Vehicles powered by a conventional fossil fuel or biofuel based ICE, the energy storage system is of crucial importance for electric vehicles (EVs).
Two major options exist:
one is the storage of electrical energy using batteries,
the other one is the storage of energy in form of hydrogen.
The development of such EV concepts has a very long tradition at General Motors (GM) and Opel, regardless whether fuel cell electric vehicles (FCEVs), pure battery electric vehicles (BEVs), or hybrid variants are concerned. For instance, the world’s first fuel cellEV, the GM Electrovan of 1966 was developed and designed by GM. Over the course of the late 1990s, this technology was revived and reintroduced within the framework of a large-scale development program. These efforts lead to the development of the current GM HydroGen4 fuel cell car, a mid-sized crossover vehicle based on the Chevrolet Equinox.
During the 1990s, a large development effort on pure BEVs started.
The depletion of the fossil resources and the climatic change caused by CO2 emissions have made the development of zero-emission vehicles very important in the last few years.
There are around 900 million vehicles worldwide are on the roads today.
About 96% of the fuel used for propulsion purposes is thereby produced from fossil sources of energy.
There are estimates for the year 2020 that the number mentioned above will increase to approximately 1.1 billion vehicles,
This will inevitably have consequences for global crude oil demand and for the worldwide CO2 emissions.
Since an increase in demand of oil and CO2 production proportional to the projected number of vehicles is not sustainable for financial, ecological, and political reasons, every implementation strategy must aim at the replacement of fossil fuels as a source of energy for automotive applications.
We need to urgently head towards using zero-emission vehicles using an electric powertrain system based on hydrogen fuel cells or purely battery electric systems that are fully competitive with ICE vehicles.
A vehicle with a range of 500 km, using diesel technology, a tank system that weighs approximately 45 kg and requires a volume of just less than 50 l is needed.
A similar zero-emission vehicle on hydrogen weighs about 125 kg
The energy storage gets even heavier if a future highly advanced lithium-ion (Li-ion) battery system (usable system energy density: 120 Wh/kg; current technology is closer to 85 Wh/kg)
The weight of the energy storage system would be just below one metric ton to provide a range of 500 km (at current technology levels).
A hydrogen tank can be refilled completely within 3–5 min, very similar to a conventional diesel tank.
Recharging a battery can take 15 minutes to overnight.
A hydrogen tank system for a vehicle range of 500 km could be manufactured for approximately US$ 3,000 a comparable 100 kWh battery would cost approximately US$ 50,000.
It would be sensible to develop and use a BEV for a driving and duty cycle for which a smaller battery and a lower range is sufficient and viable.
Infrastructure Issues.
EV charging infrastructure is getting better, but with constant reports of lack of service to charge points and not enough, users are not confident of being able to get from a to b.
To set up a enough filling station infrastructure, for example, 9,000 charging stations need to be built.
On the UK motorways connecting these large cities and town, a filling station would have to be installed every 25 miles.
This highway network would correspond to 2,000 additional stations.
Such a comprehensive filling station network could serve about 1 million electric vehicles.
Similar to today’s petrol/diesal infrastructure, an electric charging station would be able to serve hundreds of vehicles per day, since just 15 minutes are needed to refill a car.
Battery technology and electric grid stability reasons would need to be considered to impement this, possibly installing large batteries at each station.
EVs, there will need to be a strong interdependency between two normally distinct activities, namely “parking” and “re-fueling.” Changing the way we work will be key to taking this on.