Flow cell stack with single plate cells
A flow-field plate for a flow stack in a flow cell battery system is described. The flow-field plate includes first electrolyte channels formed in a molded plate to direct a first electrolyte to a first flow-field on a first side of the molded plate and second electrolyte channels formed in the molded plate to direct a second electrolyte to a second flow-field on the second side of the molded plate.
1. A flow-field plate in a flow-cell stack structure, comprising:
a molded plate having a first side and a second side;
first electrolyte channels formed in the molded plate to direct a first electrolyte to a first flow-field on the first side of the molded plate; and
second electrolyte channels formed in the molded plate to direct a second electrolyte to a second flow-field on the second side of the molded plate,
wherein the first electrolyte channels include
a first channel formed in the first side;
a second channel formed in the second side, the second channel fluidically coupled to the first channel;
a first electrolyte flow-field ingress channel formed in the first side, the flow-field ingress channel fluidically coupled to the second channel;
a first electrolyte flow-field egress channel formed in the first side opposite the first electrolyte flow-field ingress channel;
a third channel formed in the second side, the third channel fluidically coupled to the flow-field egress channel; and
a fourth channel formed in the first side, the fourth channel fluidically coupled to the third channel.
2. The flow-field plate of claim 1 , wherein the second electrolyte channels are opposite the first electrolyte channels and include
a fifth channel formed in the second side;
a sixth channel formed in the first side, the sixth channel fluidically coupled to the fifth channel;
a second electrolyte flow-field ingress channel formed in the second side, the second electrolyte flow-field ingress channel fluidically coupled to the sixth channel;
a second electrolyte flow-field egress channel formed in the second side opposite the second electrolyte flow-field ingress channel;
a seventh channel formed in the first side, the seventh channel fluidically coupled to the second electrolyte flow-field egress channel; and
an eighth channel formed in the second side, the eighth channel fluidically coupled to the seventh channel.
3. The flow-field plate of claim 2 , wherein the first channel is fluidically coupled to receive the first electrolyte from a first electrolyte ingress port, the fourth channel is fluidically coupled to expel the first electrolyte to a first electrolyte egress port, the fifth channel is fluidically coupled to receive the second electrolyte from a second electrolyte ingress port, and the eight channel is fluidically coupled to expel the second electrolyte to a second electrolyte egress port.
4. The flow-field plate of claim 3 , further including
a first seal formed around the first channel and the first electrolyte ingress port;
a second seal formed around the second channel;
a third seal formed around the third channel;
a fourth seal formed around the fourth channel and the first electrolyte egress port;
a fifth seal formed around the fifth channel and the second electrolyte ingress port;
a sixth seal formed around the sixth channel;
a seventh seal formed around the seventh channel; and
an eight seal formed around the eighth channel and the second electrolyte egress port.
5. The flow-field plate of claim 1 , wherein the second electrolyte channels include a first channel in the first side fluidically coupled to a first electrolyte flow-field ingress on the second side, and a second channel in the first side fluidically coupled to a first electrolyte flow-field egress on the second side; and wherein the first electrolyte channels include a third channel in the second side fluidically coupled to a second electrolyte flow-field ingress on the first side, and a fourth channel in the second side fluidically coupled to a second electrolyte flow-field egress on the first side.
6. The flow-field plate of claim 1 , wherein the first electrolyte channels and the second electrolyte channels are each sealed by seals formed around the first electrolyte channels and the second electrolyte channels.
7. The flow-field plate of claim 6 , wherein the first electrolyte channels and the second electrolyte channels are formed in a first depression formed in the first side of the flow-field plate and a second depression formed in the second side of the flow-field plate, the depression formed to receive a gasket that seals against the seals.
8. The flow-field plate of claim 7 , further including a third depression formed in the first depression to receive a plate.
9. The flow-field plate of claim 8 , wherein the plate is a membrane or a bipolar electrode.
10. The flow-field plate of claim 1 , further including bosses formed in each of the first electrolyte channels and the second electrolyte channels.
11. The flow-field plate of claim 10 , wherein the bosses mate with first electrolyte channels and second electrolyte channels of adjacent flow-field plates.
12. A flow-field plate, comprising
a molded plate having a first side and a second side;
a first electrolyte flow structure formed in the molded plate directing a first electrolyte through first electrolyte channels formed in both the first side and the second side through a first side flow field;
a second electrolyte flow structure formed in the molded plate directing a second electrolyte through second electrolyte channels formed in both the second side and the first side through a second side flow field; and
sealing structures formed around the first electrolyte channels and the second electrolyte channels.
13. The flow-field plate of claim 12 , further including a first depression formed in the first side that accommodates a component.
14. The flow field plate of claim 13 wherein the component is one of a membrane and a bipolar plate.
15. The flow field plate of claim 13 further including a second depression formed in the first side that accommodates a gasket that seals against the sealing structures.
16. A flow-stack, comprising:
a plurality of flow-field plates, each of the plurality of flow-field plates include a plate having a first side and a second side, first electrolyte channels formed in the plate to direct a first electrolyte to a first flow-field and second electrolyte channels formed in the plate to direct a second electrolyte to a second flow-field,
wherein the first electrolyte channels include
a first channel formed in the first side;
a second channel formed in the second side, the second channel fluidically coupled to the first channel;
a first electrolyte flow-field ingress channel formed in the first side, the flow-field ingress channel fluidically coupled to the second channel;
a first electrolyte flow-field egress channel formed in the first side opposite the first electrolyte flow-field ingress channel;
a third channel formed in the second side, the third channel fluidically coupled to the flow-field egress channel; and
a fourth channel formed in the first side, the fourth channel fluidically coupled to the third channel;
one or more membranes formed to fit within a depression in a corresponding one of the plurality of flow-field plates, each of the one or more membranes arranged such that the first flow field of one of the plurality of flow-field plates direct the first electrolyte across a first surface of membrane and the second flow field of an adjacent one of the plurality of flow-field plates directs the second electrolyte across a second surface of the membrane;
bipolar-plates formed to fit within the depression in corresponding ones of the plurality of flow-field plates such that each of the one or more membranes is between bipolar plates;
carbon felts positioned between the bipolar plates and the membranes; and a plurality of gaskets, each of the gaskets formed to engage adjacent pairs of the plurality of flow-field plates and seal the electrolyte channels.
17. The stack of claim 16 , wherein seals surround each of the first electrolyte channels and the second electrolyte channels, the gasket sealing against the seals.
18. The stack of claim 17 , wherein the gasket can be formed to accommodate bosses formed in the first electrolyte channels and the second electrolyte channels of each of the plurality of flow-field plates.
19. The stack of claim 16 , further including a pair of end plates, the plurality of flow-field plates arranged to separate the pair of end plates.
20. The stack of claim 19 , wherein the pair of end plates is compressed by compression frames.
21. The stack of claim 19 , wherein the end plates each include a raised platform to mount a current collector, the current collector contacting a bipolar plate.
22. The stack of claim 19 , further including an end gasket.