Description:Complete Specification

The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed.
Field of the invention
[0001] This invention relates to a water separator of a fuel cell stack, and more specifically to a heater-filter integrated module that is positioned within the water separator of the fuel cell stack.

Background of the invention
[0002] DE102019212882 A1 describes a heating device with at least one electrically operated heating element and a heat distribution element thermally coupled to the heating element. The heating element has at least one PTC thermistor. The electrical resistance of the heating element has a PTC thermistor characteristic in its temperature curve and that the electrical resistance of the heating element has a minimum value (Rmin) in its temperature curve which is less than 1.5 ohms.

Brief description of the accompanying drawing
[0003] Figure 1 illustrates a heater-filter integrated module that is positioned within the water separator of the fuel cell stack in one embodiment of the invention.

Detailed description of the embodiments
[0004] Figure 1 illustrates a water separator 100 for separating water from moist hydrogen gas that is channeled from a fuel cell stack. The water separator 100 comprises a housing 110, and at least one filter element 120 positioned within the housing 110. The at least one filter element 120 is adapted to filter particulate matter from the moist hydrogen gas that is channeled to the water separator 100 from the fuel cell stack. At least one heating element 130 is positioned within the housing 110 of the water separator 100, the at least one heating element 130 adapted to heat and thaw ice that is present within the water separator 100 to convert ice to water in a liquid state.

[0005] Figure 1 illustrates a water separator 100 for separating water from moist hydrogen gas that is channeled from a fuel cell stack and recirculated back to the fuel cell stack. The water separator 100 comprises a housing 110 that includes two inlet ports (165,175) and one outlet port (185). The two inlet ports (165,175) of the water separator 100 are adapted to receive moist hydrogen gas that flows from a fuel cell stack and withdraws the moisture from the moist hydrogen before recirculating the dry hydrogen gas to the fuel cell stack. In an exemplary embodiment, the water separator 100 comprises at least one filter element 120 positioned within the housing 110. The at least one filter element 120 that is positioned within the first inlet port 165 and within the second inlet port 175 is adapted to filter particulate matter from the moist hydrogen gas that is channeled to the water separator 100 from the fuel cell stack. Once the moist hydrogen gas is filtered by means of the at least one filter element 120 that is positioned within the first inlet port 165 and within the second inlet port 175 to separate the particulate matter from moist hydrogen gas, the moist hydrogen gas is admitted within the water separator to separate the water from the moist hydrogen gas before recirculating the dry hydrogen gas back to the fuel cell stack. When the fuel cell stack is no longer in operation, the water that is accumulated within the water separator freezes when exposed to low atmospheric temperatures over an extended period of time. The water that freezes within the water separator prevents the flow of moisture laden hydrogen to flow through the water separator from the fuel cell stack when the fuel cell is operated initially. Therefore, for the water separator to function normally again, the moisture that is frozen within the water separator requires to be thawed completely.

[0006] In an exemplary embodiment, at least one heating element 130 is positioned within the housing 110 of the water separator 100. The at least one heating element 130 that is positioned within the housing 110 of the water separator 100 is adapted to heat and thaw ice that is present within the water separator 100 to convert ice to water in a liquid state. In an exemplary embodiment, the at least one filter element 120 positioned within the housing 110 is manufactured from a PEEK fabric material. The at least one heating element 120 that is positioned within the housing 110 of the water separator 100 comprises an aluminum thermal transfer body 140 that is in thermal communication with the at least one heating element 130 positioned within the housing 110 of the water separator 100. More specifically, the aluminum thermal transfer body 140 is adapted to absorb heat from the at least one heating element 130 that is positioned within the housing 110 of the water separator 100. Therein, the aluminum thermal transfer body 140 transfers the heat to the ice that surrounds the aluminum thermal transfer body 140 to thaw the ice that surrounds the aluminum thermal transfer body 140. In an exemplary embodiment, the at least one heating element 130 that is positioned within the housing 110 of the water separator 100 comprises PTC Barium Titanate Ceramic 150 that is a source of heat. The PTC Barium Titanate Ceramic 150 is secured to the aluminum thermal transfer body 140 to transfer the heat from the at least one heating element 130 that is positioned within the housing 110 of the water separator 100 to the aluminum thermal transfer body 140 by conduction. Therein, from the aluminum thermal transfer body 140, the heat is transferred to the ice that surrounds the aluminum thermal transfer body 140 which ultimately gets thawed.

[0007] In an exemplary embodiment, the at least one heating element 130 that is positioned within the housing110 of the water separator 100 comprises at least one stainless steel busbar 160 that is secured to the PTC Barium Titanate Ceramic 150 and adapted to conduct heat away from the PTC Barium Titanate Ceramic 150. In addition, the at least one heating element 130 that is positioned within the housing 110 of the water separator 100 comprises at least one premold Nylon PA66 170 that is secured to the at least one stainless steel busbar 160. Therefore, the PTC Barium Titanate Ceramic, the at least one stainless steel busbar, and the at least one premold Nylon PA66 constitute an integrated at least one heating element 130 that is positioned within the housing 110 of the water separator 100. In an exemplary embodiment, a spring steel clip 182 comprises a first end portion 183, a second end portion 184, and a body position defined between the first end portion 183 and the second end portion 184. The first end portion 183 and the second end portion 184 of the spring steel clip 182 and positioned adjacent to either ends of the aluminum thermal transfer body 140. The body portion 185 of the spring steel clip 182 abuts against the at least one premold Nylon PA66 170 such that the spring steel clip 182 is adapted to secure the at least one premold Nylon PA66 170 against the at least one stainless steel busbar 160. Thereby, the at least one heating element 130 that is positioned within the housing 110 of the water separator 100 is secured firmly against the aluminum thermal transfer body 140 to constitute an integral assembly. The housing 110 of the water separator 100 comprises one of a plastic overmold PA9T-GF35 Ultramid and a PPS-GF40 Xytron material.

[0008] A working of the water separator 100 for separating water from moist hydrogen gas that is channeled from the fuel cell stack is described as an example. Moist hydrogen is channeled within the water separator 100 via the at least one filter element 120 positioned within the housing 110. More specifically, the at least one filter element 120 is adapted to filter particulate matter from the moist hydrogen gas that is channeled to the water separator 100 from the fuel cell stack. When water freezes inside the water separator 100, it is required to be thawed to operate the water separator 100. Therein, electric power is supplied to the at least one heating element 130 that is positioned within the housing 110 of the water separator 100. The heat that is supplied by the at least one heating element 130 that is positioned within the housing 110 of the water separator 100 is transferred to the aluminum thermal transfer body 140 by conduction. Once the aluminum thermal transfer body 140 get heated due to thermal contact with the at least one heating element 130 that is positioned within the housing 110 of the water separator 100, the heat is transferred from the aluminum thermal transfer body 140 to the ice that surrounds the aluminum thermal transfer body 140 and that required to be thawed. Therein, once the ice thaws, the water separator 100 may be operated once more thereby permitting the flow of moist hydrogen through the water separator 100 to separate the water from the moist hydrogen before recirculating the hydrogen gas back to the inlet of the fuel cell stack.

[0009] It must be understood that the embodiments explained above are only illustrative and do not limit the scope of the disclosure. Many modifications in the embodiments with regard to dimensions of various components are envisaged and form a part of this invention. The scope of the invention is only limited by the scope of the claims.

, Claims:We Claim

1. A water separator (100) for separating water from moist hydrogen gas that is channeled from a fuel cell stack, said water separator (100) comprising:
a housing (110);
at least one filter element (120) positioned within said housing (110), said at least one filter element (120) adapted to filter particulate matter from the moist hydrogen gas that is channeled to the water separator (100) from said fuel cell stack; and
at least one heating element (130) positioned within said housing (110) of said water separator (100), said at least one heating element (130) adapted to heat and thaw ice that is present within said water separator (100) to convert ice in a solid state to water in a liquid state.

2. The water separator (100) for separating water from moist hydrogen gas that is channeled from a fuel cell stack in accordance with Claim 1, wherein said at least one filter element (120) positioned within said housing (110) is manufactured from a PEEK fabric material.

3. The water separator (100) for separating water from moist hydrogen gas that is channeled from a fuel cell stack in accordance with Claim 1, further comprising an aluminum thermal transfer body (140) in thermal communication with said at least one heating element (130) positioned within said housing (110) of said water separator (100), said aluminum thermal transfer body (140) adapted to absorb heat from said at least one heating element (130) positioned within said housing (110) of said water separator (100) and transfer the heat to ice that surrounds said aluminum thermal transfer body (140) to thaw the ice that surrounds said aluminum thermal transfer body (140).

4. The water separator (100) for separating water from moist hydrogen gas that is channeled from a fuel cell stack in accordance with Claim 1, wherein said at least one heating element (130) positioned within said housing (110) of said water separator (100) comprises PTC Barium Titanate Ceramic (150) that is a source of heat.

5. The water separator (100) for separating water from moist hydrogen gas that is channeled from a fuel cell stack in accordance with Claim 4, wherein said at least one heating element (130) positioned within said housing (110) of said water separator (100) comprises at least one stainless steel busbar (160) that is secured to said PTC Barium Titanate Ceramic (150) and adapted to conduct heat away from said PTC Barium Titanate Ceramic (150).

6. The water separator (100) for separating water from moist hydrogen gas that is channeled from a fuel cell stack in accordance with Claim 5, wherein said at least one heating element (130) positioned within said housing (110) of said water separator (100) comprises at least one premold Nylon PA66 (170) that is secured to said at least one stainless steel busbar (160).

7. The water separator (100) for separating water from moist hydrogen gas that is channeled from a fuel cell stack in accordance with Claim 1, further comprising a spring steel clip (182) that is adapted to secure said at least one premold Nylon PA66 (170) against the at least one stainless steel busbar (160).

8. The water separator (100) for separating water from moist hydrogen gas that is channeled from a fuel cell stack in accordance with Claim 1, wherein said housing (110) of said water separator (100) comprises one of a plastic overmold PA9T-GF35 Ultramid and a PPS-GF40 Xytron.