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The Next Leaf Bev with 36KWh battery or 30-40KW REX engine?

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Discussion Starter · #1 ·
Just for my own curiosity really. I'm in the rex camp, if I've got to carry the extra weight of battery's that I don't need all the time, I'd rarther have a 40Kw engine sat in the spare wheel well just in case.
 

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Discussion Starter · #2 ·
Which is why I'd have probably brought an i3 if it had 5 seats :)

What other options would you like?
 

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36kwh battery is believable to me, but I think that means a range of about 105 miles, 160 is very unlikely.
 

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Discussion Starter · #4 ·
Yes that's a good point I agree that they would probably see it as a failure.

I'll have a Pulsar Ev with Rex then please :)
 

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I voted ReX purely because you are never going to be stranded. It may be a PITA to top up a 10 litre tank (that's only about 100 miles, if that) but it's a lovely comfort factor if you can't get a charge. Doesn't matter how big your battery is if there are no working chargepoints.

Plus the ReX approach rather than the "plug in hybrid" approach means your electricity is hauling the minimum necessary amount of unused weight. You also get a free heater so don't need the expensive heat-pump solution to demisting your windows.

I think Edd did some calculations ages ago that you'd only need a 10kW generator to do the trick, it could probably all be kept down to 50kg of excess weight, maybe 75kg with all the cabling. Maybe that's why they dropped a seat - rough equivalent of one passenger :)
 

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I voted ReX purely because you are never going to be stranded. It may be a PITA to top up a 10 litre tank (that's only about 100 miles, if that) but it's a lovely comfort factor if you can't get a charge. Doesn't matter how big your battery is if there are no working chargepoints.

Plus the ReX approach rather than the "plug in hybrid" approach means your electricity is hauling the minimum necessary amount of unused weight. You also get a free heater so don't need the expensive heat-pump solution to demisting your windows.

I think Edd did some calculations ages ago that you'd only need a 10kW generator to do the trick, it could probably all be kept down to 50kg of excess weight, maybe 75kg with all the cabling. Maybe that's why they dropped a seat - rough equivalent of one passenger :)
The i3 REX generates heat from the battery rather than the Ice engine so range is reduced substantially when the heater is used, so not exactly free heat. The heat pump is standard on the Leaf Acenta and Tekna models rather than an optional extra. Plus 5 seats of course!
 

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I voted ReX purely because you are never going to be stranded. It may be a PITA to top up a 10 litre tank (that's only about 100 miles, if that) but it's a lovely comfort factor if you can't get a charge. Doesn't matter how big your battery is if there are no working chargepoints.

Plus the ReX approach rather than the "plug in hybrid" approach means your electricity is hauling the minimum necessary amount of unused weight. You also get a free heater so don't need the expensive heat-pump solution to demisting your windows.

I think Edd did some calculations ages ago that you'd only need a 10kW generator to do the trick, it could probably all be kept down to 50kg of excess weight, maybe 75kg with all the cabling. Maybe that's why they dropped a seat - rough equivalent of one passenger :)
Yeah, 10kw would be enough to constantly drive at 60mph until you ran out of fuel. If you wanted to travel at 70 or 80mph you'd need a bit more!
 

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Does anyone actually know what a 10kva generator weighs, I have a small 5.5kva and it is over 100kg
 

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48kwh would be "hard" right now, it would need physically more space to put cells, most likely with a split pack design with extra cells under the boot floor (lots of space there) or in the engine bay (with either an expanded nose and/or further reduced drivetrain volume or packaging - laying the drivetrain flat instead of upright split fore and aft of the axle would make sense and leave a large are above for more cells.)

30-36kwh would be "easier" because a more energy dense chemistry can probably get us there without increasing cell count. It also creates less of a problem in the marketplace for the 24kwh Leaf suddenly being "worthless". A 30kwh car would have a useful boost in range (20-30 miles more) without doing lots of re-engineering but isn't enough to make the car fundamentally different. I think if Nissan want to make a car with 48kwh or more it will be wearing an Infiniti badge and a higher price tag.
 
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48kwh would be "hard" right now, it would need physically more space to put cells, most likely with a split pack design with extra cells under the boot floor (lots of space there) or in the engine bay (with either an expanded nose and/or further reduced drivetrain volume or packaging - laying the drivetrain flat instead of upright split fore and aft of the axle would make sense and leave a large are above for more cells.)

30-36kwh would be "easier" because a more energy dense chemistry can probably get us there without increasing cell count. It also creates less of a problem in the marketplace for the 24kwh Leaf suddenly being "worthless". A 30kwh car would have a useful boost in range (20-30 miles more) without doing lots of re-engineering but isn't enough to make the car fundamentally different. I think if Nissan want to make a car with 48kwh or more it will be wearing an Infiniti badge and a higher price tag.
My money would be on a 36kWh pack, with ~160miles claimed range, 120miles real world.
I can't see Nissan going the Rex route (not in the Leaf, at least). I'd expect to see some sort of hybrid Qashqai before too long, though.
 

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36 I think is a stretch too far. You'd need new chemistry and different packaging I think. Not that it's impossible to do, just that Nissan won't.
 

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36 I think is a stretch too far. You'd need new chemistry and different packaging I think. Not that it's impossible to do, just that Nissan won't.
You want to put a tenner on that? :)
 

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Discussion Starter · #19 · (Edited)
The other thing about have a rex engine instead of more batteries means you could still use it even if there were no chargers on route. So say a return journey of 170 miles, you'd be able to travel one way on electric & back on fuel, in a purely electric vehicle you'd have to leave it at home.
 

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48kwh would be "hard" right now, it would need physically more space to put cells, most likely with a split pack design with extra cells under the boot floor (lots of space there) or in the engine bay (with either an expanded nose and/or further reduced drivetrain volume or packaging - laying the drivetrain flat instead of upright split fore and aft of the axle would make sense and leave a large are above for more cells.)
I have a feeling that you can't put any battery in the boot floor space as that's crumple zone. Equally for putting it too far up front. Increasing the length could be problematic as the Leaf is already quite a large car for the class (it just doesn't seem like it, until you park next to a supermini and realise that the Leaf really isn't!). Move it up to the Mondeo class and you are really into proper motorway cruisers, which it is never going to be.

I wonder if there is scope to split the drivetrain from the charging equipment (they already did some consolidation there). You could happily put all that gubbins under the boot, some some space behind the motor.

I think you are right that 48kWh would be a stretch too far and 36 will be "hard". I did see a chart somewhere though that showed the Leaf at the lower end of battery density compared with other EVs.
 
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