2021 Ford Mustang Mach-E development challenges
Ford’s first BEV on a new and dedicated EV platform has permitted the Mustang Mach-E development team to take full advantage of the integrated chassis. (Ford)

Ford engineers charged with a blank EV slate for the all-new 2021 Mustang Mach-E

Ford’s first dedicated electric platform speaks volumes to the challenges and opportunities facing development of a state-of-the-art EV.

The 2021 Ford Mustang Mach-E is an all-new vehicle. It’s Ford’s first dedicated battery electric vehicle (BEV) and it’s built on an all-new electric vehicle (EV) platform. If that wasn’t enough pressure on its development team, the Mach-E also leverages the Mustang nameplate traditionally reserved for iconic sports coupes, and serves as a technology flagship debuting a host of new features to expand convenience and safety. One of the lead engineers has likened it to simultaneously engineering an EV, a cellphone and an SUV.

“You're delivering the vehicle, that's old-school stuff, we created that at Ford. Now we've got to deliver the new-school stuff too,” explained Robert Iorio, vehicle engineering manager for the Mustang Mach-E. “Expectations of customers are that we have a cellphone on wheels. The customer expects flawless execution of integrated software. That’s halfway to entry with the BEV, because the customer is buying technology, buying the BEV – and they're buying a Mustang and an SUV.”

With first deliveries expected in late-2020, the Mustang Mach-E is a 5-passenger, 4-door SUV available with rear or all-wheel-drive (AWD). The all-new EV heralds the point where battery power-density and cost are permitting affordable “full-range” EVs for popular vehicle segments. Advancements aside, the battery pack still dictates not just the size of the vehicle, but a host of chassis and aerodynamic parameters optimized around it.

Electrified experience
The Mustang Mach-E is not Ford’s first horse at the electrification rodeo. Ford launched its Escape Hybrid in 2004 and its Fusion Energi plug-in hybrid in 2013. It was one of the first manufacturers to fully embrace lithium-ion battery technology, is on the fourth generation of its Power Split hybrid transmission and recently launched its longitudinal-engine MHT hybrid system for trucks and SUVs. The Focus Electric, Ford’s first for-sale production BEV (1998-2002 Ranger EVs were lease-only), began production in 2011, based on the existing Focus platform.

“We have more than 2,500 active patents among our 1,000 engineers,” explained Sue Hong, engineering manager at Ford’s Electrified Powertrain division. “Our motors from Gen-1 to Gen-4 have gotten smaller each year to provide a better package within the vehicle. From the hybrid learnings, the battery is a pouch cell we’ve optimized to make it more power-dense and provide the mileage. We’ve optimized and worked with our suppliers to provide the capabilities Mach-E is looking for.”

Over the last decade, Hong noted, improvements in battery energy density have been significant. “The range on that Focus was only 115 [miles] versus the 300 we have targeted for the Mach-E, which makes this battery a lot bigger, 33 kWh versus 98 kWh for the long-range Mach-E,” she said. “The weight of the Focus EV battery was 300 kg versus 600 kg in the Mach-E.”

A dedicated EV platform also creates packaging benefits that were compromised when utilizing existing, ICE-based platforms. “In our previous generation, we had to package our batteries in the trunk, like the Fusion. It took a lot of the cargo space away,” Hong said. “This vehicle, we actually have our battery as part of the platform, so there's lots of space in the trunk, the cargo area and in front. Those are the lessons learned going from a hybrid, to a Focus-style BEV to the Mustang Mach E.”

Engineering around the battery
The 2021 Mustang Mach-E uses permanent-magnet motors in RWD or AWD configurations, powered by the standard (288-cell; 75.7 kWh) or extended range (376-cell; 98.8 kWh) lithium-ion battery pack. The battery pack is waterproof and liquid-cooled to improve charging times and performance in extreme weather, with extended-range packs targeting a 300-mile (483-km) EPA-estimated range for a RWD Mach-E.

The pouch-type cells will be produced by LG Chem at its plant in Wroclaw, Poland, the same line producing cells destined for Ford’s electric Transit vans. The Mach-E will be assembled at Ford’s Cuautitlan, Mexico plant just north of Mexico City, and the company is expecting to build 50,000 of the EVs in the first 12 months of production.

Battery technology will continue to advance, but as an OEM going to market now, Ford’s engineers must work with available resources. “Given where energy density is, when you want to do a long-distance BEV, that pretty much defines the size and the mass of the vehicle,” Iorio explained. “If you look at vehicles around 300 miles [range], your overall length, dimensions and mass is probably a little larger than you would want. Our key goal with Mach-E is making the vehicle feel as agile as possible.”

When it becomes available in the summer of 2021, the top-spec Mach-E GT Performance package is expected to route at least 459 hp/612 lb-ft (342 kW/830 Nm) through its AWD system and reach 60 mph (97 km/h) in less than four seconds. “Clearly, there's the advantage of performance – obviously, the launch is quicker,” Iorio noted. “But with a low center of gravity, you're able to provide this agility, and overall, a directed steering that is much improved. Part of that is in the stiffness of the vehicle, so it responds much more quickly, and part of that is how we tune the steering and choose our tires so that it handles quicker.”

The Mach-E features a new independent multi-link rear-suspension and is one of the first Ford production vehicles to be tuned by the Ford Performance team utilizing its racing simulator in North Carolina. “We used our NASCAR simulators in Charlotte,” Iorio noted. “We took multiple trips down to the Ford Performance Tech Center, where we drove the vehicle on the simulators with our team to make decisions on our suspension tune to again compliment the low CG.”

The Mustang Mach-E will provide owners with three driving modes Ford calls “experiences” (Whisper, Engage and Unbridled), designed to alter vehicle personality, incorporating metrics such as steering feel, ambient lighting, mode-specific instrument-cluster animations and vehicle sounds tied to driving behavior. “Because it's an EV,” Iorio explained, “the overall feel can be tuned with experiences that have sound injected in the car and graphics that link to your longitudinal and lateral acceleration.”

Managing aero efficiency and design
With an EV, the real challenge is balancing performance with battery range. “On the vehicle level, we look at kilowatt hours per mile,” Iorio said. “It all comes down to that, because that's how much energy you’re storing on the car.” Aerodynamics is a key metric for efficiency, Iorio explained. “We have active front grill shutters on the Class-A surface. When we made that decision, it was, ‘How many kilowatt hours per mile do we save to have the grille shutters out front?’”

According to Iorio, each aspect of the design falls under the same scrutiny. “We looked at aerodynamic wheel covers, the height of the car, and even the profile of our tires. We try to keep our tire profile smaller, that was a trade-off,” he said. “But we had a low center of gravity and this new rear suspension, so we knew we could have a little bit narrower tire and still have the required grip, performance and handling.”

“In good systems-engineering fashion, we have to balance the shape of the car that we want, with frontal area, rolling resistance and drag in particular, then all the rest of the losses on the car,” Iorio said. “We focused a tremendous amount on frontal area and drag. We used a moving-ground-[plane] wind tunnel exclusively. We went to the tunnel with our clay designers multiple times, working on every square centimeter. Part of that gets into our trades with the roof height, some of the sculpting around the front, and the rear in particular.”

“Those cascades were very important,” Iorio continued. “Start with the shape and then get into the efficiency of the driveline and your wheels in particular, then move into overall mass efficiency. We had to make a tough choice when we made the decision to move the front wheels out to provide this proportional perception of a long hood. I think we moved them 20 mm, but that's meat and potatoes in terms of weight when you add width or wheelbase. It breaks your heart as an engineer – but you have to work so the car looks amazing.”

An EV also requires an NVH rethink, with a noise-masking ICE powertrain no longer available as part of the soundtrack. “In terms of sound, we have to rebalance it,” Iorio said. “You have the wind, the road and powertrain, and you want those to come up in unison. You have to retune how, when you accelerate, the powertrain, wind and road come in equally.”

Technology flagship
The Mustang Mach-E will offer the standard host of advanced safety features, including cross-traffic alert, pre-collision assist with automatic emergency braking, post-collision braking and reverse brake assist, much of it now powered by the Intel-owned, and new long-term supplier Mobileye’s EyeQ computer chips and software. An updated adaptive cruise can automatically resume after coming to a complete stop in heavy traffic for 30 seconds (previously three seconds). A new blind-spot detection feature can nudge the wheel after a visual alert if it senses an unsafe action, and a new Road Edge Detection feature provides alerts on roads without lines or a clear edge.

The Mach-E also will offer a new Intersection Assist feature that employs camera and radar sensors to detect oncoming traffic while attempting to turn left. If there’s a risk of a potential collision with an oncoming vehicle, the vehicle can alert the driver and apply the brakes. The Mach-E will be the first Ford product to offer phone-as-a-key technology, which allows owners to unlock and drive the vehicle simply by having their smartphone with them.

The Mach-E will be the first Ford to provide Active Drive Assist, permitting hands-free driving on more than 100,000 miles of divided highways in the U.S. and Canada – if the pilot continues to pay attention to the road ahead. Enabled by a new three-lens infrared camera, the system can track the driver’s head position and eye gaze, even while wearing most sunglasses. Ford claims it is the first major manufacturer to activate a driver-facing camera for this purpose, and the only one that’s infrared.

This feature will not be available at launch, but is available as a prep package that includes the camera and radar hardware with the option to purchase Active Drive Assist as an over-the-air (OTA) software update next year. The Mach-E will be the first Ford to provide this OTA update capability; nearly every computer module on the vehicle can be updated wirelessly. Owners can select a time (say, 3 a.m.) for updates while the Mach-E is parked, and most will be completed almost instantly after the vehicle starts. Longer updates also can be scheduled.

Ford has stated that it expects to deliver the first OTA software updates within six months after the vehicle goes on sale. Owners will receive notifications detailing the downloads, which can be applied using either Wi-Fi or cellular connections, depending on the update. Making its debut in the Mach-E – and also OTA-updateable – is the next-generation Sync infotainment system, which is launching with 4G LTE hardware. The Mach-E’s 15.5-inch screen and adaptive dash card interface will feature touch, swipe and pinch controls.

Charging infrastructure + cloud
As a full-range EV, recharging capability becomes a crucial aspect of the ownership experience. The mobile charger included with the vehicle can add an estimated 22 miles-per-charging-hour (m/ch) of range on a 240V outlet. Ford will offer a Connected Charging station to owners for home installation that can add an estimated 32 m/ch on a 240V outlet. The Mustang Mach-E will also permit DC fast charging, and with it, the extended-range battery is projected to add 61 miles (98 km) of range in approximately 10 minutes and enable a 10% to 80% charge in 45 minutes.

Amazon Home Services will begin installing the wall-mounted Connected Charging stations and 240-volt outlets for Mustang Mach-E customers in the U.S. later this year, which start at $800. Ford’s Team Edison is leveraging the FordPass ownership smartphone app and is working directly with Electrify America and other charging networks to help create a blanket of charging opportunities. Mach-E customers in the U.S. will receive 250 kWh of complimentary Electrify America charging through the app, the equivalent of three to five full DC fast charges.

Mach-E owners also will receive two years of complimentary access to the expanding pay-as-you-go FordPass Charging Network, which Ford claims is currently North America’s largest, with 13,500 charging stations and almost 40,000 individual plugs, and includes Electrify America’s network. “The goal for the Mach E was to provide a worry-free experience,” Hong said. “When you're on the go, you can put everything in your FordPass and your vehicle will tell you where is the next and most convenient place to charge based on your route.”

Thanks to the Mach-E’s connected OTA ability, maximizing range and efficient charging opportunities should only improve. An OTA-updateable Intelligent Range feature predicts remaining range based on past driving behavior, weather forecasts and crowdsourced data from other Mustang Mach-E vehicles. Future updates will increase this accuracy by factoring in real-time traffic and weather conditions, along with terrain profiles of a given route. The cloud-based feature will use Mach-E fleet averages to improve range estimates, even for a route never driven before.

According to Iorio, incorporating all this technology is part of vehicle development’s new paradigm. “The challenges here with the BEV are these integrated-software portions of the car,” he explained. “You're delivering on these new-school expectations that have to be flawless. I wouldn't say anything got easier with that, it got more exciting. But I’ll tell you what, when you're delivering another horse to the stable, it was a lot of fun.”

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