HU207611B - Electrode plates, as well as accumulators with use of said plates - Google Patents

Abstract

The electrode plate structure consists of layers of active material either in sheet form or pasted mass form and having pores and/or perforations throughout the active material and having corrugations, ridges, grooves, furrows, creases or other embossments between at least two facing surfaces which are compressed together. - The corrugations, ridges, grooves, furrows, creases provide pathways along which electrolyte may flow in tandem with diffusion through perforations and/or pores of the structure,thereby allowing electrolyte penetration to deep within the structure at a flow rate that allows correct electrochemical reactions by reason of layers or laminations being electrically connected as one body. Sheet material is able to be formed by rolling, pressing, casting, cutting or moulding in tandem or simultaneously. Solid or absorbed electrolyte is compressed between layers.

Description

The present invention relates to an electrode plate for electrochemical power sources, such as lead-acid batteries; the electrode sheet of the present invention comprises a plurality of conductive layers of electrode material, each conductive layer being formed by a surface structure that allows the flow of the electrolyte between adjacent conductive layers and having electrically interconnected conductive layers within an electrode sheet. The surface structure allowing the conductive layers to span and the electrolyte to pass through is provided by irregularities in the surface, such as waves, notches, grooves or protrusions. The conductive layers of the electrode plate may also be lattices filled with porous active material.

The invention also relates to batteries comprising such electrode plates.

The capacity of lead-acid accumulators commonly used in motor vehicles is proportional to the contact surface of the plates with the electrolyte. In a simple lead-acid battery, one electrode can be made of solid lead and the other is made of oxidized solid lead, but such a battery has a very low capacity because the electrode contact surface of the electrodes is relatively small so the electrochemical reaction is small and relatively slow.

The use of paste electrodes has made significant advances in the manufacture of batteries. In this solution, a lead or lead oxide powder is placed in a porous binder. The electrolyte penetrates the porous material and simultaneously contacts a large number of active particles over a relatively large surface. As a result, much greater electrochemical reaction occurs at the electrodes.

In paste plate electrodes, the active material consisting of a porous "active mass" is placed in a lattice structure. The electrolyte diffuses through the mass. The permeability of the electrolyte to the mass is limited by the porosity of the active material.

Advantageously, the electrolyte may only flow at a limited rate in the active mass to optimize the electrochemical reactions in the plate. Through the active mass, respectively. increasing the electrolyte flow around it would have a significant impact on battery performance.

Accordingly, it is an object of the present invention to provide an electrode plate which increases the capacity of the battery.

It is a further object of the present invention to provide an electrode plate which enables the manufacture of such plates to be simplified.

An alternative embodiment of the invention is to provide a paste electrode plate having a higher capacity than conventional paste plates.

It is a further object of the present invention to provide an electrode plate having a large surface area on which capillary capacity and / or increased diffusion allows contact between the active mass and the electrolyte, thereby increasing the capacity of the battery.

According to the invention, the object is solved by an electrode plate having a plurality of conductive layers of electrode material, each conductive layer having a surface structure permitting the flow of electrolyte between adjacent layers, and only layers of equal polarity are located within an electrode plate. which are electrically connected to each other. Preferably, said surface structure comprises surface irregularities on the layers of the sheet. Preferably, said surface structure comprises waves, notches, edges, grooves, creases or protrusions on at least one surface of the electrode sheet layers.

In a preferred embodiment of the invention, perforations or pores are formed in the layers of the electrode material to allow the electrolyte to move through the layers.

In another preferred embodiment, the electrode plate consists of a single continuous electrode material which is folded and pressed together, electrically interconnected. The material of the electrode plate is preferably lead.

The invention also relates to a battery having a vessel, an electrolyte contained therein, and having at least one cell in the electrolyte, the cell comprising a cathode plate and an anode plate, and at least one of the plates being a laminate formed as above.

According to the invention, the electrode plate can also be formed by having a plurality of conductive grids, each grid having a porous active mass, the grids being permeable to the electrolyte and having passageways of the size required for capillary flow of the electrolyte. that are electrically connected.

The invention will now be described in more detail with reference to embodiments and drawings. In the drawings it is

Figure 1 is a perspective view of a folded thin metal electrode plate made in accordance with the present invention;

Figure 2 is a perspective view showing a partial breakout of a laminated frame and paste electrode plate made in accordance with the present invention.

According to the invention, each electrode plate is made of a multilayer electrode material electrically interconnected. There is only a very short distance between the layers, so that capillary or diffusion allows efficient penetration of the fresh electrolyte. contact with the entire surface of the active substance.

In a preferred embodiment, the sheets of the invention increase the flow rate of the electrolyte by utilizing capillary-assisted diffusion, where the capillaryity occurs between the layers of the electrode structure.

Figure 1 illustrates an accordion-like embodiment of a sheet according to the invention, each electrode sheet (10) having a plurality of layers (11) of a suitable composition of thin electrically conductive material. For example, a lead battery1

For use on a sheet of aluminum, the layers (11) may be made of thin lead foil in one sheet and a lead foil with an outer layer of lead oxide (11) in the other sheet. The layers (11) have an approx. 5-20 pm, preferably approx.

10-12 μιη thick.

In a preferred embodiment, the plate (12) of Figure 1 is provided with a perforation. In addition, it is desirable that the layers (13) of the electrode (11) are corrugated or ribbed, grooved, notched, bumpy, notched, creased, etc., allowing the electrolyte to contact the surface of the electrode plate (10). after assembly. The waves (13) and the like may be formed simultaneously or sequentially with the perforation (12). The waves (13) and the like may be straight, circular, wavy, irregularly spaced, or any other arrangement that allows fluid to flow between layers (11) and prevents adjacent layers (11) from being so close to each other the fluid cannot move between them. Instead of the waves (13) and the like, other material may be placed between the layers of the electrode (11) to provide fluid flow. so e.g. once the lead foil has been formed, a material can be extruded onto the surface of the foil to ensure separation of the superimposed layers of the foil.

The plate itself is formed of several layers (11) of electrode material. In the embodiment shown in Figure 1, the layers (11) are folded from a continuous electrode material in an accordion or zigzag fashion. Of course, the layers (11) can also be formed from separate sheets which are electrically connected [e.g. with conductors penetrating one or more of their edges or layers (11)]. Figure 1 shows the bellows folded sheet structure in loose state before compression. In the final step of the manufacturing process, the layers (11) are compressed into a sheet.

A car battery, for example. usually has six cells, each of which has approx. comprising eleven separate positive and negative plates, each of which is composed of ten to fourteen (11) layers having a material thickness of about 10 mm. 5-20 pm.

The electrode plates (10) are provided with a connecting element for forming the cell, e.g. with the electrical outlet (14) shown in Figure 1. In this embodiment, each plate layer is rectangular and has an electrical outlet on one side (14).

It will be appreciated that after forming and pressing, the electrolyte may flow between the layers of the sheet due to waves or similar shapes. The drawing shows only one electrode, which can be either an anode or cathode, depending on the material of which the electrode plate (10) is made and in which electrochemical cell it is placed. Again, it is emphasized that each sheet layer is electrically bonded, thus forming a single sheet and chemically reacting as a single electrode when pressed into the electrolyte.

The folded embodiment of the electrode plate (10) can be made in a roller or die press and can be cut into a finished plate in one or two steps without the need for other materials (as in the prior art). No reinforcing materials are needed as the plywood forms a rigid structure. Casting is also possible.

Another embodiment of the electrode plate (10) is shown in FIG. In this embodiment, the lattice (15) is filled with paste (16) on both sides. The active substance (16) may be a conventional electrode mass. For example, in the manufacture of a lead battery, the active ingredient (16) is a porous mass containing a binder and a lead or lead oxide powder. The grid (15) is preferably made of lead or an oxidized surface and is thinner than conventional grids. so. for example, each grid (15) has a thickness of approx. It is between 45 and 145 pm, preferably between 75 and 100 pm, when used with a lead battery. Each of the battery electrode plates (10) consists of a plurality of lattices filled with mass. The number of grids is essentially unlimited, with more gratings per plate with more capacity, less grids per plate, but more plates per cell with more current. For example, a car battery can have 2 to 10 grids per plate, depending on the battery type. Of course, the layers of each disc are electrically bonded and there are no layers of opposite polarity between them.

Preferably, the electrical connection may be provided in the circumference of the grids (15) between the plates. During operation of the plate, diffusion occurs through the pores of the active material (16), which is also facilitated by capillarity from the proximity of the mass-filled grids (15) in the plate. A reinforcing mesh (17) may also be arranged between the grids (15) in the plate. The reinforcing mesh (17) is preferably made of fiberglass or other inert material.

It can be seen from the figures that liquid or gas can flow between the layers of active material of the electrode plates (16) of the present invention. According to the invention, solid electrolyte can also be used between the layers.

In the plate of Fig. 1, the electrolyte flows through the perforation (12) and through the capillarity between the layers (11), while in Fig. 2, the electrolyte flows through the pores of the active material (16) and also between the layers of each plate. with the help of capillarity. The described structure enhances the electrolyte exchange and increases the capacity of the battery. Compared to a conventional lead-acid battery having paste plates, the battery-weight ratio of the battery provided with the plates according to the invention but otherwise constructed in the same way is much better. The battery can also discharge quickly.

Although the invention has been described in terms of preferred embodiments, many other embodiments are possible within the scope of the invention.

Claims (9)

PATENT CLAIMS An electrode plate for an electrochemical power source, characterized in that it comprises a plurality of conductive layers (11) made of electrode material, each conductive layer 611 Β (11) is formed by a surface structure permitting the flow of the electrolyte between adjacent conductive layers (11) and having conductive layers (11) electrically connected to one another within an electrode plate (10). Electrode plate according to claim 1, characterized in that the layers (11) of the plate (10) are formed with surface irregularities. An electrode plate according to claim 1, characterized in that at least one surface of the layers (11) of the electrode plate (10) has waves (13), notches, grooves, creases or protrusions. 4. An electrode plate according to any one of claims 1 to 3, characterized in that perforations (12) or pores are provided in the layers (11) of the electrode material for the movement of the electrolyte through the layers (11). 5. An electrode plate according to any one of claims 1 to 3, characterized in that the electrode plate (10) consists of electrically bonded layers (11) formed and folded from a single continuous electrode material. 6. Electrode plate according to any one of claims 1 to 3, characterized in that the conductive layers (11) are made of lead. A battery having a vessel, an electrolyte contained therein and at least one cell in the electrolyte, the cell comprising a cathode plate and an anode plate, characterized in that at least one of the plates comprises a plurality of conductive layers (11) made of electrode material, each 11) is formed by a surface structure allowing an electrolyte flow distance between adjacent layers (11), and layers (11) of the same polarity are electrically bonded to one another within an electrode plate (10). An electrode plate, characterized in that it comprises a plurality of conductive grids (15), each of which comprises a porous active mass (16), the gratings (15) being permeable to the electrolyte, and passing the electrolyte between the grids (15) passages are formed and each plate (10) has electrically interconnected grids (15) of the same polarity. A battery comprising at least two electrode plates (10) of opposite polarity that are in contact with an electrolyte, characterized in that at least one of the electrode plates (10) comprises grids (15) filled with porous active material (16). They are permeable to the electrolyte and include passageways for the electrolyte to pass through, and each electrode plate (10) has electrically interconnected grids (15).