JP2010276520A - Surface pressure distribution detector for laminated battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface pressure distribution detector for laminated batteries, capable of detecting a surface pressure distribution without deteriorating power generation performance. <P>SOLUTION: The surface pressure distribution detector includes an inner insulated section 61 elastically deformable in a laminating direction of a unit cell 10; a plurality of first electrodes 63 disposed on one of side surfaces of the inner insulated section 61; a plurality of second electrodes 62 disposed on the other side surface of the inner insulated section 61 and facing the first electrodes 63; a pair of outer insulated sections 64 disposed between the first electrodes 63 and the unit cell 10 on the first electrode side, and disposed between the second electrodes 62 and the unit cell 10 on the second electrode side; and a plurality of conductive sections 65 configured elastically deformable in the laminating direction, electrically insulated from the first electrodes 63 and the second electrodes 62, and electrically connecting the unit cell 10 on the first electrode side and the unit cell 10 on the second electrode side. A surface pressure distribution measuring section 90 calculates a laminated surface pressure based on a capacitance changing according to a distance between the first electrodes 63 and the second electrodes 62 to obtain a laminated surface pressure distribution. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a surface pressure distribution detection device for a stacked battery in which a plurality of unit cells are stacked.

  In a stacked battery such as a fuel cell or a lithium ion battery, when the stacking surface pressure is low, contact resistance between unit cells or in a unit cell increases, internal loss increases, and power generation performance deteriorates. In addition, in a fuel cell stack having a reaction gas flow path in the in-plane direction of the electrolyte membrane, if the stacking surface pressure becomes too high, the gas flow path is crushed, reducing the supply amount of the reaction gas and generating power. Performance deteriorates. As described above, it is important to maintain an appropriate stacking surface pressure in the stacked battery.

  However, since the distribution of the lamination surface pressure changes due to the ambient temperature, the swelling and shrinkage of the unit cells, etc., it is difficult to make the distribution of the lamination surface pressure uniform in the laminated battery.

  In Patent Document 1, a plurality of actuators are provided on one end plate of a fuel cell stack, and the actuators are operated based on the surface pressure distribution information detected by the surface pressure distribution detection device, so that the stacking surface pressure is made uniform. Techniques to be disclosed are disclosed.

JP 2007-213882 A

  The surface pressure distribution detection device described in Patent Literature 1 has a sheet-like tactile sensor that detects a surface pressure distribution and detects a surface pressure distribution so that a current generated by a unit cell is supplied while detecting a stacked surface pressure. Sandwiched between two large conductive sheets, and the edges of the conductive sheets are electrically joined. In such a surface pressure distribution detection device, the current generated in the unit cell flows in a concentrated manner at the edge of the conductive sheet, so the current density of the generated current is biased and the power generation performance of the fuel cell stack can be degraded. There is sex.

  Therefore, the present invention has been made paying attention to such problems, and provides a surface pressure distribution detection device for a stacked battery that can detect a surface pressure distribution without deteriorating power generation performance. For the purpose.

  The present invention solves the above problems by the following means.

  The present invention is a surface pressure distribution detection device that detects a stack surface pressure distribution of a stacked battery in which a plurality of power generation unit cells are stacked. The surface pressure distribution detector includes an inner insulating portion that can be elastically deformed in the stacking direction of the unit cells, a plurality of first electrodes provided on one side in the stacking direction of the inner insulating portion, and a side in the other stacking direction of the inner insulating portion. A plurality of second electrodes that are opposed to the first electrode, provided between the first electrode and the first electrode side unit cell, and a pair provided between the second electrode and the second electrode side unit cell. And an outer insulating portion. Furthermore, the surface pressure distribution detection device is configured to be elastically deformable in the stacking direction, and in a state of being electrically insulated from the first electrode and the second electrode, the first electrode side unit cell and the second electrode side unit cell are connected to each other. A plurality of conductive parts to be electrically connected are provided. Then, the surface pressure distribution measuring unit calculates the lamination surface pressure based on the capacitance that changes according to the facing distance between the first electrode and the second electrode, and obtains the lamination surface pressure distribution based on the lamination surface pressure. .

  Since the surface pressure distribution detection device of the present invention includes a plurality of conductive portions that are configured to be elastically deformable in the stacking direction and electrically connect the first electrode side unit cell and the second electrode side unit cell. The bias of current density of the current passing through the electrode side unit cell and the second electrode side unit cell can be suppressed, and the surface pressure distribution in the unit cell is detected while suppressing the deterioration of power generation performance due to the current density. It becomes possible to do.

It is a schematic block diagram of the fuel cell stack mounted in a vehicle. It is a schematic block diagram of a combustion battery system. It is a figure explaining the surface pressure detection part with which a fuel cell stack is equipped. It is a figure explaining the electroconductive part of a surface pressure detection part. It is a figure explaining a surface pressure signal detection circuit. It is a schematic block diagram of the surface pressure detection part in 2nd Embodiment. It is a schematic block diagram of the surface pressure detection part in 3rd Embodiment. It is a schematic block diagram of the surface pressure detection part in 4th Embodiment. It is a schematic block diagram of the surface pressure detection part in 5th Embodiment. It is a schematic block diagram of the surface pressure signal detection circuit in 6th Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a schematic configuration diagram of a fuel cell stack 100 mounted on a vehicle.

  As shown in FIG. 1, the fuel cell stack 100 is configured by stacking a plurality of unit cells 10 that are solid polymer fuel cells that generate an electromotive force.

  A current collecting plate 20 and an insulating plate 30 are sequentially provided on both ends of the stacked body of the unit cells 10.

  The current collecting plate 20 is a gas impermeable conductive member, and is formed of dense carbon, for example. The current collector plate 20 is provided with an output terminal 21 for taking out an electromotive force generated in the fuel cell stack 100.

  The insulating plate 30 is disposed outside the current collecting plate 20. The insulating plate 30 is made of insulating rubber or the like.

  An end plate 40 is provided outside one insulating plate 30, and an end plate 40 is provided outside the other insulating plate 30 via a movable plate 50. Between the end plate 40 and the movable plate 50, a surface pressure adjusting device that adjusts the stacked surface pressure of the unit cells 10 is disposed.

  The end plate 40 and the movable plate 50 are formed of a metal material or resin material having rigidity. One end plate 40 of the end plates 40 has a fuel gas inlet 41A for supplying a fuel gas such as hydrogen gas to each unit cell 10, a fuel gas outlet 41B for discharging the fuel gas, and an oxygen for each unit cell 10. An oxidant gas inlet 42A that supplies an oxidant gas such as, an oxidant gas outlet 42B that discharges oxidant gas, a cooling water inlet 43A that supplies cooling water to each unit cell 10, and cooling that discharges cooling water A water outlet 43B is formed.

  The fuel cell stack 100 includes a surface pressure detection unit 60 between two unit cells 10 at an arbitrary position in the stacking direction. The surface pressure detection unit 60 detects pressure on a surface (stacked surface) orthogonal to the stacking direction of the unit cells 10.

  In the present embodiment, one surface pressure detection unit 60 is provided, but a plurality of surface pressure detection units 60 may be provided in the stacking direction. Further, the surface pressure detection unit 60 is provided between the unit cells 10, but the surface pressure detection unit 60 may be provided between the unit cells 10 and the current collector plate 20.

  The unit cell 10, the current collector plate 20, the insulating plate 30, the end plate 40, the movable plate 50, and the surface pressure detecting unit 60 that are stacked are inserted into the through holes at the four corners in the stacked surface, and the end portions of the tie rods 70 are inserted. It is fixed by screwing the nut into the screw. The tie rod 70 is formed of a metal material such as steel. In order to prevent an electrical short circuit, the surface of the tie rod 70 is insulated.

  FIG. 2 is a schematic configuration diagram of the combustion battery system.

  The fuel cell stack 100 includes a plurality of surface pressure adjusting devices 80 between the end plate 40 and the movable plate 50. The surface pressure adjusting device 80 is a piezoelectric actuator or a hydraulic cylinder and expands and contracts in the stacking direction. These surface pressure adjusting devices 80 are controlled by a controller 90.

  The controller 90 includes a microcomputer that includes a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), and an input / output interface (I / O interface). The controller 90 is connected to the surface pressure detection unit 60 through a signal line and detects a surface pressure signal 91, and a surface pressure calculation circuit 92 calculates a stacked surface pressure based on the detected surface pressure signal. Have The controller calculates a surface pressure distribution based on the stack surface pressure at each surface pressure detection position, and drives the surface pressure adjusting device 80 based on the calculated surface pressure distribution to adjust the stack surface pressure.

  With reference to FIG. 3 (A) and FIG. 3 (B), the structure of the surface pressure detection part 60 of the fuel cell stack 100 is demonstrated. FIG. 3A is a partial longitudinal sectional view of the surface pressure detection unit 60, and FIG. 3B is an exploded perspective view of the surface pressure detection unit 60.

  A surface pressure detection unit 60 shown in FIGS. 3A and 3B is a sheet-like member sandwiched between unit cells 10 composed of a membrane electrode assembly (MEA) 11 and a separator 12. The pressure sensor detects the pressure based on the capacitance between the electrodes.

  The surface pressure detection unit 60 includes an inner insulating part 61, a row electrode 62, a column electrode 63, an outer insulating part 64, a conductive part 65, and a spacer 66.

  The inner insulating portion 61 is formed in a sheet shape having substantially the same area as the stacked surface of the unit cells 10 by an electrical insulating material that can be elastically deformed in the stacking direction. The inner insulating portion 61 is formed from an engineering plastic sheet, a fluorine rubber sheet, or the like. The inner insulating portion 61 includes a row electrode 62 on one side surface and a column electrode 63 on the other side surface. In FIG. 3B, the illustration of the inner insulating portion 61 is omitted in order to make the drawing easier to see.

  The row electrode 62 is an electrode formed in a strip shape, and a plurality of row electrodes 62 are provided on the side surface of the inner insulating portion 61. These row electrodes 62 are arranged so that the longitudinal side is horizontal, and are arranged in parallel at a predetermined interval in the vertical direction. In this embodiment, four row electrodes 62 are provided, but the number of row electrodes 62 is not limited to this.

  The column electrode 63 is an electrode formed in a strip shape, and a plurality of column electrodes 63 are provided on the side surface opposite to the side surface of the inner insulating portion 61 provided with the row electrode 62. These column electrodes 63 are arranged so that the longitudinal side is vertical, and are arranged in parallel at a predetermined interval in the horizontal direction. In the present embodiment, four column electrodes 63 are provided, but the number of column electrodes 63 is not limited to this.

  An outer insulating portion 64 is provided outside the row electrode 62 and the column electrode 63. The outer insulating portion 64 is an electrical insulating material and is formed in a sheet shape having substantially the same area as the stacked surface of the unit cells 10. The outer insulating portion 64 electrically insulates the row electrode 62 and the column electrode 63 from the unit cell 10.

  The spacer 66 is provided between the edges of the inner insulating portion 61 and the outer insulating portion 64 and adjusts the distance between the inner insulating portion 61 and the outer insulating portion 64. The thickness of the spacer 66 is set equal to the row electrode 62 and the column electrode 63.

  The conductive part 65 electrically connects the unit cells 10 adjacent to the surface pressure detection part 60. A plurality of conductive portions 65 are provided so as to pass through the gaps between the row electrodes 62 and the column electrodes 63 arranged in a grid pattern, and penetrate the outer insulating portion 64 and the inner insulating portion 61 in the stacking direction. Since the conductive portion 65 is arranged by sewing the gap between the row electrode 62 and the column electrode 63, the conductive portion 65 and the row electrode 62 and the column electrode 63 are electrically insulated. Since the current generated by the unit cell 10 flows in the stacking direction through a plurality of conductive portions 65 provided in the stacking plane, the current distribution in the stacking plane direction is suppressed from being biased.

  In the present embodiment, 15 conductive portions 65 are provided, but the number of conductive portions 65 is not limited to this.

  The conductive portion 65 of the above-described surface pressure detector 60 is configured to be elastically deformable in the stacking direction. With reference to FIGS. 4A to 4D, the conductive portion 65 will be described.

  As shown in FIG. 4A, the conductive portion 65 has a rod shape and includes a large-diameter cylindrical portion 65A disposed at both ends, and a small-diameter cylindrical portion 65B that connects these large-diameter cylindrical portions 65A.

  The large diameter cylindrical portion 65A is open on the unit cell side and has an end face 65C on the opposite side. The small-diameter cylindrical portion 65B is connected to the end faces 65C of the two large-diameter cylindrical portions 65A. The large diameter cylindrical portion 65A and the small diameter cylindrical portion 65B are arranged concentrically.

Referring to FIG. 4 (B) showing the state of the conductive portion 65 when the lamination surface pressure is zero and FIG. 4 (C) showing the state of the conductive portion 65 at the maximum lamination surface pressure, the depth D of the large diameter cylindrical portion 65A. _A and the outer diameter R _A and the length L _B of the small-diameter cylindrical portion 65B are set as follows.

  In the conductive part 65 described above, the end face 65C, which is a joining boundary between the large diameter cylindrical part 65A and the small diameter cylindrical part 65B, functions as a diaphragm. Therefore, as shown in FIGS. 4B and 4C, the conductive part 65 is laminated. It can be elastically deformed in the direction. In the fuel cell stack 100, even if the lamination surface pressure changes due to the ambient temperature or the swelling / shrinkage of the unit cell 10, the conductive portion 65 is quickly deformed in the lamination direction, so that the displacement of the inner insulating portion 61 and the electrodes 62, 63 Will not be disturbed.

  In addition, as shown in FIG. 4D, even if the end face 65C functioning as a diaphragm is plastically deformed due to a large lamination surface pressure, the inner insulating portion is interposed between the row electrode 62 and the column electrode 63. 61 is interposed, and the deformation of the row electrode 62 and the column electrode 63 is suppressed by the restoring force of the inner insulating portion 61. Therefore, even if the end face 65C is plastically deformed, the lamination surface pressure detection accuracy does not deteriorate.

  In the conductive portion 65, as shown in FIG. 4A, the large-diameter cylindrical portion 65A and an external voltmeter 93 are connected via a signal line 93A provided inside the outer insulating portion 64. . The voltmeter 93 detects a potential difference Vi between both ends of the conductive portion 65. The controller 90 calculates the current value I flowing through the conductive portion 65 for each conductive portion 65 based on the potential difference Vi detected by the voltmeter 93 and the electrical resistance value R obtained by the shape and volume resistivity of the conductive portion 65. Then, the current density of the generated current passing through the surface pressure detection unit 60 is calculated.

  With reference to FIGS. 5A and 5B, the detection of the surface pressure distribution in the fuel cell stack 100 will be described. FIG. 5A shows a configuration of a surface pressure signal detection circuit 91 provided in the controller 90. FIG. 5B shows the configuration of the capacitance detection circuit 91 </ b> C in the surface pressure signal detection circuit 91.

  The surface pressure signal detection circuit 91 of the controller 90 includes a row electrode side switch circuit 91A, a column electrode side switch circuit 91B, and a capacitance detection circuit 91C.

  The row electrode side switch circuit 91 </ b> A has switches Sr <b> 1 to Sr <b> 4 for each row electrode 62 of the surface pressure detection unit 60. The switches Sr1 to Sr4 are connected to the row electrodes 62 through signal lines R1 to R4.

  The column electrode side switch circuit 91 </ b> B has switches Sc <b> 1 to Sc <b> 4 for each column electrode 63 of the surface pressure detection unit 60. The switches Sc1 to Sc4 are connected to the column electrodes 63 via signal lines C1 to C4.

  The electrostatic capacitance detection circuit 91C detects the electrostatic capacitance Cd between the row electrode 62 and the column electrode 63 selected by the row electrode side switch circuit 91A and the column electrode side switch circuit 91B.

  When detecting the surface pressure, one of the switches Sr1 to Sr4 of the row electrode side switch circuit 91A is turned on, the other is turned off, and any one of the switches Sc1 to Sc4 of the column electrode side switch circuit 91B is turned on. With the others turned off, 16 surface pressure detection positions are sequentially selected. The capacitance detection circuit 91C includes a row electrode signal Cin + and a column electrode signal Cin− at the position (surface pressure detection position) where the row electrode 62 and the column electrode 63 face each other in the selected row electrode 62 and column electrode 63. Enter. Based on the row electrode signal Cin + and the column electrode signal Cin−, the capacitance detection circuit 91C adds position information r and c indicating the surface pressure detection position and outputs the capacitance Cd.

  The capacitance detection circuit 91C outputs the voltage signal G having the same potential as the high potential side of the selected row electrode 62 and column electrode 63 to the row electrode 62 and the column electrode 63 in the non-selected state. It is configured. That is, the voltage signal G is supplied to the row electrode side switch circuit 91A and the column electrode side switch circuit 91B, and is applied to the row electrode 62 and the column electrode 63 in the off state. As a result, the potential difference between the on-state row electrode 62 and column electrode 63 and the off-state row electrode 62 and column electrode 63 becomes zero, and no stray capacitance is formed between the signal lines. The capacitance detected by the capacitance detection circuit 91C is only the capacitance formed between the row electrode 62 and the column electrode 63 in the on state. Similarly, in the signal lines connected to the row electrode 62 and the column electrode 63 that are in the off state, the potential difference is zero, so that no stray capacitance is formed. According to the surface pressure signal detection circuit 91 having such a configuration, it is possible to increase the detection accuracy of the capacitance between the row electrode 62 and the column electrode 63 at the surface pressure detection position.

  The capacitance detection circuit 91C described above includes an operational amplifier 911, a capacitor 912, an AC signal source 913, a transformer 914, and a capacitance calculation circuit 915, as shown in FIG.

  The ON-side signal line of the row electrode side switch circuit 91A is connected to the inverting input terminal of the operational amplifier 911. The non-inverting input terminal of the operational amplifier 911 is connected to the off-side signal lines of the row electrode side switch circuit 91A and the column electrode side switch circuit 91B. A capacitor 912 having a reference capacitance Cr is provided between the output portion of the operational amplifier 911 and the inverting input terminal.

  The ON-side signal line of the column electrode side switch circuit 91B is connected to the reference potential GND and also connected to the non-inverting input terminal of the operational amplifier 911 via the AC signal source 913.

  The transformer 914 extracts only the detection signal Vd from the detection signal Vd and the measurement AC signal Vosc included in the output of the operational amplifier 911.

  The capacitance calculation circuit 915 outputs the capacitance Cd between the row electrode 62 and the column electrode 63 at the surface pressure detection position based on the following equation.

  Based on the capacitance Cd between the row electrode 62 and the column electrode 63 calculated as described above, the controller 90 obtains the surface pressure P at the surface pressure detection position from Equations (5) and 6 (Equation), The surface pressure distribution on the laminated surface is calculated from the surface pressure P at the entire surface pressure detection position.

  As described above, the surface pressure distribution detection device according to the first embodiment can obtain the following effects.

  The surface pressure detection unit 60 electrically connects adjacent unit cells 10 and elastically deforms the conductive unit 65 in the stacking direction in a state in which the row electrode 62 and the column electrode 63 are electrically insulated from each other. A plurality of regions are provided in regions corresponding to the electrode surfaces of the cell 10. Therefore, it is possible to suppress a deviation in current density of current flowing from the electrode surface of the unit cell 10 via the surface pressure detection unit 60. Therefore, the surface pressure detection unit 60 can detect the surface pressure distribution in the fuel cell stack 100 while suppressing the deterioration of the power generation performance due to the current density.

  The conductive portion 65 is formed by connecting two large-diameter cylindrical portions 65A by a small-diameter cylindrical portion 65B so that the conductive portion 65 can be expanded and contracted in the stacking direction. Even if the pressure changes, the displacement of the inner insulating portion 61 and the electrodes 62 and 63 is not hindered, and the surface pressure detection accuracy can be improved.

  Since the conductive portion 65 is provided so as to pass through the gap between the row electrode 62 and the column electrode 63 arranged in a lattice shape and penetrate the outer insulating portion 64 and the inner insulating portion 61 in the stacking direction, the surface pressure detecting portion 60 is provided. Can be prevented from becoming large.

  Since the current value flowing through each conductive portion 65 is detected using a voltmeter 93 provided outside, the surface pressure detector 60 not only detects the laminated surface pressure distribution but also the current density distribution of the generated current in real time. Can be detected.

(Second Embodiment)
The surface pressure distribution detection device according to the second embodiment has substantially the same configuration as that of the first embodiment, but differs in the configuration of the conductive portion 65 of the surface pressure detection unit 60. Hereinafter, the difference will be mainly described.

  FIG. 6A is a partial vertical cross-sectional view of the surface pressure detection unit 60. FIG. 6B is an exploded perspective view of the surface pressure detection unit 60. In FIG. 6B, the illustration of the inner insulating portion 61 is omitted for easy understanding of the drawing.

  In the first embodiment, the conductive portion 65 is provided so as to penetrate the surface pressure detection unit 60 in the stacking direction. However, in the second embodiment, the conductive portion 65 is provided outside the surface pressure detection unit 60.

  The conductive portion 65 is a member that electrically connects the adjacent unit cells 10 and is formed of a material having high electrical conductivity and thermal conductivity, such as a thin plate of copper or aluminum. The conductive portion 65 is formed in a band shape and is folded in two so as to straddle the outer edge portions of the pair of outer insulating portions 64. The current collecting portion 65D on one end side of the conductive portion 65 is connected to the outside of the outer insulating portion 64 on the row electrode 62 side, and the current collecting portion 65D on the other end side is connected to the outside of the outer insulating portion 64 on the column electrode 63 side. . Since the conductive portion 65 is formed by being folded in half, it can be elastically deformed in the stacking direction.

  As shown in FIG. 6B, four conductive portions 65 are provided on one end side of the outer insulating portion 64, and four conductive portions 65 are also provided on the other end side. These conductive parts 65 are provided in a horizontal state and are arranged so as to be parallel to the vertical direction.

  Note that the total area of the current collectors 65 </ b> D of each conductive part 65 is set to be approximately equal to the area of the electrode surface of the unit cell 10.

  As described above, in the surface pressure distribution detection device of the second embodiment, the following effects can be obtained.

  The surface pressure detection unit 60 is folded in two so as to straddle the outer edge portions of the pair of outer insulating portions 64, the current collecting portion 65D on one end side is installed outside the outer insulating portion 64 on the row electrode 62 side, and the other end Since the current collector 65D on the side includes a plurality of conductive parts 65 installed outside the outer insulating part 64 on the column electrode 63 side, the stacking surface pressure is maintained while maintaining the current distribution state in the in-plane direction of the extraction current of the unit cell 10 Distribution can be detected.

  In addition, the conductive portion 65 can be folded in half to be elastically deformed in the stacking direction. Even if the stack surface pressure changes due to the ambient temperature or the swelling shrinkage of the unit cell 10 in the fuel cell stack 100, the inner insulating portion The surface pressure can be detected with high sensitivity without hindering the displacement of the electrode 61 and the electrodes 62 and 63.

(Third embodiment)
The surface pressure distribution detection device according to the third embodiment has substantially the same configuration as that of the first embodiment, but differs in the configuration of the inner insulating portion 61 of the surface pressure detection unit 60. Hereinafter, the difference will be mainly described.

  FIG. 7A is a plan view of the surface pressure detection unit 60 viewed from the unit cell side. FIG. 7B is a BB cross-sectional view of the surface pressure detection unit 60 in FIG.

  As shown in FIGS. 7A and 7B, the inner insulating portion 61 is located between the row electrode 62 and the column electrode 63, and the air is located at a position where the row electrode 62 and the column electrode 63 face each other. A chamber 61A is provided. The air chamber 61A is formed in a cylindrical shape having a diameter r.

  The surface pressure detection unit 60 includes a current collecting layer 67 outside the outer insulating unit 64. The conductive portion 65 is electrically connected to the adjacent unit cell 10 via the current collecting layer 67. The current collecting layer 67 on the column electrode 63 side forms a groove 67A extending in the in-plane direction.

  In the column electrode 63 and the outer insulating portion 64 on the column electrode 63 side, through holes 63A and 64A are formed to communicate the air chamber 61A of the inner insulating portion 61 and the groove portion 67A of the current collecting layer 67.

  As described above, in the surface pressure detection unit 60 of the present embodiment, outside air can freely enter and exit the air chamber 61A of the inner insulating portion 61.

  As described above, in the surface pressure distribution detection device according to the third embodiment, the following effects can be obtained.

  Since the inner insulating portion 61 of the surface pressure detection unit 60 includes the air chamber 61A at a position where the row electrode 62 and the column electrode 63 face each other, the dielectric constant in the electrostatic capacitance between the row electrode 62 and the column electrode 63 is air. The dielectric constant of becomes dominant. Since the dielectric constant of air is almost equal to the dielectric constant in vacuum and the temperature coefficient is small, even if the temperature environment of the surface pressure detector 60 changes greatly, the temperature-dependent variation amount of the detected capacitance is kept low. be able to. Therefore, it is possible to reduce the temperature dependent error of the lamination surface pressure calculated based on the capacitance.

  In addition, since the air chamber 61A of the inner insulating portion 61 is configured to communicate with the outside air, the pressure in the air chamber 61A can be kept constant even if the temperature environment of the surface pressure detecting portion 60 changes greatly, It is possible to reduce a surface pressure detection error caused by a pressure change in the air chamber 61A.

  If the air chamber 61A is formed in the inner insulating portion 61, the rigidity of the surface pressure detecting portion 60 in the stacking direction is reduced. Accordingly, when the high surface pressure distribution is detected by the surface pressure detector 60, as shown in FIG. 7C, a support member 61B for supporting the row electrode 62 and the column electrode 63 is provided in the air chamber 61A. Thus, the bending rigidity of the row electrode 62, the column electrode 63, and the outer insulating portion 64 may be reinforced. It is desirable to select a support member 61B having a dielectric constant temperature coefficient as small as possible. In the surface pressure detection unit 60, the composite dielectric constant between the row electrode 62 and the column electrode 63 affects the detection sensitivity. Therefore, if a material having a large temperature coefficient is selected, the temperature-dependent error of the detected capacitance increases. Because.

(Fourth embodiment)
The surface pressure distribution detection device according to the fourth embodiment has substantially the same configuration as that of the third embodiment, but differs in the configuration of the inner insulating portion 61 of the surface pressure detection unit 60. Hereinafter, the difference will be mainly described. FIG. 8A is a perspective view of the inner insulating portion 61 of the surface pressure detecting portion 60. FIG. 8B shows a B cross section of the inner insulating portion 61 in FIG.

  In the third embodiment, the air chamber 61A of the inner insulating portion 61 is configured to communicate with the outside air. However, in this embodiment, the air chamber 61A of the inner insulating portion 61 is connected to the row electrode 62 as shown in FIG. And the column electrode 63 are hermetically sealed.

  Further, as shown in FIGS. 8 (A) and 8 (B), the inner insulating portion 61 includes a communication passage 61C for communicating adjacent air chambers 61A and one of the air chambers 61A disposed at the corners. And a connection passage 61D for connecting the pressure adjusting device 94.

  The pressure adjusting device 94 is a device that adjusts the pressure in the air chamber 61A by supplying dry air into the air chamber 61A or sucking out the dry air in the air chamber 61A.

  As described above, the following effects can be obtained in the surface pressure distribution detection apparatus of the fourth embodiment.

  In the surface pressure detector 60, the surface pressure detection sensitivity (measurement range) changes depending on the ease of deformation of the insulator between the row electrode 62 and the column electrode 63. In the present embodiment, since the pressure of the air chamber 61A formed in the inner insulating portion 61 can be adjusted by the pressure adjusting device 94, the surface pressure detection sensitivity in the surface pressure detection unit 60 can be changed. When the surface pressure detection sensitivity can be selected in this way, the application range of the surface pressure detection unit 60 is expanded.

  Further, since the air chamber 61A is configured to be hermetically sealed, it is possible to prevent moisture, dust, or the like that causes deterioration of the surface pressure detection accuracy from entering the air chamber 61A.

(Fifth embodiment)
The surface pressure distribution detection apparatus according to the fifth embodiment has substantially the same configuration as that of the first embodiment, but differs in the configuration of the row electrode 62 and the column electrode 63 of the surface pressure detection unit 60. Hereinafter, the difference will be mainly described. FIG. 9A is a diagram schematically illustrating the row electrode 62 and the column electrode 63 of the surface pressure detection unit 60. FIG. 9B is a diagram illustrating an arrangement state of the column electrodes 63 with respect to the row electrodes 62.

As shown in FIG. 9 (A), the row electrodes 62 of the surface pressure detector 60 forms the shape of the surface pressure detection position facing the column electrode 63 into a circle with a diameter r _A. Four circular portions are formed in one row electrode 62.

On the other hand, the column electrodes 63 form a shape of the surface pressure detection position opposing the row electrode 62 in a circular shape having a diameter of r _B. The diameter r _B of the circular part of the column electrode 63 is set smaller than the diameter r _A of the circular part of the row electrode 62. Four circular portions are formed in one column electrode 63.

  In the surface pressure detection unit 60, the column electrode 63 may be displaced in the in-plane direction with respect to the row electrode 62 due to the manufacture of the surface pressure detection unit 60 or a change with time. In this embodiment, since the row electrode 62 and the column electrode 63 are configured as described above, even if the column electrode 63 is displaced from the row electrode 62 as shown in FIG. The substantial effective detection area of the electrode 62 and the column electrode 63 is the area of the circular portion of the column electrode 63, and the effective detection area does not change greatly.

  As described above, in the surface pressure distribution detection device of the fifth embodiment, the following effects can be obtained.

  Since the column electrode 63 of the surface pressure detection unit 60 is formed so that the shape of the surface pressure detection position facing the row electrode 62 is larger than the area of the row electrode 62, positioning corresponding to the area difference at the surface pressure detection position is performed. Crossing is allowed, and deterioration of surface pressure detection accuracy due to a shift between the row electrode 62 and the column electrode 63 can be suppressed.

(Sixth embodiment)
The surface pressure distribution detection device according to the sixth embodiment has substantially the same configuration as that of the first embodiment, but differs in the configuration of the surface pressure signal detection circuit 91 of the controller 90. Hereinafter, the difference will be mainly described. FIG. 10 is a diagram illustrating a configuration of the surface pressure signal detection circuit 91 of the controller 90.

  The surface pressure signal detection circuit 91 according to the first embodiment is configured such that the row electrode side switch circuit 91A and the column electrode side switch circuit 91B are connected to the capacitance detection circuit 91C. In contrast, in the present embodiment, each row electrode 62 is provided with a capacitance detection circuit 91C, and each capacitance detection circuit 91C is connected to the column electrode side switch circuit 91B. Therefore, the row electrode signal Cin + from each row electrode 62 is always input to each capacitance detection circuit 91C.

  The column electrode side switch circuit 91 </ b> B has switches Sc <b> 1 to Sc <b> 4 for each column electrode 63. When the switches Sc1 to Sc4 are turned on, the column electrode signal Cin− is output from the column electrode side switch circuit 91B to each capacitance detection circuit 91C. When the switches Sc1 to Sc4 are turned off, a voltage signal G having the same potential as that of the AC signal source 913 is output from the capacitance detection circuit 91C to the column electrode side switch circuit 91B.

  The AC signal source 913 is common to the four capacitance detection circuits 91C.

  In the present embodiment, at the time of detecting the surface pressure, one of the switches Sc1 to Sc4 of the column electrode side switch circuit 91B is turned on and the other is turned off, and the surfaces at the four surface pressure detection positions in one column electrode 63 are turned on. The pressure is detected at the same time. Then, the surface pressure at the entire pressure detection position is detected by sequentially changing the switches Sc1 to Sc4 to be turned on.

  As described above, in the surface pressure distribution detection device according to the sixth embodiment, the following effects can be obtained.

  In the present embodiment, since the capacitance detection circuit 91C is provided for each row electrode 62, one column electrode is turned on by turning on one of the switches Sc1 to Sc4 of the column electrode side switch circuit 91B when detecting the surface pressure. The surface pressures at the four surface pressure detection positions in 63 can be detected simultaneously. Thereby, the surface pressure detection speed can be increased as compared with the first embodiment, and the time required for detecting the surface pressure distribution can be shortened.

  When simultaneously measuring capacitance at a plurality of positions of one column electrode 63, signal interference with adjacent column electrodes 63 becomes a problem. In this embodiment, the AC signal source 913 is connected to the total capacitance detection circuit 91C. Therefore, the column electrodes 63 are equivalently insulated so that signal interference can be avoided.

  Note that the present invention is not limited to the above-described embodiment, and it is obvious that various modifications can be made within the scope of the technical idea.

  In the first to sixth embodiments described above, the case of the fuel cell has been described. However, the surface pressure distribution detection device in the present invention can also be applied to a stacked battery such as a lithium ion battery in which a plurality of unit cells are stacked.

DESCRIPTION OF SYMBOLS 100 Fuel cell stack 10 Unit cell 60 Surface pressure detection part 61 Inner insulation part 61A Air chamber 61B Support member 61C Communication path 62 Row electrode (2nd electrode)
63 row electrode (first electrode)
64 Outer insulating part 65 Conductive part 65A Large diameter cylindrical part 65B Small diameter cylindrical part 65C End face 65D Current collecting part 90 Controller (surface pressure distribution measuring part)
91 Surface pressure signal detection circuit 91A Row electrode side switch circuit (second electrode selection unit)
91B Column electrode side switch circuit (first electrode selection unit)
91C Capacitance detection circuit (capacitance calculation unit)
92 Surface Pressure Calculation Circuit 93 Voltmeter 94 Pressure Adjustment Device

Claims (12)

In the surface pressure distribution detection device for detecting the stack surface pressure distribution of a stacked battery in which a plurality of power generation unit cells are stacked,
An inner insulating portion that is elastically deformable in the stacking direction of the unit cells;
A plurality of first electrodes provided on one side in the stacking direction of the inner insulating portion;
A plurality of second electrodes provided on the other side in the stacking direction of the inner insulating portion and facing the first electrode;
A pair of outer insulating portions provided between the first electrode and the first electrode side unit cell, and provided between the second electrode and the second electrode side unit cell;
The first electrode side unit cell and the second electrode side unit cell are electrically connected while being elastically deformable in the stacking direction and being electrically insulated from the first electrode and the second electrode. A plurality of conductive parts;
A surface pressure distribution measuring unit that calculates a lamination surface pressure based on a capacitance that varies according to a facing distance between the first electrode and the second electrode, and obtains a lamination surface pressure distribution based on the lamination surface pressure;
A surface pressure distribution detecting device comprising: The first electrode is an electrode formed in a strip shape, and is disposed in parallel to one side in the stacking direction of the inner insulating portion,
The second electrode is an electrode formed in a strip shape, and is disposed parallel to each other on the other side in the stacking direction of the inner insulating portion and intersects the first electrode at right angles. Provided,
The surface pressure distribution detection apparatus according to claim 1, wherein The conductive portion is formed so as to penetrate the inner insulating portion and the outer insulating portion in the stacking direction, and a pair of large diameter cylindrical portions that are in contact with the first electrode side unit cell and the second electrode side unit cell. And a small-diameter cylindrical portion that connects the pair of large-diameter cylindrical portions, and allows the end surface of the large-diameter cylindrical portion connected to the small-diameter cylindrical portion to function as a diaphragm so as to be elastically deformable in the stacking direction
The surface pressure distribution detection apparatus according to claim 1 or 2, wherein The conductive part is formed in a band shape, and has a current collecting part disposed outside the outer insulating part at both ends, and is folded in two across the edge of the outer insulating part so as to be elastically deformable in the stacking direction. To
The surface pressure distribution detection apparatus according to claim 1 or 2, wherein The inner insulating portion forms an air chamber between the first electrode and the second electrode facing each other;
The surface pressure distribution detection device according to claim 1, wherein The air chamber of the inner insulating portion is configured to communicate with the atmosphere.
The surface pressure distribution detecting apparatus according to claim 5. A pressure adjusting device for adjusting the pressure in the air chamber of the inner insulating portion;
The surface pressure distribution detecting apparatus according to claim 5. The electrode area at the surface pressure detection position of one electrode is made larger than the other electrode area so that one electrode of the first electrode and the second electrode facing each other includes the other electrode region.
The surface pressure distribution detection apparatus according to claim 1, wherein The surface pressure distribution measuring unit calculates a current value flowing through the conductive part based on a potential difference between both ends of the conductive part, and detects a current value distribution in the stacked surface based on the calculated current value.
The surface pressure distribution detection apparatus according to claim 1, wherein The surface pressure distribution measuring unit is
A first electrode selector that selects one electrode from the plurality of first electrodes;
A second electrode selector that selects one electrode from the plurality of second electrodes;
A capacitance calculating unit that calculates a capacitance between the first electrode and the second electrode that are sequentially selected;
Calculate the lamination surface pressure based on the capacitance at the whole surface pressure detection position, and obtain the lamination surface pressure distribution.
The surface pressure distribution detecting device according to claim 2. The surface pressure distribution measuring unit is
A first electrode selector that selects one electrode from the plurality of first electrodes;
A capacitance calculating unit that is provided for each of the second electrodes and that simultaneously calculates the capacitance between each of the second electrodes and the selected first electrode;
Calculate the lamination surface pressure based on the capacitance at the whole surface pressure detection position, and obtain the lamination surface pressure distribution.
The surface pressure distribution detecting device according to claim 2. The surface pressure distribution measurement unit applies a voltage having the same potential difference as the potential difference between the selected electrodes to the first electrode and the second electrode that are not selected.
The surface pressure distribution detection apparatus according to claim 10 or claim 11, wherein

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