The options discussed are batteries under the floor vs. mid-rear batteries behind the driver in a two-seater... but these still require lots of cells, and in the absence of other innovation, still therefore presumably carry a major weight penalty vs. ICE, as with all current EVs?
The direct comment from Lotus comes closest to providing some details ("...significant weight savings have been achieved throughout... for example, by utilizing the vehicle structure as the battery enclosure, having an integrated EDU, eliminating subframes and optimizing the multi-link suspension components.") - but this is essentially fairly standard vehicle engineering, and doesn't innovate around the weight of the battery at all.
(I'm not being contrary here - FWIW I own both a Lotus and an EV - but this just seems like weak journalism from a PR release.)
It would be nice to see a track focused version with half the battery capacity. Take advantage of the reduced pack volume and shorten the wheelbase for additional weight loss, now the weight can be on par with an ICE Lotus. RWD with CoG behind centerline and tighter polar moment than an Elise on top of EV torque sounds like an absolute handful; call it a Evropa and have some fun at the local autocross!
In normal driving you accelerate to highway speeds and then coast, or you're in city traffic and benefit from regenerative braking.
On a track, you brake late on purpose because it's faster, but to stop that fast you have to rely more on traditional braking and can't recover the energy. Then you immediately want to accelerate back to high speeds again.
If you put a small battery in an electric track car, it would be flat in ten minutes.
Next year they’re supposed to increase power output to 350kW, which is comparable to a Model 3 Performance. Of course Formula E cars are much lighter, so acceleration and handling are far better than the Tesla sedan.
To brake as fast as the traction limit on the tires, which is what you get from disc brakes, you would need four wheel drive and then bigger than normal electric motors and everything else to be able to absorb that much power that fast.
And then the battery would get really hot, especially if it was small.
Or lithium-sulfur batteries for a battery pack that weighs less:
Or just go for battery swaps:
Perhaps thermal management could be somewhat opened up to the driver with short "sprints" possible, to add some more driver involvement to the experience.
I’d be very happy with a light weight EV Miata that went 0 to 100km/h in under or around 4 seconds. Not Model S Plaid or high end 911 fast, but still by far the fastest production Miata.
There's a full build series too by the company that made it. I think £20k was mentioned as the cost of the conversion kit if they were to sell one. 120 miles range.
I've mostly been keeping an eye out on the aircooled VW conversions (or that EV 1968 Mustang on youtube).
It'll really get interesting when you see more from-scratch cars that don't have the ICE history built in. There are a lot of changes that could be made in design. If the government didn't love to get in your business so much, maybe there could be a world of street-legal EV karts.
Many are still on lead-acid batteries (36V or 48V) but you didn't specify battery chemistry. :)
Tesla's approach seems to be to optimize their cells for energy density rather than power density. They can do that because the packs they use are huge. On the other hand you have relatively small batteries that go in hybrids that are optimized for power density.
I keep wondering why we haven't seen an EV Miata, but you'd probably end up with a small, 4000lb car.
Lacking significant battery improvements, I'm thinking the electric F150 is going to be the game changer in all this.
The main issue is batteries. They could either make a light EV without much range, or make a long-range EV that's quite heavy. Placement's an issue too. If they put the batteries in back under the trunk, they'll have too much weight in the rear causing it to spin out on corners. If they put it under the middle of the car like in most modern EVs, it'll make the car taller and look very un-Miata like. Best case is probably to put most of the battery in the front where the engine was, but I suppose that might be a safety issue (it could be crushed in a collision).
I think an electric Miata will happen eventually, but probably not until Mazda can buy cells that are in the 250-300 watt hours per kg range.
(Personally I would love to see an EV Miata with a manual transmission, but that's probably not going to happen.)
Mazda sells a decent number of automatic Mazdas each year (24% of softtops, 48% of hardtops in 2018-2019 according to auto blog), so people are buying them. The reason to buy a hypothetical electric Miata? Same as for any sports car - it's faster than yours, or at least as fast I can afford.
Whether there's a market for them, I can't say, but if someone doesn't understand the existing market for an existing car, I'm extremely doubtful of their predictions about a hypothetical new car in that niche.
Of course it comes down to personal taste, but I can’t understand why you’d buy a “fun car” but strip away all the things that make it fun. There are much better alternatives at that point.
I don't expect Mazda to make a manual transmission EV Miata but it's something they could do if they really wanted to.
Really my own guess is that the manual trans will continue on the way out due to emissions law if nothing else (and lack of interest). Modern cars have little visceral interest in any case, probably better to buy a hemicuda with a stick or a Cobra kit.
From an environmental standpoint this seems like a step backwards. It can be cost effective to replace entire damaged engines and transmissions even in older vehicles. People are keeping cars for longer, currently the average is over 8 years.
So my commuter car is a cheapie Yaris ICE not EV. Its lead acid battery lives on a shelf attached to the frame, kind like a body on frame by analogy, except instead of bolting a car body to the frame they're bolting a battery shelf to the frame. If they ripped out the battery shelf and embedded a shelf directly into the front quarter panel of the body, then theoretically the car would be a little lighter. Its probably not worth it for a small lightweight lead acid battery. Giant EV battery, on the other hand 5% lighter might be a lot of weight...
Maybe a more intuitive way to understand the difference between a unibody type design and a body on frame design, is to look at old pickup trucks and you can rip the pickup bed off the frame and the truck works fine because the wheels and brakes and all the parts attach to a frame, so a bed-less pickup truck is just a pickup truck without a bed. Now if you rip off the back of a unibody car the entire back of the car would literally disappear because there is no frame, the frame is the body. Like the suspension parts attach to the body. There is no separate body and frame, there's just "the back of the car".
So one way to build a EV is to convert an existing chassis by bolting big battery pack "boxes" onto the frame. There exists a frame of a car and you bolted boxes of batteries to it as an addon. But a lighter way, which takes a lot more engineering, is building the battery "boxes" into the frame itself; there is no separate battery box there's a compartment in the frame that holds the batteries. You can't replace the battery "box" or the frame separately because they are not separate they are the same piece of metal. Much more engineering, much lighter.
I would imagine you can replace the batteries just as easily in a unibody EV as a body-on-frame EV. But you can't replace the rusted out battery box on a unibody EV because there is no separate battery box, its engineered into the frame.
The biggest disadvantage of unibody designs is everything is embedded in everything else so in a body on frame car a minor fender bender you remove and replace part of the body. But with a unibody the whole suspension and drive train gotta go too. To replace EV battery in a body on frame design you simply remove the battery from the frame. In a unibody system there might be a lot more labor hours maybe you gotta remove all the wheels and doors and seats to yank out a substantial chunk of the middle of the car.
The first thing that concerns me about this layout is that it looks like the "Chest Layout" with the batteries mid-mounted in that tall trapezoidal shape will significantly raise the center of mass. I've found that this almost inevitably results in worse handling performance, unless offset. Of course, if this somehow achieves far lighter overall weight than a "Skateboard" layout, it could still be a winning design (but we don't know that yet).
Maybe it is a matter of getting a good compromise between wheelbase, drag and center of gravity height?
Update - more on that here:
Edit: thanks for the additional link
There’s also an emotional component in the difference in perception of driving at 250 Km/h on a BMW 750 or in a Lotus where your seat is hugging the road under you.
The biography "Colin Chapman The man and his cars" by Jerry Crombac is the got to read for this topic. BTW., Crombac is a legend in sports journalism in his own right.
Not just featuring in the opening sequence, but indeed symbolic of the entire show. A quirky, agile stand-out from the crowd that represents freedom and individuality, yet in the end is still imprisoned to follow the same roads as everybody else.
I got to spend some time at the Lotus factory in Hethel when I was 16 doing work experience. Was definitely an interesting thing to see and experience. I apologise to anyone who ended up buying an Elise with a pedal box that I assembled.
Of course, I can understand the complaint that such a machine, superior in performance as it may be, may lack character...
I'm trying to enjoy myself, not go to jail.
I’ve never heard anyone say this except people who aren’t auto enthusiasts…
Think of hypothetical scenario where EVs were the norm first. I don't think EV people would consider switching to ICE as increasing fun: much more complex, louder, hotter engine with worse torque that needs extra hardware and operations to avoid slowing you down.
The noise and gear shifting is only associated with power/speed/fun because that's how cars used to work.
I didn't know that! Thnx.
Also Tesla, just likes vertical integration in general. I believe they control their whole battery manufacturing pipeline.
I can’t remember the last time I drove more than 200km in a single trip in my Miata, and it’s my daily driver.
A Tesla model S battery is something like 1200 pounds. The entire car weighs something like 4500 pounds. If the range is 370 miles but I personally never drive more than 40 miles round trip to work, I could rip out 90% of the battery while maintaining 100% of the car's functionality to me, so I could drop the 0 to 60 time to possibly under 1.5 seconds due to lower weight. Should see a similar boost in handling performance.
Out at the track I could trivially outperform any stock unmodified Tesla S with the simple mod of ripping out 90% of the useless-to-me batteries. Its not like I ever voluntarily sit in a car for 370 miles at a time, LOL.
I wouldn't be into the likely staggering effort to rip out the batteries, but I know hot rodder car mod type people who would be all into shaving off 25% of your 0-60 time.
Maybe, if "Everyone" had EVs, and I bought a second hand used car with a dead worn out battery, I would intentionally replace the giant 400 mile battery with a mere 40 mile battery just so I can gain incredible performance, AND the battery would be 90% cheaper than a full size battery, a win-win for me...
I know its a stereotype of boomers that they have severe range anxiety and can't buy a car unless it can drive more than 20 hours continuously between "refuelings" but by the time "everyone" drives EVs the boomers will be gone, most likely. I'm not going to miss "range anxiety" complaints about EVs.
If only this were the case. 2 seconds is pretty much the hard limit for a street car with the best tires you can get. Anything beyond that requires those giant funnycar tires that deform on acceleration to add grip. Or a rocket.
> Maybe, if "Everyone" had EVs, and I bought a second hand used car with a dead worn out battery, I would intentionally replace the giant 400 mile battery with a mere 40 mile battery just so I can gain incredible performance, AND the battery would be 90% cheaper than a full size battery, a win-win for me...
I think, as other commenters have mentioned in this thread, that having a lot of cells isn’t really negotiable. You need both voltage (cells wired in series) and amperage (cells wired in parallel) to push the car forward. If only it were so simple. The trade off with fewer cells is pretty much necessarily performance and range.
We're not going to get mass market EVs due to range anxiety and thats not going away until the boomers go away, just kinda how it is.
Thinking out loud. At what point are legislative controls ever put on car performance, if ever? They've kind of hit the limits on ICE engines with the Hellcat Dodges (for example) but there's no reason an EV couldn't have power to weight ratios that are actually dangerous.
So what happens when you can buy a street-legal F1 car?
Yes there is - the vastly more energy-dense fuel used by ICE cars.
The Hellcat Dodge's power to weight of 318 hp per tonne puts it more in the soccer mom category.
The Caterham 7 620, with a 2-liter engine, gets 500hp per tonne, and that's half of what some of the exotic supercars have.
For reference, a Tesla has around 350 hp/tonne.
I think your perception of what qualifies as motoring performance is sadly lacking.
lol. I think you'd be surprised.
Mostly I'm referring to the mass-produced engine itself here, not the car. After all, we live in a world of 1000 BHP turbo LS engines stuffed into old Ford Fairmonts turning single digit quarter miles.
Having said that, at what point is there legislative pressure to limit new cars. JDM is an existing model.