Fuel cell bipolar plate alloys
Fuel cell alloy bipolar plates. The alloys may be used as a coating or bulk material. The alloys and metallic glasses may be particularly suitable for proton-exchange membrane fuel cells because of they may exhibit reduced weights and/or better corrosion resistance. The alloys may include any of the following Al x Cu y Ti z , Al x Fe y Ni z , Al x Mn y Ni z , Al x Ni y Ti z , Cu x Fe y Ti z , Cu x Ni y Ti z , Al x Fe y Si z , Al x Mn y Si z , Al x Ni y Si z , Ni x Si y Ti z , and C x Fe y Si z . The alloys or metallic glass may be doped with various dopants to improve glass forming ability, mechanical strength, ductility, electrical or thermal conductivities, hydrophobicity, and/or corrosion resistance.
1 . A bipolar plate of a fuel cell, the bipolar plate comprising:
a body defining a first surface and a second surface, the first and second surfaces having (i) at least a partially amorphous structure and (ii) a composition represented by a formula: Cu x Fe y Ti z or Cu x Ni y Ti z ; where x is 0.1 to 0.75; y is 0.05 to 0.45; z is 0.05 to 0.8 and the sum of x, y, and z is 1, at least one of the first and second surfaces forming an outermost surface exposed to one or more flow passages when arranged in the fuel cell.
2 . The bipolar plate of claim 1 , wherein the composition is formed on a substrate, and has a corrosion current that is less than the corrosion current of the substrate.
3 . The bipolar plate of claim 1 , wherein the composition has a corrosion current that is less than 10 μA/cm 2 .
4 . The bipolar plate of claim 1 , wherein the composition has the formula: Cu x Ni y Ti z ; where x is 0.1 to 0.75, y is 0.05 to 0.45, and z is 0.25 to 0.75.
5 . The bipolar plate of claim 1 , wherein the composition is doped with less than or equal to 1 at. % of an element selected from the group consisting of La, P, B, C, Co, Zr, Cr, Nb, Mo, W, Sn, and a combination thereof.
6 . The bipolar plate of claim 1 , wherein the first and second surfaces have a thickness of 1 nm to 500 μm.
7 . The bipolar plate of claim 1 , wherein the composition has the formula: Cu x Fe y Ti z ; where x is 0 . 35 to 0 . 55 ; y is 0 . 05 to 0 . 1 ; and z is 0 . 4 to 0 . 6 .
8 . The bipolar plate of claim 1 , wherein the composition has the formula: CuxNiyTiz, where x is 0.3 to 0.6, y is 0.1 to 0.4, and z is 0.3 to 0.7.
9 . The bipolar plate of claim 4 , wherein x is 0.3 to 0.6, y is 0.1 to 0.4, and z is 0.3 to 0.7.
10 . The bipolar plate of claim 1 , wherein the composition has a formula selected from the from the group consisting of Cu 0.35 Fe 0.05 Ti 0.6 , Cu 0.4 Fe 0.1 Ti 0.5 , Cu 0.45 Fe 0.05 Ti 0.5 , Cu 0.55 Fe 0.05 Ti 0.4 , Cu 0.05 Ni 0.2 Ti 0.75 , Cu 0.2 Ni 0.1 Ti 0.7 , Cu 0.3 Ni 0.1 Ti 0.6 , Cu 0.4 Ni 0.1 Ti 0.5 , Cu 0.5 Ni 0.1 Ti 0.4 , and Cu 0.6 Ni 0.1 Ti 0.3 .
11 . The bipolar plate of claim 2 , wherein the substrate is a metal substrate.
12 . The bipolar plate of claim 11 , wherein the substrate includes steel, titanium, nickel, aluminum, and/or copper.
13 . The bipolar plate of claim 12 , wherein the substrate is steel or aluminum.
14 . The bipolar plate of claim 1 , wherein the composition has the formula: Cu x Fe y Ti z ; where x is 0.4 to 0.5, y is 0.06 to 0.09, and z is 0.45 to 0.55.
15 . The bipolar plate of claim 1 , wherein the composition has an electrical conductivity greater than 100 S/cm.
16 . The bipolar plate of claim 2 , wherein an interfacial contact resistance between the substrate and the composition is less than 0.1 Ω/cm 2 .
17 . A fuel cell comprising:
a proton exchange membrane;
a plurality of catalyst electrode layers; and
bipolar plates defining one or more flow passages, the bipolar plates including a substrate consisting of steel, titanium, nickel, aluminum, and/or copper, and an alloy directly disposed on the substrate and arranged to contact fuel and/or by-products traveling in the one or more flow passages, the alloy having at least a partially amorphous structure and a formula:
Cu 0.35 Fe 0.05 Ti 0.6 , Cu 0.4 Fe 0.1 Ti 0.5 , Cu 0.45 Fe 0.05 Ti 0.5 , Cu 0.55 Fe 0.05 Ti 0.4 , Cu 0.05 Ni 0.2 Ti 0.75 , Cu 0.1 Ni 0.2 Ti 0.7 , Cu 0.2 Ni 0.1 Ti 0.7 , Cu 0.30 Ni 0.1 Ti 0.6 , Cu 0.4 Ni 0.1 Ti 0.5 , Cu 0.5 Ni 0.1 Ti 0.4 , or Cu 0.6 Ni 0.1 Ti 0.3 .