Chrysler introduces Pacifica plug-in hybrid minivan; 80 mpge city, 30-mile AER
Ford launches ambitious FordPass product as element in its strategic transformation to mobility company

Chevrolet releases more details on Bolt drive unit and battery; one-pedal driving

Hard on the heels of the reveal of the production Volt EV at CES 2016 in Las Vegas earlier post), Chevrolet used the North American International Auto Show (NAIAS) in Detroit to release additional details on the battery and drivetrain of the new BEV. Engineers developed the Bolt EV’s propulsion system to offer more than an estimated 200 miles (based on GM estimates) and a sporty driving experience.

The Bolt EV’s drive system uses a single high capacity electric motor to propel the car. The engineering team designed the Bolt EV’s electric motor with an offset gear and shaft configuration tailored to meet efficiency and performance targets—most notably more than an estimated 200 miles of range. The motor is capable of producing up to 266 lb-ft (360 N·m) of torque and 200 hp (150 kW) of motoring power. Combined with a 7.05:1 final drive ratio, it helps propel the Bolt EV from 0-60 mph in less than seven seconds.

Image

Power delivery is controlled by Chevrolet’s first Electronic Precision Shift system. This shift and park-by-wire system sends electronic signals to the Bolt EV’s drive unit to manage precise feel and delivery of power and torque, based on drive mode selection and accelerator inputs. A by-wire shifter requires less packaging space than a traditional mechanical shifter, resulting in more interior space and improved interior layout.

Having more than 1.3 billion miles of EV experience from the Chevrolet Volt helped Bolt EV battery engineers and strategic partner LG Electronics to develop an all-new cell and battery pack to offer more than an estimated 200 miles of range. Battery system preliminary specifications include:

  • 60 kWh lithium-ion battery pack
  • 160 kW peak power
  • 288 lithium ion cells
  • Five sections
  • 10 modules
  • 96 cell groups – three cells per group
  • 960 lbs. (435 kg) total weight
  • 285 liters
Image

Image

You usually have a battery cell that delivers either the desired levels of energy or power, but not traditionally both. With this cell design and chemistry we were able to deliver a battery system with 160 kilowatts of peak power and 60 kilowatts hours of energy.

—Gregory Smith, Bolt EV battery pack engineering group manager

The battery uses active thermal conditioning, similar to the Chevrolet Volt, to keep the battery operating at its optimum temperature, which results in solid battery life performance. The Bolt EV battery will be covered by an 8-year/ 100,000 mile (whichever comes first) limited warranty.

Inside the battery pack—which spans the entire floor, from the front foot well to back of the rear seat—is a new cell design and chemistry. The nickel-rich lithium-ion chemistry provides improved thermal operating performance over other chemistries, which requires a smaller active cooling system for more efficient packaging. The chemistry allows the Bolt EV to maintain peak performance in varying climates and driver demands.

The cells are arranged in a “landscape” format and each measures in at only 3.9 ins. (100 mms) high and 13.1 ins. (338 mms) wide providing improved packaging underfloor. The lower profile cell design enabled the vehicle structure team to maximize interior space.

The battery system is mated to a standard equipment 7.2 kW onboard charger for regular overnight charging from a 240-V wall box. A typical commute of 50 miles can be recharged in less than two hours. Bolt EV also features an optional DC Fast Charging system using the industry standard SAE Combo connector. Using DC Fast Charging, the Bolt EV battery can be charged up to 90 miles of range in 30 minutes. Outside temperatures may affect charging times.

Image

Regen System Provides One-Pedal Driving. Regenerative braking has become more than just a tool to boost range, it’s also transformed into a feature that can provide an improved EV driving experience. The Bolt EV features a new regenerative braking system that has the ability to provide one-pedal driving.

Through a combination of increased regenerative deceleration and software controls, one pedal driving enables the vehicle to slow down and come to a complete stop without using the brake pedal in certain driving conditions.

When operating the Bolt EV in “Low” mode, or by holding the Regen on Demand paddle located on the back of the steering wheel, the driver can bring the vehicle to a complete stop under most circumstances by simply lifting their foot off the accelerator, although the system does not relieve the need to use the brake pedal altogether.

Operating the Bolt EV in “Drive” mode and not pulling the paddle while decelerating delivers a driving experience where usage of the brake pedal is required to stop.

Comments

electric-car-insider.com

Really glad to see the strong regen / electric braking feature. Further evidence that Chevy has been listening to customers and "gets it".

Kudos to the Chevrolet Bolt team.

Account Deleted

Same price as the Leaf and the e-Golf but twice the battery and twice as powerful at 160kw peak. I really don't see any market for the e-Golf and the Leaf when this Bolt arrives.

I am glad to see GM stepped it up on engine power. That means it cannot be compared to a 15k USD gasser. Now it is more like a 20 to 25k USD gasser. So the Bolt is still too expensive to become a mass market car. What matters is how many they will sell. Hope that 24 and 30kwh BEVs will be history in 2017. Make the Bolt with an option for an OTA upgradable autopilot system and it will be even more interesting for the environmentalists that are buying this car.

kalendjay

As regenerative braking only recovers 25-35% of the torque energy, it would be great if the Bolt were smart enough to coast to a lower speed allowing the driver to speed up mildly under the most practical circumstances. A smart driver will do just that at stop signs, yield signs and stop lights. I try to do that I would say 10 to 15 car lengths before an intersection, which is about 3X the recommended car length paractice needed in a 25 to 40 mph zone. Can cars educate drivers?

electric-car-insider.com

@kalendjay My Ford Focus Electric does have a dashboard display "braking coach". My Model S has one pedal driving and it sounds like the Bolt has something very similar, which will
accomplish what youre describing.

Thomas Pedersen

The chassis illustration looks remarkably like there is an ICE in the front. What is all that 'crap' surrounding the e-motor?

Does air conditioning and brake lines really take up that much space and wiring..?

Btw.: I wonder how much more expensive it is to package the battery with the hump at the end. Obviously, there was not enough space length-wise to do without it. But if it costs very little to make the battery higher in the space under the rear seats where the gas tank normally resides, then it bodes well for increased flexibility for the car makers to install more capacity, once battery costs allow it.

Did you notice: ~1000 lbs battery pack. Yikes! (I am aware that the weight of the car is less important - efficiency wise - in a car with brake regen)

Brian Petersen

That "crap" will be the motor drive (the variable-frequency electronic unit), the battery charging unit, a motor-driven air-conditioning compressor with its own motor drive, the air-conditioning condenser with cooling fan, the battery temperature control coolant pump and radiator, plus whatever is necessary for operating the car's power brakes and power steering, and there will be a 12-volt power supply and probably a small conventional battery for operating the vehicle's lighting, windshield wipers, HVAC, and general electronics, which are all still 12-volt systems. Everything driven by the engine in a normal car has to have its own electric motor. It all takes space. Power electronics require thermal management which limits how much they can be shrunk down and how tightly they can be packaged.

It looks like a lot in the cutaway because of how densely it's packaged, but the nose of this car is quite a bit more compact than that of a Chevrolet Trax, which is its closest platform-mate.

This car is indeed no lightweight. No EV with decent range will ever be.

Dr. Strange Love

It is a city car. I think that we could own a city car if the AC compressor and headlights can be engaged 100% of the time and the vehicle is still able to achieve the 200+ range. My wife will never disengage the AC compressor. Like the Geico commercial, "...it is what you do." She also travels during morning/evening darkness, so the Head Lights will never be off.

I don't think Electric Vehicles are for commoners. You cannot expect commoners to think.

Dr. Strange Love

We nearly purchased a Toyota Avalon Hybrid over this past Holiday, but our attention was directed away from this choice for several reasons. My wife and I decided that an affordable/efficient All-Wheel-Drive Gasser platform was a better option. I don't like to plow our 1/4 mile driveway when it snows less than 1 foot. (I would rather read and watch television in my closet.) We are going to acquire a Subaru Outback instead.

I realized also that the Economic Efficiency of the Avalon Hybrid and Gasser would be a Wash (on-Par using EE Econ 101 principles) because my wife Never Disengages the AC compressor and the Lights would also be on constantly, no exceptions.

Brian Petersen

Electrically-driven air conditioning systems don't have to be simply "on" or "off". The motor can be driven through a VFD which matches the capacity of the compressor to the demand, to minimize electrical draw, and it is virtually certain that this car will have thermostatic climate control. 'Course, that motor and the VFD account for more of the gizmos under the hood.

This will not help the person who runs the air conditioning and blower speed on "max" no matter what ... but this car does have a display available to show how much power demand that climate control is accounting for. The information is available. If people choose to ignore it, that's their problem.

I'm not 100% sure, but I think this car has LED headlamps and I know it has LED taillamps, which cuts power demand. GM has done what they can here.

Dr. Strange Love

Yea. She likes the background noise of the fan, and dry air, irrespective of the climate outside. It is a given. I suppose Small bits of energy usage information via the accessories could help to steer how the commoner can improve their energy usage profiles. Commoners in general do have a conscience.

I think Accessory Energy Information Maps and Displays should be required in all cars sold. Climate Control, Audio, ... they all require power.

Sirkulat

Dr Love, ahem et al, the EV offers a backup power supply.
The PHEV offers smaller battery pack that matches more evenly
to the modest PV arrays regional utility grids accommodate:
PHEV+PV more ideally than BEV+PV.
BEV+PV draw-from more than supply-to grids, get it?

Approximate 100 Tesla vs 1500 Prius households.
Which? -driving least while developing short-trip economies?
Better BEV heads better think again, darn it.
Hydrogen fuelcell also loses to hybrid PHEV using hydrogen at lower pressure
thus wider distribution and co-generation with important bio-fuel systems.

You gotta be kidding me. So tired of this un-finished debate.
Self-driving car tech is nonsense.
Save some safety features, sure.
Give UP on empty cars everywhere,
NOT crashing into pedestrians and other cars
while increasing traffic, without casualties?
Simpler EV more widely distributable is unquestionably
the PHEV+PV option.

So anyway, Dr Strangelove, translation:
You may miss an opportunity for a cheap 'portable' emergency lifesaving power supply for whole communities, at each other's rescue,
with a portable backup power supply system!
Yew jus thinkabodit now yahear?

I helped restore SanDiego River/estuary 15 years ago anniversary party coming up. Almost clean enough marsh for a fishery, in this century sans chemical fertilizers. Done good there. High Speed Rail off to a good start, myopinion.
VersedRail practioner design/engineer draftsman.
also known as:

THE SEATTLE CIRCULATOR PLAN (2002-present)
"Plan B for BERTHA"

Both plans still options callously rejected by know-it-alls taking conference with other know-it-alls in high-tech circles, neither thinking the other at tad incorrect while spending money on Seattle with worst new rail starts worst streetcar system. Whom influence whomever on whatever is going on here?
Something like that? Just remember PHEV+PV is best.
also remember, Bertha is perhaps possessed?
PREDICTION: 'amplifies' destructive earthquake forces
suddenly dislodging sinkholes, building collapse.
Few offer the least concern this predicted analytical conclusion is incorrect.

I'm scared like the Black Rabbit from Watership Down.
I see the warren hole entries plugged and the asphixiation of that scene from toppled buildings I'm convinced will happen BECAUSE of the bore underneath wildly transmitting waves of vibrations along its length with probable water redistribution channelling under destructively high pressure while shaking disturbs foundations: Potential collapse in that sense is very high risk. There I said it.
Yet. Haha/Hoho seattlers casually comforted have other worries.

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Working...
Your comment could not be posted. Error type:
Your comment has been posted. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.

Working...

Post a comment

Your Information

(Name is required. Email address will not be displayed with the comment.)