) iflrli- explanation j? Fig. 151 and No. 51: ', I tyomotoyari J's - 2 no r τ111<t+) showing a giant example and another example is a specific yield example of nickle zinc,
``11den/lu, no 4)! to Fl; 5!!'1gl
-1l1 figure, near+, 4 figure 1-J, cyc/l/4
This is a 4r sex diagram.

(1)...Zinc forest, (2)...Nickel bustle, (,3)
... nFk porous polypropylan film, +51・
...Nylon non-AV & 75.14)...Nylon non-Th' to cloth, (6)...Seronon.

Out 1chi 1. I 1 person Sanyo Sora 1 machine Co., Ltd. ・':,': ,
'(,:l.

, 41 Representative Patent Attorney Shizuo Sano - Yuno Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] (1) At least one zinc negative electrode, at least one positive electrode, and a multilayer separator disposed between these two electrodes to the extent that zinc is absorbed by these two electrodes and the separator, and substantially no free zinc is present;) ; By using a mixed paper made of these fibers, a microporous polypropylene film is used as the separator in contact with the negative electrode, and the electrolytic liquid in the separator in contact with the negative electrode becomes rifJ. An alkaline zinc storage battery characterized in that the amount of electrolyte is smaller than the amount of electrolyte in the separate electrode in contact with the positive electrode.