JP5196219B2 - Method for confirming cell stack misalignment of fuel cell and gauge for confirming cell stack misalignment of fuel cell - Google Patents

Description

  The present invention relates to a cell stack misalignment confirmation method for fuel cells and a cell stack misalignment confirmation gauge for fuel cells.

  A solid polymer electrolyte fuel cell is configured by laminating cells including a membrane-electrode assembly (MEA) and a separator. A terminal (electrode plate), an insulator, and an end plate are arranged at both ends of the cell stack in the cell stacking direction, the cell stack is clamped in the cell stacking direction, and a fastening member extending in the cell stacking direction outside the cell stack (for example, A so-called cell stack is formed by fixing with a tension plate) and bolts.

Since cell stacking accuracy is low (deviation occurs in the surface direction of the separator), the contact resistance is affected, so it is important to perform management. Conventionally, a cell gap is detected or confirmed by measuring a step between adjacent cells with a dial gauge from the outside or by detecting the presence or absence of contact with a cell outer peripheral end face (for example, Patent Documents 1 to 5). reference).
JP 2006-172814 A JP-A-9-134734 JP 2002-56882 A Japanese Utility Model Publication No. 60-192372 JP 2001-57226 A

However, as the number of stacked cells increases, the number of measurements also increases. For example, when the number of cells is 400, 400 points need to be measured. Further, it is necessary to measure and calculate the deviation at least twice in the X direction and the Y direction. For this reason, it is difficult to confirm all the misalignment between adjacent cells, and only representative points may be measured by sampling.
Furthermore, in recent years, thin cell thicknesses such as metal press separators have been developed, and measurement has become increasingly difficult.

  In view of the above circumstances, the present invention provides a cell stack misalignment confirmation method and a fuel cell stack misalignment confirmation gauge capable of easily confirming the stack state of a cell in which a large number of cells are stacked. Objective.

  In order to achieve the above object, the present invention provides a method for confirming stacking misalignment of cells constituting a cell stack, by inserting a gauge of a predetermined size into a pin hole provided in the cell. This is to detect stacking misalignment.

  If there is no deviation in the laminated state, a gauge can be inserted. When there is a stacking error, the pin hole wall part interferes to prevent the gauge from being inserted. This makes it possible to confirm that there is a stacking shift. In addition, it is possible to easily confirm the stacked state of the cells in which a large number of sheets (for example, 200 to 400 sheets) are stacked using a gauge.

  The diameter of the portion of the gauge having the largest diameter can be (the hole diameter of the pin hole−the deviation tolerance). Thereby, by inserting a gauge, it is possible to detect a stacking deviation larger than the deviation tolerance.

  The gauge has a large-diameter portion whose diameter dimension is (the hole diameter of the pin hole—a deviation tolerance), and extends in an axial direction from at least one end of the large-diameter portion, and has a diameter dimension of (the hole diameter of the pin hole−straight). It is also possible to detect the straightness of the cell at the same time as the stacking misalignment of the cell by inserting the gauge into the pin hole. Thereby, stacking | deviation and straightness can be measured simultaneously by inserting a gauge. Further, by setting the portion where the diameter of the gauge is (the hole diameter of the pin hole−the deviation tolerance) to have a length corresponding to three cells in the gauge axis direction, one cell and its cell Only the displacement between the upper and lower cells is detected, and only the “lamination misalignment” excluding the straightness component (waviness etc.) can be measured.

  Further, the cell stack misalignment confirmation gauge of the present invention is a gauge for confirming the stack misalignment of the cells constituting the cell stack, and the diameter dimension of the portion having the largest diameter is (the pin provided in the cell). The diameter of the hole is equal to the deviation tolerance), and the displacement of the cell is detected by being inserted into the pin hole.

  When the gauge configured as described above is inserted into the pin hole of the cell, if there is a stacking error, the pin hole wall part interferes to prevent the gauge from being inserted. As a result, it is possible to detect the misalignment.

  The gauge has a large-diameter portion whose diameter is (a hole diameter of a pin hole provided in the cell—a deviation tolerance), and extends in an axial direction from at least one end of the large-diameter portion. -A thin diameter portion having a diameter of (straightness tolerance). Thereby, stacking | deviation and straightness can be measured simultaneously by inserting a gauge.

  According to the present invention, by inserting a gauge into a pin hole provided in a cell, it is possible to easily confirm the stacked state of a cell in which a large number of layers are stacked.

  Hereinafter, the configuration of the present invention will be described in detail based on an example of an embodiment shown in the drawings.

  1 to 6 show an embodiment of a fuel cell cell stack misalignment confirmation method and a fuel cell stack misalignment confirmation gauge. In the embodiments described below, the overall configuration of the fuel cell 1 will be described first, followed by a cell stacking displacement confirmation gauge and a confirmation method.

  1 and 2 show a schematic configuration of a fuel cell 1 according to the present embodiment. The fuel cell 1 shown in the present embodiment can be used as, for example, an in-vehicle power generation system of a fuel cell vehicle (FCHV; Fuel Cell Hybrid Vehicle), but is not particularly limited to this, and various mobile objects (for example, ships and It can also be used in power generation systems mounted on self-propelled devices such as airplanes) and robots, and even stationary power generation systems.

  The fuel cell 1 includes a cell stack (cell stack) 3 in which a plurality of cells (power generation cells) 2 are stacked, and the outer side in the stacking direction of the end cells 2 positioned at both ends of the cell stack 3. The configuration further includes a terminal plate 5 with an output terminal 5 a, an insulator (insulating plate) 6, and an end plate 7. A predetermined compressive force in the stacking direction is applied to the cell stack 3 by a tension plate 8 that is bridged so as to connect both end plates 7. Further, a pressure plate 9 and a spring mechanism 9a are provided between the end plate 7 on one end side of the cell stack 3 and the insulator 6, so that the fluctuation of the load acting on the cell 2 is absorbed. ing.

  The cell 2 includes an electrolyte membrane composed of an ion exchange membrane and a membrane-electrode assembly (MEA) composed of a pair of electrodes sandwiching the electrolyte membrane from both sides, and a pair of separators sandwiching the membrane-electrode assembly from the outside. , Is composed of. The separator is, for example, a conductor based on metal, has a fluid flow path for supplying an oxidizing gas such as air and a fuel gas such as hydrogen gas to each electrode, and is supplied to the cells 2 adjacent to each other. It serves to block the mixing of different fluids. With this configuration, an electrochemical reaction occurs in the membrane-electrode assembly of the cell 2 and an electromotive force is obtained. Since this electrochemical reaction is an exothermic reaction, the separator is provided with a fluid flow path for flowing a coolant (for example, cooling water) for cooling the fuel cell.

  Furthermore, manifolds (an oxidizing gas manifold, a fuel gas manifold, a refrigerant manifold) for flowing the oxidizing gas, the fuel gas, and the refrigerant in the cell stacking direction are formed, for example, near both ends of the separator. In the fuel cell 1 of the present embodiment, each fluid (oxidizing gas, fuel gas, refrigerant) is supplied from the fluid supply pipe (not shown) provided on the end plate 7 at one end of the fuel cell 1 to the inlet side. Are supplied to the manifolds and flow through the fluid flow paths provided in the separators of the cells 2. Further, each fluid is discharged from each manifold on the outlet side to each fluid discharge pipe (not shown) provided on the end plate 7 at the other end of the fuel cell 1.

  The heat insulation cell 4 has a heat insulation layer formed of, for example, two separators and a seal member, and plays a role of suppressing heat generated by power generation to be radiated to the atmosphere. That is, in general, the temperature of the end portion of the cell stack 3 is likely to be lowered by heat exchange with the atmosphere, and thus heat exchange (heat dissipation) is suppressed by forming a heat insulating layer at the end of the cell stack 3. Has been done. As such a heat insulating layer, for example, there is a structure in which a heat insulating member 10 such as a conductive plate is sandwiched between a pair of separators similar to those in the cell 2 instead of the membrane-electrode assembly. The heat insulating member 10 used in this case is more suitable as it has better heat insulating properties. Specifically, for example, a conductive porous sheet or the like is used. Moreover, an air layer is formed by sealing the circumference | surroundings of such a heat insulation member 10 with a sealing member. Furthermore, the manifold of each fluid is sealed with a sealing member around it and separated from the heat insulating layer.

  The terminal plate 5 is a member that functions as a current collecting plate, and is formed in a plate shape from a metal such as iron, stainless steel, copper, or aluminum. The surface of the terminal plate 5 on the heat insulating cell 4 side is subjected to a surface treatment such as a plating treatment, and the contact resistance with the heat insulating cell 4 is ensured by the surface treatment. Examples of the plating include gold, silver, aluminum, nickel, zinc, tin, and the like. For example, in this embodiment, tin plating is performed in consideration of conductivity, workability, and low cost.

  The insulator 6 is a member that functions to electrically insulate the terminal plate 5 from the end plate 7 and the like. In order to fulfill such a function, the insulator 6 is formed in a plate shape from a resin material such as polycarbonate.

  The end plate 7 is formed in a plate shape with various metals (iron, stainless steel, copper, aluminum, etc.) like the terminal plate 5. For example, in the present embodiment, the end plate 7 is formed using copper, but this is merely an example, and the end plate 7 may be formed of another metal.

  The cell stack 3 is constrained in a stacked state by a tension plate 8 as a constraining member. The tension plate 8 is provided so as to bridge between the end plates 7 and 7 and is disposed so that, for example, a pair is opposed to both sides of the cell stack 3 (see FIG. 1). The tension plate 8 is fixed to the end plates 7 and 7 with bolts or the like, and maintains a state in which a predetermined fastening force (compression force) is applied in the stacking direction of the single cells 2. An insulating film is formed on the inner surface of the tension plate 8 (the surface facing the cell stack 3) in order to prevent leakage or sparks. Specifically, the insulating film is formed by, for example, an insulating tape attached to the inner surface of the tension plate 8 or a resin coating applied so as to cover the surface.

  Each cell 2 and end plate 8 of the cell stack 3 are formed with pin holes 40 penetrating in the thickness direction at predetermined positions on both sides in the longitudinal direction (FIG. 2). These pin holes 40 are formed at the same position so as to overlap each other and penetrate the entire cell stack 3 in a straight line when the cells 2 are stacked at the correct positions. The number of pin holes 40 is two in the present embodiment, but may be increased or decreased as necessary.

  FIG. 3 shows a gauge 50 that can be used in the method for checking the stacking deviation of the cell stack 3 according to this embodiment. The gauge 50 includes a small-diameter portion 51 having a sufficiently long length, and a large-diameter portion 52 provided at one end of the small-diameter portion 51 and having a length of about the thickness of three stacked cells 2. The diameter of the large diameter portion 52 is a size corresponding to a difference obtained by subtracting the deviation tolerance from the hole diameter of the pin hole 40 (hole diameter of the pin hole 40 minus deviation tolerance). For example, when the hole diameter is 10 mm (φ10 mm) and the allowable stacking deviation is 0.3 mm, the outer diameter of the large diameter portion 52 is (10−0.3 =) 9.7 mm. The small-diameter portion 51 is sufficiently thinner than the large-diameter portion 52 so that the gauge 50 can be smoothly inserted into the pin hole 40.

In the cell stacking deviation confirmation method of the present embodiment, the large diameter portion 52 is inserted into the pin hole 40 using such a gauge 50. When the stacking misalignment of the cells 2 is large, the large diameter portion 52 cannot pass through the pin hole 40 at that portion, so that the stacking misalignment of each cell 2 is within a tolerance (0.3 mm in this example). It can be checked by checking whether it exists. Since the displacement in the X-axis direction and the Y-axis direction can be measured simultaneously only by inserting the gauge 50, the inspection becomes easier as compared with the conventional case. Further, there is an advantage that the stacking deviation can be inspected for all the cells 2 instead of the sampling inspection performed only for the arbitrary cells 2. Furthermore, various types of cell stacks 3 can be measured by preparing various gauges 50 having a large diameter portion 52 corresponding to the cell thickness in advance and using the gauges 50 depending on the measurement target.
Further, in the case of the present embodiment in which the length of the large diameter portion 52 is equivalent to the thickness of about three cells 2, only “lamination misalignment” excluding straightness components (swells and the like) can be measured. If the diameter of the entire gauge is (the hole diameter of the pin hole 40-the deviation tolerance), the gauge will not pass if there is a undulation even if the lamination deviation is within the standard. In the present embodiment, since the large-diameter portion 52 detects a shift of three cells 2, the inspection can be performed except for the straightness component.

  Thus, according to the cell stacking deviation confirmation method of the cell stack 3 of this embodiment and the gauge that can be used for the checking method, the stacking deviation of the cell 2 can be easily inspected and confirmed. The productivity of the body 3 can be improved.

As a modification, the following gauge may be adopted.
The gauge 60 shown in FIG. 4 has a uniform diameter in the entire longitudinal direction (hole diameter of the pin hole 40-deviation tolerance). With this gauge 60, the entire longitudinal direction of the cell stack 3 is penetrated. Thereby, the stacking deviation of the cell 2 can be detected. However, if the laminate has undulations, the gauge cannot pass through the actual stacking deviation amount, resulting in excessive quality. Therefore, when inspecting except for the straightness component, the gauge 50 described above or the modification shown below is used. It is preferable to use the gauge.

Like the gauge 65 shown in FIG. 5, a gauge moving string 67 may be provided above and below a pin gauge 66 having a diameter of (the hole diameter of the pin hole−deviation tolerance).
Further, like the gauge 70 shown in FIG. 6, the small diameter portion 72 may extend from the upper and lower ends of the large diameter portion 71. Furthermore, by setting the diameter of the small diameter portion 72 to (pin hole diameter−straightness tolerance), it is possible to detect the misalignment by the large diameter portion 71 and simultaneously detect the straightness by the small diameter portion 72. Become. That is, when the cell 2 is laminated, the small diameter portion 72 abuts against the inner wall of the pin hole 40 to prevent insertion. As a result, a swell exceeding a specified value can be detected.

In addition, although the large diameter parts 52 and 71 and the pin gauge 66 in each said embodiment are the dimensions corresponding to three cell thickness, it is not restricted to this. For example, the dimension may correspond to a cell thickness greater than three. However, by making it correspond to the thickness of three cells, it is possible to detect a deviation of three cells, one cell and a cell sandwiching this cell from both sides.
Further, the pin hole 40 may be newly provided for the main measurement, but a hole conventionally provided in the cell 2, for example, a reference pin hole used at the time of cell formation may also be used.
In addition, since the pin hole 40, the large-diameter portion 52, the gauge 60, and the like are both circular in cross-sectional view, they can be inserted into the pin hole 40 without considering the angular direction around the gauge axis. It is not limited to this.
Further, similarly to the operation method of the skimming gauge, stacking accuracy can be roughly measured by having several types of gauges.

It is a side view of the cell laminated body of a fuel cell. It is a perspective view of a cell laminated body. It is the figure which showed the gauge which can be used for the cell lamination | stacking deviation confirmation method of the cell laminated body which concerns on this embodiment, and is principal part sectional drawing of the cell laminated body which showed the state by which the gauge was inserted in the pin hole. It is the figure shown about the other example of the gauge. It is the figure shown about the other example of the gauge. It is the figure shown about the other example of the gauge.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Fuel cell, 2 ... Cell, 3 ... Cell laminated body, 40 ... Pin hole, 50 ... Gauge, 51 ... Small diameter part, 52 ... Large diameter part, 60 ... Gauge, 65 ... Gauge, 70 ... Gauge, 71 ... Large diameter part, 72 ... thin diameter part

Claims (4)

In the method for confirming the stacking deviation of the cells constituting the cell stack,
All of the cells form a pin hole at the same position that overlaps each other and penetrates the whole cell stack in a straight line when each cell is stacked straight without stacking misalignment,
The diameter of the portion having the largest diameter is (the hole diameter of the pin hole−lamination misalignment tolerance), and the large diameter portion whose diameter is (the hole diameter of the pin hole−lamination misalignment tolerance); Using a gauge that extends in an axial direction from at least one end, and has a small diameter portion (diameter of the pin hole−lamination straightness tolerance of the cell laminate).
A method for confirming cell stacking misalignment in a fuel cell, wherein a cell stacking misalignment is detected by inserting the gauge into the pin hole. 2. The fuel cell according to claim 1, wherein the portion where the diameter of the gauge is (the hole diameter of the pin hole− lamination deviation tolerance) has a length corresponding to three cells in the gauge axis direction. Cell stacking deviation confirmation method. In the gauge for confirming the stacking deviation of the cells constituting the cell stack,
A gauge used for the cells, in which pin holes are formed at the same position that overlaps each other and penetrates the whole cell stack in a straight line when all the cells are stacked straight without stacking misalignment. In addition , the diameter of the portion where the diameter of the gauge is the maximum is (the hole diameter of the pin hole−lamination misalignment tolerance), and the diameter is (the hole diameter of the pin hole−lamination misalignment tolerance). A gauge having a large-diameter portion and a small-diameter portion extending in an axial direction from at least one end of the large-diameter portion and having a diameter dimension (hole diameter of the pin hole−lamination straightness tolerance of the cell laminate). Oh it is,
A gauge for confirming cell stacking misalignment of a fuel cell, wherein the gauge stacking misalignment is detected by inserting the gauge into the pin hole. 4. The fuel cell according to claim 3, wherein a portion where the diameter of the gauge is (hole diameter of the pin hole− lamination deviation tolerance) has a length corresponding to three cells in the gauge axis direction. Gauge for checking cell stacking deviation.

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