a laptop on a power-saving regime. REVive will be a standard feature in future ... charge] won't buy or lease battery EVs,â says Moos. âThose who [do] will learn.
enough to limp home: The Daimler Smart ForTwo electric car lets you get below the red line. photoS: Daimler
NXR subcompact to be released later this year in India and Europe. The car comes with an already substantial 160-km range, double that of the carmaker’s EVs powered by traditional lead-acid batteries. Reva’s solution has merit, according to Andrew Burke, a research engineer and battery expert at the Institute of Transportation Systems, at the University of California, Davis. He says that although deep discharges are in An Indian EV manufacturer may just have the cure general bad for battery life, they can be for range anxiety allowed once in a while without causing real damage, given that the extra range “This is really a very complex ank cards let you overdraw is profoundly reassuring to customers. problem,” says Chetan Maini, Reva’s your account when you must on Burke was himself reassured a decade ago, when he drove an electric the understanding that you’ll chief technology officer. “This is not pay it back when you can. If you could something that you could fix in an car that Honda marketed briefly under California’s zero-emissions vehicle do the same for your electric car by algorithm that meets all situations.” overdrawing the battery, it’d sure When REVive receives a text or voice program. On three or four occasions alleviate range anxiety—the fear that message from the driver, it remotely he miscalculated how far he’d be accesses the vehicle’s three-year store driving but nevertheless made it home, you might get stranded far from an electric plug. of data on such crucial parameters as thanks to the car’s limp mode. Inching Overdrawing your battery simply the battery’s age, the number of charge along was no fun, recalls Burke, but means taking advantage of a power “I was happy to get home any way.” reserve that today’s control systems Limp mode is a feature on the deliberately build in to preserve the updated electric-drive version of the electrodes and thus extend battery Smart ForTwo, which Daimler began life. The reserve can amount to test-leasing in December, according to 30 percent of the battery’s capacity. In Pitt Moos, the vehicle’s product manager. the Chevrolet Volt, a plug-in hybrid But Moos sees no need to proceed that will use a gasoline engine as a further to the “hassle” of a system such range extender—and thus can afford as REVive, betting instead that time and to protect the battery’s life very consumer experience will dispel range doubly green: The Reva carefully—the pure-electric reserve anxiety. “People who are very scared of NXR runs on volts alone. photo: Reva Electric Car Co. will reportedly come to 40 percent. getting stopped by zero percent [state of Reva Electric Car Co., based in charge] won’t buy or lease battery EVs,” Bangalore, India, and the world’s cycles, whether it’s been scorching in says Moos. “Those who [do] will learn leader in electric vehicle (EV) sales, is Mumbai or freeze-thawing in Oslo, and the cars and feel perfectly safe after a how aggressively the car has been driven. while. They will pass their experience parlaying data from the 135 million REVive feeds that data to algorithms, kilometers (84 million miles) logged along, and the market will grow.” Still, if REVive can assuage range by its EVs into an expert system that resets the range gauge, and puts the anxiety, it will boost the sales of the Reva, can give drivers an extra 10 km. The car in a “limp mode” akin to that of system, called REVive, uses remote a laptop on a power-saving regime. push other manufacturers into similar REVive will be a standard feature communications to enable the system battery-management schemes, and in future Reva EVs, starting with to determine how much extra charge expand the EV market that much faster. a lithium-ion-battery version of its can be accessed without doing harm. —Peter Fairley
Good to the Last Volt
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