JP5471326B2

JP5471326B2 - Fuel cell

Info

Publication number: JP5471326B2
Application number: JP2009257594A
Authority: JP
Inventors: 義治小林
Original assignee: Fuji Electric Co Ltd
Current assignee: Fuji Electric Co Ltd
Priority date: 2009-11-11
Filing date: 2009-11-11
Publication date: 2014-04-16
Anticipated expiration: 2029-11-11
Also published as: JP2011103219A

Description

本発明は、電気化学反応を利用して発電する燃料電池に関し、特にリン酸液などの電解液を含浸した電解質層を備える燃料電池に関する。 The present invention relates to a fuel cell that generates electricity using an electrochemical reaction, and more particularly to a fuel cell including an electrolyte layer impregnated with an electrolyte such as a phosphoric acid solution.

近年、ＣＯ２排出削減などの観点から、燃料ガス及び酸化剤ガスが持つ化学エネルギーを電気化学反応により直接電気エネルギーへ変換する燃料電池が脚光を浴びている。燃料電池は、発電で発生する電気及び発熱を共に利用するコージェネレーションシステムとしても利用でき、エネルギーの有効活用の観点からも注目を集めている。燃料電池は、使用される電解質の種類に応じて区分され、固体高分子形燃料電池（ＰＥＦＣ：Polymer Electrolyte Fuel Cell）、溶融炭酸塩形燃料電池（ＭＣＦＣ：Molten Carbonate Fuel Cell）、固体酸化形燃料電池（ＳＯＦＣ：Solid Oxide Fuel Cell）及びリン酸形燃料電池（ＰＡＦＣ：Phosphoric Acid Fuel Cell）など種々タイプの実用化が検討されている。 In recent years, fuel cells that convert the chemical energy of fuel gas and oxidant gas directly into electrical energy through electrochemical reactions have been highlighted from the viewpoint of reducing CO2 emissions. The fuel cell can be used as a cogeneration system that uses both electricity and heat generated by power generation, and has attracted attention from the viewpoint of effective use of energy. Fuel cells are classified according to the type of electrolyte used, polymer electrolyte fuel cells (PEFC), molten carbonate fuel cells (MCFC), and solid oxide fuels. Various types of practical applications such as a battery (SOFC: Solid Oxide Fuel Cell) and a phosphoric acid fuel cell (PAFC) have been studied.

これらの燃料電池の中でも、リン酸形燃料電池は、運転温度が１５０℃〜２００℃程度と比較的低温であることから、特殊な耐熱材料を必要とせず、運転条件の変化にも柔軟に対応することができる。また、リン酸形燃料電池は、運転温度が適度に高いため、発電に伴う発熱を空調や温水の調整などに利用することができ、業務用や工業用のコージェネレーションシステムとして商用化されている。リン酸形燃料電池を用いたコージェネレーションシステムは、例えば、バイオマスガスシステムにおいて、消化槽で発生したメタンガスを発電に利用し、発電に伴って発生した熱エネルギーをバイオマスガスシステムの消化槽の保温に用いる用途や、ＬＰガスを燃料とした災害時における非常電源としての用途など、更なる用途の拡大が期待されている。 Among these fuel cells, phosphoric acid fuel cells have a relatively low operating temperature of about 150 ° C to 200 ° C, so they do not require special heat-resistant materials and can respond flexibly to changes in operating conditions. can do. In addition, phosphoric acid fuel cells have a moderately high operating temperature, so heat generated by power generation can be used for air conditioning and warm water adjustment, and are commercialized as commercial and industrial cogeneration systems. . Cogeneration systems using phosphoric acid fuel cells, for example, in biomass gas systems, use methane gas generated in digestion tanks for power generation, and heat energy generated by power generation is used to keep digestion tanks in biomass gas systems warm. Further expansion of applications is expected, such as the application to be used and the application as an emergency power source at the time of disaster using LP gas as fuel.

リン酸形燃料電池としては、リン酸形燃料電池の単電池を複数積層した電池積層部と、当該電池積層部の積層方向の上面及び下面に配置され、電池積層部を締付する締付板と、電池積層部を固定する架台とを備えたものが提案されている（例えば、特許文献１参照）。 As the phosphoric acid fuel cell, a battery stacking unit in which a plurality of phosphoric acid fuel cell cells are stacked, and a clamping plate that is disposed on the upper and lower surfaces in the stacking direction of the cell stacking unit and tightens the cell stacking unit And a thing provided with the mount which fixes a battery lamination part is proposed (for example, refer to patent documents 1).

図９、図１０を参照して、一般的なリン酸形燃料電池について説明する。図９は、一般的なリン酸形燃料電池の積層構造を示す図である。図９に示すように、リン酸形燃料電池の電池積層部１１は、複数のリン酸形燃料電池の単電池１２が積層されて構成される。各単電池１２間は、セパレート板１３ａ、１３ｂによってそれぞれ遮蔽されている。各単電池１２は、電解液としてのリン酸液を保持した電解質層１４と、電解質層１４の一方の面側に配置される燃料極１５と、電解質層１４の他方の面側に配置される酸化剤極１６とを主に備える。燃料極１５とセパレート板１３ａとの間には、燃料極１５に燃料ガスを供給するガス流路（溝）が設けられた基材１７ａが配置されている。酸化剤極１６と他方のセパレート板１３ｂとの間には、酸化剤極１６に酸化剤ガスを供給するガス流路（溝）が設けられた基材１７ｂが配置されている。各単電池１２を遮蔽するセパレート板１３ａ、１３ｂの間には、冷却水などの冷媒により電池積層部１１内を冷却する冷却板１８ａ、１８ｂが配置されている。 A general phosphoric acid fuel cell will be described with reference to FIGS. FIG. 9 is a view showing a laminated structure of a general phosphoric acid fuel cell. As shown in FIG. 9, the cell stack part 11 of the phosphoric acid fuel cell is configured by laminating a plurality of single cells 12 of a phosphoric acid fuel cell. Each cell 12 is shielded by separate plates 13a and 13b. Each unit cell 12 is disposed on an electrolyte layer 14 holding a phosphoric acid solution as an electrolytic solution, a fuel electrode 15 disposed on one surface side of the electrolyte layer 14, and the other surface side of the electrolyte layer 14. An oxidizer electrode 16 is mainly provided. Between the fuel electrode 15 and the separation plate 13a, a base material 17a provided with a gas flow path (groove) for supplying fuel gas to the fuel electrode 15 is disposed. Between the oxidant electrode 16 and the other separation plate 13b, a base material 17b provided with a gas flow path (groove) for supplying an oxidant gas to the oxidant electrode 16 is disposed. Cooling plates 18a and 18b for cooling the inside of the battery stack portion 11 with a coolant such as cooling water are disposed between the separate plates 13a and 13b that shield each unit cell 12.

図１０は、一般的なリン酸形燃料電池の構造を示す断面模式図である。図１０に示すように、電池積層部１１の上面及び下面には、貫通孔を有する締付板９１ａ、９１ｂが配置されている。締付板９１ａ、９１ｂの貫通孔には、電池積層部１１を締付する締付スタッド９２が挿通されている。締付スタッド９２の下端には、ナット９４ａが締結され、ナット９４ａと締付板９１ａとの間には、締付板９１ａと締付スタッド９２との間を絶縁する絶縁カラー９３ａが介在している。一方、締付スタッド９２の上端には、ナット９４ｂが締結され、ナット９４ｂと締付板９１ｂとの間には、締付板９１ｂと締付スタッド９２との間を絶縁する絶縁カラー９３ｂが介在している。このように、電池積層部１１は、ナット９４ａ、９４ｂにより締付板９１ａ、９１ｂを介して加圧締付可能に構成され、各単電池１２間の電気的な接続が確保されると共に、燃料ガス及び酸化剤ガスがシールされている。締付板９１ａ、９１ｂには、電池積層部１１で発電された直流電流を出力する出力端子９５ａ、９５ｂが設けられている。電池積層部１１は、締付板９１ｂの下面に配置された絶縁支持碍子９６を介して架台９７に固定されている。 FIG. 10 is a schematic cross-sectional view showing the structure of a general phosphoric acid fuel cell. As shown in FIG. 10, fastening plates 91 a and 91 b having through holes are disposed on the upper and lower surfaces of the battery stack 11. Fastening studs 92 for fastening the battery stack 11 are inserted through the through holes of the fastening plates 91a and 91b. A nut 94a is fastened to the lower end of the fastening stud 92, and an insulating collar 93a that insulates the fastening plate 91a from the fastening stud 92 is interposed between the nut 94a and the fastening plate 91a. Yes. On the other hand, a nut 94b is fastened to the upper end of the fastening stud 92, and an insulating collar 93b that insulates the fastening plate 91b from the fastening stud 92 is interposed between the nut 94b and the fastening plate 91b. doing. As described above, the battery stacking portion 11 is configured to be pressure-tightened by the nuts 94a, 94b via the fastening plates 91a, 91b, and the electrical connection between the single cells 12 is ensured and the fuel is secured. Gas and oxidant gas are sealed. The fastening plates 91a and 91b are provided with output terminals 95a and 95b for outputting a direct current generated by the battery stacking unit 11. The battery stack portion 11 is fixed to the gantry 97 via an insulating support insulator 96 disposed on the lower surface of the fastening plate 91b.

次に、図１１を参照して、図９、図１０に示すリン酸形燃料電池の電気的な接続について説明する。図１１に示すように、電池積層部１１は、各単電池１２が直列に接続されて構成され、上部の出力端子９５ｂが負極（−）側となり、下部の出力端子９５ａが正極（＋）側となる。また、電池積層部１１の中間部には、単電池１２間の電位差が最小になるように、接地線９８が接地検出リレー９９を介してアース接続されている。接地検出リレー９９は、接地線９８を介して流れる地絡電流を検出することにより地絡の発生を検出し、一定の閾値を超えた場合には、安全ため、発電を停止するように構成されている。 Next, the electrical connection of the phosphoric acid fuel cell shown in FIGS. 9 and 10 will be described with reference to FIG. As shown in FIG. 11, the battery stack portion 11 is configured by connecting the single cells 12 in series, the upper output terminal 95 b is on the negative electrode (−) side, and the lower output terminal 95 a is on the positive electrode (+) side. It becomes. In addition, a ground wire 98 is grounded via a ground detection relay 99 at the intermediate portion of the battery stack portion 11 so that the potential difference between the single cells 12 is minimized. The ground detection relay 99 is configured to detect the occurrence of a ground fault by detecting a ground fault current flowing through the ground line 98, and to stop power generation for safety when a certain threshold is exceeded. ing.

次に、リン酸形燃料電池の発電動作について説明する。燃料ガス及び酸化ガスは、燃料ガス導入口及び酸化ガス導入口（不図示）を介して、電池積層部１１に供給される。電池積層部１１に供給された燃料ガスは、基材１７ａを介して燃料極１５に供給される。燃料極１５に供給された燃料ガスは、燃料極１５の電解質層１４側表面の電極触媒層で電気化学反応に供される。一方、電池積層部１１に供給された酸化剤ガスは、基材１７ｂを介して酸化剤極１６へ供給される。酸化剤極１６へ供給された酸化剤ガスは、酸化剤極１６の電解質層１４側表面の電極触媒層で電気化学反応に供される。以上のようにして、リン酸形燃料電池では、電解質層１４を介して、燃料ガス、酸化剤ガス、リン酸溶液による電気化学反応が進行して発電動作が行われる。電池積層部１１で発電された直流電流は、上下の締付板９１ａ、９１ｂの出力端子９５ａ、９５ｂにより取出され、直交変換装置（不図示）により、交流変換されて商用電力として使用される。 Next, the power generation operation of the phosphoric acid fuel cell will be described. The fuel gas and the oxidizing gas are supplied to the battery stack 11 through the fuel gas inlet and the oxidizing gas inlet (not shown). The fuel gas supplied to the battery stack portion 11 is supplied to the fuel electrode 15 via the base material 17a. The fuel gas supplied to the fuel electrode 15 is subjected to an electrochemical reaction in the electrode catalyst layer on the surface of the fuel electrode 15 on the electrolyte layer 14 side. On the other hand, the oxidant gas supplied to the battery stack 11 is supplied to the oxidant electrode 16 through the base material 17b. The oxidant gas supplied to the oxidant electrode 16 is subjected to an electrochemical reaction in the electrode catalyst layer on the surface of the oxidant electrode 16 on the electrolyte layer 14 side. As described above, in the phosphoric acid fuel cell, the electrochemical reaction by the fuel gas, the oxidant gas, and the phosphoric acid solution proceeds through the electrolyte layer 14, and the power generation operation is performed. The direct current generated by the battery stack portion 11 is taken out by the output terminals 95a and 95b of the upper and lower fastening plates 91a and 91b, is AC converted by an orthogonal transformation device (not shown), and is used as commercial power.

特開平４−２５９７５８号公報JP-A-4-259758

ところで、燃料電池は、その用途拡大に伴い、設置場所の自由度の拡大やコストの低減などの観点から、構成の簡素化が望まれている。燃料電池の構成の簡素化の一例としては、図１２に示すように、電池積層部１１の架台９７への設置構造を改良した例が検討されている。図１２に示す例では、架台９７の上面に設けられた取付け座１００に電池積層部１１を直接固定し、部品点数を削減している。 By the way, as the use of fuel cells expands, simplification of the configuration is desired from the viewpoint of increasing the degree of freedom of installation locations and reducing costs. As an example of simplification of the configuration of the fuel cell, an example in which the installation structure of the cell stacking portion 11 on the mount 97 is improved as shown in FIG. In the example shown in FIG. 12, the battery stack portion 11 is directly fixed to the mounting seat 100 provided on the upper surface of the mount 97 to reduce the number of parts.

一方、リン酸形燃料電池は、燃料電池の運転に伴う温度変化のために、リン酸液が膨張してその一部が電解質層１４から漏出する現象が発生する。このため、リン酸形燃料電池では、漏出したリン酸液に対する電池積層部１１の電気的絶縁の確保及び構成部品の防食が必要となる。 On the other hand, in the phosphoric acid fuel cell, a phenomenon occurs in which the phosphoric acid solution expands and a part of the phosphoric acid leaks from the electrolyte layer 14 due to a temperature change accompanying the operation of the fuel cell. For this reason, in the phosphoric acid fuel cell, it is necessary to ensure the electrical insulation of the battery stack portion 11 against the leaked phosphoric acid solution and to prevent corrosion of the components.

図１２に示すリン酸形燃料電池では、電池積層部１１から漏出したリン酸液は、流路Ｌ３を伝って締付板９１ａの上面に滞留する。締付板９１ａの上面に滞留したリン酸液は、締付板９１ａの貫通孔と絶縁カラー９３ａとの間を介する流路Ｌ４及び締付板９１ａの外周を介する流路Ｌ５を伝って流下する。締付板９１ａの下面に流下したリン酸液は、絶縁カラー９３ａの側面を伝って取付け座１００に流下する。このため、漏出したリン酸液により、絶縁カラー９３ａの沿面絶縁が破壊される現象が発生する。沿面絶縁が破壊された場合、出力端子９５ａと架台９７との間で電気的に短絡することにより地絡検出リレー９９に電流が流れるために発電停止し運転不能となる。 In the phosphoric acid fuel cell shown in FIG. 12, the phosphoric acid solution leaked from the cell stack portion 11 stays on the upper surface of the fastening plate 91a through the flow path L3. The phosphoric acid solution staying on the upper surface of the clamping plate 91a flows down through the flow path L4 passing between the through hole of the clamping plate 91a and the insulating collar 93a and the flow path L5 passing through the outer periphery of the clamping plate 91a. . The phosphoric acid solution that has flowed down to the lower surface of the clamping plate 91a flows down to the mounting seat 100 along the side surface of the insulating collar 93a. For this reason, a phenomenon that the creeping insulation of the insulating collar 93a is broken by the leaked phosphoric acid solution. When the creeping insulation is broken, an electric short circuit between the output terminal 95a and the gantry 97 causes a current to flow through the ground fault detection relay 99, so that the power generation is stopped and the operation becomes impossible.

これに対し、リン酸液による電気的短絡を防ぐため、特許文献１記載の燃料電池では、下部の出力端子９５ａの電位をアースと同電位とすることにより、リン酸液の漏出により、電気的絶縁が破壊しても短絡電流が流れないように結線することが提案されている。 On the other hand, in order to prevent an electrical short circuit due to the phosphoric acid solution, in the fuel cell described in Patent Document 1, the electric potential of the lower output terminal 95a is set to the same potential as that of the ground so It has been proposed to connect so that a short-circuit current does not flow even when insulation is broken.

しかしながら、下部の出力端子９５ａの電位をアースと同電位とした場合、異常現象である燃料電池スタックの絶縁破壊を検出できず、そのまま運転維持されて燃料電池の出力損失が生じる品質上の問題がある。また、この場合には、中間電位で接地した場合と比較し、地絡箇所により大きな電流が流れ、燃料電池の損傷又は燃料電池が運転不能に陥る危険性があり、安全上でも問題があった。このように、燃料電池の構成の簡素化と燃料電池の信頼性の確保とを共に実現することは困難であった。 However, when the potential of the lower output terminal 95a is set to the same potential as that of the ground, it is impossible to detect an abnormal breakdown of the fuel cell stack, and there is a quality problem that the operation is maintained as it is and the output loss of the fuel cell occurs. is there. Also, in this case, compared to the case of grounding at an intermediate potential, a large current flows through the ground fault location, and there is a risk that the fuel cell may be damaged or the fuel cell may become inoperable. . Thus, it has been difficult to achieve both simplification of the configuration of the fuel cell and ensuring the reliability of the fuel cell.

本発明は、かかる点に鑑みてなされたものであり、構成を簡素化でき、しかも電気的短絡による出力損失及び燃料電池の損傷がなく、信頼性が高い燃料電池を提供することを目的とする。 The present invention has been made in view of such points, and an object of the present invention is to provide a highly reliable fuel cell that can simplify the configuration and that is free from output loss and damage to the fuel cell due to an electrical short circuit. .

本発明の燃料電池は、リン酸液を含浸した電解質層と当該電解質層の両側に配置された一対の燃料極及び酸化剤極とを備える単電池が積層された電池積層部と、前記電池積層部を固定する取付け座を備えた架台と、前記電池積層部の積層方向の下面側に配置され、貫通孔を有する第１締付板と、前記第１締付板との間で前記電池積層部を挟むように、前記電池積層部の積層方向の上面側に配置された第２締付板と、前記第１締付板と前記第２締付板との間に張架され、前記第１締付板の貫通孔から前記架台側へ貫通した先端部が前記取付け座に固定され、前記第１及び第２締付板間を加圧締付けする締付棒と、前記第１締付板と前記取付け座との間に介在し、前記締付棒が貫通した絶縁部材と、前記第１締付板の上面に漏出した前記リン酸液が前記貫通孔と前記絶縁部材との間の隙間から前記絶縁部材の外周部に漏出することを阻止する漏出阻止構造と、を具備し、前記漏出阻止構造は、前記第１締付板の貫通孔又は貫通孔近傍部位と対向する絶縁部材との間に設けられたＯリングであることを特徴とする。 The fuel cell of the present invention includes a battery stack portion in which unit cells each including an electrolyte layer impregnated with a phosphoric acid solution and a pair of fuel electrode and oxidant electrode disposed on both sides of the electrolyte layer are stacked, and the battery stack The battery stack between the first mounting plate having a mounting base for fixing the mounting portion, a first fastening plate disposed on the lower surface side in the stacking direction of the battery stacking portion and having a through hole, and the first fastening plate A second fastening plate disposed on the upper surface side in the stacking direction of the battery stacking portion, and sandwiched between the first fastening plate and the second fastening plate so as to sandwich the portion, A front end portion penetrating from the through hole of one fastening plate to the mount side is fixed to the mounting seat, and a fastening rod for pressure-tightening between the first and second fastening plates, and the first fastening plate wherein interposed between the mounting seat, and an insulating member which rod the tightening penetrates, the phosphoric acid solution leaked into the upper surface of plate with the first tightening and Anda leakage preventing structure for preventing the leakage from the gap on the outer periphery of the insulating member between the insulating member and the through hole, the leakage preventing structure has a through-hole of plate with the first fastening Or it is an O-ring provided between the through-hole vicinity site | part and the insulating member which opposes, It is characterized by the above-mentioned.

この構成によれば、燃料電池の発電動作に伴い、電池積層部から外部に漏出したリン酸液が絶縁部材の外周面に接触することなく滴下されるので、絶縁部材の沿面絶縁を保護することができる。これにより、燃料電池の電気的短絡による出力損失及び燃料電池本体の損傷を抑制することができ、信頼性が高い燃料電池を実現することができる。また、締付手段により電池積層部の加圧締付と電池積層部の固定とを共に行うことができるので、燃料電池の固定に用いる部品数を削減することができ、燃料電池の構成の簡素化及びコストの削減を実現できる。更に、貫通孔又は貫通孔近傍部位と対向する絶縁部材との間に設けられたＯリングにより、電池積層部から外部に漏出したリン酸液の第１締付板の貫通孔と絶縁部材との間からの漏出を抑止できるので、絶縁部材の沿面絶縁の破壊を抑制することができる。このため、燃料電池の電気的短絡を抑制でき、出力損失及び燃料電池本体の損傷を抑制することができる。 According to this configuration, the phosphoric acid solution leaked to the outside from the cell stack portion is dropped without contacting the outer peripheral surface of the insulating member during the power generation operation of the fuel cell, so that the creeping insulation of the insulating member is protected. Can do. As a result, output loss and fuel cell main body damage due to an electrical short circuit of the fuel cell can be suppressed, and a highly reliable fuel cell can be realized. In addition, the pressure-clamping of the battery stacking part and the fixing of the battery stacking part can be performed together by the fastening means, so that the number of parts used for fixing the fuel cell can be reduced, and the configuration of the fuel cell is simplified. And cost reduction can be realized. Furthermore, the O-ring provided between the through-hole or the vicinity of the through-hole and the insulating member facing the through-hole of the first fastening plate of the phosphoric acid solution leaked to the outside from the battery stack portion and the insulating member Since leakage from the gap can be suppressed, the breakage of the creeping insulation of the insulating member can be suppressed. For this reason, an electrical short circuit of the fuel cell can be suppressed, and output loss and damage to the fuel cell main body can be suppressed.

また本発明の燃料電池は、リン酸液を含浸した電解質層と当該電解質層の両側に配置された一対の燃料極及び酸化剤極とを備える単電池が積層された電池積層部と、前記電池積層部を固定する取付け座を備えた架台と、前記電池積層部の積層方向の下面側に配置され、貫通孔を有する第１締付板と、前記第１締付板との間で前記電池積層部を挟むように、前記電池積層部の積層方向の上面側に配置された第２締付板と、前記第１締付板と前記第２締付板との間に張架され、前記第１締付板の貫通孔から前記架台側へ貫通した先端部が前記取付け座に固定され、前記第１及び第２締付板間を加圧締付けする締付棒と、前記第１締付板と前記取付け座との間に介在し、前記締付棒が貫通した絶縁部材と、前記第１締付板の上面に漏出した前記リン酸液が前記貫通孔と前記絶縁部材との間の隙間から前記絶縁部材の外周部に漏出することを阻止する漏出阻止構造と、を具備し、前記漏出阻止構造は、前記第１締付板の下面と前記絶縁部材との当接面に設けられた複数の溝であることを特徴とする。 The fuel cell of the present invention includes a battery stack portion in which unit cells each including an electrolyte layer impregnated with a phosphoric acid solution and a pair of fuel electrode and oxidant electrode disposed on both sides of the electrolyte layer are stacked; Between the pedestal provided with a mounting seat for fixing the stacking portion, the first fastening plate disposed on the lower surface side in the stacking direction of the battery stacking portion and having a through hole, and the first fastening plate A second clamping plate disposed on the upper surface side in the stacking direction of the battery stacking part so as to sandwich the stacking part, and is stretched between the first clamping plate and the second clamping plate, A distal end portion penetrating from the through hole of the first fastening plate to the mount side is fixed to the mounting seat, and a fastening rod for pressure-tightening between the first and second fastening plates, and the first fastening An insulating member interposed between the plate and the mounting seat and through which the clamping rod penetrates, and the phosphorus leaked to the upper surface of the first clamping plate Liquid is provided with a leakage preventing structure for preventing the leakage from the gap on the outer periphery of the insulating member between the insulating member and the through hole, the leakage preventing structure plate with the first fastening It is a plurality of grooves provided on the contact surface between the lower surface and the insulating member.

この構成によれば、第１締付板の下面と絶縁部材との当接面に設けられた複数の溝により、電池積層部から外部に漏出したリン酸液の第１締付板の貫通孔と絶縁部材との間からの漏出を抑止できるので、絶縁部材の沿面絶縁の破壊を抑制することができる。このため、燃料電池の電気的短絡を抑制でき、出力損失及び燃料電池本体の損傷を抑制することができる。 According to this configuration, the through hole of the first fastening plate of the phosphoric acid solution leaked to the outside from the battery stack portion by the plurality of grooves provided in the contact surface between the lower surface of the first fastening plate and the insulating member Since leakage from between the insulating member and the insulating member can be suppressed, the breakage of the creeping insulation of the insulating member can be suppressed. For this reason, an electrical short circuit of the fuel cell can be suppressed, and output loss and damage to the fuel cell main body can be suppressed.

また本発明の燃料電池は、リン酸液を含浸した電解質層と当該電解質層の両側に配置された一対の燃料極及び酸化剤極とを備える単電池が積層された電池積層部と、前記電池積層部を固定する取付け座を備えた架台と、前記電池積層部の積層方向の下面側に配置され、貫通孔を有する第１締付板と、前記第１締付板との間で前記電池積層部を挟むように、前記電池積層部の積層方向の上面側に配置された第２締付板と、前記第１締付板と前記第２締付板との間に張架され、前記第１締付板の貫通孔から前記架台側へ貫通した先端部が前記取付け座に固定され、前記第１及び第２締付板間を加圧締付けする締付棒と、前記第１締付板と前記取付け座との間に介在し、前記締付棒が貫通した絶縁部材と、前記第１締付板の上面に漏出した前記リン酸液が前記貫通孔と前記絶縁部材との間の隙間から前記絶縁部材の外周部に漏出することを阻止する漏出阻止構造と、を具備し、前記絶縁部材は、前記第１締付板の貫通孔の直径よりも径が小さい小径部先端が、前記貫通孔から前記第１締付板の上面側に突出しており、前記漏出阻止構造は、前記絶縁部材の小径部の突出部に断面Ｖ字形状のリップ部を有するＶリングが嵌め込まれ、第１締付板の上面側に位置するリップ部を当該第１締付板の上面に加圧接触させたことを特徴とする。 The fuel cell of the present invention includes a battery stack portion in which unit cells each including an electrolyte layer impregnated with a phosphoric acid solution and a pair of fuel electrode and oxidant electrode disposed on both sides of the electrolyte layer are stacked; Between the pedestal provided with a mounting seat for fixing the stacking portion, the first fastening plate disposed on the lower surface side in the stacking direction of the battery stacking portion and having a through hole, and the first fastening plate A second clamping plate disposed on the upper surface side in the stacking direction of the battery stacking part so as to sandwich the stacking part, and is stretched between the first clamping plate and the second clamping plate, A distal end portion penetrating from the through hole of the first fastening plate to the mount side is fixed to the mounting seat, and a fastening rod for pressure-tightening between the first and second fastening plates, and the first fastening An insulating member interposed between the plate and the mounting seat and through which the clamping rod penetrates, and the phosphorus leaked to the upper surface of the first clamping plate Liquid is provided with a leakage preventing structure for preventing the leakage from the gap on the outer periphery of the insulating member between said insulating member and said through hole, said insulating member, through the plate with the first fastening The tip of the small diameter portion having a diameter smaller than the diameter of the hole protrudes from the through hole to the upper surface side of the first fastening plate, and the leakage prevention structure has a V-shaped cross section at the small diameter portion of the insulating member. A V-ring having a shaped lip portion is fitted, and the lip portion located on the upper surface side of the first fastening plate is brought into pressure contact with the upper surface of the first fastening plate.

この構成によれば、貫通孔から第１締付板の上面側に突出した絶縁部材の小径部の突出部に嵌め込まれ、リップ部が第１締付板の上面と加圧接触するＶリングにより、電池積層部から外部に漏出したリン酸液の第１締付板の貫通孔内への流入を抑制できるので、絶縁部材の沿面絶縁の破壊を抑制することができる。このため、燃料電池の電気的短絡を抑制でき、出力損失及び燃料電池本体の損傷を抑制することができる。また、Ｖリングの取付け位置の調整により、リップ部と第１締付板との間の加圧接触を調整できるので、電解質液の第１締付板の貫通孔内への流入を効果的に抑制できる。
また本発明は、上記燃料電池において、前記第１締結板の下面において前記第１締結板の前記貫通孔を囲む領域に形成され、外縁部が前記貫通孔の外周よりも外側となるように下方に向けて突出した笠部を更に具備することを特徴とする。 According to this configuration, the V-ring is fitted into the protruding portion of the small diameter portion of the insulating member protruding from the through hole to the upper surface side of the first clamping plate, and the lip portion is in pressure contact with the upper surface of the first clamping plate. Since the phosphoric acid solution leaked to the outside from the battery stack portion can be suppressed from flowing into the through hole of the first fastening plate, the breakage of the creeping insulation of the insulating member can be suppressed. For this reason, an electrical short circuit of the fuel cell can be suppressed, and output loss and damage to the fuel cell main body can be suppressed. In addition, since the pressure contact between the lip portion and the first fastening plate can be adjusted by adjusting the mounting position of the V-ring, the electrolyte solution can effectively flow into the through hole of the first fastening plate. Can be suppressed.
Further, the present invention provides the above fuel cell, wherein the lower surface of the first fastening plate is formed in a region surrounding the through hole of the first fastening plate so that the outer edge portion is outside the outer periphery of the through hole. It further comprises a cap portion protruding toward the head.

本発明によれば、構成を簡素化でき、しかも電気的短絡による出力損失及び燃料電池の損傷がなく、信頼性が高い燃料電池を提供することができる。 ADVANTAGE OF THE INVENTION According to this invention, a structure can be simplified and there can be provided the fuel cell with high reliability without the output loss and damage of a fuel cell by an electrical short circuit.

本発明の実施の形態に係る燃料電池の模式的な斜視図である。1 is a schematic perspective view of a fuel cell according to an embodiment of the present invention. 本発明の実施の形態に係る燃料電池の断面図である。1 is a cross-sectional view of a fuel cell according to an embodiment of the present invention. 本発明の第１の実施の形態に係る燃料電池の部分断面拡大図である。1 is an enlarged partial cross-sectional view of a fuel cell according to a first embodiment of the present invention. 本発明の第２の実施の形態に係る燃料電池の部分断面拡大図である。FIG. 5 is an enlarged partial cross-sectional view of a fuel cell according to a second embodiment of the present invention. 本発明の第２の実施の形態に係る燃料電池の他の一例の部分断面拡大図である。It is a partial cross-section enlarged view of another example of the fuel cell according to the second embodiment of the present invention. 本発明の第３の実施の形態に係る燃料電池の部分断面拡大図である。FIG. 6 is an enlarged partial cross-sectional view of a fuel cell according to a third embodiment of the present invention. 本発明の第４の実施の形態に係る燃料電池の部分断面拡大図である。FIG. 6 is an enlarged partial cross-sectional view of a fuel cell according to a fourth embodiment of the present invention. 本発明の第４の実施の形態に係る燃料電池の他の一例の部分断面拡大図である。It is a partial cross-section enlarged view of another example of the fuel cell according to the fourth embodiment of the present invention. 一般的な燃料電池の単電池の積層構造を示す図である。It is a figure which shows the laminated structure of the cell of a common fuel cell. 一般的な燃料電池の模式的な断面図である。It is typical sectional drawing of a common fuel cell. 一般的な燃料電池の模式的な回路図である。It is a typical circuit diagram of a general fuel cell. 構成を簡素化した燃料電池の部分断面拡大図である。It is the partial cross-section enlarged view of the fuel cell which simplified the structure.

以下、本発明の実施の形態について、添付図面を参照して詳細に説明する。尚、以下の説明では、図９〜図１１に示したリン酸形燃料電池と同一構成の部分には、同一の符号を付して説明を省略し、本発明の実施の形態に係る燃料電池と一般的なリン酸形燃料電池との相違点を中心に説明する。 Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same components as those in the phosphoric acid fuel cell shown in FIGS. 9 to 11 are denoted by the same reference numerals and the description thereof is omitted, and the fuel cell according to the embodiment of the present invention is omitted. The difference between the fuel cell and a general phosphoric acid fuel cell will be mainly described.

（第１の実施の形態）
図１は、本発明の実施の形態に係る燃料電池１の模式的な斜視図である。本実施の形態に係る燃料電池１は、リン酸形燃料電池の単電池１２が複数積層された電池積層部１１と、当該電池積層部１１の下面に配置され、電池積層部１１を固定する架台２０とを主に備える。尚、図１においては、一つの単電池１２のみ図示し、他の単電池１２については符号を省略している。 (First embodiment)
FIG. 1 is a schematic perspective view of a fuel cell 1 according to an embodiment of the present invention. The fuel cell 1 according to the present embodiment includes a battery stack portion 11 in which a plurality of single cells 12 of a phosphoric acid fuel cell are stacked, and a frame that is disposed on the lower surface of the battery stack portion 11 and fixes the battery stack portion 11. 20 is mainly provided. In FIG. 1, only one unit cell 12 is shown, and the other unit cells 12 are omitted from the reference numerals.

電池積層部１１は、複数の単電池１２が上下方向に積層されて構成され、略矩形形状の上面及び下面を有する。電池積層部１１の下面には、平面視において、電池積層部１１の下面から４隅が突出するように略矩形形状の下部締付板２１が配置されている。一方、電池積層部１１の上面には、下部締付板２１と対応した略矩形形状を有する上部締付板２２が配置されている。電池積層部１１の上下の面から突出した下部締付板２１及び上部締付板２２の４隅には、それぞれ対向する位置に貫通孔が設けられている。この対向する４隅の貫通孔には、円柱形状に形成され両端にらせん状のネジ山を有する４本の締付スタッド２３ａ〜２３ｄが挿通されている。 The battery stack portion 11 is configured by stacking a plurality of unit cells 12 in the vertical direction, and has a substantially rectangular upper and lower surfaces. A substantially rectangular lower fastening plate 21 is disposed on the lower surface of the battery stack 11 so that the four corners protrude from the lower surface of the battery stack 11 in plan view. On the other hand, an upper clamping plate 22 having a substantially rectangular shape corresponding to the lower clamping plate 21 is disposed on the upper surface of the battery stack 11. Through holes are provided at positions facing the four corners of the lower fastening plate 21 and the upper fastening plate 22 that protrude from the upper and lower surfaces of the battery stack 11. Four fastening studs 23a to 23d, which are formed in a columnar shape and have spiral threads on both ends, are inserted into the through holes at the four corners facing each other.

図２は、図１に示した燃料電池１の側面模式図である。図２に示すように、下部締付板２１の下面側には、電池積層部１１を固定する取付け座２４ａが設けられた架台２０が配置されている。架台２０は、取付け座２４ａが絶縁カラー２５ａを介して下部締付板２１の貫通孔と重なるように配置される。下部締付板２１の貫通孔に挿通された締付スタッド２３ａの下端は、絶縁カラー２５ａを貫通して架台２０の取付け座２４ａから突出するように配置される。締付スタッド２３ａの下端には、取付け座２４ａと下部締付板２１との間を締付するナット２６ａが締結されている。一方、上部締付板２２に挿通された締付スタッド２３ａの上端には、絶縁カラー２７ａを介して上部締付板２２と下部締付板２１との間を締付するナット２８ａが締結されている。 FIG. 2 is a schematic side view of the fuel cell 1 shown in FIG. As shown in FIG. 2, on the lower surface side of the lower fastening plate 21, a gantry 20 provided with a mounting seat 24 a that fixes the battery stack 11 is disposed. The gantry 20 is arranged so that the mounting seat 24a overlaps the through hole of the lower fastening plate 21 via the insulating collar 25a. The lower end of the fastening stud 23 a inserted through the through hole of the lower fastening plate 21 is arranged so as to penetrate the insulating collar 25 a and protrude from the mounting seat 24 a of the gantry 20. A nut 26a for fastening between the mounting seat 24a and the lower fastening plate 21 is fastened to the lower end of the fastening stud 23a. On the other hand, a nut 28a for fastening between the upper fastening plate 22 and the lower fastening plate 21 is fastened to the upper end of the fastening stud 23a inserted through the upper fastening plate 22 via an insulating collar 27a. Yes.

すなわち、本実施の形態においては、下部締付板２１と上部締付板２２との間に張架される締付スタッド２３ａにより、下部締付板２１及び上部締付板２２を介した電池積層部１１の加圧締付と電池積層部１１の架台２０への固定とを共に行うことにより、絶縁支持碍子などを用いることなく電池積層部１１を直接架台２０へ固定している。これにより、部品点数の削減が可能となり、燃料電池の構造を簡略化することができ、燃料電池１の小型化及びコスト削減が可能となる。下部締付板２１及び上部締付板２２には、それぞれ発電された直流電流を取り出す出力端子２９ａ、２９ｂが設けられている。尚、以上の説明では、締付スタッド２３ａを例に燃料電池１の架台２０への固定について説明したが、他の締付スタッド２３ｂ〜２３ｄも同様に構成されている。 That is, in the present embodiment, battery stacking via the lower clamping plate 21 and the upper clamping plate 22 by the clamping stud 23a stretched between the lower clamping plate 21 and the upper clamping plate 22 is performed. By performing both the pressure tightening of the part 11 and the fixing of the battery stacking part 11 to the gantry 20, the battery stacking part 11 is directly fixed to the pedestal 20 without using an insulating support insulator or the like. Thereby, the number of parts can be reduced, the structure of the fuel cell can be simplified, and the fuel cell 1 can be reduced in size and cost. The lower fastening plate 21 and the upper fastening plate 22 are provided with output terminals 29a and 29b for taking out the generated direct current, respectively. In the above description, the fastening stud 23a is used as an example to describe the fixing of the fuel cell 1 to the gantry 20, but the other fastening studs 23b to 23d are similarly configured.

図３は、図２に示した燃料電池１の断面図の部分拡大図である。尚、図３では、出力端子２９ａは省略している。図３に示すように、下部締付板２１の貫通孔より小さい外径を有し、貫通孔内に挿入される小径部と、小径部より相対的に外径が大きく形成され、下部締付板２１下面の開口端部と取付け座２４ａとの間に配置される大径部とを絶縁カラー２５ａは備える。絶縁カラー２５ａの外周面の大径部と小径部との間には、大径部と小径部の径の差に応じた段差が形成されている。この絶縁カラー２５ａの段差の上面が下部締付板２１下面の貫通孔の開口端部と当接する当接面４０ａとなる。絶縁カラー２５ａの小径部は、下部締付板２１の貫通孔と対向するように貫通孔内に沿って上方に延在され、上端が下部締付板２１の上面から突出するように配置されている。 3 is a partially enlarged view of the cross-sectional view of the fuel cell 1 shown in FIG. In FIG. 3, the output terminal 29a is omitted. As shown in FIG. 3, the lower fastening plate 21 has an outer diameter smaller than the through hole, a small diameter portion inserted into the through hole, and an outer diameter relatively larger than the small diameter portion. The insulating collar 25a includes a large-diameter portion disposed between the opening end portion on the lower surface of the plate 21 and the mounting seat 24a. A step corresponding to the difference in diameter between the large diameter portion and the small diameter portion is formed between the large diameter portion and the small diameter portion of the outer peripheral surface of the insulating collar 25a. The upper surface of the step of the insulating collar 25a serves as a contact surface 40a that contacts the open end of the through hole in the lower surface of the lower fastening plate 21. The small-diameter portion of the insulating collar 25 a extends upward along the through hole so as to face the through hole of the lower fastening plate 21, and is arranged so that the upper end protrudes from the upper surface of the lower fastening plate 21. Yes.

次に、本実施の形態に係る燃料電池１のリン酸液の漏出阻止構造について説明する。本実施の形態の形態に係る燃料電池１は、発電に伴って漏出したリン酸液が下部締付板２１の貫通孔と絶縁カラー２５ａとの間からの漏出を抑制する漏出阻止構造としての上部突出部３０を備える。上部突出部３０は、下部締付板２１上面の貫通孔を囲む周縁部に、下部締付板２１の上面から上方に向かって突出するように形成されている。本実施の形態では、この上部突出部３０により、下部締付板２１の上面に滞留したリン酸液の下部締付板２１の貫通孔内への流入を抑制し、下部締付板２１の貫通孔と絶縁カラー２５ａとの間からのリン酸液の漏出を抑制している。 Next, the leakage prevention structure of the phosphoric acid solution of the fuel cell 1 according to the present embodiment will be described. In the fuel cell 1 according to the present embodiment, the phosphoric acid solution leaked with power generation is an upper portion as a leakage prevention structure that suppresses leakage from between the through hole of the lower fastening plate 21 and the insulating collar 25a. A protrusion 30 is provided. The upper protrusion 30 is formed on the peripheral edge surrounding the through hole on the upper surface of the lower fastening plate 21 so as to protrude upward from the upper surface of the lower fastening plate 21. In the present embodiment, the upper protrusion 30 suppresses the inflow of the phosphoric acid solution staying on the upper surface of the lower fastening plate 21 into the through hole of the lower fastening plate 21, thereby penetrating the lower fastening plate 21. Leakage of the phosphoric acid solution from between the hole and the insulating collar 25a is suppressed.

尚、上部突出部３０は、下部締付板２１の上面において、リン酸液の貫通孔内への流入を抑制できる位置に設けられていればよく、必ずしも下部締付板２１の貫通孔の開口端部に対応した形状でなくともよい。例えば、下部締付板２１の貫通孔の開口部と同芯円状に形成されていてもよく、下部締付板２１の開口部の周囲に、略矩形形状に形成されていてもよい。また、上部突出部３０の形状は、リン酸液の貫通孔内への流入を抑制できる形状であれば特に限定されない。また、上部突出部の３０の形状は、下部締付板２１上面の主面に対して、高さ方向において所定の割合で傾斜が形成されていればよく、完全な階段形状を必要とするものではない。 The upper protrusion 30 may be provided on the upper surface of the lower fastening plate 21 at a position where the inflow of the phosphoric acid solution into the through hole can be suppressed, and the opening of the through hole of the lower fastening plate 21 is not necessarily required. The shape does not have to correspond to the end. For example, it may be formed concentrically with the opening of the through hole of the lower fastening plate 21, or may be formed in a substantially rectangular shape around the opening of the lower fastening plate 21. Moreover, the shape of the upper protrusion part 30 will not be specifically limited if it can suppress the inflow into the through-hole of a phosphoric acid liquid. Further, the shape of the upper protruding portion 30 is only required to be inclined at a predetermined ratio in the height direction with respect to the main surface of the upper surface of the lower fastening plate 21, and requires a complete step shape. is not.

下部締付板２１の下面には、下部締付板２１の上面から流下するリン酸液を、絶縁カラー２５ａとの接触を避けるように下方に滴下する笠部としての下部突出部３１が設けられている。下部突出部３１は、下部締付板２１の貫通孔を囲む領域に設けられ、下部締付板２１の下面から下方に向かって突出するように設けられている。また、下部突出部３１は、リン酸液の絶縁カラー２５ａへの付着を回避できるように、下部突出部３１の外縁部が絶縁カラー２５ａの大径部の外周面と所定の間隔を取るように離間して設けられている。本実施の形態では、この下部突出部３１により、下部締付板２１の上面から下部締付板２１の側面を伝って流下するリン酸液を誘導し、絶縁カラー２５ａと接触することなく滴下する。これにより、漏出したリン酸液の絶縁カラー２５ａの外周面に接触を抑制することができるので、燃料電池１の沿面絶縁の破壊を防止できる。 On the lower surface of the lower clamping plate 21, there is provided a lower protrusion 31 as a cap portion for dropping a phosphoric acid solution flowing down from the upper surface of the lower clamping plate 21 so as to avoid contact with the insulating collar 25a. ing. The lower protruding portion 31 is provided in a region surrounding the through hole of the lower fastening plate 21 and is provided so as to protrude downward from the lower surface of the lower fastening plate 21. Further, the lower protruding portion 31 is arranged such that the outer edge portion of the lower protruding portion 31 has a predetermined distance from the outer peripheral surface of the large-diameter portion of the insulating collar 25a so that the phosphoric acid solution can be prevented from adhering to the insulating collar 25a. They are spaced apart. In the present embodiment, the lower protrusion 31 induces the phosphoric acid solution flowing down from the upper surface of the lower fastening plate 21 along the side surface of the lower fastening plate 21 and drops it without contacting the insulating collar 25a. . Thereby, contact with the outer peripheral surface of the insulating collar 25a of the leaked phosphoric acid solution can be suppressed, so that breakage of the creeping insulation of the fuel cell 1 can be prevented.

尚、下部突出部３１の形状は、リン酸液の絶縁カラー２５ａへの接触を回避できるように誘導できる形状であれば、特に限定されない。例えば、下部突出部３１の形状は、下部締付板２１下面に対して、少なくとも下方に突出していればよく、完全な階段形状を必要とするものではない。また、下部突出部３１は、絶縁カラー２５ａと接触せずにリン酸液を滴下できれば絶縁カラー２５ａの外周縁部に形成されていなくともよく、絶縁カラー２５ａ〜２５ｄの外側を囲むように、略矩形形状に形成されていてもよい。 In addition, the shape of the lower protrusion part 31 will not be specifically limited if it is a shape which can be induced | guided | derived so that the contact to the insulating collar 25a of a phosphoric acid liquid can be avoided. For example, the shape of the lower protrusion 31 is not limited to a complete step shape as long as it protrudes at least downward relative to the lower surface of the lower fastening plate 21. Further, the lower protrusion 31 may not be formed on the outer peripheral edge of the insulating collar 25a as long as the phosphoric acid solution can be dropped without coming into contact with the insulating collar 25a, and is substantially formed so as to surround the outer sides of the insulating collars 25a to 25d. It may be formed in a rectangular shape.

次に、本実施の形態に係る燃料電池１におけるリン酸液の流路について説明する。電池積層部１１から漏出したリン酸液は、流路Ｌ１を伝って、電池積層部１１の側面から下部締付板２１の上面に向けて流下する。下部締付板２１の上面に流下したリン酸液は、下部締付板２１上面を下部締付板２１の端部へ向けて流れる。ここで、下部締付板２１の上面には、上部突出部３０が設けられているので、下部締付板２１の貫通孔へ流入せずに、下部締付板２１の端部から流路Ｌ２を伝って、下部締付板２１の下面側に向けて流下する。 Next, the flow path of the phosphoric acid solution in the fuel cell 1 according to the present embodiment will be described. The phosphoric acid solution leaked from the battery stack portion 11 flows along the flow path L <b> 1 and flows down from the side surface of the battery stack portion 11 toward the upper surface of the lower fastening plate 21. The phosphoric acid solution that has flowed down to the upper surface of the lower clamping plate 21 flows toward the end of the lower clamping plate 21 on the upper surface of the lower clamping plate 21. Here, since the upper protrusion 30 is provided on the upper surface of the lower fastening plate 21, the flow path L2 does not flow into the through hole of the lower fastening plate 21 and flows from the end of the lower fastening plate 21. Then, it flows down toward the lower surface side of the lower fastening plate 21.

下部締付板２１の下面側に流下したリン酸液は、下部締付板２１下面の下部突出部３１の先端に向けて流下し、所定の液量のリン酸液が溜まった後に、重力に従って、絶縁カラー２５ａに接触することなく滴下する。ここで、下部突出部３１がない場合、リン酸液の一部は、下部締付板２１の下面を伝って絶縁カラー２５ａの側面から流下し、絶縁カラー２５ａの沿面絶縁が破壊される。これに対し、本実施の形態では、下部締付板２１下面に下部突出部３１が設けられているので、リン酸液が下部突出部３１の先端部に誘導されて絶縁カラー２５ａへの接触を回避することができ、燃料電池１の沿面絶縁の破壊を防止することができる。 The phosphoric acid solution that has flowed down to the lower surface side of the lower clamping plate 21 flows toward the tip of the lower protrusion 31 on the lower surface of the lower clamping plate 21, and after a predetermined amount of phosphoric acid solution has accumulated, according to gravity. Then, it is dropped without contacting the insulating collar 25a. Here, when there is no lower protrusion 31, a part of the phosphoric acid solution flows down from the side surface of the insulating collar 25a along the lower surface of the lower fastening plate 21, and the creeping insulation of the insulating collar 25a is destroyed. On the other hand, in the present embodiment, since the lower protrusion 31 is provided on the lower surface of the lower fastening plate 21, the phosphoric acid solution is guided to the tip of the lower protrusion 31 to contact the insulating collar 25a. This can be avoided, and the breakage of the creeping insulation of the fuel cell 1 can be prevented.

以上説明したように、本実施の形態によれば、下部締付板２１にリン酸液の漏出阻止構造としての上部突出部３０とリン酸液を滴下する下部突出部３１とを設けることにより、絶縁カラー２５ａへのリン酸液の接触を回避することができるので、燃料電池１の沿面絶縁の破壊を防止することができる。これにより、電気的短絡による出力電圧の低下及び燃料電池の損傷を抑制することができ、長期間に亘って安定して運転可能な信頼性の高い燃料電池を実現できる。また、締付けスタッド２３ａ〜２３ｄにより、電池積層部１１の締付けによるガスシールと電池積層部１１の架台２０への固定とを共に行うことができるので、構成部品を削減することができる。 As described above, according to the present embodiment, by providing the lower fastening plate 21 with the upper protrusion 30 as the phosphate liquid leakage prevention structure and the lower protrusion 31 for dropping the phosphoric acid solution, Since the contact of the phosphoric acid solution with the insulating collar 25a can be avoided, the breakage of the creeping insulation of the fuel cell 1 can be prevented. As a result, a decrease in output voltage due to an electrical short circuit and damage to the fuel cell can be suppressed, and a highly reliable fuel cell that can be stably operated over a long period of time can be realized. In addition, the fastening studs 23a to 23d can perform both gas sealing by fastening the battery stacking portion 11 and fixation of the battery stacking portion 11 to the gantry 20, so that the number of components can be reduced.

（第２の実施の形態）
次に、図４、図５を参照して本発明の第２の実施の形態について説明する。
本実施の形態に係る燃料電池２は、リン酸液の漏出阻止構造として、Ｏリング３２を用いたものである。以下の説明においては、燃料電池１との相違点を中心に説明し、燃料電池１と同一の部分については、同一の符号を付し、説明を省略する。 (Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS.
The fuel cell 2 according to the present embodiment uses an O-ring 32 as a phosphoric acid liquid leakage prevention structure. In the following description, differences from the fuel cell 1 will be mainly described, and the same parts as those of the fuel cell 1 will be denoted by the same reference numerals and description thereof will be omitted.

図４は、本実施の形態に係る燃料電池２の下部締付板２１の貫通孔及び締付スタッド２３ａの拡大断面図である。図４に示すように、本実施の形態では、下部締付板２１の上面を平面構造としている。下部締付板２１の貫通孔の内周面には、内周面の周方向に延在する矩形形状の溝が形成され、この溝の中に弾性部材としてのＯリング３２が配置されている。Ｏリング３２は、下部締付板２１の内周面と絶縁カラー２５ａの小径部の外周面との間をシールするように配置されている。 FIG. 4 is an enlarged cross-sectional view of the through hole of the lower fastening plate 21 and the fastening stud 23a of the fuel cell 2 according to the present embodiment. As shown in FIG. 4, in the present embodiment, the upper surface of the lower fastening plate 21 has a planar structure. A rectangular groove extending in the circumferential direction of the inner peripheral surface is formed on the inner peripheral surface of the through hole of the lower fastening plate 21, and an O-ring 32 as an elastic member is disposed in the groove. . The O-ring 32 is disposed so as to seal between the inner peripheral surface of the lower fastening plate 21 and the outer peripheral surface of the small-diameter portion of the insulating collar 25a.

尚、本実施の形態では、Ｏリング３２の配置は、下部締付板２１の貫通孔の内周面に限定されず、例えば、下部締付板２１下面の開口端部と絶縁カラー２５ａとの当接面４０ａに配置する構成としてもよい。図５に示す例では、絶縁カラー２５ａの当接面４０ａに締付スタッド２３ａを中心とした同芯円状の略矩形状の溝を形成し、この溝の中にＯリング３２を配置している。このようにＯリング３２を配置することにより、下部締付板２１下面の開口端部と絶縁カラー２５ａとの間に生じる面圧によってリン酸液を水密シールできるので、燃料電池２の沿面絶縁の破壊を防止することができる。尚、Ｏリング３２は、下部締付板２１の貫通孔又は貫通孔近傍部位と、対向する絶縁部材との間に設けられていればよい。また、Ｏリング３２が配置される溝は、下部締付板２１側に形成されていてもよく、絶縁カラー２５ａ側に形成されていてもよい。 In the present embodiment, the arrangement of the O-ring 32 is not limited to the inner peripheral surface of the through hole of the lower fastening plate 21. For example, the opening end portion of the lower surface of the lower fastening plate 21 and the insulating collar 25a are arranged. It is good also as a structure arrange | positioned on the contact surface 40a. In the example shown in FIG. 5, a concentric circular substantially rectangular groove centering on the fastening stud 23a is formed on the contact surface 40a of the insulating collar 25a, and an O-ring 32 is disposed in the groove. Yes. By disposing the O-ring 32 in this manner, the phosphoric acid solution can be watertightly sealed by the surface pressure generated between the opening end portion of the lower surface of the lower fastening plate 21 and the insulating collar 25a. Destruction can be prevented. In addition, the O-ring 32 should just be provided between the through-hole of the lower clamping plate 21, or the site | part vicinity of a through-hole, and the opposing insulating member. Further, the groove in which the O-ring 32 is disposed may be formed on the lower fastening plate 21 side, or may be formed on the insulating collar 25a side.

Ｏリング３２の材質としては、弾性力によりリン酸液を遮断でき、かつリン酸に対して耐腐食性があるものであれば特に限定されないが、フッ素ゴム、ブチルゴム、エチレンプロピレンゴム、クロロスルフォン化ポリエチレンゴム、などのゴム材料を用いることができる。これらの中でも、リン酸に対する耐腐食性が強いフッ素ゴムが特に好ましい。尚、Ｏリング３２としては、市販のものを用いることができる。 The material of the O-ring 32 is not particularly limited as long as it can block the phosphoric acid solution by elastic force and has corrosion resistance to phosphoric acid, but is not limited to fluorine rubber, butyl rubber, ethylene propylene rubber, chlorosulfonated A rubber material such as polyethylene rubber can be used. Among these, fluororubber having strong corrosion resistance against phosphoric acid is particularly preferable. A commercially available O-ring 32 can be used.

次に、本実施の形態でのリン酸液の流路について説明する。本実施の形態では、下部締付板２１の上面に流下したリン酸液は、下部締付板２１の貫通孔内に流入する。ここで、下部締付板２１の貫通孔内には、Ｏリング３２が設けられているので、貫通孔内に流入したリン酸液は、Ｏリング３２の弾性力によって貫通孔内で水密シールされる。このため、下部締付板２１の貫通孔と絶縁カラー２５ａとの間からのリン酸液の漏出を抑止することができる。 Next, the flow path of the phosphoric acid solution in the present embodiment will be described. In the present embodiment, the phosphoric acid solution that has flowed down to the upper surface of the lower fastening plate 21 flows into the through hole of the lower fastening plate 21. Here, since the O-ring 32 is provided in the through hole of the lower fastening plate 21, the phosphoric acid solution that has flowed into the through hole is water-tightly sealed in the through hole by the elastic force of the O-ring 32. The For this reason, leakage of the phosphoric acid solution from between the through hole of the lower fastening plate 21 and the insulating collar 25a can be suppressed.

このように、本実施の形態に係る燃料電池２によれば、電池積層部１１の側面から流下したリン酸液は、滴下経路Ｌ１を伝わり下部締付板２１の表面まで流下し、一旦は下部締付板２１の貫通孔に流入する。貫通孔に流入したリン酸液は、下部締付板２１の貫通孔内のＯリング３２によりシールされ、貫通孔を迂回して下部締付板２１の外周を伝わり下部突出部３１より滴下される。これにより、絶縁カラー２５ａ外周面へのリン酸液の接触を回避できるので、燃料電池２の沿面絶縁の破壊を抑制することができる。 Thus, according to the fuel cell 2 according to the present embodiment, the phosphoric acid solution that has flowed down from the side surface of the cell stack portion 11 flows down to the surface of the lower fastening plate 21 through the dropping path L1, and is once in the lower portion. It flows into the through hole of the clamping plate 21. The phosphoric acid solution that has flowed into the through hole is sealed by the O-ring 32 in the through hole of the lower fastening plate 21, bypasses the through hole, travels around the outer periphery of the lower fastening plate 21, and is dropped from the lower protrusion 31. . Thereby, since the contact of the phosphoric acid solution to the outer peripheral surface of the insulating collar 25a can be avoided, the breakage of the creeping insulation of the fuel cell 2 can be suppressed.

（第３の実施の形態）
次に、図６を参照して、本発明の第３の実施の形態について説明する。
本実施の形態に係る燃料電池３は、リン酸液の漏出阻止構造として、絶縁カラー２５ａと下部締付板２１の開口端部との当接面４０ａに複数の溝（以下、複数の溝をラビリンス・シール溝３３ともいう）を設けたものである。以下の説明においては、燃料電池１との相違点を中心に説明し、燃料電池１と同一の部分については、同一の符号を付し、説明を省略する。 (Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG.
The fuel cell 3 according to the present embodiment has a plurality of grooves (hereinafter referred to as a plurality of grooves) on the contact surface 40a between the insulating collar 25a and the opening end of the lower fastening plate 21 as a phosphoric acid liquid leakage prevention structure. A labyrinth seal groove 33). In the following description, differences from the fuel cell 1 will be mainly described, and the same parts as those of the fuel cell 1 will be denoted by the same reference numerals and description thereof will be omitted.

図６は、本実施の形態に係る燃料電池３の下部締付板２１の貫通孔及び締付スタッド２３ａの拡大断面図である。図６に示すように、本実施の形態に係る燃料電池３では、絶縁カラー２５ａの下部締付板２１下面との当接面４０ａに、それぞれが独立した複数のＶ字溝によって構成されるラビリンス・シール溝３３が形成されている。このラビリンス・シール溝３３は、締付スタッド２３ａと同芯円状に形成されている。本実施の形態では、このラビリンス・シール溝３３により、下部締付板２１の貫通孔と絶縁カラー２５ａとの間からのリン酸液の漏出を抑止する。 FIG. 6 is an enlarged cross-sectional view of the through hole of the lower fastening plate 21 and the fastening stud 23a of the fuel cell 3 according to the present embodiment. As shown in FIG. 6, in the fuel cell 3 according to the present embodiment, the labyrinth constituted by a plurality of independent V-shaped grooves on the contact surface 40a of the insulating collar 25a with the lower surface of the lower fastening plate 21. A seal groove 33 is formed. The labyrinth seal groove 33 is formed concentrically with the fastening stud 23a. In the present embodiment, the labyrinth seal groove 33 prevents leakage of the phosphoric acid solution from between the through hole of the lower fastening plate 21 and the insulating collar 25a.

尚、ラビリンス・シール溝３３の形状としては、下部締付板２１の貫通孔内部に流入したリン酸液をシールできる形状であればＶ形状に限定されず、Ｕ字形状、矩形形状の溝などを用いてもよい。また、本実施の形態では、ラビリンス・シール溝３３が絶縁カラー２５ａに形成された例について説明したが、ラビリンス・シール溝３３は、下部締付板２１に形成してもよい。 The shape of the labyrinth seal groove 33 is not limited to the V shape as long as the phosphoric acid solution flowing into the through hole of the lower fastening plate 21 can be sealed. May be used. In the present embodiment, an example in which the labyrinth seal groove 33 is formed in the insulating collar 25 a has been described. However, the labyrinth seal groove 33 may be formed in the lower fastening plate 21.

次に、本実施の形態でのリン酸液の流路について説明する。本実施の形態では、電池積層部１１の側面から滴下したリン酸液は、滴下経路Ｌ１を伝わり下部締付板２１の上面を伝って、下部締付板２１の貫通孔内に流入する。貫通孔内に流入したリン酸液は、下部締付板２１の貫通孔内のラビリンス・シール溝３３の内側の溝から外側の溝に向けて徐々に浸透する。ここで、リン酸液は粘性が高く、表面張力が大きいので、ラビリンス・シール溝３３内でリン酸液の毛細管力によりシールされるラビリンス効果が発現する。このため、下部締付板２１の貫通孔と絶縁カラー２５ａとの間からのリン酸液の漏出を抑止することができる。 Next, the flow path of the phosphoric acid solution in the present embodiment will be described. In the present embodiment, the phosphoric acid solution dropped from the side surface of the battery stack portion 11 flows along the dropping path L <b> 1, the upper surface of the lower fastening plate 21, and flows into the through hole of the lower fastening plate 21. The phosphoric acid solution that has flowed into the through hole gradually permeates from the inner groove to the outer groove of the labyrinth seal groove 33 in the through hole of the lower fastening plate 21. Here, since the phosphoric acid solution has a high viscosity and a large surface tension, a labyrinth effect sealed in the labyrinth seal groove 33 by the capillary force of the phosphoric acid solution appears. For this reason, leakage of the phosphoric acid solution from between the through hole of the lower fastening plate 21 and the insulating collar 25a can be suppressed.

このように、本実施の形態に係る燃料電池３によれば、電池積層部１１の側面から流下したリン酸液は、滴下経路Ｌ１を伝わり下部締付板２１の表面まで流下し、一旦は下部締付板２１の貫通孔に流入する。下部締付板２１の貫通孔内のラビリンス・シール溝３３によりシールされ、貫通孔を迂回して下部締付板２１の外周を伝わり下部突出部３１より滴下される。これにより、絶縁カラー２５ａ外周面へのリン酸液の接触を回避できるので、リン酸液による燃料電池３の沿面絶縁の破壊を抑制することができる。 Thus, according to the fuel cell 3 according to the present embodiment, the phosphoric acid solution that has flowed down from the side surface of the cell stack portion 11 flows down to the surface of the lower fastening plate 21 through the dropping path L1, and is once in the lower portion. It flows into the through hole of the clamping plate 21. It is sealed by a labyrinth seal groove 33 in the through hole of the lower fastening plate 21, bypasses the through hole, travels along the outer periphery of the lower fastening plate 21, and is dropped from the lower protrusion 31. Thereby, since the contact of the phosphoric acid solution to the outer peripheral surface of the insulating collar 25a can be avoided, the breakage of the creeping insulation of the fuel cell 3 by the phosphoric acid solution can be suppressed.

特に、リン酸形の燃料電池では、電解質として高濃度のリン酸液を用いるので、リン酸液の粘性が高くなる。このため、本実施の形態に係る燃料電池３では、下部締付板２１の貫通孔内に内部に流入したリン酸液を、ラビリンス・シール溝３３により、他の構成部材を用いることなく効果的にシールすることができる。 In particular, in a phosphoric acid type fuel cell, a high concentration phosphoric acid solution is used as an electrolyte, so that the viscosity of the phosphoric acid solution increases. For this reason, in the fuel cell 3 according to the present embodiment, the phosphoric acid solution that has flowed into the through hole of the lower fastening plate 21 is effectively used by the labyrinth seal groove 33 without using other components. Can be sealed.

（第４の実施の形態）
次に、図７を参照して、本発明の第４の実施の形態について説明する。
本実施の形態に係る燃料電池４は、リン酸液の漏出阻止構造として、Ｖリング３４を用いる。以下の説明においては、燃料電池１との相違点を中心に説明し、燃料電池１と同一の部分については、同一の符号を付し、説明を省略する。 (Fourth embodiment)
Next, a fourth embodiment of the present invention will be described with reference to FIG.
The fuel cell 4 according to the present embodiment uses a V ring 34 as a phosphoric acid liquid leakage prevention structure. In the following description, differences from the fuel cell 1 will be mainly described, and the same parts as those of the fuel cell 1 will be denoted by the same reference numerals and description thereof will be omitted.

図７は、本実施の形態に係る燃料電池４の下部締付板２１の貫通孔及び締付スタッド２３ａの拡大断面図である。図７に示すように、本実施の形態に係る燃料電池４は、絶縁カラー２５ａの小径部先端の外周に固定され、下部締付板２１の上面の開口端部を加圧接触するＶリング３４を備える。Ｖリング３４は、絶縁カラー２５ａの小径部先端の外周面に嵌合され、所定の張力を有する本体部３４ａと、本体部３４ａから延在し、弾性力を有するヒンジ部３４ｂと、ヒンジ部３４ｂから延在し、弾性力により下部締付板２１の上面と加圧接触するリップ部３４ｃとを備える。本実施の形態では、このＶリング３４により、下部締付板２１の上面を加圧接触することにより、下部締付板２１の貫通孔と絶縁カラー２５ａとの間からのリン酸液の漏出を抑止する。 FIG. 7 is an enlarged cross-sectional view of the through hole of the lower fastening plate 21 and the fastening stud 23a of the fuel cell 4 according to the present embodiment. As shown in FIG. 7, the fuel cell 4 according to the present embodiment is fixed to the outer periphery of the distal end of the small diameter portion of the insulating collar 25 a and pressurizes and contacts the open end portion of the upper surface of the lower fastening plate 21. Is provided. The V ring 34 is fitted to the outer peripheral surface of the distal end of the small diameter portion of the insulating collar 25a, and has a main body portion 34a having a predetermined tension, a hinge portion 34b extending from the main body portion 34a and having elastic force, and a hinge portion 34b. And a lip portion 34c that is in pressure contact with the upper surface of the lower fastening plate 21 by elastic force. In the present embodiment, the V ring 34 pressurizes and contacts the upper surface of the lower fastening plate 21, thereby leaking the phosphoric acid solution from between the through hole of the lower fastening plate 21 and the insulating collar 25 a. Deter.

Ｖリング３４は弾性部材で構成され、その本体部３４ａは、下部締付板２１の上面側に貫通孔より突出した絶縁カラー２５ａの上端側の外周に、固有の張力により嵌合されている。本体部３４ａから延在するヒンジ部３４ｂ及びリップ部３４ｃは、本体部３４ａの設置位置と下部締付板２１との間の距離に応じて、弾性力により下部締付板２１の上面を加圧接触する。すなわち、本体部３４ａの設置位置を下部締付板２１の上面近辺に設置した場合、ヒンジ部３４ｂ及びリップ部３４ｃによる下部締付板２１の上面の加圧接触を強くすることができる。これに対し、本体部３４ａの設置位置を下部締付板２１より離して設置した場合、ヒンジ部３４ｂ及びリップ部３４ｃによる加圧接触を弱くすることができる。このように、本実施の形態では、Ｖリング３４により、下部締付板２１の上面を加圧接触することにより、電池積層部１１から流下し、下部締付板２１を流れるリン酸液の下部締付板２１の貫通孔への流入を抑制することができる。 The V-ring 34 is made of an elastic member, and its main body 34a is fitted to the outer periphery of the upper end side of the insulating collar 25a protruding from the through hole on the upper surface side of the lower fastening plate 21 with inherent tension. The hinge portion 34b and the lip portion 34c extending from the main body portion 34a pressurize the upper surface of the lower fastening plate 21 by an elastic force according to the distance between the installation position of the main body portion 34a and the lower fastening plate 21. Contact. That is, when the installation position of the main body portion 34a is set near the upper surface of the lower fastening plate 21, the pressure contact of the upper surface of the lower fastening plate 21 by the hinge portion 34b and the lip portion 34c can be strengthened. On the other hand, when the installation position of the main body portion 34a is set apart from the lower fastening plate 21, the pressure contact by the hinge portion 34b and the lip portion 34c can be weakened. As described above, in this embodiment, the upper surface of the lower fastening plate 21 is pressed and contacted by the V ring 34, thereby flowing down from the battery stack portion 11 and flowing under the phosphoric acid solution flowing through the lower fastening plate 21. The inflow to the through hole of the fastening plate 21 can be suppressed.

尚、上述した例では、本体部３４ａが絶縁カラー２５ａの外周に嵌合される例について説明したが、Ｖリング３４の配置は、リン酸液の貫通孔内への流入を抑制できるものであれば、特に限定されない。例えば、図８に示すように、形状が異なるＶリング（オイルシール）を用いてもよい。図８に示す燃料電池５において、Ｖリング３５は、本体部３５ａが下部締付板２１の貫通孔の内周面に嵌合され、本体部３５ａから貫通構内にヒンジ部３５ｂが延在している。ヒンジ部３５ｂから延在するリップ部３５ｃは、下部締付板２１の貫通孔内の絶縁カラー２５ａの外周面に加圧接触している。尚、Ｖリング３４、３５は、上述したＯリング３２や、ラビリンス・シール溝３３などと組み合わせて用いてもよい。 In the above-described example, the example in which the main body portion 34a is fitted to the outer periphery of the insulating collar 25a has been described. However, the arrangement of the V-ring 34 can suppress the inflow of the phosphoric acid solution into the through hole. There is no particular limitation. For example, as shown in FIG. 8, V-rings (oil seals) having different shapes may be used. In the fuel cell 5 shown in FIG. 8, the V ring 35 has a main body portion 35 a fitted into the inner peripheral surface of the through hole of the lower fastening plate 21, and a hinge portion 35 b extending from the main body portion 35 a into the through structure. Yes. The lip portion 35 c extending from the hinge portion 35 b is in pressure contact with the outer peripheral surface of the insulating collar 25 a in the through hole of the lower fastening plate 21. The V-rings 34 and 35 may be used in combination with the above-described O-ring 32, labyrinth seal groove 33, or the like.

Ｖリング３４としては、上述したＯリング３２と同様に、弾性力を有する材料であれば特に限定されず、各種材料を用いることができる。これらの材料の中でも、リン酸液に対する耐腐食性が高いフッ素ゴムが好ましい。また、Ｖリング３４としては、例えば、モーター等の回転軸がハウジングを貫通する際にグリースを密封する、外部からのダスト流入を防止するなどの用途で使用される各種の市販のＶリングを用いることができる。また、Ｖリング３４としては、加圧接触性を向上する観点から、各種金属バネ等で補強されたＶリングを用いることがより好ましい。 The V-ring 34 is not particularly limited as long as it is a material having an elastic force, like the O-ring 32 described above, and various materials can be used. Among these materials, fluororubber having high corrosion resistance against a phosphoric acid solution is preferable. Further, as the V-ring 34, for example, various commercially available V-rings used for applications such as sealing grease when a rotating shaft such as a motor passes through the housing or preventing dust from entering from the outside are used. be able to. Further, as the V ring 34, it is more preferable to use a V ring reinforced with various metal springs from the viewpoint of improving the press contact property.

次に、本実施の形態でのリン酸液の流路について説明する。本実施の形態では、電池積層部１１の側面から滴下したリン酸液は、流路Ｌ１を伝って、電池積層部１１の側面から下部締付板２１の上面に向けて流下する。下部締付板２１の上面に流下したリン酸液は、下部締付板２１上を下部締付板２１の端部に向けて流れる。ここで、下部締付板２１の開口端部は、Ｖリング３４のリップ部３４ｃにより、加圧接触されているので、リン酸液は貫通孔内に流入せずに下部締付板２１の端部から流路Ｌ２を伝って下部締付板２１の下面に流下する。このようにして、リン酸液の貫通孔内への流入を抑制できるので、リン酸液の貫通孔内からの漏出を抑制することができる。 Next, the flow path of the phosphoric acid solution in the present embodiment will be described. In the present embodiment, the phosphoric acid solution dropped from the side surface of the battery stack portion 11 flows down from the side surface of the battery stack portion 11 toward the upper surface of the lower fastening plate 21 through the flow path L1. The phosphoric acid solution that has flowed down to the upper surface of the lower clamping plate 21 flows on the lower clamping plate 21 toward the end of the lower clamping plate 21. Here, the opening end of the lower clamping plate 21 is in pressure contact with the lip 34c of the V-ring 34, so that the phosphoric acid solution does not flow into the through-hole and the end of the lower clamping plate 21 is reached. From the part, it flows down to the lower surface of the lower fastening plate 21 through the flow path L2. Thus, since the inflow of the phosphoric acid solution into the through hole can be suppressed, the leakage of the phosphoric acid solution from the through hole can be suppressed.

このように、本実施の形態に係る燃料電池４によれば、Ｖリング３４を用いることにより、リン酸液の貫通孔内への流入を抑制できるので、下部締付板２１の貫通孔と絶縁カラー２５ａとの間からのリン酸液の漏出を抑止することができる。特に本実施の形態では、Ｖリング３４を用いることにより、追加加工を行うことなく、容易にリン酸液の下部締付板２１の貫通孔内への流入を抑制することができる。また、Ｖリング３４としては、リン酸液に対する耐腐食性が高いフッ素系材料を含有するゴム材料を用いることもできるので、金属材料などを用いた場合と比較し、防食対策を必要とせずに長期間の使用においても、貫通孔内からのリン酸液の漏出を抑制できる耐久性が高い燃料電池を実現することができる。 As described above, according to the fuel cell 4 according to the present embodiment, by using the V ring 34, the inflow of the phosphoric acid solution into the through hole can be suppressed, so that it is insulated from the through hole of the lower fastening plate 21. Leakage of the phosphoric acid solution from between the collar 25a can be suppressed. In particular, in the present embodiment, by using the V-ring 34, it is possible to easily suppress the inflow of the phosphoric acid solution into the through hole of the lower fastening plate 21 without performing additional processing. Further, as the V-ring 34, a rubber material containing a fluorine-based material having high corrosion resistance against a phosphoric acid solution can be used, so that it is not necessary to take anti-corrosion measures compared to the case of using a metal material or the like. Even in long-term use, it is possible to realize a highly durable fuel cell capable of suppressing leakage of the phosphoric acid solution from the through hole.

さらに、本実施の形態では、Ｖリング３４の本体部３４ａの設置位置を調整することにより、下部締付板２１との加圧接触によりリップ部３４ｃが押し込まれる深さ（ストローク）を調整できるので、燃料電池４の運転に伴う温度変化による影響を軽減できる。例えば、燃料電池４は、停止時には常温となり、運転時には１５０℃から２００℃程度となる。このように、燃料電池は、運転時と停止時との温度差が大きいので、熱膨張係数の異なる材料で構成された下部締付板２１と絶縁カラー２５ａとの間に緩みが生じる現象が発生する。例えば、絶縁カラー２５ａとしてフッ素樹脂を使用し、下部締付板２１に鉄を用いた場合、絶縁カラー２５ａの熱膨張係数は、下部締付板２１の熱膨張係数の１２倍程度となり大きく異なる。本実施の形態では、Ｖリング３４を用いることにより、弾性材料で構成されたＶリング３４自体の変形及び本体部３４ａの位置の調整によるリップ部３４ｃのストロークの調整により、燃料電池４の停止時、運転時による温度変化の影響を低減できるので、長期間使用時においても信頼性が高い燃料電池を実現することができる。 Furthermore, in this embodiment, by adjusting the installation position of the main body 34a of the V-ring 34, the depth (stroke) at which the lip 34c is pushed by the pressure contact with the lower fastening plate 21 can be adjusted. In addition, it is possible to reduce the influence due to the temperature change accompanying the operation of the fuel cell 4. For example, the fuel cell 4 has a normal temperature when stopped and a temperature of about 150 to 200 ° C. during operation. As described above, the fuel cell has a large temperature difference between when it is operated and when it is stopped. Therefore, a phenomenon occurs in which looseness occurs between the lower fastening plate 21 made of a material having a different thermal expansion coefficient and the insulating collar 25a. To do. For example, when a fluororesin is used as the insulating collar 25 a and iron is used for the lower fastening plate 21, the thermal expansion coefficient of the insulating collar 25 a is about 12 times the thermal expansion coefficient of the lower fastening plate 21 and is greatly different. In the present embodiment, when the fuel cell 4 is stopped by using the V-ring 34, the V-ring 34 itself made of an elastic material is deformed and the stroke of the lip 34c is adjusted by adjusting the position of the main body 34a. Since the influence of temperature change during operation can be reduced, a highly reliable fuel cell can be realized even during long-term use.

本発明は上記実施の形態に限定されず種々変更して実施することが可能である。また、上記実施の形態で説明した数値、寸法、材質については特に制限はない。その他、本発明の目的の範囲を逸脱しない限りにおいて適宜変更することが可能である。 The present invention is not limited to the above embodiment, and can be implemented with various modifications. Moreover, there is no restriction | limiting in particular about the numerical value, dimension, and material which were demonstrated by the said embodiment. Other modifications may be made as appropriate without departing from the scope of the object of the present invention.

本発明は、例えば工業用、業務用に用いられる燃料電池、または、災害時に用いられる各種非常電源用の燃料電池に適用可能である。 The present invention can be applied to, for example, a fuel cell used for industrial use and business use, or a fuel cell for various emergency power supplies used in a disaster.

１〜５燃料電池
１１電池積層部
１２単電池
１３ａ、１３ｂセパレート板
１４電解質層
１５燃料極
１６酸化剤極
１７ａ、１７ｂ基材
１８ａ、１８ｂ冷却板
２０発電装置架台
２１下部締付板
２２上部締付板
２３ａ〜２３ｄ締付スタッド
２４ａ〜２４ｄ取付け座
２５ａ〜２５ｄ、２７ａ〜２７ｄ絶縁カラー
２６ａ〜２６ｄ、２８ａ〜２８ｄナット
２９ａ、２９ｂ出力端子
３０上部突部
３１下部突部
３２Ｏリング
３３ラビリンス・シール溝
３４、３５Ｖリング
３４ａ、３５ａ本体部
３４ｂ、３５ｂヒンジ部
３４ｃ、３５ｃリップ部 DESCRIPTION OF SYMBOLS 1-5 Fuel cell 11 Battery laminated part 12 Single cell 13a, 13b Separate plate 14 Electrolyte layer 15 Fuel electrode 16 Oxidant electrode 17a, 17b Base material 18a, 18b Cooling plate 20 Power generation device stand 21 Lower fastening plate 22 Upper fastening Plate 23a to 23d Clamping stud 24a to 24d Mounting seat 25a to 25d, 27a to 27d Insulating collar 26a to 26d, 28a to 28d Nut 29a, 29b Output terminal 30 Upper protrusion 31 Lower protrusion 31 O-ring 33 Labyrinth seal groove 34, 35 V-ring 34a, 35a Body 34b, 35b Hinge 34c, 35c Lip

Claims

A battery stack portion in which unit cells each including an electrolyte layer impregnated with a phosphoric acid solution and a pair of fuel electrode and oxidant electrode disposed on both sides of the electrolyte layer are stacked;
A gantry provided with a mounting seat for fixing the battery stack;
A first clamping plate disposed on the lower surface side in the stacking direction of the battery stack, and having a through hole;
A second clamping plate disposed on the upper surface side in the stacking direction of the battery stack part so as to sandwich the battery stack part with the first clamp plate;
A front end portion that is stretched between the first fastening plate and the second fastening plate and penetrates from the through hole of the first fastening plate to the mount side is fixed to the mounting seat, and the first seat And a clamping rod for pressure-tightening between the second clamping plates;
An insulating member interposed between the first fastening plate and the mounting seat and through which the fastening rod passes ;
A leakage prevention structure for preventing the phosphoric acid solution leaked to the upper surface of the first clamping plate from leaking to the outer peripheral portion of the insulating member from the gap between the through hole and the insulating member;
Equipped with,
The fuel cell according to claim 1, wherein the leakage prevention structure is an O-ring provided between a through hole of the first fastening plate or a portion near the through hole and an insulating member facing the insulating member .

A battery stack portion in which unit cells each including an electrolyte layer impregnated with a phosphoric acid solution and a pair of fuel electrode and oxidant electrode disposed on both sides of the electrolyte layer are stacked;
A gantry provided with a mounting seat for fixing the battery stack;
A first clamping plate disposed on the lower surface side in the stacking direction of the battery stack, and having a through hole;
A second clamping plate disposed on the upper surface side in the stacking direction of the battery stack part so as to sandwich the battery stack part with the first clamp plate;
A front end portion that is stretched between the first fastening plate and the second fastening plate and penetrates from the through hole of the first fastening plate to the mount side is fixed to the mounting seat, and the first seat And a clamping rod for pressure-tightening between the second clamping plates;
An insulating member interposed between the first fastening plate and the mounting seat and through which the fastening rod passes;
A leakage prevention structure for preventing the phosphoric acid solution leaked to the upper surface of the first clamping plate from leaking to the outer peripheral portion of the insulating member from the gap between the through hole and the insulating member;
Comprising
The leakage preventing structure, a fuel cell you wherein the lower surface of the first clamping plate is a plurality of grooves provided on the contact surface of the insulating member.

A battery stack portion in which unit cells each including an electrolyte layer impregnated with a phosphoric acid solution and a pair of fuel electrode and oxidant electrode disposed on both sides of the electrolyte layer are stacked;
A gantry provided with a mounting seat for fixing the battery stack;
A first clamping plate disposed on the lower surface side in the stacking direction of the battery stack, and having a through hole;
A second clamping plate disposed on the upper surface side in the stacking direction of the battery stack part so as to sandwich the battery stack part with the first clamp plate;
A front end portion that is stretched between the first fastening plate and the second fastening plate and penetrates from the through hole of the first fastening plate to the mount side is fixed to the mounting seat, and the first seat And a clamping rod for pressure-tightening between the second clamping plates;
An insulating member interposed between the first fastening plate and the mounting seat and through which the fastening rod passes;
A leakage prevention structure for preventing the phosphoric acid solution leaked to the upper surface of the first clamping plate from leaking to the outer peripheral portion of the insulating member from the gap between the through hole and the insulating member;
Comprising
The insulating member has a small diameter portion tip smaller in diameter than the diameter of the through hole of the first clamping plate, protruding from the through hole to the upper surface side of the first clamping plate, and the leakage prevention structure is A V-ring having a lip portion having a V-shaped cross section is fitted into the protruding portion of the small diameter portion of the insulating member, and the lip portion positioned on the upper surface side of the first fastening plate is pressed against the upper surface of the first fastening plate. fuel cell characterized in that contacted.

And a cap portion formed in a region surrounding the through hole of the first fastening plate on a lower surface of the first fastening plate, and projecting downward so that an outer edge portion is outside the outer periphery of the through hole. The fuel cell according to any one of claims 1 to 3, wherein: