JPH0530300Y2 - - Google Patents

Description

[Detailed Description of the Invention] A. Field of Industrial Application The present invention relates to an electrolyte circulation type stacked battery that makes it possible to downsize the battery device and ensure improved voltage efficiency.

B. Summary of the invention This invention was arrived at as a result of studying the frame materials of framed electrodes and framed membranes used in electrolyte circulation type stacked batteries, and aims to improve voltage efficiency and make the battery more compact. In order to improve the volumetric energy density, electrolysis using a framed electrode and a framed membrane in which an electrolyte flow path is formed on one side of the frame of the electrolyte circulation type stacked battery is used. This invention relates to a liquid circulation type stacked battery.

C. Prior Art The basic structure of a zinc-bromine battery is, as shown in FIG. 2, a laminated end plate 2 between two clamping end plates 1,
Electrode end plate 3, packing 4, frame membrane with microchannel 5, intermediate electrode with flat plate frame 6, manifold (positive electrode) 7, manifold (negative electrode) 8, microchannel forming part 9, separator (membrane) 10,
A spacer mesh 11, an electrode 12, and a current collector mesh 13 are placed, and bolts are passed through bolt holes 14 and tightened and fixed.

In the structure of the framed membrane used in such situations, as shown in JP-A-60-65481, a positive electrode and a negative electrode are arranged on both sides, so as shown in FIG. Frame 1 of separator 10
Forming grooves 15 for forming channels and microchannels on both sides of 8, respectively,
These channels and microchannels function to uniformly distribute the electrolyte from the manifold to the surfaces of the positive and negative electrodes.

D Problems to be Solved by the Invention However, since it is necessary to form grooves 15 on both sides of the frame 18 of the separator 10 to secure channels and microchannels, it is difficult to maintain the mechanical strength of the frame 18 itself. In order to do this, it is necessary to have a certain degree of thickness.

Specifically, for example, in FIG. 3, if grooves with a depth of 1 mm are to be provided on both sides of the frame 18 of the separator 10, the thickness of the frame 18 itself will be approximately 3 mm.
A thickness of about mm is required.

Naturally, this increases the distance between the negative and positive electrodes, which not only causes the battery to become larger, but also causes a decrease in voltage efficiency due to the increased distance between the electrodes. There was a problem.

In particular, in order to increase the output of batteries, the current trend is to increase the current and increase the voltage, which increases the electrode area, increases the number of stacked single cells, and increases the weight of the components. A solution to this problem has been an important issue.

E. Means for Solving the Problems In order to solve the problems in the conventional technology, various studies were conducted, and in the electrolyte circulation type stacked battery, the frame part of the framed electrode and framed membrane used here was improved. They have achieved an electrolyte circulation type stacked battery characterized by the use of an electrolyte flow path formed on one surface.

That is, conventionally, the (separator 10
) Digged grooves 15 for forming channels and microchannels on both sides of the frame 18, respectively.
However, this style has been discontinued, and the frames 1 of each of the intermediate electrode 6 with a flat plate frame and the membrane 5 with a frame 5 have been changed.
By ensuring a flow path for the electrolytic solution only on one side of the membranes 8 and 19, the thickness of the frame 18 of the framed membrane 5 is reduced, and as a result, the thickness of the entire stacked battery is reduced.

Note that the frame 19 has conventionally been necessary for electrically insulating and supporting the conductive electrode 12 and for forming a manifold.

F Effect Forming an electrolyte flow path on one surface of the frame 19 of the framed electrode and the frame 18 of the framed membrane according to the present invention will be specifically explained with reference to FIG. 1.

FIG. 1 shows a longitudinal cross-sectional view of the main parts of the separator 10 and the electrode 12, in which grooves 15 for channels 16 and microchannels 17 are formed on one side in the same direction, respectively.

By dividing the electrolyte flow path between the membrane and electrode frames 18 and 19 in this way, the flow paths are not formed on the front and back surfaces of a single member, so that the flow paths do not cross each other. By eliminating overlap, the thickness of the frame is reduced, which not only facilitates the processing of the framed member, but also improves processing accuracy and makes it possible to perfect the seal between the members.

The depth of the groove 15 may be approximately 1 mm, which means that the thickness of the frame member may be approximately 2 mm.

The distance at which the frame members 18 and 19 engage the electrode 12 or the separator 10 is preferably 0.5 mm or more, and the thickness of the engagement is preferably 0.5 mm or more.

Note that since the separator is soft, better results can be expected if the biting thickness is made slightly thinner.

Generally, any material can be used for the frame members 18 and 19 as long as it exhibits corrosion resistance against the electrolyte, but plastic, particularly polyolefin plastic, is most commonly used.

Moreover, in this invention, the electrode 12 and the separator 1
A packing 4 is used between the two electrodes, but any packing 4 can be used as long as it is stable against the electrolyte and electrically insulating.

The thickness of this packing 4 is approximately 0.5 mm.

G. Examples Next, the structure and effects of the present invention will be explained while showing comparative examples and examples of several combinations of framed electrodes and framed membranes.

Comparative Example A battery member having the configuration shown in FIG. 3 was formed.

The thickness of the separator 10 in this case is 1.2 mm according to the conventional manufacturing method, and the thickness of the frame material 18 that engages this separator is 3 mm, and the length of the engaged part is 0.5 mm. The depth of the grooves formed on both sides of the frame material was 1.1 mm at the concave part and 0.9 mm at the flat part at the boundary between the separator and the frame, and the depth of the grooves formed on both sides of the frame material was 1.0 mm.

For the separator frame material formed in this way
An electrode frame material 19 was laminated with a packing material 4 having a thickness of 0.5 mm interposed therebetween.

Note that the frame material for the electrode 10 with a thickness of 1.3 mm is as follows:
The thickness is 2.3 without any processing such as channels.
mm frame, and the thickness of the part where the electrode is inserted is 0.5 mm.
mm.

The distance between the separator and the electrode in this case is
1.9 mm, and the distance between electrodes was 5.0 mm.

Example 1 A groove 15 with a depth of 1 mm as shown in FIG. A structure was formed which included a framed electrode 6 consisting of a 0.5 mm packing 4 sandwiched between the packing and a framed membrane 5.

Note that, as a matter of course, electrode materials or separator materials extend inside each of these frames.

The edge of the 1.3 mm thick electrode material is inserted into the frame material to a thickness of 0.5 mm, and the 1.2 mm thick separator is inserted into the frame with a recessed part of 0.6 mm and a flat part of 0.4 mm. It is molded to maintain its intended form.

Therefore, the distance between the separator and the electrode in this case is 1.4 mm, and the distance between the electrode is 4.0 mm.
It became mm.

Compared to the conventional model, the distance between the electrodes has been reduced by 1.0 mm per cell, improving voltage efficiency due to voltage drop loss and reducing the volume of the battery body by 20 mm.
%, it was possible to improve the energy density.

Example 2 With the configuration of Example 1, the distance between the electrode and the separator was set to 1.9 mm, which is the same as in the comparative example, and the frame thickness of the separator and electrode was increased to 2.65 mm, respectively, and the minimum thickness of the channel and microchannel part was set to 1.9 mm, the same as in the comparative example.
0.65mm, increased by 0.35mm with electrodes.

At this time, the thickness of the flat part where the separator and frame engage is 0.725 mm, and the thickness of the engagement part between the electrode and frame is:
It is 0.675mm.

This increases the adhesion between the frame and the electrode or separator, and by increasing the minimum frame thickness to 1.65 mm, the moldability (resin flow) of the synthetic resin of the frame material is improved, and the thickness direction An improvement in molding accuracy was observed.

Furthermore, by making the shapes and dimensions of the separator and electrode channels and the frame with microchannels the same, there is an advantage that only one molding die is required.

Example 3 In Example 2, when the groove depth of the channel and microchannel was changed from 1 mm to 1.65 mm,
It has been found that it is possible to significantly reduce the pressure loss of the electrolyte flow, and it is possible to suppress the loss of the electrolyte circulation pump.

H. Effects of the invention According to the apparatus of the present invention, various inconveniences seen in the conventional apparatus have been solved, and the quality of the final molded product has been improved compared to the conventional apparatus.

To be more specific, (1) it is now possible to shorten the distance between the electrodes, making it possible to improve voltage efficiency; (2) it is now possible to shorten the distance between the electrodes. (3) During injection molding operations, resin flows better and molding accuracy can be improved. (4) With the same distance between the separator and electrode as before, it is possible to increase the packing thickness and improve sealing performance. (5) By increasing the groove depth of channels and microchannels, electrolytic It is possible to enjoy effects such as being able to reduce the energy loss of the liquid circulation pump.

[Brief explanation of drawings]

Fig. 1 is a partial cross-sectional view of a frame material having separators and electrodes formed according to the present invention at its ends, Fig. 2 is a partially exploded perspective view showing the basic structure of a laminated zinc-bromine battery, and Fig. 3 is a partially exploded perspective view showing the basic structure of a laminated zinc-bromine battery. FIG. 2 is a partial cross-sectional view of a frame member having a separator and an electrode at its ends, which is constructed using a conventional manufacturing method. 1... Tightening end plate, 2... Laminated end plate, 3... Electrode end plate, 4... Packing, 5... Membrane with frame with microchannel, 6... Intermediate electrode with flat plate frame, 7
... Manifold (positive electrode), 8 ... Manifold (negative electrode), 9 ... Microchannel forming section, 10
... Separator (film), 11 ... Space mesh, 12 ... Electrode, 13 ... Current collection mesh, 14
...Tightening bolt hole, 15...Groove, 16...Channel, 17...Micro channel, 18,1
9...Frame.

Claims (1)

[Claims for Utility Model Registration] A framed electrode with a frame provided around the electrode plate and a framed membrane with a frame provided around the diaphragm are laminated together, and a frame is provided between the electrode surface and the diaphragm surface. An enclosed cathode or anode reaction chamber is formed, and the electrolyte circulation manifold is formed by passing through opposing positions of each of the laminated frames. In an electrolyte circulation type stacked battery configured to allow an electrolyte to flow in and flow out to the other manifold via an outflow passage, the electrolyte may flow into or out of one of the positive electrode or negative electrode reaction chambers. An electrolyte circulation type stacked battery, characterized in that a passage is provided on one side of the frame of the framed electrode, and a passage through which the electrolyte flows into or out of the other reaction chamber is provided on one side of the frame of the framed membrane. .