TESLA EVOLVES TO BATTERY SWAP

The 2015 Tesla Model S5 will be the first generation with complete battery swap as an option.

The 2015 Tesla Model S5 will be the first generation with complete battery swap as an option.


Tesla is finally offering battery swaps for the Model S — a feature that was first demonstrated in mid-2013, designed as a quicker alternative to charging. The concept is that a complete battery swap, which was promised to take as little as 90 seconds, would be far faster than charging even with an ultra-fast Supercharger, so you could be in and out of a station in roughly the same amount of time (if not less) than filling up with gas.

FOR NOW, THIS ISN’T A FULL DEPLOYMENT

This isn’t a full deployment, though: Tesla CEO Elon Musk teased the news earlier today in a tweet–as is often his practice–saying that the swap capability was “now operating in limited beta mode.”

The Harris Ranch TESLA Charging Station

The Harris Ranch TESLA Charging Station

Tesla will only be offering swaps at a special facility across the street from an existing Supercharger site in Harris Ranch, California (184 miles south of San Francisco and about 200 miles north of Los Angeles), in order to “to test technology and assess demand.”

It’ll only be available by appointment — you can’t just drive up and ask for a new battery — and the process now takes three minutes rather than the 90 seconds that had originally announced. The company says now that “for this specific iteration,” the swap process will take “approximately 3 minutes”–due to the need to remove the various shields and plates added last year to shield the battery pack from being punctured by road debris.

It will involve an unspecified number of Model S electric-car owners, who will be invited to take part in the test. Details and qualifications of which owners are eligible won’t be worked out for another week or so, Tesla told us.

Unlike the Supercharger station network, which allows Tesla owners to charge up for free, the battery-swap process will cost drivers “slightly less than a full tank of gasoline for a premium sedan,” Tesla says. “This technology allows Model S owners in need of a battery charge the choice of either fast or free.” We’d have to ballpark that number at $60 or higher, based on a 20-gallon tank and gasoline at $3 or more a gallon.

By contrast, use of Tesla’s Superchargers at any of the 1,784 existing Stations in its worldwide network is free. The test is “exploratory technology,” Tesla said, that presumably would help the company learn what potential exists for this or future battery swap initiatives.

The company says that it thinks it could get the process down to under one minute with “further automation” and changes to the cars, but it’s going to wait to find out just how much demand exists for the swaps before devoting engineering resources to it.

MAKING GOOD ON PROMISES

Tesla’s long-promised battery-swap technology, making charging up as quick as filling your gas tank, is finally here. Tesla CEO Elon Musk unveiled a demonstration of the Model S battery-swap capability at a flashy event held in Southern California in June 2013. You can view the official video via LuxuryPerspectives.com here.

The pitch then was that the company could swap a battery pack in less time than it would take to refill the gas tank of a comparable luxury sedan. In fact, the event suggested, two packs could be swapped in that time–with a 90-second swap time as was portrayed on stage.

The company feels it could cut that time to less than 1 minute with changes to the vehicle and further automation of the process.

The pilot program will help Tesla determine whether it should devote time and effort to making those upgrades, depending on the demand for battery swapping versus Supercharging. Given that hours-long charging times are one of the biggest criticisms levied against electric vehicles, we think it’s a given that Tesla hopes to build a network of battery-swap facilities that rivals the size of its 1,748 Supercharger stations worldwide.

The now-defunct "Better Place" battery swap facilities in Israel

The now-defunct “Better Place” battery swap facilities in Israel

The only other application of battery swapping for electric passenger cars thus far was the now-defunct Better Place project in Israel, which at its height had more than 20 swap stations in operation.

A TESLA LEGACY

Electric cars face daunting roadblocks on the entrance ramp to mainstream acceptance, including matching or beating a conventional car’s performance, stretching the driving range between recharging stops, cutting the time required for a recharge from several hours to a few minutes, and, most notably, lowering sticker shock to somewhere below electrocution.

While Mini Es, Mitsubishi i-MiEVs, Nissan Leafs, and Smart electrics have wrestled with these issues, they all bow down to the Tesla Model S, the thinking driver’s electric car. Consumer Reports called it the best car it has ever reviewed. We called it the car to buy when you’re buying electric.

These accolades for Tesla have piqued the interest of both investors and General Motors. To buttress its reputation as the breakthrough electric-car maker, Tesla is implementing two notable advancements: rapid recharging at company-owned Supercharger stations, and a means of exchanging a depleted battery pack for a full tank of electrons in 90 seconds (as promised in 2013).

More than 1,784 Supercharger stations are up and running worldwide. These hookups zap a Tesla S’s battery pack with 120 kilowatts of DC, 17 times the power available at 30-amp public charging stations and 13 times that provided by 40-amp AC home service. Tesla claims that plugging in at a Supercharger station for 20 minutes restores half the Model S’s charge. To sweeten the deal, the only cost is for the cup of coffee or lunch you enjoy while your car is juiced.

HOW IT WORKS

Battery swapping is Tesla’s second innovation.There is no grease monkey working under the car.

You park a Model S in a designated spot at a Supercharger station and the magic begins in the car’s shadow. The floor opens, computer-controlled tools unscrew the 39 fasteners that attach the 61-by-100-by-4-inch battery pack to the car, and a fixture lowers the 1300-pound box containing more than 7000 cells into a pit. A fully charged replacement battery is hoisted into place, and all power, cooling, and battery-diagnostic connections are restored. Automatic screwdrivers spin the fasteners to their factory torque spec, completing the swap in a minute and a half.

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The Model S was designed for rapid, automated battery changing with quick-release fluid and electrical connections. From the start, Elon Musk’s engineers were smart enough to realize that hours-long recharging is a joy killer for anyone hoping to use an electric car for long trips. Tesla’s battery-swap service uses the same assembly equipment in place at the Model S plant in Fremont, ­California. Supercharger stations went up and down the West Coast’s Interstate 5 and from Washington, D.C. to ­Boston.

The financial aspects are more complex than the mechanical details.

A Tesla S owner will pay $60 to $80 for a swap, plus the cost of shipping the battery back to a Tesla service center if going back to the same Supercharger station to re-swap is inconvenient. But the real return on ­Tesla’s investment of $500,000 per Supercharger station will come from the valuable (and saleable) zero-emissions credits Tesla earns in California. During the first half of this year, Tesla earned $137 million selling its ZEV credits, more than enough to fund the 237 Supercharger stations.

Exchanging batteries is not a new idea.

Electric delivery trucks used them more than a century ago, and they kept a fleet of buses rolling at the 2008 Summer Olympics in Beijing. But Tesla’s automated battery-swap scheme is the best hope today’s electrics have for achieving practically uninterrupted mobility.

But, it is a new idea for luxury automobiles, and with the announcement of a new line of mass-produced hydrogen-powered autos to hit the streets early in 2015, Tesla continues to make electric power a conveneint, attractive, and sleek attraction to consumers.