For electric vehicles, 'fast charging' standard is slow going

Electric vehicles lack a "fast-charging" plug standard for rapid replenishment of spent batteries. Should consumers with EVs on their mind be worried?

It's infuriating to take electronic devices overseas, isn't it?

Different voltages aside, it seems beyond reason that the dawn of the 21st century has come and gone and yet we still have 12 -- count 'em, 12! -- AC power plug shapes in operation.

Need to charge your laptop? Better find the right plug. (Square? Round? Two-prong? Three?)

(And don't even get me started on the various proprietary plugs for mobile phones, although manufacturers say they're working on a universal solution.)

I wrote on SmartPlanet back in 2009 that a plug standard was among the most pressing issues for widespread adoption of electric cars. So call it worrisome, then, when the New York Times reveals that we're still miles away from a single connector -- particularly when it comes to "fast charging" in public places.

First, the playing field:

  • SAE J1772 Level 1, the standard 120-volt cable developed by 150 automakers, manufacturers and utility companies that is the default (read: slow-charging) option for a new EV. A Nissan Leaf would take almost 20 hours to recharge.
  • SAE J1772 Level 2, a 240-volt cable intended for public spaces. A Nissan Leaf would take almost eight hours to recharge.
  • Chademo, a 480-volt DC fast-charge standard developed in Japan by Nissan, Mitsubishi, Subaru and Tokyo Electric Power. It uses a connector that's different from a standard plug, so two separate sockets are required. A Nissan Leaf would take 30 minutes to replenish 80 percent of its battery capacity.

Currently, engineers are working to bring the SAE J1772 standard to DC fast-charge circuitry and unify all three charging methods in a single connector.

Automakers are interested in a single standard -- it's cheaper for them, obviously, to support only one -- but Chademo-supporting Nissan Leafs and public chargers are already in the wild, since the new J1772 standard isn't yet ready for primetime. (It's expected in 2012.)

But with such drastically different charging times, plug preference is also a matter of competition in the marketplace.

Csaba Csere writes:

Overcoming the limitation of a short driving range is vital to achieving acceptance by consumers who want uncompromised, do-everything vehicles. The potential solutions all have drawbacks. Larger batteries are expensive and saddle the car with added weight. An onboard generator turned by a gasoline engine, as used in the Volt plug-in hybrid and similar future models, are another possible solution, but such systems add cost and pounds — and compromise the emissions-free image that attracts consumers to electric cars in the first place.

A Chademo charger could theoretically be reconfigured to support J1772, according to a source in Csere's article. But it's got me thinking: will consumers resist purchasing an EV with a proprietary charging format that could soon be obsolete? (Or is that too far off for their concern?)

And moreover: will the increasingly electrified auto industry be able to manage the rapid pace of iteration in the electronics industry when product life-cycles are measured in years, not months? In-dash telematics is one thing, a vehicle's powertrain is another. Are these just growing pains for a new industry, or a new challenge to future-proof against as we seek faster ways to charge our vehicles?

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