By: Greg Sanchez

Making an environmental friendly hydrogen fuel cell vehicle affordable to people like you and me come at a high premium for the big three, you know – GM, Ford & DaimlerChrysler. In fact, the dilemmas that these automakers must solve in order to eventually mass-produce it are very complex and very many, and of course the main challenge is the cost of it. In fact, General Motors reported not too long ago, that they spend over $500 million every year on just hydrogen fuel cell research; however, the element that makes the entire project almost incalculable in the money department may come as a very big surprise to all of us! It’s called the fuel cell stack, and I can try to explain it as best as I have learned it. The stack happens when hydrogen fuses with oxygen to create electricity and thus power these experimental vehicles.

Fuel Cells generate electricity through an electrochemical process in which the energy stored in a fuel is converted directly into DC electricity. Because electrical energy is generated without combusting fuel, fuel cells are extremely attractive from an environmental standpoint. Attractive fuel cell characteristics include: high-energy conversion efficiency, modular design, very low chemical and acoustical pollution, fuel flexibility, cogeneration capability, and rapid load response.
All fuel cells have the same basic operating principle. An input fuel is catalytically reacted (electrons removed from the fuel elements) in the fuel cell to create an electric current. Fuel cells consist of an electrolyte material, which is sandwiched in between two thin electrodes (porous anode and cathode). The input fuel passes over the anode (and oxygen over the cathode) where it catalytically splits into ions and electrons. The electrons go through an external circuit to serve an electric load while the ions move through the electrolyte toward the oppositely charged electrode. At the electrode, ions combine to create by-products, primarily water and CO2. Depending on the input fuel and electrolyte, different chemical reactions will occur.

That brings us back to hydrogen. Hydrogen could be described as the perfect fuel. It is non-polluting, high in energy, and able to be used directly in internal combustion engines or indirectly in fuel cells. Much of the vehicle technology used to store propane and natural gas in vehicles can be adapted to hydrogen. One of the problems with hydrogen is the limited range because of on-board vehicle storage. This is being overcome gradually by using storage tanks capable of operating at 10,000 psi, electronic fuel pressure regulation, and efficient engine design.
Another problem with hydrogen is getting it to the consumer. There is no delivery system currently in place, but the solution has been developed and the delivery infrastructure products are waiting for the first hydrogen-fueled vehicles to hit the market place.

According to one of GM’s fuel cell scientist, creating an affordable on-board hydrogen storage system is the number-one challenge looming over all of us researchers. “The fuel cell is most expensive right now, but if we get the cost lowered, then compressed tanks will be the most expensive part,” said Dr. Christopher Borroni-Bird, director of GM’s Autonomy and HyWire vehicle programs. Dr. Borroni-Bird won’t say how much the automaker spends on its compressed hydrogen storage systems, which it’s really a ‘new term’ or fancy way of calling tomorrow’s gas tanks – but mass-produced compressed natural gas tanks in today’s automotive applications are roughly between $2,000 and $3,000 of the vehicle’s entire cost.

According to the U.S. Department of Energy, it is estimated that one carbon fiber-lined, 5000-psi tank will probably cost almost $700 to manufacture, but that’s only if they’re mass-produced at a rate of 500,000 units per year.

What’s driving on-board hydrogen storage costs so high, however, shouldn’t be surprising in the least. First of all, to achieve a range that would make hydrogen fuel cell vehicles practical and commercially feasible, it would have to perform up to about 300 miles, which means that a compressed hydrogen storage system of at least 10,000 psi would be necessary to fulfill that challenge; and that’s a lot of hazardous gas under high pressure, so researchers think they’ll need to over-engineer the systems to alleviate safety concerns like perhaps designing a fuel tank that would be ‘sort of’ unbreakable, ‘sort of’ bulletproof, and as a matter of fact, there is a company in southern California that provides General Motors with a pair of 10,000-psi tanks that are basically wrapped in Kevlar, the same carbon fiber material found in bullet-proof vests. When it comes to ‘on-board’ storage the safety concerns are very high and will take many more thousands of man-hour to solve the issue. The mere thought of having a 10,000 psi hydrogen storage tank under your seat is just not encouraging.

Another matter that’s driving research cost as well is packaging. Today’s tanks for the hydrogen storage systems are massive and heavy, so automakers will have to design them lighter and place them in a comfortable yet safe place, in fact, when production time nears, they will have to shrink them without compromising the vehicle’s range.
GM’s vision for the future is its $10 million HyWire hydrogen fuel cell proof of concept, which calls for almost a complete reinvention of the automobile, as we know it. And although the progress researchers have made in the last 10 years is incredible, there is yet a lot to go.