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I've posted my speculation about how GM may evolve the Bolt EV platform in this thread: 2019 Bolt EV AWD.

I think that evolution to a more CUV-like AWD vehicle will appeal to a broad market, but I wanted to follow-up with what I'd prefer GM do with the platform--and that is a more performance-oriented liftback variant, the Bolt EV SS.

The outside appearance would merge the taller, hatchback of the Bolt EV with the lower height and sloped liftback of the Volt. It would still be 5-doors but the both the front and especially rear seats will have less headroom. The car would have lower ground clearance and wider wider tires, to increase handling and grip. The liftback, lower roof, and lower ground clearance would reduce the coefficient of drag from 0.312 down to 0.26 or so.

The battery volume would also be reduced. The 2nd row of the stacked battery below the rear seat would disappear reducing battery volume by 20%. Battery energy density will be improved such that the now smaller battery has 50kW of energy but lower weight and volume. This allows a lower rear seat, saving some of the cargo volume and headroom taken by the rear liftback.

Finally, it has the AWD system I outlined in that other thread, with 140 hp/175 lb-ft motors for each axle and a multilink rear suspension. Here's how the vehicles compare:

2017 Bolt EV
Initial sales: late 2016
Drivetrain: FWD, 200hp/266lb-ft
Battery: 60 kWh
Weight: 3,580 lb
Range: 200+
0-60: <7 sec
Top Speed: 91 mph

2019 Bolt EV SS
Initial sales: 2019
Drivetrain: AWD, 280hp/350 lb-ft
Battery: 50 kWh
Weight: 3,400 lb
Range: 200+ mi
0-60: 5.0 sec
Top Speed: 120 mph

Incidentally, I think this fantasy Bolt EV SS is very close to how Tesla will spec the Model 3.
 

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I think a lot of people will be interested if they manage to improve performance while retaining that 200 + mile range
 

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I like the whole idea of it being a like a Model 3 and this being Chevy, you can bet it will be much cheaper, and to some more trustworthy since they've been around for much longer and have a track record we can depend on. Unlike Tesla that has been around for only so long.
 

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Not sure if the performance is worth the 20% battery reduction. Sounds great but I still want to be able to travel just as far as the non SS model.
 

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Of course you'll have to account for how often you can charge up. Fortunately that problem is decreasing by the year and building up speed. At the least though it will allow you to have moments to let loose. Those that live in the city shouldn't have a problem being heavy on the pedal.
 

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Green and fast. As long as the show meets the go, I think it's a great idea. With batteries and electric motors it should be a simple flip of a switch. Range when you want it and performance when you aren't worried about range.
 

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Green and fast. As long as the show meets the go, I think it's a great idea. With batteries and electric motors it should be a simple flip of a switch. Range when you want it and performance when you aren't worried about range.
Who knows we might even see some tuning brand some out with ECU tunes that unleash more power or lets us do things it wasn't originally intended for.
 

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Not sure if the performance is worth the 20% battery reduction. Sounds great but I still want to be able to travel just as far as the non SS model.
Both specs that were posted up state that the range should remain above 200 miles. Range may have higher standards by then, but at least that is a floor that we can count on.
 

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Good point about the regs, that might be one of the reason for car makers to set the range so high to keep the vehicle relevant for a while as regs change.
 

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Makes one wonder about how much battery tech for cars can jump per year and if power will improve in leaps and bounds too.
Well there is constant development going on in the EV space, things are just heating up, and hypercar makers are already experiencing some of the best EV tech right now, a good indicator of what we can expect to see in the future on a mainstream level with vehicles the average person can afford.
 

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There are several EV racers that use small packs but have high energy discharges for fast acceleration and top speed. But a Bolt EV cannot have faster acceleration AND good EV range. They are opposite uses of energy. So if you want a sportier EV you will lose range.

Another point is the present Li-Ion cells are not designed for heavy power output. You must add a second source of energy storage in parallel that can give incredible power output and that will be supercapacitors. They will take up space and increase cost. So think about what you really want and if you are willing to pay for it.
 

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At this point, people won't be willing to trade the 200 mile range for more power. Maybe in the future but for now manufacturers are going to try and reduce people's range anxiety.
 

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Indeed, you have to be able to sell people on these and allow them to easily see themselves using the product how they already use what i'll replace. Any in-depth thinking is bound to cause them to have lost interest.

What will help them is showing what that range and the power in the battery can get them in real life situations.
 

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If this fantasy Bolt SS ever some out, maybe they can partner up with the Genovation green car company. To managed to do 186.8 mph on a Shuttle Landing Facility in Florida with an electrified Corvette called the GXE.

Probably drained all the power in that short sprint but it's a good example of what is possible.
 

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I doubt that, for the most part it seems GM likes to keep everything inhouse and everything all them without many partnerships or any at all.
 

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I can't see GM partnering with some Green car company. Why would they? They could just do all that R&D themselves instead.
 

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Wasn't aware that they were trying to keep everything in house but I guess that should have been a given since they can afford to do the development themselves.
 

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A 20% battery reduction isn't compatible with "SS" performance. Significantly higher performance requires not only dual motors but more current, which requires more battery capacity. Higher performance also requires a larger battery to achieve a practical range, since aggressive driving will suck the charge down. Given current motor efficiency an SS Bolt would probably need something like 75 kWh to be worthwhile, so add the cost of a second motor, more cells, and the necessary R&D. That's a lot of extra R&D for a model variant that will have relatively few sales.

The current battery has extra unused space for more cells which makes me think they intend to add more capacity as price/kWh drops. Whether they improve performance is an open question but I kind of doubt they will go dual motor since the price is already quite high for the car's appearance and interior furnishings.

If the Bolt remains FWD then there isn't much more low-end performance to be had due to torque steer. The VW GTI is the highest performance FWD on the market and it has about the same 0-60 time as the Bolt (a few tenths faster if an expert launches the GTI). Chevy could improve acceleration at higher speeds but I doubt it's a priority for them since they are already pleased with customer satisfaction levels.

Another point is the present Li-Ion cells are not designed for heavy power output.

No need for capacitors, more current can be obtained from the battery simply by increasing the number of cells in parallel. That's how Tesla get's Ludicrous acceleration, by dropping in a big honkin' 100 kWh pack (Plaid uses at least 200 kWh in the upcoming Roadster).

That's why I think a Bolt SS would require at least 75 kWh, maybe more.
 
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