Made by Lotus and will do low flying. A saloon available in around 18
months time. Well by, by, internal combustion engine.
- Equiv to 135mpg
- 250 miles range (will be better when more improved batteries are out in a
- 0-60 in 3 secs or so.
Designed, and funded, by IT people, NOT people in the automotive industry -
they wouldn't touch them as their minds are stuck in the past. They got
Lotus involved in the car body design and they will make the car too. This
a mass production car, not a 2 a week job. They have even produced a
A saloon is due in 18 months time. They predict the miles range will be
even better as a new generation of batteries comes in. The man who designed
the cars management system, the key to the whole thing which gives the
range, developed circuitry to extend the life of laptops.
The company is based in Silicon Valley.
It seems like the EV is here now for good. I'll have to buy one.
Not all at once though.
If equiv to 135mpg and range 250 miles that suggests about $4 to recharge
the battery. Assuming 15cents/kWh thats 26kWh stored energy.
As max power is 185kW which assume for 130mph, actual range approx 8.5
minutes or about 20 miles.
All assuming 100% efficiency which of course is crap. I am in UK so someone
check my figures, but they don't stack up from where I am sitting.
The 3.5 hour home charger needs a 70 Amp 220V supply.
70 * 220 * 3.5 / 1000 = 49 kWatt-hours so the stored energy must be quite
a lot higher than 26kWH otherwise you'd be cooking the batteries +
charger if you lost 23kWH in heat.
Without picking through your figures, you probably are right. Max speed
is about power to drag. So going fast is very energy inefficient.
Picking through the specs, the vehicle weight is not quoted,and
acceleration is power to weight - so that'll be another battery-eater.
So that 250 mile range probably requires gentle acceleration and
moderate speed - but there are no concrete figures for the test
conditions - so we don't know.
On the plus side it quotes 1000lb for the battery pack weight, and it
sounds like it's using a single electric motor through a conventional
powertrain. Lotus make a light car - so maybe around a ton kerbweight?
And people from the electronics sector do know a few things about power
management - they're used to doing everything possible to get the most
out of a battery.
That many Li-ion cells must be a large proportion of the price - I
wonder if you get good quality or even hand-matched cells? And how long
before the battery pack has had enough and requires replacing?
Indeed. All valid points.
the discharge rate is not excessive - anything over 20 minutes-to-flat
is not a huge stress for a lithium cell, and that means they can be
optimised for low self-discharge and decent cycle life. At least 100
cycles (20,000 miles) is EASILY obtained, and 500 cycles (100,000 miles)
should be within reach. You wouldn't necessarily need hand matched
cells. The way I'd do it is create plug in blocks each with a
voltage/current/temperature monitor on them feeding a data bus, and
switch em in and out as they got flat, or near overcharging, or too hot etc.
Then at service time, any substandard blocks get swapped out.
The big problem with rechargeable cars is the length of time required to
give a full re-charge. You can fully re-fuel an IC vehicle in minutes. I
can see this being a bigger problem in the US, where people think nothing
about driving hundreds of miles in a day. Re-fueling stops will not
neccesarily co-incide with convenient overnight stops!
I really can't imagine any battery charging process in the near future that
can transfer energy anything like as quickly as pumping hydrocarbon fuel.
The only realistic solution I can see is having standardised battery-packs
which can be swapped for fully-charged ones. But that's fraught with
problems. It makes it difficult for manufacturers to to introduce new
battery technologies, for example. Also, the size and weight make this a
non-trivial problem on the forecourt too. Somewhat akin to doing an
engine-swap every few hundred miles! Also, I imagine it will have consumer
resistance because people will want to own 'their' batteries, and not swap
them for ones of unknown history. Then there's the issue of who owns the
actual cells, and who takes the financial hit when a battery pack finally
gives up. The unfortunate person who happens to have the battery that day?
Perhaps the idea of the manufacturer owning the cells and hiring them will
address this problem.
Certainly an interesting idea.
 An American friend told me this a few months ago: What's a difference
between a Brit and an American? A Brit thinks 100 miles is a long way, an
American thinks 100 years is a long time.
So let's substantially reduce the requirement for battery power / extend
the range, by providing in-transit recharging.
We could have a scheme whereby on the major but low-speed routes in city
centres is provided a network of overhead wires carrying electricity.
A "collector" could be mounted on the roof of a vehicle to connect with
these overhead wires. Consumption could be metered, although nowadays it
would be trivial to have an onboard gizmo that would combine charging by
mile, Ah or kWh, time, duration, position etc with continuous wireless
transfer of data to the pricing administration.
It might not be feasible for all private vehicles to use this overhead
power network, but electric buses, taxis and delivery vans all offer the
opportunity for any specialised driver training required.
On Mon, 24 Jul 2006 12:08:58 +0100, The Natural Philosopher wrote:
Or a less unreasonable 800A per phase 3 phase, or 450A per phase at 440V
That's going to be forecourt technology, with a cable as thick as a
petrol/diesel filling hose!
However one could envisage the forecourt operators and vehicle designers
conspiring together to offer slower (30 - 60 minute, but still faster than
at-home) charging tied to supermarkets, cafes etc so that the punters form
a captive market for the retail offering while waiting for their vehicle
to charge up.
One would expect to pay more per kWH for the convenience (and the
operator's investment in the infrastructure) with the cheaper, slower
option of charging up at home from a more modestly rated home outlet, or
trickle/very-slow charging/topping up from a standard (13-15A-ish) mains
outlet. Of course if electric vehicles acheive a true mass-market there
will be lots of people for whom home charging is simply not an option
since they don't have off-road parking so forecourt charging will be the
Where are you going to do 130mph for 20 miles?
Efficiency overall charge to wheel should be around 90%.
I think you will find the range is cruising at 55mph, or 65mph, or an
I also calculated about 30Kwh is what it takes to achieve this sort of
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