Electromotive force generating device

Abstract

An electromotive force generating device 10 comprises: a power generation means 14 which has an electrolyte-containing body 11 containing an electrolytic solution, a positive electrode 12, and a negative electrode 13, and which generates an electromotive force when the positive electrode 12 and the negative electrode 13 come into contact with the electrolyte-containing body 11; and a container 16 in which the whole or a part of the electrolyte-containing body 11 is housed in a sealed state together with a liquid. Accordingly, in the electromotive force generating device 10, the humidity in the container 16 is kept at a certain level or higher, and a decrease in output current and output voltage due to a decrease in atmospheric humidity can be suppressed.

Description

Electromotive force generating device 【0001】 The present invention relates to an electromotive force generating device in which a positive electrode and a negative electrode are in contact with an electrolyte solution to generate an electromotive force. 【0002】 A specific example of an electromotive force generating device in which a positive electrode and a negative electrode are in contact with an electrolyte solution to generate an electromotive force is described in Patent Document 1. The electromotive force generating device (rubber battery) includes an electrolyte-containing rubber that holds an electrolyte solution in which a deliquescent substance is dissolved in a flow path formed in a rubber material, and a carrier capable of supporting the deliquescent substance is distributed in the rubber material. Since the electrolyte-containing rubber contains a deliquescent substance, it can take in moisture (water vapor, etc.) from the surrounding atmosphere. Therefore, as long as the electromotive force generating device is not placed in a special environment with a humidity of substantially 0%, the electrolyte-containing rubber maintains the state of holding the electrolyte solution, that is, the state of generating an electromotive force. 【0003】 Japanese Patent No. 7385203 【0004】 Here, the inventors of the present application have experimentally verified that when the humidity of the place where the above electromotive force generating device is installed decreases, the output current and output voltage of the electromotive force generating device decrease. In this regard, if the electromotive force generating device itself is redesigned so that the values such as the output current increase, it is possible to output a current and voltage greater than the required magnitude. However, for various reasons, when the electromotive force generating device cannot be redesigned, it is important to suppress the decrease in the output current and output voltage of the electromotive force generating device due to the decrease in the ambient humidity. These also apply to an electromotive force generating device in which the substance holding the electrolyte solution is other than a rubber material (such as a sponge). 【0005】 The present invention has been made in view of such circumstances, and an object thereof is to provide an electromotive force generating device capable of suppressing a decrease in output current and output voltage due to a decrease in ambient humidity. 【0006】An electromotive force generating device according to the present invention, in line with the above objective, comprises a power generation means having an electrolyte-containing body containing an electrolyte solution, a positive electrode, and a negative electrode, wherein the positive electrode and the negative electrode come into contact with the electrolyte-containing body to generate an electromotive force, and a container containing all or part of the electrolyte-containing body together with the liquid in a sealed state. Here, in the electromotive force generating device, an absorbent member that absorbs the liquid may be placed inside the container. In the electromotive force generating device, the inside of the container may be configured such that a space S1 in which the liquid is placed and a space S2 in which the electrolyte-containing body is placed are separated by a permeable membrane that allows the vaporized gas of the liquid to pass through but does not allow the liquid to pass through. The electromotive force generating device may further be configured to include a heating means for heating the inside of the container. The heating means may be configured to generate heat through an exothermic reaction. The heating means may also be placed inside the container and generate heat when the liquid comes into contact with it. The liquid may come into contact with the heating means when the container is tilted. 【0007】 The electromotive force generator according to the present invention comprises an electrolyte-containing body containing an electrolyte solution, a positive electrode, and a negative electrode, and a power generation means that generates an electromotive force when the positive electrode and the negative electrode come into contact with the electrolyte-containing body, and a container that contains all or part of the electrolyte-containing body together with the liquid in a sealed state. As such, the humidity inside the container can be kept above a certain level, and a decrease in output current and output voltage due to a decrease in ambient humidity at the installation location of the electromotive force generator (i.e., humidity outside the container of the electromotive force generator) can be suppressed. 【0008】 This is an explanatory diagram of an electromotive force generating device according to one embodiment of the present invention. This is an explanatory diagram showing the measurement results of temperature and output current values. 【0009】Next, with reference to the attached drawings, an embodiment of the present invention will be described to facilitate understanding of the present invention. As shown in Figure 1, an electromotive force generating device 10 according to one embodiment of the present invention comprises an electrolyte-containing body 11 containing an electrolyte solution, a positive electrode 12 and a negative electrode 13, a power generation means 14 that generates an electromotive force when the positive electrode 12 and the negative electrode 13 come into contact with the electrolyte-containing body 11, and a container 16 that contains all or part of the electrolyte-containing body 11 together with water 15, which is an example of a liquid, in a sealed state. The electromotive force generating device 10 will be described in detail below. 【0010】 In this embodiment, as shown in Figure 1, the entire electrolyte-containing body 11 is housed in a container 16 together with the positive electrode 12 and the negative electrode 13. The container 16 only needs to be able to substantially seal the inside of the container 16, and its shape is not particularly limited. Here, sealing the inside of the container 16 means a state in which water 15 and the water vapor (gas) produced by the vaporization of water 15 are substantially prevented from leaving the container 16. The container 16 can be formed using, for example, metal, resin, or glass. 【0011】 Furthermore, the water 15 is absorbed by the liquid-absorbing member 17. In other words, the liquid-absorbing member 17 that absorbs the water 15 is placed inside the container 16. As the liquid-absorbing member 17, water-absorbing polymers such as sodium polyacrylate, potassium polyacrylate, and grafted water-absorbing polymers, as well as silica gel, zeolite, etc., can be used. 【0012】 In this embodiment, the liquid-absorbing member 17 is not in contact with any of the electrolyte-containing body 11, the positive electrode 12, or the negative electrode 13, and the water 15 does not come into contact with any of the electrolyte-containing body 11, the positive electrode 12, or the negative electrode 13. Furthermore, in this embodiment, the inside of the container 16 is divided into a space S1 in which the liquid-absorbing member 17 is located and a space S2 in which the electrolyte-containing body 11, the positive electrode 12, and the negative electrode 13 are located, by a permeable membrane 18 that allows water vapor from the vaporized water 15 to pass through but does not allow water 15 to pass through. As the permeable membrane 18, for example, a zeolite membrane or a film with minute pores can be used. 【0013】Therefore, even if there is water 15 in space S1 that has not been absorbed by the liquid-absorbing member 17, that water 15 will not penetrate space S2 beyond the permeable membrane 18, that is, the water 15 will not come into contact with any of the electrolyte-containing body 11, the positive electrode 12, or the negative electrode 13. Furthermore, by adjusting the type and size of the liquid-absorbing member 17 and the amount of water 15 placed in the container 16, it is possible, in principle, to achieve a state where all of the water 15 in the container 16 is absorbed by the liquid-absorbing member 17. 【0014】 The positive electrode 12 can be made of, for example, carbon-based materials such as carbon nanotubes (either SWNTs or MWNTs), carbon black, or carbon nanofibers, or substances with a low ionization tendency such as Au, Pt, Ag, or Cu (meaning substantially only these materials), or mostly these substances, i.e., carbon-based materials such as carbon nanotubes, carbon black, or carbon nanofibers, or Au, Pt, Ag, or Cu as the main components. The negative electrode 13 must be made of a substance with a certain or greater ionization tendency than the positive electrode 12, and can be made primarily of, for example, Li, Mg, Al, Zn, Fe, Ni, Sn, or Pb. 【0015】 In this embodiment, the electrolyte-containing body 11 is a component in which an electrolyte solution is distributed on one or more of the following materials: rubber, sponge, nonwoven fabric, and cloth (fabric). The electrolyte solution is a solution in which a water-soluble substance is dissolved in water. The electrolyte solution may also be a solution in which ions are dissolved in water. As the water-soluble substance, for example, one or more substances selected from the group consisting of calcium chloride, magnesium chloride, potassium carbonate, potassium pyrophosphate, magnesium perchlorate, calcium nitrate, magnesium nitrate, potassium acetate, urea, and potassium thiocyanate can be used. These substances are hygroscopic (it goes without saying that these substances are hygroscopic), and they can be dissolved in water at 20°C (H ２ The solubility in O) is 40 g / 100 g or more. 【0016】The water-soluble substance does not need to be hygroscopic; it just needs to be soluble in water (or a water-containing solution). For example, a substance with a solubility of 5 g / 100 g or more in water at 20°C can be used. Specifically, one or more substances selected from the group consisting of potassium benzoate, sodium dihydrogen phosphate, and citric acid may be used as the water-soluble substance. From the viewpoint of the electrolyte-containing body 11 efficiently absorbing water, the solubility of the water-soluble substance in water at 20°C is preferably 10 g / 100 g or more, more preferably 20 g / 100 g or more, and even more preferably 30 g / 100 g or more. 【0017】 In this embodiment, the power generation means 14 is composed of an electrolyte-containing body 11, a positive electrode 12, and a negative electrode 13. The power generation means 14 generates an electromotive force (electricity) when the positive electrode 12 and the negative electrode 13 come into contact with the electrolyte-containing body 11. Experiments have confirmed that when the humidity of the surrounding atmosphere of the electrolyte-containing body 11 decreases, the output current and output voltage of the power generation means 14 that is generating the electromotive force also decrease. This is thought to be due to the fact that the amount of electrolyte solution contained in the electrolyte-containing body 11 decreases as the humidity of the surrounding atmosphere decreases. 【0018】 In this regard, since the electromotive force generator 10 contains water 15 (or another liquid) in a sealed state within the container 16, the humidity inside the container 16 is maintained above a certain level, and the electrolyte-containing body 11 always contains a certain amount of electrolyte solution. Therefore, if all or part of the electrolyte-containing body 11 is contained in a sealed state within the container 16 together with water 15, it is possible to suppress the decrease in the output current and output voltage of the power generation means 14 due to a decrease in the humidity of the surrounding atmosphere of the container 16. When the entire electrolyte-containing body 11 is contained within the container 16, the output current and output voltage of the power generation means 14 are not substantially affected by the humidity of the surrounding atmosphere of the container 16. 【0019】In order for the electrolyte-containing body 11 to stably acquire moisture (water vapor) from inside the container 16, it is preferable that the water-soluble substance is hygroscopic, and more preferably deliquescent. In this embodiment, the entire electrolyte-containing body 11 is contained within the container 16, but even if only a portion (including most) of the electrolyte-containing body 11 is contained within the container 16 and the rest is exposed outside the container 16, the electrolyte-containing body 11 can still absorb water vapor from inside the container 16. 【0020】 For example, half of the electrolyte-containing body 11 may be housed inside the container 16, and the other half may be placed outside the container 16. In this case, the portion of the electrolyte-containing body 11 placed outside the container 16 can be covered with a film or coating agent to prevent drying, thereby preventing the water in the electrolyte solution contained in the electrolyte-containing body 11 from evaporating outside the container 16. 【0021】 However, even without employing a design to prevent drying of the portion of the electrolyte-containing body 11 that is located outside the container 16, if a portion of the electrolyte-containing body 11 is contained within the container 16 together with water 15, the influence of humidity in the surrounding atmosphere of the electromotive force generator 10 can be suppressed compared to a state where the entire electrolyte-containing body 11 is exposed to the outside. 【0022】 It goes without saying that in order for the electrolyte-containing body 11 to efficiently absorb water vapor from inside the container 16, it is preferable to place the entire electrolyte-containing body 11 inside the container 16. However, the positive electrode 12 and the negative electrode 13 may each be placed only partially inside the container 16, or the entire positive electrode 12 and the entire negative electrode 13 may be placed outside the container 16. For example, a portion of the electrolyte-containing body 11 may be placed outside the container 16, and the positive electrode 12 and the negative electrode 13, which are both placed outside the container 16, may be placed in contact with that portion. 【0023】 When a component containing an electrolyte solution is formed from a rubber material, the rubber material can be, for example, natural rubber, styrene-butadiene rubber, chloroprene rubber, acrylonitrile rubber, butyl rubber, ethylene-propylene rubber, ethylene-propylene-diene rubber, urethane rubber, silicone rubber, fluororubber, chlorosulfonated polyethylene rubber, acrylic rubber, isoprene rubber, or epichlorohydrin rubber. 【0024】 In this embodiment, the electrolyte solution is dispersed substantially uniformly in the electrolyte-containing body 11. When forming a member with a distributed electrolyte solution using a rubber material, the substantially uniform dispersion of the electrolyte solution can be achieved by a process of mixing and dispersing the carrier to which the electrolyte solution is attached with the rubber material before crosslinking. The carrier is, for example, one or more substances selected from the group consisting of zeolite, diatomaceous earth, shirasu balloon, carbon black, carbon nanotubes, graphene, silica gel, montmorillonite, kaolinite, pumice, shale, mesoporous silica, porous polymer beads, graphite, cellulose nanofiber, cork, and γ-alumina. Alternatively, the electrolyte solution may be distributed without using a carrier. 【0025】 Furthermore, in this embodiment, in the initial state, the positive electrode 12 is in close contact with the electrolyte-containing body 11, while the negative electrode 13 is not in contact with the electrolyte-containing body 11. Therefore, in the initial state, the power generation means 14 does not generate electromotive force. The electromotive force generator 10 is designed so that when a predetermined tilt occurs in the entire electromotive force generator 10 or a predetermined impact is applied, the negative electrode 13 comes into contact with the electrolyte-containing body 11, and the power generation means 14 begins to generate electromotive force. By designing it in this way, the generation of electromotive force (output current or output voltage) by the power generation means 14 makes it possible to detect when a predetermined tilt occurs in the electromotive force generator 10 (container 16) or when a predetermined impact is applied. 【0026】 Alternatively, in the initial state, the negative electrode 13 can be in contact with the electrolyte-containing material 11, while the positive electrode 12 is not in contact with the electrolyte-containing material 11. In this case, the positive electrode 12 can be made movable so that it comes into contact with the electrolyte-containing material 11 when a predetermined tilt or the like occurs in the electromotive force generator 10. Furthermore, if both the positive electrode 12 and the negative electrode 13 are in contact with the electrolyte-containing material 11 in the initial state, and one or both of the positive electrode 12 and the negative electrode 13 are designed to move away from the electrolyte-containing material 11 when a predetermined tilt or the like occurs in the electromotive force generator 10, it is possible to detect that a predetermined tilt or the like has occurred in the electromotive force generator 10 due to the cessation of the electromotive force generated in the power generation means 14. 【0027】For example, by designing the electromotive force generator 10 so that the negative electrode 13 can move along the rail, the negative electrode 13 can move and come into contact with the electrolyte-containing body 11 when the electromotive force generator 10 experiences a predetermined tilt (a tilt of a predetermined angle or more in a predetermined direction) or when the electromotive force generator 10 experiences a predetermined impact (an impact of a predetermined magnitude in a predetermined direction). 【0028】 Furthermore, the container 16 may be further equipped with a heating means for heating the inside of the container. This is based on experimental verification that heating the inside of the container 16 increases the output voltage and output current of the power generation means 14 when it is generating electromotive force. In other words, providing a heating means is preferable in that it increases the output voltage and output current of the power generation means 14. 【0029】 When the electromotive force generator 10 is used in an environment where power supply is difficult, it is preferable to use a heating means that generates heat through an exothermic reaction. For example, a heating means (such as quicklime) that generates heat when water 15 comes into contact with it can be used, and this heating means can be placed inside the container 16 (in this embodiment, inside space S1). In this way, the water 15 inside the container 16 can be used not only to maintain the humidity inside the container 16 above a certain level, but also for generating heat. 【0030】 However, in order to maintain heating inside the container 16 by the exothermic reaction for a long period of time, it is necessary to prepare a large amount of heating means and water 15, for example, so that the heating means, which is not generating an exothermic reaction, comes into contact with the water 15 many times. In this respect, as in this embodiment, if the power generation means 14 does not normally generate electromotive force, but generates electromotive force only when a predetermined phenomenon occurs, then it is sufficient to have the heating means generate heat only at the timing when the power generation means 14 generates electromotive force, and it is not necessary to maintain heating inside the container 16 for a long period of time. 【0031】 For example, if the power generation means 14 generates an electromotive force only when the container 16 is tilted to a predetermined degree, the design should be such that the water 15 comes into contact with the heating means when the container 16 is tilted to that degree. Similarly, if the power generation means 14 generates an electromotive force only when the container 16 is subjected to a predetermined impact, the design should be such that the water 15 comes into contact with the heating means when the container 16 is subjected to that impact. 【0032】 When the container 16 is tilted to a predetermined angle or subjected to a predetermined impact, the water 15 may come into contact with the heating means. In this case, both the positive electrode 12 and the negative electrode 13 may be in contact with the electrolyte-containing material 11 in the initial state. In this case, as the inside of the container 16 is heated due to the container 16 tilting to a predetermined angle, the output current and output voltage of the power generation means 14 will increase. Therefore, this increase in output current, etc., can be used to detect that the container 16 has tilted to a predetermined angle. Alternatively, the heating means may be made to generate heat due to phenomena other than exothermic reactions (for example, frictional heat). Experimental example 【0033】 Next, we will describe two experiments conducted to confirm the effects of the present invention. In the first experiment, three samples were prepared in which the positive electrode was a sheet formed of carbon nanotubes and the negative electrode was a magnesium plate. Each sample contained an electrolyte containing silicone rubber as the main component. The electrolyte containing each sample contained the following water-soluble substances. 【0034】 Sample 1: Potassium acetate Sample 2: Magnesium nitrate Sample 3: Magnesium chloride 【0035】 For each of the three samples described above, the sample was left standing for two weeks in an environment of 23°C and 20% relative humidity (hereinafter referred to as the "dry environment") with the positive electrode in contact with the electrolyte-containing material and the negative electrode not in contact with the electrolyte-containing material. After that, the output current value of the sample was measured with both the positive and negative electrodes in contact with the electrolyte-containing material. Next, the sample was left standing for two weeks in an environment of 23°C and 80% relative humidity (hereinafter referred to as the "humid environment") with the positive electrode in contact with the electrolyte-containing material and the negative electrode not in contact with the electrolyte-containing material. After that, the output current value of the sample was measured with both the positive and negative electrodes in contact with the electrolyte-containing material. The measured output current values ​​were as follows. 【0036】 <Sample 1> Dry environment 0.07 mA, Humid environment 0.5 mA, Humid environment / Dry environment ≈ 714% 【0037】<Sample 2> Dry environment 0.01 mA, Humid environment 0.4 mA, Humid environment / Dry environment = 4000% 【0038】 <Sample 3> Dry environment 0.15 mA, Humid environment 0.7 mA, Humid environment / Dry environment ≈ 467% 【0039】 In the second experiment, a sample was used in which the positive electrode was a plate made of graphite, the negative electrode was a plate made of magnesium, and the electrolyte contained silicone rubber with potassium acetate distributed within it. This sample was placed in a lidded container along with water in an open-topped container (in a nearly sealed state), and the lidded container was placed in a constant-temperature furnace. While the temperature inside the constant-temperature furnace was changed, the temperature inside the lidded container was measured using a thermocouple, and the output voltage of the sample was measured using a voltmeter. 【0040】 The measurement results are shown in Figure 2. From the measurement results shown in Figure 2, it was confirmed that the output voltage of the sample increased with the temperature inside the lidded container and decreased with the temperature decreasing. The horizontal axis in Figure 2 indicates the date and time the measurement was performed. 【0041】 Although embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and any changes to the conditions, etc., that do not depart from the gist of the invention are all within the scope of application of the present invention. For example, it is not necessary to house a liquid-absorbing member in the container. A container with an opening that holds water may be placed inside the container, or a water reservoir may be formed to store water inside the container. Furthermore, the permeable membrane can be omitted. Moreover, if a permeable membrane is used, the liquid-absorbing member may not be provided. For example, the above-described container may be placed in space S1 or the above-described water reservoir may be formed, and water, which is an example of a liquid, may be placed in space S1. 【0042】 The output current and output voltage of the electromotive force generator according to the present invention are less affected by the ambient humidity of the installation location of the electromotive force generator, making it usable in a variety of environments. 【0043】 10: Electromotive force generator, 11: Electrolyte-containing body, 12: Positive electrode, 13: Negative electrode, 14: Power generation means, 15: Water, 16: Container, 17: Liquid-absorbing member, 18: Permeable membrane, S1, S2: Space

Claims

1. An electromotive force generating device comprising: an electrolyte-containing body containing an electrolyte solution, a positive electrode and a negative electrode, wherein the positive electrode and the negative electrode come into contact with the electrolyte-containing body to generate an electromotive force; and a container in which all or part of the electrolyte-containing body is contained together with the liquid in a sealed state.

2. The electromotive force generating device according to claim 1, characterized in that an absorbent member that absorbs the liquid is disposed inside the container.

3. The electromotive force generating device according to claim 1 or 2, characterized in that the inside of the container is divided into a space S1 in which the liquid is disposed and a space S2 in which the electrolyte-containing material is disposed, by a permeable membrane that allows the vaporized gas of the liquid to pass through but does not allow the liquid to pass through.

4. The electromotive force generating device according to claim 1 or 2, further comprising a heating means for heating the inside of the container.

5. The electromotive force generating device according to claim 4, characterized in that the heating means generates heat by an exothermic reaction.

6. The electromotive force generating device according to claim 4, characterized in that the heating means is arranged inside the container and generates heat when it comes into contact with the liquid.

7. The electromotive force generating device according to claim 6, characterized in that the liquid comes into contact with the heating means when the container is tilted.

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