When Carol Straubel's 14-year-old son was re-building an old
electric golf cart in 1989, she found herself driving the boy from town to town
sometimes as far as 50 miles, in search of batteries, tires and electric motors.
"He was passionate about it,"
Straubel recalls. "He wrote to the manufacturers for information. He worked on
it every day, all day long, all evening long, until he got it to run."
What Straubel didn't know back then
was that her son, "JB" Straubel, would still be on a motor-and-battery mission 20
years later. JB Straubel, now the chief technical officer of Tesla Motors Inc., is the winner of the
News Engineer of the Year award, largely because he's as obsessed with
electric vehicles today as he was when he and his mother were crisscrossing Wisconsin
in search of golf cart parts in 1989.
The difference, though, is that the
2009 version of JB Straubel is now applying that same fire and passion to a
mission that's meaningful not just to him, but also to the global auto industry
and to the nation, as well.
"It really feels like we're trying
to change the world," says JB Straubel (JB stands for Jeffrey Brian; he prefers
not to punctuate it) of his company's task. "There's a real David and Goliath
feel to it."
If the task of changing the world is
daunting, however, that hasn't stopped Straubel and his fellow engineers at
Tesla. Before rolling out the prototype Tesla Roadster in 2006, the company's
engineering staff set their sites on an incredibly ambitious 250-mile battery-only
range for the vehicle, and then came within a hair of meeting it. The Roadster's
final, EPA-verfied, 244-mile range was approximately three times that of the
now infamous General
Motors EV1, which hit the streets a decade earlier.
stunning achievement not only turned heads among such competitors as General
Motors, it set the stage for the emergence of electric vehicles in a way that
hadn't been expected yet by the automotive community. At the time, most
engineers wondered aloud about the range and costs of electric vehicles (EVs),
especially since no production cars had yet reached 150 miles, let alone 244.
have been substantially easier to make a car that was quick, handled well, and
did everything else the Roadster does, but had 150 miles of range," Straubel
says now. "But holding the bar at the 200-mile level was something that was
critical to changing perceptions about EVs. From the earliest days, it was
something we set out to do."
A Bigger Vision
For Straubel, however, taking aim at daunting EV goals now looks
more like a matter of destiny than determination. Since finding the rusty,
30-year-old golf cart in an Egg Harbor, Wisconsin, junkyard 20 years ago,
Straubel appears to have been on a trajectory that would inevitably land him in
world of vehicle engineering. While still in junior high school, he built a
working hover craft for a science fair. Another time, he commandeered his
family leaf blower to construct a blow furnace, which he used to melt aluminum,
although it was never clear why a pre-high-school-age boy needed molten
born to be an engineer," Carol Straubel recalls. "He was always passionate
about anything that had wheels and required engineering."
surprisingly, Straubel's college days also neatly positioned him for the world
of alternate propulsion. At Stanford
University's School of Engineering he created his own academic major in
energy systems engineering and earned a master's degree in it.
"It was a
great fit for me because it let me follow my passion," Straubel says now. "It's
kind of eerie to see how my career has followed what I wanted to do at the
joined Tesla at the ground-floor level in 2004 after stints at Rosen
Motors, which built hybrid powertrains for cars, and after attempting to
start his own company aimed at creating electric airplanes. Before arriving at
Tesla, he also worked with Stanford colleagues on a solar vehicle racing team
and kept in touch with friends at AC Propulsion,
which built an electric sports car capable of going from 0 to 60 mph in under
four seconds. No matter what Straubel did, electric propulsion was always at
"I was talking to anyone and
everyone to promote the idea that EVs had turned a corner," Straubel recalls.
"I told them that with new battery technology, they could go much, much farther
than anyone thought was possible. I wanted to demonstrate my ideas in a working
vehicle and break a few perceptions."
aerospace connections, Straubel eventually met PayPal entrepreneur Elon Musk and described his
ideas. Musk subsequently invested in Tesla Motors (which was looking for an
initial round of funding) and brought the 29-year-old Straubel on board as
chief technology officer.
"Elon had a
much bigger vision for (the company)," Straubel says. "It aligned so well with
what I was already doing that it was impossible not to get excited."
For Tesla Motors, however, the transition from a loose group
of Silicon Valley rebels to automobile
manufacturer was not an easy one. Suddenly, the company's engineers had to
worry about issues such as manufacturability, reliability, safety and cost. The
idea of building a high-end, high-performance, electrically-powered two-seat
vehicle now looked more daunting, especially since the new engineering team had
almost no experience in the auto industry.
beginning, however, Straubel had no intention of backing off his primary goal,
which was to build a car with enough range to change those public
a 250-mile range," Straubel recalls. "That was the number we were gunning for
from Day One."
Straubel, the engineering team began by picking a small form-factor lithium-ion
battery cell, like those used in consumer electronics. In all, Tesla engineers
employed more than 6,800 of the cells, which measure 18 mm in diameter by 65 mm
long (slightly larger than a AA battery), in a pack that weighs about 450 kg
(990 lbs). By combining thousands of small cells, rather a few huge ones, the
engineering team was able to maximize heat removal because the smaller cells
offered vastly more surface area, they say. In a
white paper on the subject, Tesla's engineering team explains that the
surface area of the 6,800 batteries is 27 square meters - about seven times
more than if they had used 20 large batteries. That means they have about seven
times more area for heat transfer at the surface of the cells.
Straubel and other Tesla engineers teamed up to create a patented cooling system
that mitigates the possibility of thermal runaway - a phenomenon that has been
known to happen, however rarely, in laptops and other consumer electronic
products that use lithium-ion. Tesla's cooling system uses a manifold and
cooling tubes to run a 50/50 mix of water and glycol through the pack, drawing
heat away from the batteries. As a result, the possibility of a cell sparking
and setting a neighbor afire is dramatically diminished.
energy density of these cells increases, the number of packaging and cooling
problems increases," Straubel says. "You're trying to package a lot more energy
into a much tighter space and suddenly cooling becomes a big issue."
Pulling The Right Levers
Despite the engineers' best efforts on the battery, however,
Straubel and his team quickly found that they were still falling far short of
their 250-mile goal. Even with a battery pack energy density approaching 200
W-hr/kg, Straubel says, the vehicle initially achieved a range of about 170
miles. Worse, there was no obvious culprit to blame for the shortfall.
of those classic problems where there's not a single major solution," he says.
"It really takes a broad systems-level viewpoint to understand all the little
‘levers' you have, and to understand that you can pull 10 or 15 small levers to
get a good outcome in the end."
Tesla's team pulled a multitude of those "levers" to reach their goal. Primary
among those was improving the vehicle's aerodynamics, decreasing its rolling
resistance, changing the brake calipers, adjusting tire pressure and switching
from a two-speed to a single-speed gearbox.
Straubel, the stickiest of those problems was the gearbox. Early on, the
engineering team had envisioned the high-performance vehicle as a two-speed,
despite the fact that an EV's torque curve enables it to work in a single-speed
configuration. Over time, the engineering team ran into difficulties, the
biggest one being that the vehicle was far less efficient than they had
expected. Engineers argued whether the extra gears, clutches and weight were
really a benefit to the vehicle.
around a table and said, ‘Look, we'd be better off with a single speed vehicle
where we put more focus on increased torque and power out of the motor, rather
than relying on this old-world solution of complicated gearboxes and moving
mechanical parts,'" Straubel recalls. "In hindsight, it was absolutely the
right thing to do."
The engineering team also squeezed out
a tiny bit more range by employing a so-called a "roll-back seal caliper" in
the brakes. The device, which pulls the caliper away from the disc when the
brakes are released, eliminates residual drag forces between the caliper and
disc when the brakes aren't being actuated.
Straubel says that the caliper and
other small fixes enabled Tesla to boost its range toward to the 250 range. EPA
tests on a dynamometer by a third-party vendor verified that the Roadster
achieved a total range of 244 miles.
"At some level, you're always
hoping to do better," Straubel says of the fact that their effort fell short of
250. "But we were happy to get to 244."
Man On A Mission
Colleagues say that Tesla couldn't have done it without Straubel's
quiet leadership. Straubel stayed the course on their goal of 250 miles and was
flexible when the team needed him to be, they say.
strategy doesn't appear to be working, JB is able to stop on a dime and change
the company direction," notes Kurt Kelty, director of energy storage systems
for Tesla. "Not only is he able to change his own direction, he's able to rally
everyone around him to support the new direction."
important of all, Straubel's dedication to the EV cause seems to be the result
of a strongly held set of beliefs. Kelty says he has witnessed Straubel's sense
of cause, even outside the confines of Tesla. "I've caught him on business
trips changing light bulbs in hotels to CFLs (compact fluorescent lamps)," he
says. "He has even bought a box of light bulbs and provided the box to the
hotel manager and shown him how easy it is to make the change."
"JB is at Tesla because he believes
it's the best place to put his efforts in order to make electric vehicles
happen," adds Drew Baglino, senior electrical engineer at Tesla. "He really
does think that this is where he can make the most impact on a problem that the
and the industrialized world has."
Straubel's efforts to change
perception of EVs are evidently working. After Tesla earned some measure of public
success with its stellar EPA rating, former GM executive Bob Lutz admitted to
changing his mind about electrics. "They have a real shot at success," Lutz
told Newsweek magazine in
December, 2007. "Their Roadster, if and when fully reliable, is an
extremely attractive proposition."
To be sure, the road hasn't always
been smooth for Tesla, and multiple stumbling blocks still lie in its path. In November, 2008, Newsweek
pointed out that Tesla was traversing a rocky road after its first 40 Roadsters
went out of the factory with drivetrains that needed to be replaced. The
company has also been beset by messy firings and legal entanglements, and a few
reviewers have complained that the vehicle isn't reaching its 244-mile range (A
Wall Street Journal review said the vehicle achieved ranges of
approximately 144 and 168 miles). Moreover, price tags for early Roadsters have
passed the $100,000 mark, making it a more logical choice for wealthy
celebrities like George Clooney and Matt Damon than for middle-class Americans.
Still, reviewers have been
generally positive. Car
and Driver, Edmunds.com, and
Magazine, among others, have been enamored with the vehicle, especially
its 3.9-second 0-to-60 mph acceleration. It has "smooth with amazing
acceleration, comfortable seats, and plenty of head and leg room," notes Design
News reader Stuart Koford of Cincinnati,
OH, who owns a Roadster. "No
problems so far."
Straubel, however, won't be
satisfied until he can change more of those public perceptions about EVs.
Recently, Tesla announced that it will produce a seven-seat sedan called the
Model S, which will offer a variety of ranges up to 300 miles, starting at
$49,900 in 2011. By going to larger production volumes, Straubel believes he
can drive the battery price down to $300/kW-hr, ultimately placing pack cost "in
the ballpark" of $18,000. That, he says, would help cut the overall cost of the
car. For now, however, Straubel plans keep pushing the mileage envelope.
Challenges like those are what keep him going, say those who know him best.
"To find a place to do what he
loves is amazing," notes Carol Straubel. "And to have it matter to so many is
that much better."
Read about the runners up for Design News' 2009 Engineer of the Year!