Creating the RAV4 EV
What do you do when the CEO of your company says that he wants an electric vehicle sooner rather than later? You make sure that you get it done—fast. And the team at Toyota, along with their partners at Tesla Motors, did just that.
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So consider this for a product development challenge. On May 20, 2010, Akio Toyoda, president and CEO of Toyota Motor Corp., and Elon Musk, chairman, product architect and CEO of Tesla Motors, announce that the two companies have entered into a collaborative partnership. Akio Toyoda wants to come out with an electric vehicle. He wants it to come out sooner rather than later. In the meantime, the people at Tesla are developing their Model S roadster. They are keen on getting their own product (not a Tesla powertrain in a Lotus Elise, as had been their original car) on the road, sooner rather than later.
The task for the development of the Toyota vehicle was assigned to the Toyota Technical Center (TTC), USA, in Ann Arbor, Michigan. And Gregory D. Bernas, TTC chief engineer in the product development office, to whom responsibility for what was to become the 2012 RAV4 EV, recalls that this was a program with an exceedingly tight time line.
On June 4, Toyota and Tesla engineers got together for a meeting during which time they worked out who would be doing what. There was a bit of an issue, Bernas says: Each group thought the other guys would lead the development. As it turned out, not surprisingly, perhaps, given that the number of decades Toyota has been developing vehicles is greater than the number of years Tesla has, that the lead on the program went to Toyota and the powertrain to Tesla.
Meanwhile, Akio Toyoda was anxious that the program proceed rapidly. So Bernas and his team had to work fast. They provided Tesla with a couple of RAV4s with conventional engines and had them converted to electric vehicles. They had these cars within a month.
Bernas says that they made a commit-ment to have driveable vehicles within six months of the start of the program. They had 31 vehicles built, which Akio Toyoda had the opportunity to assess in real-world driving conditions. Yes, Bernas says, they used Tesla roadster components for these 31 SUVs. “But it allowed us to show how the technology works and demonstrate the performance of the vehicles.”
According to Sheldon Brown, executive program manager at TTC, they instituted a program called “E-FaST,” which stands for “Early Field and Suitability Testing.” This was a real-world test of the vehicles-in-development, putting them on the roads in Los Angeles and San Francisco, subjecting them to a variety of conditions, including highway driving, congested traffic, hill climbing, hot temperatures, and the like. Brown acknowledges, “We recognized that for this technology to be successful in the market, we had to execute it just right.” He says that they wanted to develop, “Technology that people could trust.”
So what they had to do was develop a vehicle that was as bullet-proof as a Toyota yet with technology that is more characteristic of Silicon Valley than the traditional auto capitals.
In May 2012, 24 months after the announcement, Toyota revealed the production RAV4 EV at the Electric Vehicle Symposium 26 in Los Angeles. And by the end of July they put journalists behind the wheels of the SUVs.
Asked if he thinks this truncated timeframe might become the “new normal” for product development, Bernas reflects of the program, “It was so different. Just to do a normal program in 24 months is very challenging. This . . .” and he pauses. Bernas continues, “The nitty-gritty of the development took 16 to 18 months.” Realize that the folks at Tesla wanted to protect their intellectual property as regards the battery system and motors and the people at Toyota didn’t want to give away the specifications and the procedures that make Toyotas Toyotas.
“It was difficult and challenging to say the least,” Bernas admits.
But perhaps predicated on the successful development of the capable, competent and credible SUV in this short period of time, he says, “I think this could be the new normal for low volumes, for taking an existing platform and converting it to a different type. I don’t think it is the norm for high-volume vehicles.”
And it needs to be noted that this SUV is a decidedly low-volume vehicle. According to Bill Fay, Toyota division group vice president and general manager, they’ll be producing 2,600 RAV4 EVs at the Toyota Motor Manufacturing Canada plant (where the internal combustion engine versions are produced; the electric powertrain for the EVs will be produced by Tesla in Fremont, CA, and shipped to the plant for installation). These vehicles, which have a monospec, have an MSRP of $49,800. They will be made available during a three-model-year period of time in select dealerships in California. Period. He suggests that they may expand the availability to other markets, like New York City and Boston, but the commitment is to that state and that number in that timeframe, fundamentally to meet California mandates requiring a number of zero-emission vehicles (ZEVs) sold during 2012-2014 predicated on an OEM’s overall sales in that state. (The Prius Plug-in and a Scion iQ electric urban car-sharing program will also help meet the requirements.)
According to Sheldon Brown, the fundamental structure and the motor used for the RAV4 EV and the Model S is essentially the same, but he notes that in the Tesla application it is oriented for rear-wheel drive and for the Toyota front. The DC-DC converter is approximately 98% the same. The charger is identical. The battery is vehicle-specific: the liquid-cooled battery pack for the RAV4 EV, which is rated at 41.8 kWh, consists of some 4,500 cells. The battery is capable of providing “at least” 129 kW of instant power during 30 seconds of wide-open throttle acceleration, though the nominal motor output is 115 kW. The charge time for the battery, using a 240-v AC/40-amp charger (Toyota is working with Leviton (leviton.com.) for providing home charging stations for the vehicle), is five to six hours. (There is a 120-v, level 1, 12-amp charging cable provided with the vehicle for use when 240-v charging is not available; this is when there is a whole lot of time available, because it takes approximately 44 hours for a recharge.)
One of the things that they worked on was creating a vehicle that on the one hand had good range and on the other hand could provide “spirited” driving. So they developed a system that has both Normal and Sport modes, with the latter providing a more aggressive accelerator feel as well as boosting the maximum speed from 85 mph to 100 mph.
And they also have the charging setup in two modes: Standard and Extended. In Standard, the battery charges to 35 kWh. This provides enough power to drive an EPA-estimated range of 92 miles. The Extended range allows the battery to change to its full capacity of 41.8 kWh, which means an estimated range of 113 miles. Why the two modes? Because the Standard mode helps maximize battery life.
The RAV4 EV, Brown says, uses the RAV4 V6 as its baseline. While the powertrain, obviously, is wholly different, there are a number of other modifications that had to be made under the hood (e.g., a new radiator and condenser), on the chassis (e.g., new brakes), on the exterior (e.g., LED lights all around), and inside the cabin (Thinsulate acoustic treatments under the headliner and trim).
This is not the first time Toyota has put a RAV4 EV on the market. There was an earlier version that was produced between 1997 and 2003, again to meet California mandates. And, again, this was a limited-production vehicle (though built in Japan): 1,484, of which, according to Bill Fay, some 450 are still on the road.
One can only image that in some 10 years’ time there will be a whole lot more EVs thanks to developments like the 2012 RAV4 EV.
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