Why are cars not being made with fuel cells?
They are already!
Unfortunately vehicles developed and powered by fuel cells are technologically problem prone, but some significant progress has been made already. Although cost prohibitive; eventually the consumers own demand coupled with the high cost of fossil fuels (and environmental problems concerned with hydrocarbons) will help to spur on fuel cell development futher.
The real question is; How soon will we see fuel cell powered cars mainstream?
The answer inevitably is when technological barriers are overcome to enable fuel cell developers to economically roll-out vehicles powered this way. In other words given time, expertise, and learning to understand and develop fuel cell technology properly (particularly economically derived hydrogen power) as well as consumer demand for cleaner alternatives to hydrocarbons will we ultimately see them at the forefront of our transportation system.
I think the DMFC (Direct Methanol Fuel Cell) will probably be the leading fuel cell technology that will prevail.
I attribute this to the fact that it is much easier and less energy intensive to extract the hydrogen from Methanol and convert it to electricity (or burn the hydrogen directly in a combustion engine) than it is for hydrogen derived from H2O. This is hydrogen on demand - as and when your engine needs it (produced at the source) rarther than carrying potentially dangerous cryogenic or pressurised hydrogen fuel tanks.
The downside to all this however is that Methanol is mostly produced using methane and other fossil hydrocarbons which sort of defeats the objective. As in the early days prior to the utilisation of crude oil; Methanol can be produced in other more environmentally friendly ways (for example by using biomass) but a major shift for change would be required as well as a rekindling of forgotten methanol production techniques.
Methanol Links are to the left
Because they are too expensive, big and heavy, the only way is to use them is in a pick-up truck, you place all the cells on the bed and even this way the range will be too short !, not more than 40 miles with one charge........