JPS6355865A - Closed type lead battery and process for production thereof - Google Patents

Abstract

PURPOSE:To improve the efficiency of output per weight and volume by providing a reinforced protrusion structure higher than a plate on the internal bottom in a plate housing compartment and providing a counter part reinforced protrusion structure in another plate housing compartment whereby both plate housing compartments are integrally molded intervening a hinge part between them. CONSTITUTION:In a positive plate compartment, integrally molded protrusion structures 4, 5 are located in a space of grids and at least one of them is higher than the plate thickness. Accordingly, when an active substance is filled in grids, at least one of the protrusion structures 4, 5 is exposed. A negative plate compartment has actually the same structure as the positive plate compartment including that counter part protrusion structures are located in the positions corresponding to those of protrusion 4, 5. These positive and negative plate compartments are integrally molded intervening a hinge part 17. With the arrangement, the depth of both plate compartments can be extremely minimized in comparision with the area size thereof and the efficiency of output per weight and volume can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a sealed lead-acid battery used as a portable power source for portable cassette recorders, portable video recorders, etc., and particularly relates to a sealed lead-acid battery that is small, thin, and lightweight. It is related to storage batteries.

Conventional technology and its problems In order to make sealed lead-acid batteries smaller, thinner, and lighter, conventionally, for example, the power generation elements, such as a positive electrode plate, a negative electrode plate, and a separator, were stacked together and packaged in a synthetic resin film bag. be. However, when charging and discharging, especially when charging, the battery case (bag)
swells, so the clamping force between the power generating elements is lost. To prevent this, it is necessary to store it in a rigid box (protective container) made of another metal, etc., and the overall thickness is about 5 fins. Therefore, even though the power generating element is wrapped in a thin film, the output efficiency (per weight and per volume) obtained is not very good.

On the other hand, we made a storage chamber for the electrode plates out of synthetic resin.
A sealed lead-acid battery has also been proposed in which a positive electrode chamber or a negative electrode chamber containing a positive electrode plate or a negative electrode plate is provided, and these are stacked and bonded via a separator. However, since this method uses synthetic resin for the battery case, it was necessary to increase the wall thickness in the large area of the storage chamber to prevent the battery case from swelling when the internal pressure rises. . For this reason, the thickness of the battery as a whole is 6 tones, and the output efficiency (
There was a drawback that it was not possible to increase the weight (per weight and per volume).

As described above, conventional sealed lead-acid batteries are not necessarily satisfactory as portable power sources that require the highest output efficiency per weight and volume. The purpose of the present invention is to provide a small, thin, and lightweight sealed lead-acid battery with excellent output efficiency.

Structure of the Invention In order to achieve the above-mentioned object, the present invention provides a sealed lead-acid structure in which a positive electrode chamber storing a positive electrode plate and a negative electrode chamber storing a negative electrode plate are overlapped and joined via a separator. The storage battery is a sealed lead-acid battery in which at least one of the electrode plate storage chambers is extremely shallow in depth compared to the width and length of the inner compartment. At the inner bottom of the electrode plate storage chamber, at least one
The other electrode plate storage chamber has reinforcing protrusions at corresponding positions, and both electrode plate storage chambers are molded together via a hinge section, which is then bent and joined. The inner bottoms of the electrode plate storage chamber are integrated with each other by joining the protrusions. ' At least one of the reinforcing protrusions penetrates the separator and is joined to each other.

Further, one of the reinforcing protrusions is an upper planar protrusion with a flat upper surface, and the corresponding protrusion is a needle-like protrusion.

In this case, the height of the needle-like projection is higher than at least the depth of the electrode plate storage chamber.

Both positive and negative terminals are integrally insert-molded in the electrode plate storage chamber.

An exhaust port and a safety valve are arranged on either side of the electrode plate storage chamber.

A positive electrode storage chamber for storing a positive electrode plate and a negative electrode storage chamber for storing a negative electrode plate are integrally formed via a hinge part, and the storage chamber has reinforcing protrusions at corresponding positions. This method of manufacturing a sealed lead-acid battery is characterized in that after the plate is stored, the plate is bent at the hinge portion via a separator, and then the outer edge of the storage chamber and the reinforcing protrusion are joined to each other by ultrasonic welding.

Example An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view showing an example of the internal structure of a sealed lead-acid battery according to the present invention, and FIG. 2 is a perspective view showing an example of the structure of a positive electrode plate storage chamber used in the sealed lead-acid battery of the present invention. FIG. 6 is a diagram showing another embodiment of the electrode plate storage chamber of the present invention.

1 is a positive electrode storage chamber, 2 is a positive electrode grid, 3 is a positive electrode terminal, 4 is a top projection, 5 is a needle-shaped projection, 6 is an exhaust port, 7 is a partition wall, 8 is a positive electrode active material, 9 is a joint, 10 is a An exhaust valve, 11 is an insert, 12 is a separator, 15 is a negative electrode grid, 14 is a negative electrode terminal, 15 is a negative electrode active material, 16 is a negative electrode storage chamber, and 17 is a hinge portion.

A positive electrode plate chamber containing a positive electrode grid and a positive terminal is used in the positive electrode storage chamber as shown in FIG. In this positive electrode chamber, projections 4 and 5 are integrally molded in the portion located in the aerial part of the lattice. The height of at least one of the protrusions 425 is higher than the thickness of the electrode plate. Therefore, when the grid is filled with active material, at least one of the protrusions 4.5 is exposed.

Although the negative electrode chamber is not shown, it is located at a position corresponding to the protrusion 4y5.
The structure is substantially the same as the positive electrode chamber, including having a mating protrusion.

Either one of the positive and negative electrode chambers has an exhaust port leading to an exhaust valve.

FIG. 1 is a cross-sectional view of a sealed lead-acid battery in which positive and negative electrode chambers are overlapped with each other via a separator and then bonded together. The positive electrode chamber is integrally formed with a needle-like protrusion, an upper flat protrusion, an exhaust port, and a partition wall that prevents the active material from extruding when filled.
A positive electrode grid is arranged on this and filled with a positive electrode active material. Like the positive electrode chamber, the negative electrode chamber also has a needle-like projection, an upper planar projection, and a ward [6! are integrally molded, a negative electrode grid is arranged, and a negative electrode active material is filled. The height of the needle-like protrusion in both the positive and negative electrode chambers is higher than not only the thickness of the electrode plate but also the depth of the storage chamber, and has enough height to reach the upper plane protrusion of the corresponding mating electrode chamber. The planar protrusion has a height approximately equal to the thickness of the electrode plate. The terminals are insert molded. A storage chamber in which a positive electrode chamber and a negative electrode chamber are integrally formed via a hinge part is used. It is as shown in Fig. 5, and the positive and negative polarity chambers are shown in Fig. 1 and 2.
It has reinforcing protrusions as shown in the figure. Furthermore, a positive electrode terminal and a negative electrode terminal are integrally inserted into the storage chamber during molding. This is more preferable because it is sufficient to simply weld the grid to the terminals during post-processing. Further, although an exhaust port and an exhaust valve (not shown) are provided on the outside, this is a good idea because the actual thickness of the battery can be reduced.

Since the positive and negative polarity chambers are integrally molded via the hinge portion, the reinforcing projections can be accurately joined by simply bending the polarity chambers and overlapping them, without causing the reinforcing projections to shift when joining the polarity chambers. Therefore, the airtightness and liquidtightness of the battery are improved, and the durability against engraving and productivity are also improved.

Since the hinge part is unnecessary after the positive and negative polarity chambers are joined, it may be removed if necessary.

The positive and negative electrode chambers obtained in this manner are placed one on top of the other with a separator interposed therebetween, and are joined together by ultrasonic welding. At this time, the needle-like protrusions penetrate the separator and reach the corresponding upper flat protrusions, and the protrusions are joined to each other at that portion. 9 is the joint part.

In this case, the separator must be easily penetrated and must not cause excessive tearing. It was confirmed that the separator, which is used in sealed lead-acid batteries and is made into a sheet mainly made of glass fiber with a diameter of 1 μm or less, has these necessary characteristics and does not cause short circuits at the penetrating portions.

Furthermore, if a synthetic fiber such as polypropylene, polyester, synthetic pulp, acrylonitrile, etc. alone or mixed with glass fiber is used as a separator instead of glass fiber, the separator will also form at the joint between the needle-like protrusion and the upper plane protrusion. Since they are bonded at the same time, the possibility of short circuits occurring can be further reduced.

The electrolytic solution may be injected into the battery by impregnating the active material or separator before joining the positive and negative electrode chambers, or by injecting the electrolyte through the exhaust port after joining.

Next, an exhaust valve and a valve holder are attached, and the sealed lead-acid battery of the present invention is obtained (through a chemical formation process if necessary).

With the above configuration, according to the present invention, the depth of the positive φ and negative electrode chambers becomes the thickness of the completed battery compared to the width of the chambers. ), it is possible to obtain a flat sealed lead-acid battery with an extremely thin thickness.

In conventional batteries, when the area of the storage chamber increases, the storage chamber swells as the internal pressure of the battery increases. 1.0
However, since the battery according to the present invention has reinforcing protrusions, the bulge in the storage chamber can be significantly reduced. As a result, the bottom wall thickness of the storage chamber was reduced to 0.
．． It can be made as thin as 1 to 1.0 path.

Therefore, the total thickness of a flat, small, sealed lead-acid battery, which conventionally had a thickness of about 6 mm, can be reduced to about 2.6 to 4.5 mm. Due to this reduction in thickness, the structural efficiency of the sealed lead-acid battery is 55 to 100 Wh/l according to the present invention, compared to 40 to 50 Wh/l for conventional flat single-sized batteries.
It can be improved up to /1.

Regarding the spacing and number of reinforcing protrusions, the thickness of the bottom wall of the storage chamber,
This may vary depending on the storage chamber molding material, the set opening pressure of the exhaust valve, the allowable bulge, etc., so these must be taken into account when designing appropriately.

Regarding the shape of the reinforcing projections, in the above embodiment, each storage chamber is provided with a needle-shaped projection and an upper planar projection, but the present invention is not limited to this. may have only a needle-like protrusion, and one storage chamber may have only an upper flat protrusion.

In this case, the active material filling operation is easy and preferred. Furthermore, in this case, the height of the upper planar projection does not necessarily need to be higher than the thickness of the electrode plate, and it is sufficient that the height is such that the bottom surface of the storage chamber is not torn by the needle-shaped projection during joining. If the height of the upper flat projection is lower than the electrode plate thickness, the height of the opposing needle-like projection must be such that it reaches the upper flat projection during joining and still has a welding allowance. The bonding between the layers is better when the active material is uncured, since this makes it easier for the protrusions to penetrate. In this case, the active material is hardened after bonding. The molding material for the storage chamber is ABS t A'Sy, which is used for the containers and lids of regular sealed lead-acid batteries.
Materials such as reinforced As can be used. However, without being limited thereto, thermoplastic synthetic resins such as PPtPE can also be used.

From the viewpoint of making the inner bottom wall of the storage chamber as thin as possible, materials with high rigidity are preferable, and materials whose strength (rigidity) is improved by adding and modifying the above-mentioned materials with various fillers can also be used.

The most suitable material is a liquid crystal polymer (for example, sold by Volipstick Co., Ltd. under the trade name 1 Pectra'').

This material not only has high rigidity, but also has low viscosity when melted, and has excellent fluidity, making it easy to mold even extremely thin parts of 0.1 mm, making it possible to mold the bottom of the storage chamber to an extremely thin thickness. be.

Ultrasonic welding is highly productive for joining storage chambers together.

It is preferable that the partition wall that partitions the part to be filled with the active material be provided around the four circumferences of the inner wall of the storage chamber, since this improves workability. Note that the height must be lower than the depth of the storage chamber since there is a risk of breaking the separator when joining the storage chambers. This partition wall forms a void around the outer periphery of the partition wall. Since excess electrolyte can be retained in this gap, it is suitable for manufacturing a battery through a chemical formation process after joining the storage chambers.

An embodiment of a sealed lead-acid battery according to the present invention is as follows.

55111L x 55mm is installed in a storage chamber made of reinforced As with an inner bottom thickness of 0.3mm and reinforcing protrusions spaced at approximately 10mm intervals, and external dimensions of 66L x 70FFL and WXL5T (welding fee included).
A positive electrode chamber and a negative electrode chamber were created by storing a W x O, 8 mmT electrode plate. Both chambers were overlapped with O and BmtnT glass fiber separators interposed therebetween and joined by ultrasonic welding.

Approximately 4.5 cc of an electrolytic solution with a specific gravity of 1.60 was injected, and an exhaust valve with an opening pressure of 0.05 atm was attached to obtain a sealed lead-acid battery. The external dimensions of this battery are 65fMtW x 70LX3.
The weight of the gas sT1 was approximately 44 g.

The battery capacity was 525 mAh at a 20-hour rate, and the overcharge characteristics did not swell by more than 0.1 dragon even after continuous overcharging of 507 FfA. Charge/discharge cycle characteristics are 30
It had a lifespan of 0 or more times. The volumetric efficiency of this battery is 79
Wh/, +, weight efficiency is 26Wh/kLj,
In particular, the volumetric efficiency is extremely superior compared to the conventional 40-50Wh/ha15-25WhA9.

Moreover, since there is no risk of blistering, there is no need for a separate protective container like in conventional film packaging.

Effects of the Invention As mentioned above, according to the present invention, it is possible to provide a small, thin, and lightweight sealed lead-acid battery with excellent output efficiency per weight and volume, so its industrial value is extremely large. be.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of a sealed storage battery according to the present invention, and FIG. 2 is a perspective view showing an embodiment of a storage chamber used in the present invention. 1...Positive electrode chamber 4...Top projection 5...Acicular projection 12...Separate lake 9...Joint part
16... Negative electrode chamber 17... Hinge part

Claims (8)

[Claims] (1) In a sealed lead-acid battery in which a positive electrode chamber containing a positive electrode plate and a negative electrode chamber containing a negative electrode plate are stacked and bonded via a separator, at least one of the electrode plate storage chambers is , whose depth is extremely shallow compared to the width and length of the inner nozzle, and has at least one reinforcing protrusion located in the gap of the electrode plate current collector on the inner bottom and which is higher than the electrode plate height; The electrode plate storage chambers have reinforcing protrusions at corresponding positions, and both electrode plate storage chambers are integrally molded via a hinge part, which is bent and joined, and the electrode plate storage chamber is formed by joining between the protrusions. A sealed lead-acid battery characterized by having the inner and bottom parts of the battery integrated with each other. (2) The sealed lead-acid battery according to claim 1, wherein at least one of the reinforcing projections penetrates the separator and is joined to each other. (3) The sealed lead-acid battery according to claim 2, wherein the reinforcing protrusion is an upper flat protrusion having one flat upper surface, and the corresponding reinforcing protrusion is a needle-like needle-like protrusion. (4) The sealed lead-acid battery according to claim 5, wherein the height of the needle-like protrusion is higher than at least the depth of the electrode plate storage chamber. (5) The sealed lead-acid battery according to claim 1, wherein both positive and negative terminals are integrally insert-molded in the electrode plate storage chambers. (6) The sealed lead-acid battery according to claims 1 and 5, wherein an exhaust port and a safety valve are arranged in either one of the electrode plate storage chambers. (7) The positive electrode storage chamber that stores the positive electrode plate and the negative electrode storage chamber that stores the negative electrode plate are integrally formed via a hinge part, and the storage chamber has reinforcing protrusions at corresponding positions, and the storage chamber has reinforcing projections at corresponding positions. A method for manufacturing a sealed lead-acid battery, which comprises storing an electrode plate in a chamber, bending the electrode plate at a hinge portion via a separator, and then joining the outer periphery of the storage chamber and reinforcing protrusions to each other by ultrasonic welding. (8) The method for manufacturing a sealed lead-acid battery according to claim 7, wherein the hinge portion is removed after the storage chambers are joined.