JP2985335B2 - Electrode - Google Patents

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 electrode.

[0002]

2. Description of the Related Art In general, a lead-acid battery in which a grid or a porous body is coated with a paste to form an electrode is composed of lead oxide, water, sulfuric acid,
Fibers and the like are mixed and kneaded to form a paste. This paste is applied to a grid or a porous body and dried to form electrodes. Thereafter, this electrode is oxidized or reduced in a step called chemical formation to form positive and negative electrodes. Such a lead-acid battery electrode manufactured by the process receives a physical impact during the manufacturing process, a physical impact in use after the manufacturing, and a stress strain due to charging and discharging. The conventional kneading and drying conditions have been optimized for these impacts or strains to improve the adhesion between the active materials and the adhesion between the lattice and the active material, and by adding fibers as a structural material doing. As the fiber used here, polypropylene fiber (PP), acrylic fiber, glass fiber, carbon fiber, and the like have been conventionally proposed. When selecting these fibers, the conditions to be considered were the affinity with water, the dispersion state during kneading, the shape and strength of the fibers, and the like. In addition to the selection of the type of fiber, for example, Japanese Patent Application Laid-Open No. 55-8606 proposes a method of improving mechanical strength by adding two or more types of fibers having different wire diameters to a paste.

[0003]

However, fibers conventionally used are merely used as structural materials, and exist only between active materials and do not have other functions. Therefore, when the active material shrinks, the active material and the fiber are easily peeled off, which may lead to the fall of the active material.
3A and 3B show a conventional product, in which FIG. 3A shows a state in which a paste is applied to a grid, and FIG. 3B shows a state after aging and drying. 2 is a lead oxide and 4 is a polypropylene fiber. In order to solve such a problem, the present invention improves the ability of the electrode to retain the active material by bonding between the fiber and the fiber and between the fiber and the active material. The purpose of the present invention is to provide an electrode which can prevent the occurrence of a problem and have excellent quality stability and a long life.

[0004]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a process for mixing lead oxide with water, sulfuric acid, fibers, etc., and kneading the fibers with an adhesive PVA.
The use of fibers or fibers coated with an adhesive resin is intended to improve the active material holding power of the electrode. FIG. 1 shows a product of the present invention, in which (a) shows a state where a paste is applied to a lattice, and (b) shows a state after aging and drying. 1 is an adhesive fiber, and 3 is an adhesive part.

[0005]

[Action] Currently used pastes are lead oxide, lead,
It is composed of tribasic lead sulfate and the like. These constituents change chemically during drying, and the bonding strength between the active materials is strengthened. As described above, in the present invention, in addition to this effect, a water-soluble adhesive PVA fiber or a fiber coated with an adhesive PVA is mixed at the time of kneading the paste, and the fiber-active material and the fiber-fiber are mixed with each other by 50-100. After aging in the range of ° C., the active material-fiber and the fiber-fiber are bonded to each other in the process to form a network structure of the fiber, thereby enhancing the active material holding power of the electrode.

[0006]

The present invention will be further described below with reference to examples. 1 kg of lead oxide, 90 ml of water, specific gravity of 1.26
The same amount of commercially available polypropylene fiber 4 was mixed and kneaded with 125 ml of sulfuric acid and 10 g of commercially available adhesive PVA fiber 1 (VPB105-2 manufactured by Kuraray Co., Ltd.) to obtain a paste. This is 141 (W) × 110 (H) × 1.6
A (t) mm lead alloy grid was filled, primary dried at 70 ° C. for 10 hours, and further dried at 120 ° C. for about 1 hour to prepare a pre-chemical conversion electrode weighing about 140 g. Thereafter, these plates were subjected to a physical property test, and the formed plates were subjected to a property test.
As a physical property test, the electrode plate was dropped six times from a height of 50 cm, and the ratio of the remaining active material was measured. As a result, in the conventional electrode plate to which polypropylene was added, the active material remaining rate was 50%,
It was 96% for the electrode plate to which the adhesive fiber according to the present invention was added. In the characteristic test, an N36B type battery was prototyped using these electrode plates, and a life test was performed at a charge of 5 A, a discharge of 20 A, and a temperature of 40 ° C. The result is shown in FIG.

[0007]

According to the present invention, an electrode plate having improved mechanical strength by adding fibers as a structural material, optimizing aging and drying conditions, etc., has a low strength before chemical conversion, and is handled in an assembly process. Had a problem. In addition, the charge-discharge cycle characteristics were low, and stable characteristics were difficult to obtain. In contrast, in the present invention, by adding a water-soluble adhesive fiber or a fiber coated with a water-soluble adhesive resin to the active material,
The active material-fiber and the fiber-fiber are bonded in an aging step.
Therefore, the strength of the unplated plate is significantly improved, and the effect of improving the charge / discharge cycle characteristics is also obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory view of the present invention.
(B) shows the state after aging and drying.

FIG. 2 is a comparative characteristic diagram of the present invention and a conventional product.

3A and 3B are explanatory views of a conventional product, wherein FIG.
(B) shows the state after aging and drying.

[Explanation of symbols]

 1 is an adhesive fiber, 2 is a lead oxide, 3 is a bonded portion

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-57-165967 (JP, A) JP-A-1-120760 (JP, A) JP-A-59-27458 (JP, A) (58) Field (Int.Cl. ⁶ , DB name) H01M 4 / 14,4 / 20 H01M 4/24-4/26 H01M 4/62

Claims (3)

(57) [Claims] 1. A lead-acid battery in which a paste is applied to a lattice or a porous body, wherein the paste contains adhesive fibers or fibers coated with an adhesive resin. 2. The adhesive fiber or the adhesive resin is 5 degrees Celsius.
The electrode according to claim 1, wherein the electrode is water-soluble in a range of 0 to 100 degrees. 3. The adhesive fiber or adhesive resin is PVA.
The electrode according to claim 1, wherein is a main component.