Toyota Shatai Kabushiki Kaisha

Toyota Jidosha Kabushiki Kaisha

Toyota Jidosha Kabushiki Kiasha

Kousuke Kawajiri

Satoshi Futami

Keiji Hashimoto

Takamasa Kanie

Hiroki Okabe

Kazunori Shibata

Tomokazu Hayashi

Hiroya Nakaji

Yoshinori Shinozaki

Nobuaki Nonoyama

Kazunari Moteki

Yuki Sugino

A fuel battery includes unit cells, each of which includes a membrane electrode assembly having two gas diffusion layers. Gas passage forming bodies are stacked on an outer surface of each of the gas diffusion layers of each of the unit cells so that each of the unit cells includes a fuel gas passage and an oxidant gas passage. Each of the gas passage forming bodies includes water guide passages, each of which is located between adjacent ones of the gas passages. A communication passage is arranged between each of the gas passages and an adjacent one of the water guide passages to guide water from the gas passage to the water guide passage. The communication passage has a higher pressure loss than that of the gas passage.

Fuel cell

A fuel cell includes a first separator and a second separator. A second protrusion is formed on a first sealing portion of the first separator. A concave portion is formed in a second sealing portion of the second separator. When fuel cells are stacked together sequentially in the vertical direction without displacing relative to one another, the center of the second protrusion and the center of the concave portion are aligned with each other. Even if the fuel cells are displaced while being stacked together, the upper fuel cell in the vertical direction is moved to decrease the distance between the center of the second protrusion and the center of the corresponding concave portion.

Fuel cell stack

A channel forming body used in a fuel cell module has a gas channel, a water conduit, and a communication path that provides communication between the gas channel and the water conduit. When a ridge is seen in a cross-section perpendicular to a channel extension direction, one of both ends of an external shape of the ridge is shaped so as to be located closer to a center of the ridge than an imaginary surface of the channel assumed to extend in a straight line along the channel extension direction. Portions of the ridge located closer to the center of the ridge are formed opposite from each other at left and right ends of the external shape of the ridge with the communication path interposed therebetween.

Fuel cell module with arranged ridge segments

A gas channel forming plate is arranged between a membrane electrode assembly and a flat separator base. The gas channel forming plate includes gas channels arranged on a surface that faces the membrane electrode assembly, water channels each formed on the back side of the protrusion between an adjacent pair of the gas channels, communication passages that connect the gas channels and the water channels to each other, and guide portions formed by causing an inner wall surface of a gas channel to protrude inward in the gas channel. The guide portions are formed such that the upstream edge of each communication passage is arranged in a range in which, in the velocity vector of the gas flowing in the gas channel, the directional component directed from the side corresponding to the membrane electrode assembly toward the flat separator base has a positive value.

Gas channel forming plate for fuel cell and fuel cell stack

A gas passage forming body for a fuel battery includes gas passages and water guide passages. A communication passage is arranged between one of the water guide passages and a gas passage that is adjacent to the water guide passage and is in communication with the adjacent gas passage and water guide passage to permit water to move therethrough. An aid portion is arranged at water drainage ends of two adjacent ones of the water guide passages and aids bonding of water drained from the water drainage ends of the two adjacent ones of the water guide passages. Thus, water drainage from the water guide passages of the gas passage forming body is improved, and water in the gas passages is reduced. As a result, the battery performance of the fuel battery is improved due to an improvement in gas diffusion.

Gas flow path forming bodies of fuel cell, and fuel cell

A gas flow passage-forming member is disposed between a membrane electrode and gas diffusion layer assembly and a separator of a fuel cell, and the gas flow passage-forming member is configured to form a gas flow passage. The gas flow passage-forming member has a corrugated shape such that groove portions and ridge portions are provided on each of a front side and a back side of the gas flow passage-forming member. The groove portions each serve as the gas flow passage. The gas flow passage-forming member has communication holes providing communication between the front side and the back side, and the communication holes are provided in a region downstream of an upstream region in a gas flow direction. The upstream region is a non-communication region with no communication hole.

Gas flow passage-forming member and cell for fuel cell

A gas channel forming plate includes protrusions, which extend parallel with each other, gas channels that are respectively located between each adjacent pair of the protrusions, and water channels, which are respectively formed on the back surface of each protrusion. Each protrusion includes first communication portions and second communication portions. Each first communication portion includes a first opening. Each second communication portion includes a second opening. The second communication portions of each protrusion constitute an expanding region, in which the opening area of the second opening in each second communication portion is greater than the opening area of the first opening of each first communication portion, to limit introduction of water to the water channel on the back side of the protrusion using capillary action by the second communication portions.

A gas channel forming member is located between a separator and a membrane electrode assembly. The gas channel forming member includes gas channels, which are arranged in parallel with each other on a surface that faces the membrane electrode assembly, water channels, which are formed on a surface that faces the separator, and inner communication passages. The water channels are each located between adjacent two of the gas channels. The inner communication passages communicate the gas channels and the water channels with each other. Each water channel is formed such that the flow cross-sectional area in an outlet section including an outlet opening is larger than the cross-sectional area of an upstream section, which is upstream of an adjacent to the outlet section in the flow direction of the oxidant gas.

Gas channel forming member for fuel cells, and fuel cell

Gas flow channels are provided between protrusions arranged in parallel on a first surface of a partition wall of a gas flow channel forming body, and water introduction channels are provided in valleys on the opposite side of each protrusion, on a second surface. In order to allow the gas flow channels and the water introduction channels to communicate so that water can pass there through, communication channels is provided to the partition wall. Intermediate structures are correspondingly provided inside the water introduction channels to the communication channels. A set of communication channels is formed by a pair of communication channels positioned at a first interval. A set of communication channels and another set of communication channels adjacent thereto are positioned on each protrusion with a second interval therebetween.

Gas flow channel forming body for fuel cell, and fuel cell

A fuel battery includes an oxidant gas flow passage having a downstream section, in which a gas diffusion porous body is arranged. The fuel battery includes a fuel gas flow passage having a downstream section, in which a gas diffusion porous body is arranged. A cooling medium flow passage is formed between a first separator of each unit cell of the fuel battery and a second separator of a unit cell adjacent to the unit cell. The flowing direction of a cooling medium in the cooling medium flow passage is the same as that of oxidant gas in the oxidant gas flow passage. An upstream section of the cooling medium flow passage is located closer to a surface of a membrane-electrode assembly that faces the oxidant gas flow passage adjacent to the cooling medium flow passage as compared with a downstream section of the cooling medium flow passage.

Fuel battery

An electrode structureis received in a joint portion of frames. A first gas diffusion layerand a first gas passage forming memberare arranged on a first surface of the electrode structure. A second gas diffusion layerand a second gas passage forming memberare formed on a second surface of the electrode structure. A separatoris joined with a surface of the frameand a surface of the gas passage forming member. A separatoris joined with a surface of the frameand a surface of the gas passage forming member. A water passageis formed between a flat plateof the gas passage forming memberand the separator. The water passagehas a depth set to a value smaller than depth of a gas passage Tof the gas passage forming member. Generated water is introduced from the gas passage Tof the gas passage forming memberto the water passagethrough capillary action via communication holes. The generated water in the water passageis moved to a downstream side of the water passageby pressure caused by oxidization gas. This prevents corrosion of the cathode side electrode catalyst layer and improves durability of the anode side gas passage forming member. As a result, a fuel cell capable of preventing decrease of power generation is provided.

A membrane electrode assembly () formed by a solid electrolyte membrane () and electrode catalyst layers () is interposed between a pair of frames (). Gas diffusion layers () are laminated onto the surface of the electrode catalyst layers (). A first gas passage forming member () is laminated onto the surface of the gas diffusion layer () while a second gas passage forming member () is laminated onto the surface of the gas diffusion layer (). Separators () contact surfaces of the frame () and the first and second gas passage forming member (). A plurality of first and second straight grooves () are formed on the first gas passage forming member (), such that the widths (w, w) differ from each other, and cross-sectional areas of the paths for the first and second gas passages (T, T) differ from each other.

An electrode structureis accommodated in a joint portion of framesand. A first gas diffusion layerand a first gas passage forming memberare laid on a first surface of the electrode structure, and a second gas diffusion layerand a second gas passage forming memberare laid on a second surface of the electrode structure. A separatoris joined to surfaces of the frameand the gas passage forming member, and a separatoris joined to surfaces of the frameand the gas passage forming member. A porous layerhaving continuous pores is located between the gas passage forming memberand the separator. A drainage promoting memberformed of a porous material having continuous pores is provided to communicate with a downstream end of a second gas passage Tof the second gas passage forming memberand to communicate with a downstream end of the continuous pores of the porous layer. Generated water that has been drawn into the porous layerfrom the second gas passage Tby capillary action flows downstream by surface tension of water, and is then drawn into the drainage promoting member. The water drawn in by the drainage promoting memberis discharged into a discharging passage by fluid pressure of oxidation off-gas that flows from the second gas passage Tinto the continuous pores of the drainage promoting member. Accordingly, a fuel battery is provided in which generated water is prevented from remaining in the second gas passage Tof the cathode side second gas passage forming member, and it is possible to prevent the power generation performance from being lowered by insufficient supply of oxidation gas to the electrode structure

Growing community of inventors

Kariya, Japan

Kousuke Kawajiri