JP3099527B2 - Manufacturing method of sealed lead-acid battery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a sealed lead-acid battery, and more particularly to a method of manufacturing a sealed lead-acid battery holding a large amount of electrolyte.

[0002]

2. Description of the Related Art In many cases, sealed lead-acid batteries are designed to use a positive electrode active material and a negative electrode active material in a considerably larger amount than the theoretical amount, and the capacity of most batteries is determined by the amount of sulfuric acid. Also,
If the battery is repeatedly charged and discharged during use, a so-called stratification phenomenon occurs, which causes a difference in the concentration of sulfuric acid in the battery.In a battery that is used for a long time, moisture permeates from the resin in the battery case, etc. There is a demand for an electrolyte holding material that secures as much electrolyte solution as possible in a battery and has a large surface area in view of the resulting capacity reduction. As a method for securing the electrolyte and preventing stratification, a method of filling a space in the battery with a gel material has been adopted.

As one method, a formed positive electrode plate and a formed negative electrode plate are assembled via a glass fiber separator, and a current collector is welded to a strap for each of a positive electrode and a negative electrode to be integrated to form an electrode plate group. And filling the granular silica powder between the battery case and the electrode plate, bonding the cells adjacent to each other and bonding the lid to the battery case, and assembling the battery. The way to do it is taken.

However, in this method, since the electrode plate is covered with the granular silica powder, absorption of the electrolytic solution into the electrode plate group is slow, it takes time, and dilute sulfuric acid is impregnated so that the silicic acid powder becomes uniform. It is difficult to do so, and the silicic acid powder may remain in the shape of a cage, and the electrolyte may become uneven due to the large amount of electrolyte contained in the electrode plate group. There were drawbacks such as difficulty.

[0005]

Therefore, instead of the method of filling granular silica powder in a battery, a sol solution in which silica powder is uniformly dispersed in dilute sulfuric acid is prepared in advance, and the battery is assembled with the sol solution. To form a battery.

However, when the silica powder solution has a high silica powder concentration, it is difficult to fill the solution into the battery, and the solution can be fluidized by stirring or the like. However, when the silica powder solution exceeds a certain limit, the gel concentration that can be handled is limited.

[0007] In addition, when the battery formation is performed, there is an inconvenience that the concentration of the lower part increases as the liquid decreases due to the formation, and the capacity varies.

[0008]

SUMMARY OF THE INVENTION The present invention is directed to a so-called dry state in which the liquid state in an electrode group is reduced to a shortage less than an appropriate amount, and a sol solution is filled to remove sulfuric acid water in the sol. Side to de-fluidize the sol and provide a position-free battery.

That is, in the method for manufacturing a sealed lead-acid battery of the present invention, a dilute sulfuric acid electrolyte solution, which is less than an appropriate amount, is injected into a battery assembled from a group of electrodes using a retainer type separator. After the electrolyte was in a shortage state, dilute sulfuric acid sol containing sodium silicate or silica powder was filled between the battery case and the electrode group in the battery, and the sulfuric acid solution in the sol was absorbed by the electrode group side. , Making the sol non-fluidized.

Further, the method for producing a sealed lead-acid battery according to the present invention in the case of carrying out battery case formation requires that a battery assembled with an electrode group using a retainer type separator has an excess of an appropriate amount impregnated into the electrode group. The electrolyte solution in the electrode group was reduced by injecting a diluted sulfuric acid electrolyte solution of the electrode plate, and the electrode group in the electrode group was reduced, and the electrode group was brought into an insufficient state of the electrolyte solution, and then diluted with sodium silicate or silica powder. It is characterized in that a sulfuric acid sol is filled between a battery case and an electrode group in a battery, and a sulfuric acid solution in the sol is absorbed on the electrode group side to make the sol non-fluidized.

In any of the above cases, the diluted sulfuric acid sol should be made such that the diluted sulfuric acid sol having a silica powder concentration of 30 to 60 g / l is absorbed by the electrode plate group so that the concentration of the silica powder in the sol is 100 g / l or more. preferable.

In the case of battery case formation, the specific gravity is 1.15 to 15.
A 1.25 diluted sulfuric acid electrolyte was injected, and the specific gravity was 1.25.
It is preferable that the battery case is formed and overcharged to reduce the electrolyte solution to 1.35.

It is preferable that the sulfuric acid concentration is made uniform by filling a sulfuric acid sol having a higher concentration than the average concentration of the electrolytic solution in the battery after the formation of the battery container.

[0014]

According to the present invention, the sol is filled in a battery in a fluidized state, and the concentration of the sol is increased by causing a so-called dry electrode group to absorb the sulfuric acid aqueous solution in the sol, thereby making the sol non-fluidized. Things.

[0015]

The present invention will be described below in detail with reference to examples.

FIG. 1 shows an example of the configuration of a sealed lead-acid battery to which the present invention is applied. In the figure, 1 indicates a battery case made of ABS resin,
The battery case 1 is filled with an electrode plate group 5 composed of a positive electrode plate 2, a negative electrode plate 3, and a glass fiber separator 4 filled with an unactivated material, and a lid 6 is bonded and fixed to the battery case 1. Is assembled. In the figure, 7 indicates a current collector, and 8 indicates a liquid injection hole.

The battery injection hole 8 of the battery thus assembled.
Then, an excessive amount of dilute sulfuric acid electrolyte is injected into the electrode group 5 in excess of an appropriate amount to be impregnated, and then energized to form the positive and negative electrode plates 2 and 3 so that the positive and negative electrode active materials have a theoretical capacity or more. By overcharging, excess hydrogen gas and oxygen gas are electrolyzed and released out of the battery, and the liquid is further reduced by overcharging from an appropriate amount impregnated in the electrode plate group 5.

Thereafter, a flowing sol obtained by dispersing dry silica fine powder (commonly known as Aerosil) in a dilute sulfuric acid electrolytic solution with a stirrer is injected into the space between the battery case 1 and the electrode group 5 and up to the upper part of the electrode group 5. 8, and a part of the diluted sulfuric acid electrolyte solution is sucked from the sol to the electrode group 5 and moved so that the amount of the electrolyte solution in the electrode plates 2 and 3 becomes an appropriate amount. The fluidized sol 9 was obtained.

Next, a more specific example will be described together with a comparative example, taking a 15 Ah battery as an example. Example 1 An electrolytic solution having a specific gravity of 1.25 was subjected to 8 cc / A per battery capacity Ah.
h, and the battery was formed at 250% of the theoretical formation electricity amount.
Further, the battery was overcharged at 100% of the theoretical capacity to obtain a sulfuric acid specific gravity of 1.
30, a sol solution having a silica fine powder concentration of 60 g / liter was filled between the battery case and the electrode plate in an amount corresponding to 2 cc / Ah to produce a prototype battery. When the silica fine powder sol exceeded 90 g / liter, it rapidly non-fluidized and became a gel-like hard cake. Example 2 Next, an electrolyte having a specific gravity of 1.25 was applied at a rate of 8 c per battery capacity Ah.
c / Ah, and the cell was formed at 250% of the theoretical formation electricity amount, and the average specific gravity of the upper and lower electrolytes in the battery was 1.30.
Further, the battery was overcharged at 100% of the theoretical capacity to obtain a sulfuric acid specific gravity of 1.
32, a sol solution having a silica fine powder concentration of 60 g / liter
A battery equivalent to cc / Ah was filled between the battery case and the electrode plate group to produce a prototype. Comparative Example As a comparative example, a conventional battery in which an electrolytic solution having a specific gravity of 1.25 was injected at a rate of 8 cc / Ah per battery capacity Ah and a battery case was formed at 250% of the theoretical formation electricity amount was prototyped.

The initial capacity and the trickle life of the batteries experimentally produced in the above Examples and Comparative Examples were measured, and the results are shown in Table 1 below.

[0021]

[Table 1]

As is clear from Table 1, compared with the comparative example,
In the case of Examples 1 and 2, both the initial capacity and the trickle life were improved, and particularly in the case of Example 2, the life of the trickle was remarkably improved to 6 years.

In the above embodiment, only the case of battery case formation is shown, but it goes without saying that the method of manufacturing a sealed lead-acid battery of the present invention can also be applied to the case where a previously formed electrode plate is used.

[0024]

As is apparent from the above description, according to the method for producing a sealed lead-acid battery of the present invention, a large amount of electrolyte can be ensured, and the difference between the upper and lower concentrations caused by battery formation can be reduced by the sulfuric acid concentration. This can be alleviated by filling the battery with a dense sol.

Further, the surface area is increased by the silica powder, stratification occurring during charging and discharging due to surface tension can be prevented, and the quality of the product can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a sealed lead-acid battery according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Battery case 2 Positive electrode plate 3 Negative electrode plate 4 Separator 5 Electrode plate group 6 Lid 7 Current collector 8 Injection hole 9 Non-fluidized sol

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masaharu Fukawa 1006 Kazuma Kadoma, Kadoma City, Osaka Inside Matsushita Electric Industrial Co., Ltd. (56) References JP-A-63-221565 (JP, A) JP-A-3-3 145067 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H01M 10/10-10/12

Claims (5)

(57) [Claims] An insufficiency of a dilute sulfuric acid electrolytic solution is injected into a battery assembled with an electrode group using a retainer type separator, and the electrode group is brought into a state of insufficient electrolyte. Alternatively, a dilute sulfuric acid sol containing silica powder is filled between the battery case and the electrode group in the battery, and the sulfuric acid solution in the sol is absorbed to the electrode group side, thereby making the sol non-fluidized. Manufacturing method for sealed lead-acid batteries. 2. A battery assembled with an electrode group using a retainer-type separator is poured with a dilute sulfuric acid electrolyte in excess of an appropriate amount for impregnating the electrode group. The electrode group is brought into a state of lack of electrolyte solution, and then dilute sulfuric acid sol containing sodium silicate or silica powder is filled between the battery case and the electrode group in the battery. A method for producing a sealed lead-acid battery, characterized in that the sol is made non-fluid by absorbing the sulfuric acid solution into the electrode plate group side. 3. The method according to claim 1, wherein a diluted sulfuric acid sol having a silica powder concentration of 30 to 60 g / l is absorbed by the electrode group so that the silica powder concentration in the sol is 100 g / l or more. A method for producing a sealed lead-acid battery as described in the above. 4. A dilute sulfuric acid electrolytic solution having a specific gravity of 1.15 to 1.25 is injected, and a battery case is formed until the specific gravity becomes 1.25 to 1.35 to perform overcharging to reduce the electrolytic solution. 4. The method for producing a sealed lead-acid battery according to claim 2, wherein the battery is liquid. 5. The method according to claim 2, wherein the sulfuric acid concentration is made uniform by filling a sulfuric acid sol having a higher concentration than the average concentration of the electrolytic solution in the battery after the battery case formation is completed. For manufacturing sealed lead-acid batteries.