The electric Toyota RAV4 is perhaps the unlikely result of a meeting of the minds between two CEOs, Toyota’s Akio Toyoda and Tesla’s Elon Musk. Everything about the program is unusual, in that it’s a collaboration between one of the world’s auto giants and a start-up EV maker. And it’s also something beyond business as usual when Toyota lets auto writers like me get behind the wheel of what remains very much a work in progress.

This new plug-in car is a descendant of the electric RAV4 that briefly ruled in California during the late 1990s and early 2000s (actors Tom Hanks and Ed Begley, Jr. still have them). Driving on the roads around San Diego, I was struck by how much it maintained its Tesla family resemblance — not surprising, considering how many components (from batteries to the motor) are shared with the Roadster. It sounds and accelerates like a Tesla, although it’s certainly not as fast — the zero to 60 dash takes an estimated nine seconds. 

I was having a grand old time driving the RAV4, even getting tire squeal as I dive bombed the racy electric vehicle around streets lined with healthy looking joggers. Tesla, which did much of the engineering on the car, dialed in a lot of regenerative braking, which asserts itself every time I lifted my right foot. I'm used to that from BMW's Mini E, though maybe there should be a way to turn it down. But then I noticed something odd: The Toyota/Tesla prototype, so apparently intent on showing me a good time, started, well, slowing down.

It was as if the car went on strike: One minute we were bombing along and the next the RAV4 had decided to crawl off the line like an arthritic pensioner. It repeated this behavior several times, but was fine as soon as it got some momentum up. Toyota’s Scott Haddad was along for the ride, and he was uncertain what was causing the issue, though he thought it might be an overheated battery.

We’re finding out that batteries have some sensitivities. They don’t much like cold, and both the Nissan Leaf and Chevrolet Volt lose range when temperatures dip below freezing. But heat is an issue, too, and Tesla is one of the more advanced automakers in designing systems that allow battery packs to keep their cool. What I might have been experiencing is the battery management intervening (after I exhibited some hot-dog driving) to keep the pack’s temperature within range.

But Sheldon Brown, executive program manager for the Toyota Technical Center, told me later that the problem could be somewhere in the electronics. He did say his engineers were able to replicate the strange slowdown.

Brown said the actual production car will have sophisticated liquid-cooled battery management that is unlikely to behave as it did in the test vehicle, one of 35 to be built from a V-6 donor car (and later to be crushed, alas).

The electric RAV4 was announced in the summer of 2010, and will hit the road in 2012, says Toyota’s Jana Hartline. She offered some useful information, including that the car (again, as a prototype) weighs nearly 4,000 pounds, and (because the lithium-ion battery is stored underneath) offers 73 cubic feet of storage — a lot for an electric vehicle. There won’t be a price until next year.

Another challenge in the prototypes is very long charge times: 28 hours at 110 house current, and 12 hours on a 220-volt battery charger. This will be significantly improved before the production cars appear, Hartline said. The tradeoff with a relatively large 37-kilowatt-hour pack is longer range, reportedly from 90 to 120 miles. Any EV Tesla touches appears to be destined to be a long-distance traveler.

The battery RAV4 gets a fresh front end redesign from Toyota’s CALTY studio in Newport Beach, and some interior tweaks, including restyled seats, a pushbutton drive-by-wire transmission and a new instrument panel (not on the test cars).

Haddad said it’s conceivable that the electric RAV4 will be built at the cavernous former GM/Toyota NUMMI plant in Fremont, Calif., recently acquired by Tesla. That would be a good use of the plant, which certainly has plenty of space to accommodate both the RAV4 and Tesla’s Model S.

All in all, I liked the electric RAV4 and think its practicality should net it some fans, especially if weight is reduced, Toyota doesn’t price it too high, and charging times are brought within reason. It’s not going to be a high volume car — a few thousand annually, but I wouldn’t expect them to hang around the lot. If I find out what caused my car to slow down, I’ll let you know.

Jim Motavalli ( @jmotavalli ) writes about cars, technology and the environmental world to anyone curious enough to ask.

A rip-roaring first ride in the electric Toyota RAV4 built with Tesla
I liked this small battery SUV fine, though it exhibited a mysterious slowdown. If charge times are speeded up and the price kept within reason, it should sell.