SYSTEM FOR CONTROLLING TEMPERATURE IN A FUEL CELL
Methods, articles, and systems for controlling the internal operating temperature of fuel cell systems, such as planar fuel cell arrays. The heat management system conducts heat away from the fuel cell without disturbing the flow of gases around the fuel cell layer and without the need for the equipment to disturb the flow of gases around the fuel cell layer. The present invention also provides a heat transfer system that has a low thermal mass relative to the fuel cell layer or is thermally isolated from the fuel cell layer such that the heat transfer system will not remove substantial amounts of heat from a fuel cell layer during star-up and can be activated to dissipate heat from the fuel cell only as needed.
1 . A fuel cell system comprising:
a planar fuel cell array having an anode layer and a cathode layer;
a heat transport structure in direct thermal communication with a lateral side of the cathode layer and a lateral side of the anode layer;
a heat dissipation device in direct thermal communication with the heat transport structure and indirect thermal communication with the planar fuel cell array; and
a heat removal device in indirect thermal communication with the planar fuel cell array and the heat transport structure and configured to remove heat from the heat dissipation device.
2 . The fuel cell system of claim 19 , wherein the heat transport structure has a first end and a second end opposite the first end, wherein the first end is attached to the lateral side of the cathode layer and the lateral side of the anode layer and the second end is attached to the heat dissipation device.
3 . The fuel cell system of claim 1 , wherein the heat dissipation device is a heat sink.
4 . The fuel cell system of claim 3 , wherein the fuel cell system further includes an insulation layer disposed between the heat dissipation device and the planar fuel cell array.
5 . The fuel cell system of claim 4 , wherein the fuel cell system further includes a hydrogen distribution manifold disposed on an anode side of the planar fuel cell array and wherein the hydrogen distribution manifold and the heat dissipation device are both in contact with the insulation layer and disposed on opposite sides of the insulation layer.
6 . The fuel cell system of claim 1 , further including a temperature sensor configured to measure an operating temperature of the planar fuel cell and activate the heat removal means.
7 . The fuel cell system of claim 1 , wherein the heat dissipation device and the heat transport structure have a combined thermal mass that is no more than 200% larger than a total thermal mass of the planar fuel cell array.
8 . The fuel cell system of claim 7 , wherein the fuel cell system further includes an insulation layer disposed between the heat dissipation device and the planar fuel cell array.
9 . The fuel cell system of claim 1 , wherein the heat removal device is a cooling system that includes a heat transfer fluid that is not air.
10 . The fuel cell system of claim 1 , wherein the heat removal device includes a Peltier cooler.
11 . The fuel cell system of claim 1 , wherein the system is devoice of fans that modify the airflow over a cathode surface of the planar fuel cell array.
12 . The fuel cell system of claim 1 , wherein the planar fuel cell array has a power to weight ratio of 2 Watts per gram or less.
13 . The fuel cell system of claim 1 , wherein the fuel cell system is contained within a hand-held electronics device.
14 . A fuel cell system comprising:
a planar fuel cell array;
a heat transport structure in direct thermal communication with the planar fuel cell array;
a heat dissipation device in direct thermal communication with the heat transport structure and indirect thermal communication with the planar fuel cell array;
an insulation layer disposed between the heat dissipation device and the planar fuel cell array; and
a heat removal device in indirect thermal communication with the planar fuel cell array and the heat transport structure and configured to remove heat from the heat dissipation device.
15 . The fuel cell system of claim 14 , wherein the heat dissipation device and the heat transport structure have a combined thermal mass that is no more than 200% larger than a total thermal mass of the planar fuel cell array.
16 . The fuel cell system of claim 14 , wherein the fuel cell system further includes a hydrogen distribution manifold disposed on an anode side of the planar fuel cell array and wherein the hydrogen distribution manifold and the heat dissipation device are both in contact with the insulation layer and disposed on opposite sides of the insulation layer.
17 . The fuel cell system of claim 14 , wherein the insulation layer is less than 1 millimeter thick.
18 . The fuel cell system of claim 14 , wherein the insulation layer has a thermal conductivity of 10 W/mK or less.
19 . A fuel cell system comprising:
a planar fuel cell array;
a heat transport structure in direct thermal communication with the planar fuel cell array;
a heat dissipation device in direct thermal communication with the heat transport structure and indirect thermal communication with the planar fuel cell array, wherein the heat dissipation device and the heat transport structure have a combined thermal mass that is no more than 200% larger than a total thermal mass of the planar fuel cell array; and
a heat removal device in indirect thermal communication with the planar fuel cell array and the heat transport structure and configured to remove heat from the heat dissipation device.
20 . The fuel cell system of claim 19 , wherein the planar fuel cell array includes an anode layer and a cathode layer and wherein the heat transport structure is in direct thermal communication with a lateral side of the cathode layer and a lateral side of the anode layer.