Hydrogen Fuel-Cells

[Marc-1]

Power eDrive or Hydrogen Fuel Cell?

Hydrogen Fuel-Cells produces energy for the assembled electric motor.
At the (approximately in the year 2000) Frankfurt Motor Show IAA, BMW presented for the first time the 750HL, 750 Hydrogen Fuel-Cell sedan. The BMW guys told me there, that this kind of technology has a lot of issues and factors, unknown to the public.
E.g. is not known that the Hydrogen Fuel-Cell is continuously producing energy that has to be stored. This requires a big Li-ion battery. The Hydrogen Fuel-Cell responds rather slowly to power fluctuations. This requires a big Li-ion battery too, for sudden acceleration or hill climb. For every generated kilowatt hour, the Hydrogen Fuel-Cell produces 1 kWh waste heat.
There are 1%/2% storage loss of Hydrogen each day. BMW found, that in the case of a half filled tank, all Hydrogen may has disappeared completely after 9 days. So it's severely forbidden to park the car in a garage, to preventing an explosion.
You need 56 kWh of electricity, to make 1 kg of Hydrogen ... acc to BMW, the Hydrogen Fuel-Cell of the 5 series GT is identical with the Toyota Mirai one; market launch may be 2020 or later.

 

[Deleted member 25]

Hydrogen Fuel-Cells produces energy for the assembled electric motor.
At the (approximately in the year 2000) Frankfurt Motor Show IAA, BMW presented for the first time the 750HL, 750 Hydrogen Fuel-Cell sedan. The BMW guys told me there, that this kind of technology has a lot of issues and factors, unknown to the public.
E.g. is not known that the Hydrogen Fuel-Cell is continuously producing energy that has to be stored. This requires a big Li-ion battery. The Hydrogen Fuel-Cell responds rather slowly to power fluctuations. This requires a big Li-ion battery too, for sudden acceleration or hill climb. For every generated kilowatt hour, the Hydrogen Fuel-Cell produces 1 kWh waste heat.
There are 1%/2% storage loss of Hydrogen each day. BMW found, that in the case of a half filled tank, all Hydrogen may has disappeared completely after 9 days. So it's severely forbidden to park the car in a garage, to preventing an explosion.
You need 56 kWh of electricity, to make 1 kg of Hydrogen ... acc to BMW, the Hydrogen Fuel-Cell of the 5 series GT is identical with the Toyota Mirai one; market launch may be 2020 or later.

Do you have any source to confirm these very interesting infos ?

 

[Marc-1]

Do you have any source to confirm these very interesting infos ?

My IAA exhibition round tour had led me to Mercedes Benz too. They presented their future car. The Hydrogen Fuel-Cell system was arranged in the sandwich body floor of the A-Class with long wheelbase (which was the one and only reason for the construction of the sandwich body floor). So, the the 750HL I remembered, was a 750 Hydrogen ICE sedan. The BMW guys told me all the reasons (I mentioned in my in my last post) for their decision to present this one instead of the Mercedes all electric Hydrogen Fuel-Cell car.

Anyway, here are some sources:

If operated in a vehicle, the PEMFC stack has an estimated service life of 2,000–4,000 hours. Wetting and drying caused by short distance driving contributes to membrane stress. Running continuously, the stationary stack is good for about 40,000 hours. Stack replacement is a major expense.
...
The fuel cell requires improvements to resolve slow start-up times, low power output, sluggish response on power demand, poor loading capabilities, narrow power bandwidth, short service life and high cost. Similar to batteries, the performance of all fuel cells degrades with age, and the stack gradually loses efficiency. Such performance losses are not visible with the ICE.
Paradox of the Fuel Cell: http://batteryuniversity.com/learn/article/fuel_cell_technology

Parking a hydrogen vehicle or other gas-fueled vehicle in an enclosed structure is a serious safety concern as it can lead to a buildup of the gas. Hydrogen’s tendency to rise and disperse rapidly makes this the only situation in which small leaks can create extremely dangerous situations.
FuelCellHydrogenFuelVehicleSafety.pdf: https://dps.mn.gov/.../FuelCellHydrogenFuelVehicleSafety.pdf