Speak EV - Electric Car Forums banner
21 - 40 of 48 Posts
Only one problem... I think the combined weight of battery and fuel cell + H2 storage will be the same as a 90kWh battery in 20 years time. And the battery will be cheaper. Eg. At 7% per year average density improvement gets you a doubling of density every 10 years. So the i3 / leaf would double their capacity from 22 to 44 to 88 kWh. I can't see any one needing more than that. And you won't need a rex once you get about 50-70kWh.
I would say you are over guesstimating the growth of batteries. There is no way it is going to follow some sort of Moore's law, Li-ion is already near its theoretical max. We would have to see new chemistries, really reactive [read; dangerous] ones that are not even in the commercial domain yet, let alone proven out in time fit for automotive applications.

And you are also underestimating fuel cells - you can have an air-cooled 5kW unit that fits in your briefcase. That would be ideal as a range extender - if you draw 10kW, 5 from the battery and 5 from the FC, you can happily average 60 and keep going for 4 hours on the battery, 240 miles. That'll do!
 
It's a hybrid.

You could easily argue a Prius is an electric car - it has a battery, an electric motor but maybe brush over the fact it needs fuel adding to make it go. Same as a hydrogen car - it has a battery, an electric motor and needs fuel adding. Perhaps we could have a petrol car running an engine as an electric motor and powering the wheels that way (like a diesel electric locomotive). Would that be an electric car?
 
I lot of people I talk to don't understand the fuel cell tech and think hydrogen is used in the same way as petrol. They look completely shocked when it is explained to them:confused::confused:
 
If the public were asked do you want to drive with Hyrdogen in a tank to make electricity or just drive with batteries storing the electricity then many more may see the BEV light! Hydrogen will be great for buses and trucks. A hydrogen Rex is and interesting concept!
 
It's a hybrid.

You could easily argue a Prius is an electric car
Hybrids have more than one power source/propulsion method I would say. I think the FCEVs are all one type only, that is to say they don't have either an engine or a proper large battery, they just use the fuel cell to power the electric motor.
 
Hybrids have more than one power source/propulsion method I would say. I think the FCEVs are all one type only, that is to say they don't have either an engine or a proper large battery, they just use the fuel cell to power the electric motor.
But then what's an i3 Rex? I think it's a plugin hybrid, as is the volt, since they both have two types of fuel.
 
Tell you what a hydrogen car definitely isn't though, a plugin car, and I still feel that's its biggest failing.
 
  • Like
Reactions: RoyOb
Tell you what a hydrogen car definitely isn't though, a plugin car, and I still feel that's its biggest failing.
It very much feels like a lot of effort to keep hold of "the old ways" whereas plugins seem to offer a real alternative (several alternatives) to the old top-down, chained to the pumps service of "old".
 
Hybrids have more than one power source/propulsion method I would say. I think the FCEVs are all one type only, that is to say they don't have either an engine or a proper large battery, they just use the fuel cell to power the electric motor.
But they have a 'small' HV battery the same size as the non plug in Prius. Sometimes it runs off that small battery when the fuel cell isn't up to temp or under high load, and sometimes it doesn't. Sounds just like a Prius to me.

So it's still a hybrid ;)
 
It's a hybrid.

You could easily argue a Prius is an electric car - it has a battery, an electric motor but maybe brush over the fact it needs fuel adding to make it go. Same as a hydrogen car
Possibly. Although you could argue that an FC is actually a hydrogen-oxygen battery, in the same way there are several potential 'new techs' that are 'oxygen' batteries, namely zinc and aluminium batteries.

In fact, dwelling on my comment about purity and contamination of air, and that an FC might actually need to carry around its own O2 store too, if it were to store both H2 and O2, then it might also be designed to be 'rechargeable' through electrolysis of the water emissions it produces.

...Sometimes it's too easy to get caught up in irrelevant categorisations.
 
Possibly. Although you could argue that an FC is actually a hydrogen-oxygen battery, in the same way there are several potential 'new techs' that are 'oxygen' batteries, namely zinc and aluminium batteries.

In fact, dwelling on my comment about purity and contamination of air, and that an FC might actually need to carry around its own O2 store too, if it were to store both H2 and O2, then it might also be designed to be 'rechargeable' through electrolysis of the water emissions it produces.

...Sometimes it's too easy to get caught up in irrelevant categorisations.
Electrolysing your own waste is a great idea, and sort of completes the virtuous circle.

Except if we refer back to this guy:
Text Yellow Parallel Line Diagram


Each kwh from your plug is only going to be .32kwh at your motor controller, it would cost more than double what a BEV costs to refuel.
 
Anyone heard about lithium polymer batteries for automotive use? I heard they are in trials and expected to double range, increase cycling and be safer with no short circuit flashing possible. Just so much stuff when you google can't see real news for the noise.

Wiki has a bit... but it's the second type true polymer electrolytes that I heard were in testing in EVs, not the sort currently available for model cars and phone batteries.
Lithium polymer battery - Wikipedia, the free encyclopedia

Edit... a bit more googling got me the sort of speculative info with more details...

Lithium Polymer Batteries

Edit - I forgot sulphur was mentioned too!
Sound like something along these lines - whether "testing for EVs" mean in a physical car, or just running EV like charge discharge cycles I have no idea.

A lithium-ion sulfur battery using a polymer, polysulfide-added membrane : Scientific Reports : Nature Publishing Group

The other thing I heard was high charge rates. <10 minutes for 60+kWh. If it's all true and due for next gen EVs then H2 will quietly slip away.
 
<10 minutes for 60+kWh
That will be a 360kw supply required (3 superchargers at plugged into one car). I think there would need to be some local battery storage to deliver that charge rate or the supply upgrade costs could get out of control.
 
Exactly - I'm not sure I'd want to be investing £50k and up in 50kW class DC chargers at the moment if these are just around the corner. There might only ever be 50,000-100,000 cars that will need to use them. The next gen of cars will do door to door and everyone will want one, so it's domestic supplies that will need upgrading for faster overnight recharges. Maybe a few strategic locations for 400kW DC CCS units for long daily distance drivers. 300 miles+.

That's all assuming these lithium sulphur polymer batteries don't cost £50k each!
[edit] I keep forgetting not everyone has an off street charging facility.
 
My gut feeling is that someone who has silly-long days (say, arrive home at 2100 and leave at 0500 the next day) would still be able to squirt 7kW * 8 hours = 56kWh into their car overnight on an existing 32A charger. 11kW is about the max doable on single-phase which would give them 88kWh.

56kWh equates to roughly 180 miles of driving, by which point you should either have arrived at your destination, or a short stop for a 400kW blast of range is probably welcome while you sort yourself out (shave, coffee, breakfast and t'other).

88kWh is nearly 300 miles - does anyone do that one-way, every day?
 
21 - 40 of 48 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top