Method for creating separator plate for fuel cells configured by covering entire sheet-like compact consisting of synthetic resin with set of aggregates of carbon blacks bonded by frictional pressure contact

Abstract

To form a passage, in which a carbon-based material is continued, on a substrate of a synthetic resin, cover the entire substrate of the synthetic resin with the carbon-based material, and bond the carbon-based material to the substrate of the synthetic resin with a large bonding force.SOLUTION: A compact of a synthetic resin is molded in which a plurality of grooves where a hydrogen gas passes is formed on one face and a plurality of grooves where an oxygen gas or air passes is formed on the other face. Next, a carbon black immersed in methanol is crushed into a critical size, an impulse wave is applied by a homogenizer device, aggregates are entangled with each other via the methanol, further, alcohol of which the viscosity is higher than that of methanol is mixed, and a suspension liquid is prepared. The compact is immersed in the suspension liquid, the compact is extracted, and a temperature is raised to a boiling point of alcohol. Thereafter, a front face and a side face of the compact are compressed, a set of aggregates in frictional pressure contact are brought into frictional pressure contact with the entire compact, and a separator plate consisting of the compact of the synthetic resin to which conductivity is imparted is created by the set of aggregates.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] In the present invention, the following processes are carried out in succession to produce a sheet-shaped fuel cell separator plate. First, a sheet-like molding is formed from a synthetic resin, with a plurality of grooves formed on one surface through which hydrogen gas passes and a plurality of grooves formed on the other surface through which oxygen gas or air passes. next, Size Sheet-shaped molding Size The thickness is the same as that of the sheet-shaped molded body, and the thickness is thicker than that of the sheet-shaped molded body, and a plurality of grooves through which hydrogen gas passes are formed in the sheet-shaped molded body. was formed The plurality of grooves are and A first plate material made of synthetic resin is molded, on which a plurality of overlapping projections are formed. moreover, Size Sheet-shaped molding Size The thickness is the same as that of the sheet-shaped molded body, and the thickness is thicker than that of the sheet-shaped molded body, and a plurality of grooves through which oxygen gas or air passes are formed on the sheet-shaped molded body. was formed The plurality of grooves are and A second plate made of synthetic resin is molded, on which a plurality of overlapping projections are formed. Thereafter, a third plate that covers the entire carbon black clusters immersed in methanol is placed over the carbon black clusters, and the entire surface of the third plate is uniformly compressed to crush the carbon black clusters. Furthermore, vibration acceleration in three directions is repeatedly applied to the crushed carbon black clusters, and the crushed carbon black clusters are rearranged in the methanol. These paired processes of applying a compressive load and applying vibration acceleration are repeated to crush the carbon black clusters immersed in the methanol to their limit size. Furthermore, a homogenizer is operated in the methanol, and shock waves are repeatedly applied via the methanol to the crushed carbon black clusters, separating the entanglements between the carbon black aggregates and entangling the aggregates via the methanol. Furthermore, Through methanol A collection of entangled aggregates is dispersed in methanol to prepare a suspension. Further, an alcohol that is soluble or miscible in methanol, has a viscosity 9-20 times that of methanol, and has a boiling point higher than that of methanol but lower than 200°C is mixed with the suspension in such a ratio that the viscosity of the suspension increases 5-10 times; Through a solution in which alcohol is dissolved in methanol or a mixture in which alcohol is mixed with methanol The entangled aggregates have a viscosity of 3-6 mPa·sec at 20°C. Alcohol dissolved in methanol or mixed with methanol A new suspension is prepared by dispersing the After this, a new suspension is poured into a container whose bottom shape is slightly larger than the sheet-shaped compact, and the sheet-shaped compact is then poured into the new suspension. Medium Immerse in. Furthermore, a first plate member is attached to a container having a rectangular bottom surface, and each plate member constituting four side surfaces of the container has a function of moving parallel to the inside of the container in a direction perpendicular to the side surface. 、 Multiple protrusions on top facing Then, a new suspension Medium The sheet-like molded body is immersed in The aforementioned The first plate has a plurality of protrusions. Applicable The sheet-like molded body has multiple grooves through which hydrogen gas passes, which overlap each other. Applicable The sheet-like molded body is placed on the first plate. Applicable The second plate has a plurality of protrusions. The aforementioned The sheet-like molded body is formed so that the grooves through which oxygen gas or air passes overlap each other. Applicable A second plate is placed on the sheet-like molded body. Then, a compressive load is evenly applied to the entire surface of the second plate, and the container is heated to the boiling point of the alcohol. Then, the plates constituting the upper and lower sides of the container are simultaneously moved in parallel toward the inside of the container. The plate material Sheet-shaped molded body come into contact with The upper and lower plates are then returned to their original positions. Furthermore, the left and right plates are simultaneously translated inwardly of the container. The plate material is Rod-shaped molding come into contact withThe left and right side surfaces are compressed with a compressive stress equivalent to the compressive load, and then the plates constituting the left and right side surfaces are returned to their original positions. Surface Compressive stress is applied to the entangled aggregates that cover the entire structure. Applicable The intertwined aggregates are friction-welded together, and the friction-welded aggregates form a sheet-like compact. Surface The entire surface is friction-welded to form a sheet-like compact. Surface The whole is covered with a collection of aggregates that are joined by friction welding. After this, the same adhesive is applied to multiple locations on the bottom of the container. Size The impact acceleration is simultaneously applied to the first plate member and the second plate member, and the sheet-like compact covered with a collection of aggregates bonded to both the first plate member and the second plate member is peeled off from the container. Further, the first plate member is subjected to impact acceleration at multiple locations on the bottom surface thereof. Same size as above Identical Size The sheet-like compact covered with aggregates is peeled off from the first plate material by applying impact acceleration simultaneously, and finally, the sheet-like compact covered with aggregates is peeled off from the first plate material at multiple locations on the surface of the second plate material. Same size as above Identical Size At the same time, an impact acceleration is applied, and the sheet-like compact covered with aggregates is peeled off from the second plate material. The result is a fuel cell separator plate covered with a collection of friction-welded aggregates.

[0002] The inventors have filed patent application No. 2021-035897 for an invention relating to a method for repeatedly adsorbing carbon black aggregates onto synthetic resin pellets and using the collection of synthetic resin pellets to form a molded body having the shape of a fuel cell separator plate. The present invention differs from the prior application in that a sheet-like molded body made of synthetic resin that constitutes the fuel cell separator plate is prepared in advance, and a collection of aggregates joined by friction welding is friction-welded to the front and side surfaces of the sheet-like molded body. Therefore, the fuel cell separator plate of the present invention can be prepared more cheaply than the fuel cell separator plate of the prior application. Furthermore, because the synthetic resin sheet-like molded body is prepared in advance, there are no restrictions on the material and shape of the molded body. [Background technology]

[0003] Polymer electrolyte fuel cells are being considered for use as power sources for electric vehicle power generation systems, home cogeneration systems, and portable devices such as personal computers. Polymer electrolyte fuel cells are constructed by stacking unit cells in a series arrangement to generate a large electromotive force. Separator plates are used to separate these unit cells. For example, one electric vehicle may require as many as 400 separator plates. Therefore, separator plates account for the majority of the weight and cost of a fuel cell. Therefore, to popularize polymer electrolyte fuel cells, it is essential to significantly reduce both the cost and weight of separator plates. On the other hand, separator plates are required to have the functions of electrical conductivity, gas impermeability, corrosion resistance, strength, gas supply ability, and low cost. First, the electrical resistance of separator plates contributes to power generation loss and heat generation in polymer electrolyte fuel cells. Because heat generation shortens the battery's lifespan, it is necessary to increase the battery's cooling capacity. Adding a cooler further increases the battery's weight and manufacturing costs. Incidentally, the U.S. Department of Energy requires separator plates to have an electrical resistance of 20 Ωcm or less. However, automotive fuel cells require a power generation capacity of around 90 kW. For example, in a 300-volt, 300-ampere fuel cell, if a material with an electrical resistance of 20 Ωcm is used, the resistance when current flows through 400 separator plates, each 2 mm thick and with an A-4 area, is only 0.0026 Ω. However, if 300 amperes of current flows through these separator plates, a voltage loss of 0.8 volts occurs, resulting in an internal loss of 240 watts and heat generation. This necessitates the use of a cooler to increase the battery's cooling capacity. Therefore, the lower the separator plate's electrical resistance, the better. Secondly, hydrogen gas and oxygen gas (or air) flow on the front and back of the separator plate, and if the hydrogen gas and oxygen gas (or air) mix together, it can cause an explosion and fuel loss. For this reason, the separator plate is required to be gas impermeable at atmospheric pressure. Incidentally, the gas impermeability required for separator plates by the US Department of Energy is 2 x 10-6 cm 3 / cm 2 / second. Third, the principle of power generation in fuel cells is the use of protons (H + ) moves from the fuel electrode to the oxygen electrode. For this reason, power generation occurs in a highly oxidizing environment, requiring the separator plate to have high corrosion resistance. The metals that can be used in this environment are limited to gold and platinum due to their high corrosion potential. Therefore, the metal used for the separator plate must be gold-plated, which increases the manufacturing cost of the separator plate. Furthermore, if metal ions dissolve into the battery, the dissolved metal ions will reduce the power generation capacity of the polymer membrane. For this reason, the metal used for the separator plate must be gold-plated. Fourth, fuel cells in automobiles must be resistant to the impact of a collision. This requires the separator plates to be strong. However, increasing the separator plate thickness to increase its strength increases the weight of the separator plate. Fifth, the separator plate has the function of supplying hydrogen gas and oxygen gas (or air) to the polymer membrane. For this reason, the separator plate needs to be able to supply gas. In many cases, grooves are formed in the separator plate to serve as gas supply passages. Sixth, a key technology for the widespread use of electric vehicles is a significant reduction in the manufacturing costs of polymer electrolyte fuel cells. Therefore, in order to popularize electric vehicles, it is necessary to significantly reduce the cost of currently developed separator plates. Therefore, it is necessary to develop new separator plates that are completely different in configuration and structure from those currently being developed. The materials for separator plates currently being developed are roughly divided into metal-based and carbon-based. From the viewpoints of weight reduction, reduction in manufacturing costs, and ensuring corrosion resistance, separator plates made of a synthetic resin substrate with a carbon-based material to provide conductivity are superior to separator plates made of other materials. In other words, the density of general-purpose synthetic resins is 0.9-1.6 g / cm. 3 The density of aluminum is 2.7 g / cm 3The cost of molding a separator plate from synthetic resin is lower than the cost of processing a separator plate from metal. Furthermore, general-purpose carbon materials such as carbon black and graphite particles are cheaper than metal particles. Carbon materials also have corrosion resistance that is comparable to that of metals. Yo Superior.

[0004] As a conventional example of imparting conductivity to a synthetic resin substrate by using a carbon-based material, for example, there is the following conventional technology. Patent Document 1 describes separator plates in which a conductive composition is spray-coated onto the uneven surface of a substrate made of various synthetic resins. The conductive composition uses a resin such as epoxy resin, silicone resin, polyimide resin, phenolic resin, or acrylic resin as a binder, and conductive carbon powder or metal powder such as Ag, Cu, or Ni is dispersed in this binder. However, simply dispersing conductive carbon powder or metal powder in a synthetic resin binder does not improve the conductivity of the separator plate unless the conductive carbon powder or metal powder is continuously bonded to form a path for current flow. Therefore, the electrical resistance of the synthetic resin binder becomes dominant, resulting in poor conductivity of the separator plate. To improve the conductivity of the separator plate, the filling rate of the conductive carbon powder or metal powder must be increased. However, increasing the filling rate of these solids makes spray coating difficult. Furthermore, the use of metal powder dissolves the metal powder that appears on the surface, which accelerates internal corrosion of the separator plate.

[0005] Patent Document 2 describes a conductive separator plate that is a composite of a non-carbonaceous resin made of synthetic resin and a conductive agent made of spherical graphite, graphite powder with an aspect ratio of 2.0 or less, and conductive carbon black. However, even if a conductive agent is simply mixed with a non-carbonaceous resin and molded into a compact, unless the conductive agent is continuously bonded and a path for current flow is formed in the compact, the electrical resistance of the non-carbonaceous resin becomes dominant and the conductivity of the separator plate does not improve. On the other hand, if the filling rate of the conductive agent is increased to improve the conductivity of the separator plate, molding the non-carbonaceous resin becomes difficult. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2004-079536 [Patent Document 2] WO99 / 49530 DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0007] The following six challenges arise when forming a separator plate that provides conductivity using a carbon-based material on a substrate made of synthetic resin. First, there is a challenge to make the electrical resistance of the separator plate closer to that of the carbon-based material, by forming continuous paths in the synthetic resin substrate through which electrons move, and by doing so, the electrical resistance of the synthetic resin substrate becomes closer to that of the carbon-based material. On the other hand, as explained in paragraphs 4 and 5, simply mixing a conductive material into an insulating material does not allow the conductive materials to bond or come into contact with each other and form a continuous path for electrons to move in the synthetic resin substrate. In contrast, if the entire synthetic resin substrate can be covered with a highly conductive carbon-based material, the carbon-based material will form a continuous path in the synthetic resin substrate, and the electrical resistance of the synthetic resin substrate will approach the electrical resistance of the carbon-based material. Therefore, the second challenge is to find an inexpensive method for covering the entire synthetic resin substrate with a highly conductive carbon-based material. Furthermore, the separator plate has the function of supplying hydrogen gas and oxygen gas (or air) to the polymer membrane. Therefore, the third challenge is to ensure that the highly conductive carbon-based material covering the synthetic resin substrate does not hinder the movement of hydrogen gas and oxygen gas (or air), and that the grooves in the synthetic resin substrate can supply hydrogen gas and oxygen gas (or air) to the polymer film. Furthermore, the separator plates must be strong enough not to break even when subjected to an impact force. Therefore, the fourth challenge is that the synthetic resin substrate must be able to withstand impact when subjected to an impact force. For this reason, the substrate must be molded from a synthetic resin with high impact strength. Furthermore, it is necessary that the highly conductive carbon-based material does not peel off from the synthetic resin substrate when subjected to an impact force. For this reason, it is necessary for the highly conductive carbon-based material to be bonded to the substrate with a large bonding strength using the synthetic resin. Furthermore, if the highly conductive carbon-based material covering the synthetic resin substrate is lightweight, the impact force received by the highly conductive carbon-based material will be small. For this reason, it is necessary for the highly conductive carbon-based material covering the synthetic resin molded body to be lightweight. Furthermore, if the highly conductive carbon-based material can elastically deform when subjected to an impact force, the highly conductive carbon-based material can withstand the impact force. For this reason, it is necessary for the highly conductive carbon-based material to be able to elastically deform when subjected to an impact force. Furthermore, in order to popularize fuel cells, it is required that the weight of the separator plate is significantly lighter than that of conventionally developed separator plates, and that the manufacturing cost of the separator plate is significantly lower than that of conventionally developed separator plates. Therefore, the fifth challenge is to make the separator plate using extremely simple processes, and all materials used must be inexpensive, general-purpose industrial materials.Furthermore, the synthetic resin substrate and the highly conductive carbon-based material covering the substrate must be lightweight. The problem to be solved by the present invention is to solve the above five problems and to find a method for producing a separator plate made of a substrate of a synthetic resin to which electrical conductivity has been imparted. [Means for solving the problem]

[0008] Sheet-shaped molded body made of synthetic resin Surface A method for making a separator plate for a fuel cell, the separator plate being entirely covered with a collection of friction-welded carbon black aggregates, comprises the steps of: a first step of molding a sheet-like molded body made of synthetic resin, the sheet-like molded body having a plurality of grooves formed on one surface through which hydrogen gas passes and a plurality of grooves formed on the other surface through which oxygen gas or air passes; Size The sheet-like molded body Size The thickness is the same as that of the sheet-shaped molded body. Thickness of A plurality of grooves formed in the sheet-like molding, through which hydrogen gas passes, are formed. was formed The plurality of grooves are and a second step of molding a first plate material made of synthetic resin on which a plurality of overlapping projections are formed; Size The sheet-like molded body Size The thickness is the same as that of the sheet-shaped molded body. Thickness of A plurality of grooves formed in the sheet-like molding, through which oxygen gas or air passes, are formed. was formed The plurality of grooves are and a third step of molding a second plate material made of synthetic resin on which a plurality of overlapping projections are formed; a carbon black aggregate and a weight of the carbon black aggregate Composed of weightMethanol is poured into a first container, and the methanol is stirred to prepare a first suspension in which the carbon black clumps are immersed in the methanol. Thereafter, a third plate that covers the entire surface of the first suspension is placed on top of the first suspension. A compressive load is applied evenly to the entire surface of the third plate to crush the carbon black clumps immersed in the methanol. The first container is placed on a vibration table of a vibrator, and the vibrator is operated to repeatedly apply vibration accelerations in three directions, i.e., front-to-back, left-to-right, and up-to-down, to the first container to rearrange the crushed carbon black clumps in the methanol. Thereafter, the compressive load is again applied evenly to the entire surface of the third plate to further crush the crushed carbon black clumps in the methanol. The vibration accelerations in the three directions are again repeatedly applied to the first container. These paired processes consisting of the process of applying the compressive load and the process of applying the vibration acceleration are repeated, and when the compressive load is applied to the third plate, When the carbon black has been crushed to a size limit, even if the crushed carbon black is compressed, no compressive stress is applied to the finely divided carbon black, so the finely divided carbon black is not crushed and a repulsive force is generated in the third plate material. a fourth step of determining that the crushing of the carbon black aggregates in methanol is completed when a repulsive force is generated in the third plate material and stopping the pair of treatments, and then removing the third plate material from the first container; In the first container Ultrasonic method A homogenizer is placed and operated in the first suspension, and shock waves are repeatedly applied to the aggregates of the crushed carbon black via the methanol, entangling aggregates in the crushed carbon black via the methanol, and Through methanol a fifth step of preparing a second suspension in which a collection of entangled aggregates is dispersed in the methanol; An alcohol having three properties, namely, a first property of being soluble or miscible in methanol, a second property of having a viscosity 9 to 20 times that of methanol, and a third property of having a boiling point higher than that of methanol but lower than 200°C, is mixed with the second suspension, and the alcohol 、 The solution dissolved in methanol or The methanolThe viscosity of the mixed liquid is increased to 3-6 mPa·sec at 20°C, and Through methanol A collection of entangled aggregates is entangled via the dissolving solution or the mixed solution, and Through the dissolving solution or the mixture a sixth step of preparing a third suspension in which a collection of entangled aggregates is dispersed in the solution or the mixture; The third suspension is poured into a second container having a bottom surface slightly larger than the sheet-like compact produced in the first step, and the sheet-like compact is then immersed in the third suspension. Medium a seventh step of immersing the The first plate material made in the second process is placed on a third container in which each plate material constituting the four side surfaces of the container has a function of moving parallel to the inside of the container in a direction perpendicular to the side surface, and the plurality of protrusions formed on the first plate material are placed on the third container. facing Furthermore, the third suspension is arranged so that the plurality of grooves formed on the sheet-like compact through which hydrogen gas passes overlap with the plurality of protrusions formed on the first plate material. Medium The sheet-like molded body immersed in the above-mentioned solution is placed on the first plate material, and the plurality of protrusions formed on the second plate material prepared in the third step are fitted into the plurality of grooves formed on the sheet-like molded body through which oxygen gas or air passes. and The second plate is placed in the third suspension so as to overlap. Medium a sheet-like formed article immersed in the alcohol is placed on the second plate member; a compressive load is then evenly applied to the entire surface of the second plate member, and the temperature of the third container is raised to the boiling point of the alcohol; and the plate members constituting the upper and lower side surfaces of the third container are simultaneously translated toward the inside of the third container; The plate material The third suspension Medium Sheet-shaped compact immersed in come into contact with the upper and lower plates constituting the side surfaces are compressed with a compressive stress corresponding to the compressive load, and then the plates constituting the upper and lower side surfaces are returned to their original positions; and the plates constituting the left and right side surfaces of the third container are simultaneously translated toward the inside of the third container; The plate material The third suspension Medium Sheet-shaped compact immersed in come into contact withThe surfaces are compressed with a compressive stress equivalent to the compressive load, and then the plate members constituting the left and right side surfaces are returned to their original positions, thereby First, the adhesive layer adhered to the entire surface of the sheet-like molded body was the methanol and the alcohol are evaporated from the third suspension; Applicable Sheet-shaped molding Surface The whole is covered with a mass of intertwined aggregates. R , Next The surface of the sheet-like molded body The entire Compressive stress is applied to the sheet-like molded body. The entire surface of Covered The aggregates in the entangled collection The entangled aggregates are friction-welded together, and the compressive stress is applied to the friction-welded aggregates, causing the friction-welded aggregates to adhere to the surface of the sheet-like compact. The whole of and friction-pressure welding the sheet-shaped molded body to the Surface an eighth step in which the entire structure is covered with a collection of friction-welded aggregates; The third container has a bottom surface at a plurality of locations. Consists of size Impact acceleration is applied simultaneously to the first plate material and the second plate material, and the aggregates sandwiched between the two plates and bonded to the two plates are The entire surface The covered sheet-like molded body is peeled off from the third container, and the first plate member is coated with the above-mentioned adhesive at a plurality of locations on the bottom surface thereof. Impact acceleration the same size as Consists of Identical Size The impact acceleration is applied simultaneously to the aggregates. The entire surface The covered sheet-like molded body is peeled off from the first plate material, and finally, the above-mentioned Impact acceleration the same size as Consists of Identical Size The impact acceleration is applied simultaneously to the aggregates. The entire surface a ninth step of peeling the covered sheet-like molded body from the second plate material; By carrying out all of these nine processes continuously, The entire surface of the sheet-shaped molded product made of synthetic resin is Covered with a collection of friction-welded aggregates Composed of Fuel cell separator plates but create AndA method for producing a separator plate for a fuel cell 。

[0009] By continuously performing all of the nine steps described below, a sheet-shaped fuel cell separator plate covered with a collection of friction-welded aggregates is produced. Here, the nine steps and their effects are explained. In the first step, a sheet-like molded body is formed from a synthetic resin, with a plurality of grooves formed on one surface through which hydrogen gas passes and a plurality of grooves formed on the other surface through which oxygen gas or air passes. This allows inexpensive sheet-like molded bodies to be produced continuously. On the other hand, if a sheet-like molded body can be molded, there is no restriction on the material of the synthetic resin, but Fuel cells are a hit The greater the impact strength, the greater the impact strength of the fuel cell separator plate. For this reason, fuel cell separator plates that require high impact strength are made of synthetic resins with excellent impact strength. Made of synthetic resin There are no restrictions on the shape and size of the sheet-shaped molded body. Fuel cell separator plates are required to be light and thin. For this reason, a thickness of 1.5-3 mm is appropriate. This results in a fuel cell separator plate that is lighter and thinner than conventional fuel cell separator plates. On the other hand, a groove depth of 0.5-2.0 mm is appropriate, and it is desirable to provide grooves so that the groove positions on the front and back surfaces do not overlap. Groove shapes vary, and multiple grooves can be formed by molding synthetic resin. Molded body Front and back and The groove shape and Groove Therefore, unlike when forming grooves by machining, the shape and Groove The processing cost does not increase depending on the number of pieces. The shape of the groove is For example, there are various shapes, such as a shape in which one continuous groove goes around the entire surface of the sheet-like molded body in concentric circles, a shape in which one continuous groove bends 180 degrees near both ends of the sheet-like molded body, and multiple linear grooves are formed in parallel at equal intervals, a shape in which one continuous groove looks like gradually decreasing squares of different sizes going around the entire surface of the sheet-like molded body, and a shape in which multiple linear grooves are formed in parallel at equal intervals. A groove with a unique shape is formed in tree It is sufficient if hydrogen gas and oxygen gas or air can pass through the grooves. In the second step, Size Sheet-shaped molding Size The thickness is the same as that of the sheet-shaped molded body, and the thickness is thicker than that of the sheet-shaped molded body, and a plurality of grooves through which hydrogen gas passes are formed in the sheet-shaped molded body. was formed The plurality of grooves are and A first plate material made of synthetic resin having a plurality of overlapping projections formed thereon is molded. Through alcohol The entangled aggregates are adsorbed onto the surface of the sheet-like compact. In the eighth step, the sheet-like compact is sandwiched between the first plate and the second plate formed in the third step, and the surface of the second plate is adsorbed. of Evenly distribute the whole etc. Compressed to At the same time, the temperature rises to the boiling point of the alcohol. . As a result, the entire surface of the sheet-like compact is covered with a collection of entangled aggregates, and further A collection of entangled aggregates Comrades A collection of intertwined aggregates joined by friction welding. but , friction welding to a sheet-shaped compact vinegar Therefore, as long as the first plate material can be molded, there are no restrictions on the synthetic resin material. Similarly, as long as the second plate material can be molded, there are no restrictions on the synthetic resin material. Furthermore, since multiple protrusions are formed simultaneously by molding the synthetic resin, the shape of the protrusions and Protrusion number and There are no restrictions on the number and shape of the protrusions, and the molding cost does not depend on the shape and number of the protrusions. Furthermore, the multiple protrusions formed on the first plate overlap with the multiple grooves formed in the sheet-like molded body, so they must match the shape of the multiple grooves in the sheet-like molded body that was molded earlier. Therefore, a protrusion height of 0.5-2.0 mm is appropriate. In the third step, Size Sheet-shaped molding Size The thickness is the same as that of the sheet-shaped molded body, and the thickness is thicker than that of the sheet-shaped molded body, and a plurality of grooves through which oxygen gas or air passes are formed on the sheet-shaped molded body. was formed The plurality of grooves are andA second plate made of synthetic resin is formed with a plurality of overlapping protrusions. The plurality of protrusions formed on the second plate overlap with the plurality of grooves formed in the sheet-like molding, so they are aligned with the shape of the plurality of grooves in the previously molded sheet-like molding. For this reason, the height of the protrusions is preferably 0.5-2.0 mm. In the fourth step, the carbon black aggregates are immersed in methanol and crushed to a limit size in the methanol. Composed of weight Methanol is poured into a first container and stirred to prepare a first suspension in which carbon black clumps are immersed in methanol. In other words, by compressing the carbon black clumps immersed in methanol, the carbon black clumps can be easily crushed, and the crushed carbon black is dispersed in methanol. By repeatedly crushing the carbon black clumps, the carbon black clumps are further crushed. Thereafter, a third plate material that covers the entire surface of the first suspension is placed on top of the first suspension, and a compressive load is applied evenly to the entire surface of the third plate material. etc. Furthermore, the third plate material is lifted from the first suspension, and the first container is placed on the vibration table of the vibration exciter. The vibration exciter is operated, and the first container is vibrated in three directions, i.e., forward and backward, left and right, and up and down. vibration Acceleration is repeatedly applied to rearrange the crushed carbon black clusters in the methanol. In other words, there is variation in the size of the carbon black in the carbon black clusters, and the size of the crushed carbon black also varies. As a result, voids are formed in the crushed carbon black clusters. To fill these voids, the crushed carbon black clusters are rearranged and crushed again, which progresses the crushing of all the carbon black and makes it possible to make the size of the crushed carbon black closer to uniform. Furthermore, a third plate is placed over the first suspension again, and the compressive load is again uniformly applied to the entire surface of the third plate. etc.In addition, the carbon black aggregates immersed in methanol are further crushed. Furthermore, the third plate material is again pulled out from the first suspension and placed in the first container. vibration The acceleration is then applied again and again. vibration A pair of processes consisting of a process of applying an acceleration and a process of applying a compressive load to the third plate is repeated, and when a repulsive force is generated in the third plate when a compressive load is applied to the third plate, it is determined that the crushing of the carbon black mass immersed in methanol has been completed, and the pair of processes is stopped. After this, the third plate is removed from the first container. In other words, when the carbon black has been crushed to a limit size, even if the crushed carbon black is compressed, no compressive stress is applied to the finely divided carbon black, and therefore the finely divided carbon black is not crushed. When a compressive load was applied to the third plate, A repulsive force is generated in the third plate. At this point, it is determined that the carbon black clumps have been crushed to a size approximately 1 / 25 of their original size. The smallest unit of carbon black is the aggregate, which is a primary agglomeration of carbon particles. In carbon black, this aggregate is a collection of carbon particles, each 10-100 nm in size, bound together in an irregular, complex, string-like structure (called a "structure"). Aggregates range in size from 100-500 nm and contain 100-1000 carbon particles. Therefore, aggregates are extremely lightweight and can be cut. These aggregates easily become entangled by the structure, forming agglomerates, which are secondary agglomerations of carbon particles and aggregate clusters. Therefore, crushing carbon black also crushes the agglomerates, reducing their size to approximately 1 / 25 of their original size. Furthermore, the aggregates are also cut into lengths shorter than 0.2 mm. In addition, by cutting the aggregates, after the methanol and alcohol are evaporated in the eighth step, the aggregates are randomly stacked with a high degree of integration to form a sheet-like compact. The entire surface ofFurthermore, the aggregates precipitate in layers. The aggregates that are piled up and precipitated are compressed as a whole, and in the aggregates that are piled up at a high density, all of the aggregates are friction-welded together. Furthermore, the friction-welded aggregates are friction-welded to the sheet-shaped compact. This results in a high bonding strength between the friction-welded aggregates and the sheet-shaped compact. Furthermore, because the friction-welded aggregates are thin (3-6 μm) and extremely lightweight, even if they are subjected to an impact force, they will not be peeled off from the sheet-shaped compact. In the fifth step, Through methanol A second suspension is prepared in which the entangled aggregates are dispersed in methanol. This dissociates the aggregates in the crushed carbon black. In other words, all the aggregates are joined together by friction welding, and the friction-welded aggregates are then molded into a sheet-like compact. The entire surface ofTo achieve friction welding, the aggregates in the crushed carbon black are first separated from each other. Note that the entanglement between the aggregates is merely a result of the aggregates being in contact with each other, and the bonding strength between the entangled aggregates is extremely weak. Carbon black is largely composed of agglomerates, which are aggregate clusters, and the largest aggregates are powders measuring nearly 1 mm. This makes it difficult to create a suspension of the agglomerates dispersed in methanol, and even more difficult to bond the agglomerates together by friction welding. For this reason, a homogenizer is operated in methanol, and shock waves are continuously applied to the crushed agglomerates. The shock waves separate the entangled aggregates, allowing the separated aggregates to adsorb methanol, entangling them through the methanol. Because the carbon black was crushed to its physical limit, the aggregates were cut to lengths shorter than 0.2 mm. Therefore, by continuously applying shock waves, the entanglement between the aggregates can be easily released. As a result, the aggregates become entangled with each other through methanol, and by continuously applying shock waves, Through methanol A second suspension is formed in which the entangled aggregates are dispersed in low viscosity methanol. That is, the entanglement of the aggregates is temporarily separated, and then the aggregates are entangled with each other through methanol, whereby the second suspension is easily formed. For this purpose, in the first container Ultrasonic methodA homogenizer is placed in place, operated, and shock waves are repeatedly applied to the crushed carbon black aggregates via methanol. In other words, when the homogenizer is operated in methanol, fine shock waves are continuously generated in the methanol, and the shock waves move through the methanol while exciting the methanol molecules. On the other hand, because methanol has a small molecular weight and low viscosity, the methanol molecules are not easily excited by the shock waves, and the energy of the shock waves is not easily lost. Therefore, fine shock waves are efficiently and repeatedly applied via the methanol to the aggregates immersed in the methanol. As a result, fine shock waves are repeatedly applied to the areas where the aggregates are directly entangled. Because the aggregates are extremely lightweight and the bonding strength between the entangled aggregates is weak, the directly entangled areas are temporarily disentangled, and methanol is adsorbed to the disentangled aggregate areas. Furthermore, shock waves are repeatedly applied, and the aggregates entangled via the methanol are dispersed in the methanol. The aggregates have an irregular, complex structure in which carbon particles are strung together, and the size and shape of each aggregate are different. Therefore, even if the shock waves emitted by the homogenizer device are repeatedly applied to the agglomerates, all of the entangled portions of the aggregates are separated, separating the aggregates into individual aggregates. Furthermore, the separated aggregates cannot be dispersed in methanol. In other words, the separation of entangled aggregates using the homogenizer device is merely a process of adsorbing methanol to the entangled portions of the aggregates and then dispersing the entangled aggregates in methanol. Therefore, in the aggregates in which the aggregates are entangled through methanol, the entangled aggregates are not bonded to each other, and the entangled aggregates are dispersed in methanol. Therefore, in the sixth step, when an alcohol that dissolves or is miscible in methanol is mixed with the second suspension, the aggregates are entangled with each other through the solution in which the alcohol is dissolved in or mixed with methanol, and the aggregates are entangled with each other through the solution in which the alcohol is dissolved in or mixed with methanol. Through the dissolving solution or the mixture A third suspension can be created in which a collection of entangled aggregates is dispersed in the solution or mixture. When an ultrasonic homogenizer is used as the homogenizer, a huge number of bubbles smaller than the size of the cut aggregates are simultaneously generated, and then the bubbles disappear almost simultaneously. This generation and disappearance of bubbles occurs repeatedly according to the ultrasonic generation cycle, and the generation and disappearance of bubbles is repeated in low-viscosity methanol (this phenomenon is called cavitation). Shock waves generated when the bubbles burst are continuously generated in the low-viscosity methanol, and the shock waves are hardly absorbed and are continuously irradiated even to the fine details of the agglomerates, causing the areas where aggregates are directly entangled to separate in a short period of time, and methanol is adsorbed to the separated areas. Therefore, because the ultrasonic homogenizer repeatedly generates and disappears bubbles according to the ultrasonic generation cycle, it is possible to separate the areas where aggregates are directly entangled in a short period of time. In the sixth step, the aggregates are entangled with each other through a solution or a mixture of an alcohol having a viscosity of 3-6 mPa·sec at 20°C dissolved in methanol, and the Through the dissolving solution or the mixture A third suspension is created in which the entangled aggregates are dispersed in a solution or mixture. To achieve this, an alcohol having three properties, namely, a first property of being soluble or miscible in methanol, a second property of having a viscosity 9-20 times that of methanol, and a third property of having a boiling point higher than that of methanol but lower than 200°C, is mixed into the second suspension in the first container at a rate such that the viscosity of the second suspension increases 5-10 times. The aforementioned Alcohol dissolves or is miscible in methanol, The aforementioned The viscosity of the solution or mixture of alcohol and methanol increases to 3-6 mPa·sec at 20°C, and the aggregates become entangled through the solution or mixture. Through the dissolving solution or the mixture A third suspension is prepared in which a collection of entangled aggregates is dispersed in a solution or a mixture. Medium Or a mixture MediumWhen the sheet-like molded article is immersed in the solution, the solution or the mixture is adsorbed onto the surface of the sheet-like molded article to a thickness according to the viscosity of the solution or the mixture. In a seventh step, the sheet-like molded body produced in the first step is The aforementioned Solution Medium Or The aforementioned mixed liquid Medium This allows The aforementioned Dissolving solution or The aforementioned The thickness depends on the viscosity of the mixture. The aforementioned Dissolving solution or The aforementioned The mixed liquid is adsorbed onto the surface of the sheet-like formed body. In the eighth step, the sheet-shaped molded body Surface The whole is covered with a collection of aggregates joined by friction welding. For this purpose, a third container is prepared in which each plate that makes up the four sides of the container, which has a square bottom, has the function of moving parallel to the inside of the container in a direction perpendicular to the side. Next, the first plate created in the second process is placed on top of the multiple protrusions formed on the surface. facing Furthermore, in a seventh step, the third suspension is placed in a third container so that the plurality of grooves through which hydrogen gas passes, which are formed in the sheet-like molded body produced in the first step, overlap with the plurality of protrusions formed in the first plate material. Medium The sheet-like molded body immersed in the solution is placed on the first plate material. Furthermore, the plurality of protrusions formed on the second plate material in the third step are aligned with the plurality of grooves through which oxygen gas or air passes formed on the sheet-like molded body in the first step. and The second plate is then placed on top of the third suspension. Medium Then, the surface of the second plate material is covered with the sheet-shaped molded body immersed in the water. of A compressive load is applied evenly to the entire structure, and the third container is The aforementioned The temperature is raised to the boiling point of the alcohol. Then, the plates constituting the upper and lower side surfaces of the third container are simultaneously moved parallel to the inside of the third container. The plate material The third suspension Medium Sheet-shaped compact immersed in come into contact withThe upper and lower plates are then returned to their original positions. Furthermore, the left and right plates of the third container are simultaneously translated inwardly of the third container. The plate material The third suspension Medium Sheet-shaped compact immersed in come into contact with The surfaces are compressed with a compressive stress equivalent to the compressive load, and then the plates constituting the left and right side surfaces are returned to their original positions. By these treatments, first, methanol and alcohol are evaporated from the third suspension in order according to their boiling points, and the third suspension Medium Sheet-shaped compact immersed in of , a collection of aggregates in which the aggregates are intertwined is Overlapping Next, the sheet-shaped molded body The surface where the first plate and the second plate contact each other and The sheet-like molded body is attached to the top, bottom, left and right sides of the third container. side and the surface in contact with Compressive stress is applied to these in turn, forming a sheet-like compact. The entire surface of The entire collection of entangled aggregates covering the surface is compressed, and the collection of entangled aggregates overlaps each other with a high degree of density. , into a collection of entangled aggregates When compressive stress is applied, the aggregates undergo elastic deformation so as to fill small gaps in the aggregates that are stacked together at a high density, and the aggregates then stack together at an even higher density. , into a collection of entangled aggregates Compressive stress is applied, and all of the aggregates come into contact with each other, and the aggregates are friction-welded at the contact points, forming a group of aggregates that are friction-welded together. Furthermore, compressive stress is applied to the group of friction-welded aggregates, and the group of friction-welded aggregates forms a sheet-like compact. The surface where the first plate and the second plate come into contact and The sheet-like molded body is attached to the top, bottom, left and right sides of the third container. Side and Contacting surfaces The contact area is elastically deformed, and this elastically deformed part of the sheet-like molded body The surface where the first plate and the second plate come into contact and The sheet-like molded body is attached to the top, bottom, left and right sides of the third container. Side and Contacting surfaces with Both The aggregates that penetrate the unevenness of the surface and are friction-welded form a sheet-like compact. The surface where the first plate and the second plate come into contact and The sheet-like molded body is attached to the top, bottom, left and right sides of the third container. Side and Contacting surfacesAs a result, the sheet-shaped molded body Surface The whole is covered with a collection of aggregates joined by friction welding. Joined by friction welding All aggregates In The bonding strength between aggregates in a group of aggregates joined together by friction welding is large. In addition, the group of friction-welded aggregates is The surface where the first plate and the second plate come into contact and The sheet-like molded body is attached to the top, bottom, left and right sides of the third container. Side and Contacting surfaces Furthermore, the aggregates joined by friction welding are thin and lightweight, and are firmly joined to the sheet-shaped compact over a certain area, so even if an impact force is applied to the aggregates joined by friction welding, The impact force on the aggregates is small, The aggregates joined by friction welding are peeled off from the sheet compact. difficulty stomach. In the ninth step, 0.2-0.3G of adhesive is applied to the backside of the bottom of the third container at multiple locations depending on the size of the container. Consists of Identical Size The impact acceleration is applied simultaneously to the first plate and the second plate, and the sheet-like compact, which is sandwiched between the first plate and the second plate and covered with a collection of aggregates bonded to the two plates, is peeled off from the third container. and the second plate material is formed into a sheet-like molded body. Since the bonding strength between the aggregates bonded by friction welding is smaller than that between the aggregates bonded to the two plates, the sheet-like compact covered with the aggregates is pulled out from the bottom of the third container. Priority Furthermore, there are 0.2-0.3G cracks in multiple places on the bottom surface of the first plate. Consists of Identical Size At the same time, an impact acceleration is applied to peel off the sheet-like compact covered with the aggregates from the first plate material. Since the joint between the second plate and the sheet-like molded body is farther from the bottom surface of the first plate than the joint between the first plate and the sheet-like molded body, the impact force applied to the joint between the second plate and the sheet-like molded body is smaller than the impact force applied to the joint between the first plate and the sheet-like molded body, and therefore the joint between the first plate and the sheet-like molded body peels off first. Finally, apply 0.2-0.3G pressure to multiple points on the surface of the second plate. Consists of Identical Size At the same time, an impact acceleration is applied, and the sheet-like compact covered with aggregates is peeled off from the second plate material. By carrying out all of these nine steps consecutively, a fuel cell separator plate is produced, which is made of a sheet-like compact covered with a collection of aggregates joined by friction welding. Next, the effects of the fuel cell separator plate made of the sheet-like molded article will be described. First, in aggregate The entire surface The fuel cell separator plate, made of a sheet-like compact covered with carbon black, has the electrical conductivity of carbon black. In other words, the aggregates, which are friction-welded together, are connected to each other, forming a path for electrons to move through the aggregates. This allows the fuel cell separator plate to have the electrical conductivity of carbon black. As a result, the electrical resistance of the fuel cell separator plate, which is required by the U.S. Department of Energy to be 20 Ω cm or less, is two orders of magnitude lower than the electrical resistance of the separator plate required by the U.S. Department of Energy, due to the electrical resistance of carbon black. Second, the synthetic resin sheet-shaped body is impermeable to hydrogen gas at atmospheric pressure, and therefore the fuel cell separator plate is impermeable to hydrogen gas at atmospheric pressure. Third, Synthetic resin A plurality of grooves through which hydrogen gas passes are formed on one surface of the sheet-like molded body, and a plurality of grooves through which oxygen gas or air passes are formed on the other surface, so that these grooves act as passages for supplying hydrogen gas and oxygen gas or air to the polymer membrane. Fourth, carbon black is not corroded by either acids or alkalis and has better corrosion resistance than metals. Synthetic resin The aggregates covering the sheet-like compact repel all liquids due to the surface tension of the liquid. Synthetic resin Therefore, the particles cannot penetrate into the sheet-shaped compact, which is covered with aggregates. Synthetic resin The separator plate for fuel cells, which is made of a sheet-shaped molded body, has the corrosion resistance of carbon black and is highly resistant to protons (H + ) does not corrode or change over time even in highly oxidizing environments where air passes through. Fifth, Synthetic resin Because the sheet-shaped compact is only 1.5-3 mm thick, it elastically deforms when subjected to an impact, absorbing the force. Furthermore, the aggregates are extremely lightweight, only 3-6 μm thick, and firmly bonded to the sheet-shaped compact, so they do not peel off even when subjected to an impact. Furthermore, if the sheet-shaped compact is made from a synthetic resin with excellent impact resistance, the impact strength of the fuel cell separator plate will be further increased. Sixth, the thickness of the friction-welded aggregates is as thin as 3-6 μm, and the density of the carbon black is 1.7-1.9 g / cm 3 Therefore, the friction-welded aggregate is extremely light. Therefore, the weight of the fuel cell separator plate is Synthetic resin The weight is close to that of the sheet-shaped molded product. On the other hand, the density of synthetic resin is 0.9-1.6g / cm 3 The density of the fiber reinforced resin is 1.5-1.7g / cm 3 The density of aluminum is 2.7 g / cm 3 Smaller. Synthetic resin Because the thickness of the sheet-like molded body is as thin as 1.5-3 mm, the weight of the fuel cell separator plate is significantly lighter than that of conventional fuel cell separator plates. Seventh, sheet-shaped molded articles made of synthetic resins can be molded continuously and inexpensively into molded articles of the same shape. Carbon black is an inexpensive industrial material. Methanol and alcohol are general-purpose organic solvents. Synthetic resin All nine steps involved in producing a separator plate for a fuel cell made of a sheet-like compact are extremely simple. Synthetic resin A separator plate for a fuel cell made of a sheet-like molded body can be produced inexpensively. These seven effects solve all five of the problems described in paragraph 7.

[0010] The method of making a separator plate for a fuel cell according to paragraph 8, The carbon black described in paragraph 8 is acetylene black, and all of the nine steps described in paragraph 8 are continuously performed. The aggregates of the acetylene black are joined by friction welding, and the aggregates are: Made of synthetic resin Sheet-shaped molded body The entire surface of and forming a separator plate for a fuel cell having a structure in which the separator plate is covered with the , a method of making a separator plate for a fuel cell as described in paragraph 8.

[0011] In other words, the characteristics of carbon black vary greatly depending on the manufacturing method, and carbon black is classified by the name of the manufacturing method. The properties of carbon black vary depending on this manufacturing method. Furnace black is carbon black produced by the incomplete combustion of oil or gas in high-temperature gas, and is subdivided into oil furnaces and gas furnaces depending on the raw material being burned. Among furnace blacks, Ketjenblack uses hydrocarbon oil as the raw material, and produces carbon black through the incomplete combustion of the oil. Among carbon blacks, Ketjenblack has the largest specific surface area and DPB (dibutyl phthalate) absorption, and its conductivity is second only to acetylene black. In other words, Ketjenblack has a hollow structure formed by an arc, and electrons move through the arc-shaped structure, increasing the conductivity of Ketjenblack. Other types of carbon black include channel black, which is made by burning natural gas and scraping off the deposits that form on channel steel; acetylene black, which is obtained by thermally decomposing acetylene gas; and thermal black, which is produced by repeatedly burning and decomposing gas in a heat-storing furnace. Acetylene black is produced using acetylene gas, which has the highest purity among the raw materials for carbon black. Therefore, it has the fewest impurities among carbon blacks, and its structure and primary particles are the most developed. Therefore, it has the highest conductivity among carbon blacks. Therefore, when a group of acetylene black aggregates is joined by friction welding, Made of synthetic resinThe fuel cell separator plate, which is constructed by covering a sheet-like molded body, has better conductivity than fuel cell separator plates using other carbon blacks. Also, because the structure and primary particles are most developed, acetylene black aggregates tend to entangle, and once entangled, they are difficult to separate. Therefore, the mechanical strength of the aggregates of acetylene black joined by friction welding is higher than that of fuel cell separator plates using other carbon blacks. Joined by friction welding The mechanical strength of acetylene black is higher than that of a group of aggregates. Therefore, acetylene black is suitable as the carbon black that constitutes the separator plate for the fuel cell described in paragraph 8. For example, acetylene black having a bulk density of 0.04 g / cm 3 There is a powder product with an electrical resistivity of 0.21 Ω·cm. In addition, since all aggregates in the aggregate assembly, which are friction-welded, are connected to each other, a path for electron movement is formed in the aggregate assembly. This gives the fuel cell separator plate the conductivity of acetylene black. As a result, the electrical resistance of the separator plate required by the U.S. Department of Energy is 20 Ω cm or less, but due to the electrical resistance of acetylene black, the electrical resistance of the fuel cell separator plate is two orders of magnitude lower than the electrical resistance required by the U.S. Department of Energy.

[0012] The method for producing a separator plate for a fuel cell described in paragraph 8 comprises: As the synthetic resins mentioned in paragraph 8, A sheet-shaped molded body made of the synthetic resin described in the first step of paragraph 8 is molded using any one of polycarbonate resin, ultra-high molecular weight polyethylene resin, and fiber-reinforced resin, and then all of the treatments described in the second to ninth steps of paragraph 8 are continuously carried out to produce the sheet-shaped molded body made of any one of polycarbonate resin, ultra-high molecular weight polyethylene resin, and fiber-reinforced resin. The entire surface of and creating a separator plate for a fuel cell having a structure in which the separator plate is covered with a collection of aggregates joined by friction welding. As stated in paragraph 8 Method for making a separator plate for a fuel cell。

[0013] That is, among various synthetic resins, polycarbonate resin, ultra-high molecular weight polyethylene resin, and fiber reinforced resin have significantly higher impact strength than other synthetic resins. That is, the Izod impact strength is 93-98kJ / m for polycarbonate resin. 2 , and ultra-high molecular weight polyethylene resin is 98kJ / m 2 , and various fiber-reinforced resins are 100-160kJ / m 2 is. The Izod impact strength of resins other than the above-mentioned synthetic resins is, for example, 2.9-9.8 kJ / m for vinyl chloride resin. 2 and 2.9-7.8kJ / m for polypropylene resin. 2 and 15-49kJ / m for ABS resin. 2 and 1.4-2.2kJ / m for acrylic resin. 2 and polyethylene terephthalate resin, 1.4-3.8kJ / m 2 and 3.9-14kJ / m for nylon 66 resin. 2 and 6.9-12kJ / m for polyacetal resin. 2 and 3.1-7.4kJ / m for polyphenylene sulfide resin. 2 and 14-16kJ / m for polytetrafluoroethylene resin. 2 is. Therefore, polycarbonate resin, ultra-high molecular weight polyethylene resin, or fiber reinforced resin has a significantly higher impact strength than other synthetic resins. Ultra-high molecular weight polyethylene resin is a polyethylene resin whose molecular weight, usually between 20,000 and 300,000, has been increased to between 1,000,000 and 7,000,000. Fiber-reinforced resins are resin materials made by compounding glass fiber, carbon fiber, Zylon fiber, boron fiber, or aramid fiber with polyester resin, epoxy resin, vinylester resin, or phenolic resin, resulting in significantly improved strength, heat resistance, and flame retardancy compared to the base synthetic resin. Strength, heat resistance, and flame retardancy improve depending on the volumetric percentage of fiber. Glass fiber-reinforced plastic (GFRP), made by compounding glass fiber with unsaturated polyester resin, is the least expensive. For example, GFRP containing 30% glass fiber by weight with 25mm glass fiber length increases the impact strength of unsaturated polyester resin by more than 10 times. Therefore, a sheet-shaped molded product made of a synthetic resin as described in the first step of paragraph 8 is formed using polycarbonate resin, ultra-high molecular weight polyethylene resin, or fiber-reinforced resin, and then all of the processes in the second to ninth steps of paragraph 8 are continuously carried out to produce a sheet-shaped molded product made of polycarbonate resin, ultra-high molecular weight polyethylene resin, or fiber-reinforced resin. The entire surface of However, a separator plate for a fuel cell is produced, which is made up of a structure covered with a collection of aggregates joined by friction welding. Made of synthetic resin Although the sheet-shaped molded body is thin, at only 1.5-3 mm, the separator plate for fuel cells has high impact strength.

[0014] The method of making a separator plate for a fuel cell according to paragraph 8, The alcohol having the three properties described in paragraph 8 is any one of 2-methyl-1-butanol, 3-pentanol, 1-octanol, isooctanol, 2-ethyl-1-hexanol, 1-hexanol, 1-heptanol, and 2-ethyl-1-hexanol, Either One type of alcohol is used as an alcohol having the three properties described in paragraph 8, and all of the nine processes described in paragraph 8 are carried out consecutively, and the aggregates joined by friction welding are: Made of synthetic resin Sheet-shaped molded body The entire surface of and a method for producing a separator plate for a fuel cell, the separator plate having a structure in which the separator plate is covered with the 。

[0015] In other words, there are alcohols that have the three properties described in paragraph 8: the first property of being soluble or miscible in methanol, the second property of having a viscosity 9-20 times that of methanol, and the third property of having a boiling point higher than that of methanol but lower than 200°C. These alcohols include 2-methyl-1-butanol, 3-pentanol, 1-octanol, isooctanol, 2-ethyl-1-hexanol, 1-hexanol, 1-heptanol, and 2-ethyl-1-hexanol. 2-Methyl-1-butanol CH3CH2CH(CH3)CH2OH is miscible with methanol, has a viscosity of 5.1 mPa·s at 25°C, which is 9.4 times the viscosity of methanol at 25°C, and has a boiling point of 128°C, making it an alcohol that possesses all three of the properties described in paragraph 8. 3-Pentanol CH3CH2CHOHCH2CH3 dissolves in methanol, has a viscosity of 6.7 mPa·s at 20°C, which is 11.4 times the viscosity of methanol at 20°C, and has a boiling point of 116°C, making it an alcohol that possesses all three of the properties described in paragraph 8. 1-Octanol CH3(CH2)6CH2OH is miscible with methanol, has a viscosity of 7.3 mPa·s at 25°C, which is 13.5 times the viscosity of methanol at 25°C, and has a boiling point of 195°C, making it an alcohol that possesses all three of the properties described in paragraph 8. Isooctanol CH3(CH2)3CH2CH2CH3CH2OH dissolves in methanol, has a viscosity of 12.0 mPa·s at 20°C, which is 20.3 times the viscosity of methanol at 20°C, and has a boiling point of 188°C, making it an alcohol that possesses all three of the properties described in paragraph 8. 2-Ethyl 1-hexanol CH3(CH2)3CH(CH2CH3)CH2OH is soluble in methanol, has a viscosity of 10.0 mPa·s at 20°C, which is 16.9 times the viscosity of methanol at 20°C, and has a boiling point of 182°C, making it an alcohol that possesses all three of the properties described in paragraph 8. 1-Hexanol CH3(CH2)3OH dissolves in methanol, has a viscosity of 5.2 mPa·s at 20°C, which is 8.8 times the viscosity of methanol at 20°C, and has a boiling point of 157°C. It is an alcohol that combines the three properties described in paragraph 8. 1-Heptanol CH3(CH2)5CH2OH dissolves in methanol, has a viscosity of 5.8 mPa·s at 25°C, which is 10.7 times the viscosity of methanol at 25°C, and has a boiling point of 176°C. It is an alcohol that possesses all three of the properties described in paragraph 8. 2-Ethyl-1-hexanol CH3(CH2)3CH(C2H5)CH2OH is soluble in methanol, has a viscosity of 9.8 mPa·s at 20°C, which is 16.6 times the viscosity of methanol at 20°C, and has a boiling point of 185°C, making it an alcohol that possesses all three of the properties described in paragraph 8. Therefore, if any one of these alcohols is used as an alcohol having the three properties described in paragraph 8 and all of the nine steps described in paragraph 8 are performed consecutively, the aggregates joined by friction welding will be Made of synthetic resin Sheet-shaped molded body The entire surface of A separator plate for a fuel cell is produced, which has a structure in which the above is covered. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 is a schematic diagram showing a cross section of a sample in which the entire surface of a sheet-like molded product made of polycarbonate resin is covered with a collection of acetylene black aggregates joined by friction welding. DETAILED DESCRIPTION OF THE INVENTION

[0017] Example 1 In this example, polycarbonate resin pellets (Panlite, Teijin Limited) were used to extrude a sheet-like molded body measuring 30 cm x 30 cm x 2 mm (thickness). On one surface of the molded body, multiple grooves measuring 30 cm (length) x 5 mm (width) x 1 mm (depth) were formed at regular intervals to allow hydrogen gas to pass through, and on the other surface of the molded body, multiple grooves measuring 30 cm (length) x 5 mm (width) x 1 mm (depth) were formed at the same intervals as above in areas where the grooves were not formed to allow oxygen gas or air to pass through. The Charpy impact strength of Panlite with a notch was 76 kJ / m 2 and big. On the other hand, the synthetic resin material that constitutes the sheet-shaped molded body is not limited to polycarbonate resin. As described in paragraph 13, polycarbonate resin is a type of synthetic resin that has excellent impact resistance. Therefore, polycarbonate resin is effective in producing a separator plate for a fuel cell that has excellent impact resistance. To further improve impact resistance, a resin containing glass fiber can be used. On the other hand, if impact resistance is not required for the separator plate for a fuel cell, As stated in paragraph 13 Sheet-shaped moldings are made from synthetic resins made from various materials. In addition, the shape of the grooves formed on the surface of the sheet-like molded body is not limited to the elongated rectangle described above. Since the grooves are formed by molding synthetic resin, the shape of the grooves is not limited. Furthermore, when grooves are formed by machining, the cost of forming the grooves varies greatly depending on the shape and number of the grooves. However, when grooves are formed by molding synthetic resin, the cost of forming the grooves varies greatly depending on the shape and number of the grooves. For molding The cost of the mold changes, but the cost of forming the groove remains the same.

[0018] Example 2 In this example, a sheet-like molded body having dimensions of 30 cm x 30 cm x 4 mm (thickness) was molded by extrusion molding using the polycarbonate resin pellets of Example 1. Note that the plurality of grooves through which hydrogen gas passes formed in the sheet-like molded body of Example 1 was formed The plurality of grooves are and A plurality of overlapping projections were formed. The material of the sheet-shaped molding is not limited to polycarbonate resin.

[0019] Example 3 In this example, a sheet-like molded body having a size of 30 cm x 30 cm x 4 mm (thickness) was molded by extrusion molding using the polycarbonate resin pellets of Example 1. Note that the plurality of grooves formed in the sheet-like molded body of Example 1 through which oxygen gas or air passes was formed The plurality of grooves are and A plurality of overlapping projections were formed. The material of the sheet-shaped molding is not limited to polycarbonate resin.

[0020] Example 4 In this example, acetylene black is used as carbon black, and the acetylene black is crushed to a minimum size in methanol, and the crushed acetylene black is dispersed in methanol to prepare a suspension. First, 40 g of acetylene black (Li-100, a product of Denka Co., Ltd.) and 80 g of industrial grade 1 methanol were filled into a container, and the methanol was stirred to immerse the acetylene black in the methanol. First order of grain child The diameter is 35 nm and the specific surface area is 68 m 2 / g and is composed of primary particles with an iodine adsorption capacity of 92 mg / g. Acetylene black has a bulk density of 0.04 g / ml and an electrical resistivity of 0.21 Ω·cm, making it the most conductive of all carbon blacks. After this, a flat plate was placed on top of the container, and nine 2 kg weights were placed on the plate at equal intervals. The weights and plate were then removed, and the container was fixed on a vibration table. A vibration acceleration of 2 G was repeatedly applied to the container in three directions: front-back, left-right, and up-down. After repeating this pair of treatments of applying a compressive load and applying a vibration acceleration five times, the weight was placed on the plate. However, since there was no movement of the plate, it was determined that the acetylene black had been crushed to the limit size in methanol, and the pair of treatments was stopped. Furthermore, an ultrasonic homogenizer (LUH150, product of Yamato Scientific Co., Ltd.) was operated in the methanol in the container, and a 20 kHz ultrasonic signal was applied for 15 minutes, creating a suspension in which aggregates entangled with each other were dispersed in methanol.

[0021] Example 5 In this example, the suspension prepared in Example 4 was mixed with 3-pentanol described in paragraph 15 to increase the viscosity of the suspension to 6.8 times the viscosity of methanol, and the solution in which 3-pentanol was dissolved in methanol was via dissolution A new suspension is prepared in which the entangled aggregates are dispersed. Furthermore, the sheet-like compact prepared in Example 1 is added to the new suspension. Medium The sheet-shaped molded body is immersed in a solution of 3-pentanol dissolved in methanol, and the solution is applied to the sheet-shaped molded body. For this purpose, 101 g of 3-pentanol was mixed with the suspension prepared in Example 4, and the resulting solution of 3-pentanol dissolved in methanol was via dissolution A new suspension was prepared in which the entangled aggregates were dispersed. After this, the sheet-like compact prepared in Example 1 was added to the new suspension. Medium The sheet-like molded product was immersed in a solution of 3-pentanol dissolved in methanol, and the sheet-like molded product was taken out. Note that the alcohol that increases the viscosity of the suspension to 5-10 times that of methanol is not limited to 3-pentanol. By using various types of alcohols described in paragraph 15 and changing the mixing ratio of the alcohol to the suspension depending on the viscosity of the alcohol, a solution or mixture of alcohol with a viscosity of 3-6 mPa·sec at 20°C described in paragraph 8 in methanol can be obtained.

[0022] Example 6 In this example, the aggregates adsorbed on the sheet-like compact prepared in Example 1 are friction-welded, and the friction-welded aggregates are then applied to the surface of the sheet-like compact. The whole of The sheet-shaped molded body is friction-welded to the SurfaceThe whole is covered with a collection of aggregates joined by friction welding. First, a container was prepared, measuring 35 cm x 35 cm, 2 cm deep, and 2 cm wide, with four side plates that could be moved parallel to the inside of the container in a direction perpendicular to the side. Next, the sheet-like molded product prepared in Example 2 was placed 1 cm away from the four side surfaces of the container, with the multiple protrusions facing upward. Next, the new suspension prepared in Example 5 was applied to the plurality of protrusions of the sheet-like molded body prepared in Example 2. Medium The sheet-shaped molded body was immersed in the new suspension so that the multiple grooves through which hydrogen gas passes overlapped. Medium The sheet-like molded article was then covered with the solution. Furthermore, the multiple protrusions of the sheet-like molded body prepared in Example 3 were Medium A plurality of grooves through which oxygen gas or air passes in a sheet-like molded body immersed in water. and The sheet-like molded body prepared in Example 3 was placed on top of the new suspension Medium The sheet-shaped molded body was covered with the solution. Thereafter, nine 2 kg weights were placed at equal intervals on the surface of the sheet-like molded product prepared in Example 3. Furthermore, the container was heated to 116° C., which is the boiling point of 3-pentanol. Furthermore, the plates constituting the upper and lower side surfaces of the container are simultaneously moved in parallel to the inside of the container, The plate material The new suspension Medium Sheet-shaped compact immersed in come into contact with The upper and lower plates were then compressed with a compressive stress equivalent to the compressive load applied to the sheet-like molded body prepared in Example 3, and the plates constituting the upper and lower side surfaces were then returned to their original positions. Furthermore, the plates constituting the left and right side surfaces of the container were simultaneously moved in parallel toward the inside of the container, The plate material The new suspension Medium Sheet-shaped compact immersed in come into contact with The left and right side surfaces were compressed with a compressive stress equivalent to the compressive load applied to the sheet-like molded body prepared in Example 3, and then the plates constituting the left and right side surfaces were returned to their original positions. After this, 0.3G was applied to nine equally spaced points on the bottom of the container. consisting of the same size The new suspension is sandwiched between two sheet-like compacts and bonded to the two compacts by applying impact acceleration simultaneously. Medium The sheet-like molded body immersed in the solution was peeled off from the container. consisting of the same size A new suspension that bonds two compacts by applying impact acceleration simultaneously Medium The sheet-like molded body immersed in the solution was peeled off from the sheet-like molded body prepared in Example 2. Finally, 0.3 G consisting of the same size At the same time, impact acceleration is applied and a new suspension Medium The sheet-like compact immersed in the solution was peeled off from the sheet-like compact produced in Example 3, to obtain a sheet-like compact covered with a collection of aggregates. The surface of the sheet-like compact covered with aggregates was observed using an electron microscope. An ultra-low accelerating voltage SEM owned by JFE Techno-Research Corporation was used as the electron microscope. This device is capable of surface observation at ultra-low accelerating voltages starting from 100V, allowing the sample surface to be observed directly without forming a conductive coating. First, secondary electron beams between 900-1000 volts were extracted from the electron beam reflected from the surface and image processing was performed. Fine black material was stacked with no gaps, with a high degree of integration. Next, energies between 900-1000 volts were extracted from the electron beam reflected from the surface and image processing was performed, and the material of the black material was analyzed based on the shade of the image. As no shade was observed, it was determined that it was composed of a single atom. Furthermore, the energy and intensity of characteristic X-rays from the surface were image processed and the type of elements that made up the black material were analyzed. The black material was composed only of carbon atoms. From the above observation results, it was found that acetylene black aggregates were stacked with a high degree of accumulation over the entire surface of the sheet-like molded body. Next, the surface resistance of the sheet-like compact covered with aggregates was measured at multiple points using a surface resistance meter (e.g., a surface resistance meter ST-4 from Simco Japan Co., Ltd.). The surface resistivity was 1.0 Ω, which means that the compact had a resistance close to the resistivity of acetylene black, 0.21 Ω cm. Furthermore, the hydrogen gas permeability of the sheet-shaped molded body covered with a collection of aggregates was measured using a gas permeability measuring device using differential pressure gas chromatography, and it was found that hydrogen gas did not permeate at atmospheric pressure. Furthermore, a sheet-like compact covered with aggregates was allowed to drop from a height of 2 m without being damaged, demonstrating that it has a certain level of mechanical strength even with a thickness of 2 mm. Note that the mechanical strength of the sheet-like compact can be further increased by molding it with a fiber-reinforced resin with even greater impact resistance as described in paragraph 13. Finally, a portion of the sheet-like molded product covered with aggregate aggregates was cut, and the cut surface was observed using the electron microscope described above. It was found that aggregate aggregates of acetylene black covered the surface of the sheet-like molded product to a thickness of 4 μm. Figure 1 shows an enlarged schematic of the cut surface. 1 is the aggregate aggregates of laminated acetylene black, and 2 is the molded product made of polycarbonate resin. [Explanation of symbols]

[0023] 1. Acetylene black aggregate collection 2. Molded body made of polycarbonate resin

Claims

1. A method for producing a separator plate for a fuel cell, which has a structure in which the entire surface of a sheet-like molded body made of synthetic resin is covered with a collection of carbon black aggregates bonded by friction welding, comprises the steps of: a first step of molding a sheet-like molded body made of synthetic resin, the sheet-like molded body having a plurality of grooves formed on one surface through which hydrogen gas passes and a plurality of grooves formed on the other surface through which oxygen gas or air passes; a second step of molding a first plate material made of synthetic resin, the first plate material having the same size as the sheet-like molded body, a thickness greater than that of the sheet-like molded body, and having a plurality of protrusions formed at positions where a plurality of grooves through which hydrogen gas passes are formed in the sheet-like molded body, the protrusions having shapes that overlap the plurality of grooves; a third step of molding a second plate material made of synthetic resin, the second plate material having the same size as the sheet-like molded body, a thickness greater than that of the sheet-like molded body, and having a plurality of protrusions formed at positions where a plurality of grooves through which oxygen gas or air passes are formed in the sheet-like molded body, the protrusions having shapes that overlap the plurality of grooves; Carbon black clumps and methanol having a weight greater than the weight of the carbon black clumps are placed in a first container, the methanol is stirred, and a first suspension is prepared in which the carbon black clumps are immersed in the methanol. Thereafter, a third plate material that covers the entire surface of the first suspension is placed on top of the first suspension, and a compressive load is applied evenly to the entire surface of the third plate material to crush the carbon black clumps immersed in the methanol. The first container is then placed on a vibration table of a vibrator, and the vibrator is operated to repeatedly apply vibration accelerations in three directions, front-to-back, left-to-right, and up-to-down, to the first container to rearrange the crushed carbon black clumps in the methanol. Thereafter, the compressive load is again applied evenly to the entire surface of the third plate material to crush the carbon black clumps. further crushing the carbon black clumps in the methanol; and repeatedly applying the vibration acceleration in the three directions to the first container again. This pair of processes consisting of the process of applying the compressive load and the process of applying the vibration acceleration is repeated, and if the carbon black has been crushed to a critical size when the compressive load is applied to the third plate, even if the crushed carbon black is compressed, no compressive stress is applied to the fine carbon black, so the fine carbon black is not crushed and a repulsive force is generated in the third plate. When a repulsive force is generated in the third plate, it is determined that the crushing of the carbon black clumps in the methanol is complete and the pair of processes is stopped. Thereafter, a fourth process of removing the third plate from the first container. a fifth step of disposing an ultrasonic homogenizer in the first container, operating the homogenizer in the first suspension, and repeatedly applying shock waves to the aggregates of the crushed carbon black via the methanol, thereby entangling aggregates in the crushed carbon black via the methanol, and preparing a second suspension in which the aggregates entangled via the methanol are dispersed in the methanol; a sixth step of mixing an alcohol having three properties, namely, a first property of being soluble or miscible in methanol, a second property of having a viscosity 9 to 20 times that of methanol, and a third property of having a boiling point higher than that of methanol but lower than 200°C, with the second suspension, increasing the viscosity of a solution in which the alcohol is dissolved in the methanol or a mixture in which the alcohol is mixed to 3 to 6 mPa sec at 20°C, entangling the aggregate groups entangled via the methanol via the solution or mixture, and preparing a third suspension in which the aggregate groups entangled via the solution or mixture are dispersed in the solution or mixture; a seventh step of pouring the third suspension into a second container having a bottom surface slightly larger than the sheet-like compact produced in the first step, and further immersing the sheet-like compact in the third suspension; The first plate material prepared in the second step is placed in a third container in which each plate material constituting the four side surfaces of the container has the function of moving parallel to the inside of the container in a direction perpendicular to the side surface, with the plurality of protrusions formed on the first plate material facing upward; further, the sheet-like molded body immersed in the third suspension is placed on the first plate material so that the plurality of grooves formed on the sheet-like molded body through which hydrogen gas passes overlap the plurality of protrusions formed on the first plate material; and further, the plurality of protrusions formed on the second plate material prepared in the third step are placed on the sheet-like molded body so that the plurality of protrusions formed on the first plate material overlap the plurality of grooves through which hydrogen gas passes. The second plate is placed on the sheet-like formed body immersed in the third suspension so that the grooves formed on the sheet-like formed body through which oxygen gas or air passes overlap with each other. Thereafter, a compressive load is applied evenly to the entire surface of the second plate, and the temperature of the third container is raised to the boiling point of the alcohol. Furthermore, the plate members constituting the upper and lower side surfaces of the third container are simultaneously translated inward of the third container, and the surfaces of the plate members that come into contact with the sheet-like formed body immersed in the third suspension are brought into contact with the compressive load. The plate members constituting the left and right side surfaces of the third container are simultaneously moved parallel to the inside of the third container, and the surfaces of the plate members that come into contact with the sheet-like molded body immersed in the third suspension are compressed with a compressive stress corresponding to the compressive load, and then the plate members constituting the left and right side surfaces are returned to their original positions. As a result, the methanol and the alcohol are evaporated from the third suspension, and the surface of the sheet-like molded body immersed in the third suspension is compressed with a compressive stress corresponding to the compressive load, and then the plate members constituting the left and right side surfaces are returned to their original positions. an eighth step in which the entire surface of the sheet-like compact is covered with a group of entangled aggregates, a compressive stress is applied to the entire surface of the sheet-like compact, the entangled aggregates covering the entire surface of the sheet-like compact are friction-welded to each other, and the compressive stress is applied to the friction-welded aggregate groups, the friction-welded aggregate groups are friction-welded to the entire surface of the sheet-like compact, and the entire surface of the sheet-like compact is covered with the group of aggregates joined by friction welding; a ninth step of simultaneously applying impact accelerations of the same magnitude to a plurality of locations on the bottom surface of the third container, thereby peeling off from the third container a sheet-like compact covered with the aggregate collection that is sandwiched between and joined to both the first plate and the second plate; further simultaneously applying impact accelerations of the same magnitude and magnitude as those applied above to a plurality of locations on the bottom surface of the first plate, thereby peeling off the sheet-like compact covered with the aggregate collection from the first plate; and finally simultaneously applying impact accelerations of the same magnitude and magnitude as those applied above to a plurality of locations on the surface of the second plate, thereby peeling off the sheet-like compact covered with the aggregate collection from the second plate; By continuously carrying out all of these nine steps, a method for producing a separator plate for a fuel cell is produced, in which the entire surface of a sheet-like molded body made of synthetic resin is covered with a collection of carbon black aggregates bonded by friction welding.

2. The method for producing a separator plate for a fuel cell according to claim 1 comprises the steps of:

10. A method for producing a fuel cell separator plate as defined in claim 1, comprising the steps of: using acetylene black as the carbon black as defined in claim 1; continuously carrying out all nine steps as defined in claim 1; and producing a fuel cell separator plate having a configuration in which a group of acetylene black aggregates are joined by friction welding and the group of aggregates covers the entire surface of a sheet-like molded body.

3. The method for producing a separator plate for a fuel cell according to claim 1 comprises the steps of: A method for producing a separator plate for a fuel cell as defined in claim 1, comprising: forming a sheet-like molded body from the synthetic resin as defined in the first step of claim 1 using one type of synthetic resin selected from the group consisting of polycarbonate resin, ultra-high molecular weight polyethylene resin, and fiber-reinforced resin; and continuously carrying out all of the treatments as defined in the second to ninth steps of claim 1 to produce a separator plate for a fuel cell having a configuration in which the entire surface of the sheet-like molded body from one type of synthetic resin selected from the group consisting of polycarbonate resin, ultra-high molecular weight polyethylene resin, and fiber-reinforced resin is covered with a collection of aggregates joined by friction welding.

4. The method for producing a separator plate for a fuel cell according to claim 1 comprises the steps of: A method for producing a fuel cell separator plate as defined in claim 1, wherein the alcohol having the three properties defined in claim 1 is any one of 2-methyl-1-butanol, 3-pentanol, 1-octanol, isooctanol, 2-ethyl-1-hexanol, 1-hexanol, 1-heptanol, and 2-ethyl-1-hexanol, and the method uses the any one of the alcohols having the three properties defined in claim 1, and continuously performs all of the nine steps defined in claim 1 to produce a fuel cell separator plate having a configuration in which a collection of aggregates joined by friction welding covers the entire surface of a sheet-like molded body.

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