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DC fast charging not as damaging to EV batteries as expected

As convenient as DC fast charging is, there have been lots of warnings that repeated dumping of so many electrons into an electric vehicle's battery pack in such a short time would reduce the battery's life. While everyone agrees that DC fast charging does have some effect on battery life, it may not be as bad as previously expected. Over on SimanaitisSays, Dennis Simanaitis, writes about a recent presentation by Matt Shirk of the Idaho National Laboratory (INL) called DC Fast, Wireless, And Conductive Charging Evaluation Projects (PDF) that describes an ongoing test of four 2012 Nissan Leaf EVs that are being charged in two pairs of two. One pair only recharges from 50-kW DC fast chargers, which the other two sip from 3.3-kW Level 2 chargers exclusively. Otherwise, the cars are operated pretty much the same: climate is automatically set to 72 degrees, are driven on public roads around Phoenix, AZ and have the same set of dedicated drivers is rotated through the four cars. "Degradation depends more on the miles traveled than on the nature of recharging." What's most interesting are the charts on page seven of Shirk's presentation (click the image above to enlarge), which show the energy capacity of each of the four vehicles. When they were new, the four batteries were each tested to measure their energy capacity and given a 0 capacity loss baseline. They were then tested at 10,000, 20,000, 30,000 and 40,000 miles, and at each point, the DC-only EVs had roughly the same amount of battery loss as the Level 2 test subjects. The DC cars did lose a bit more at each test, but only around a 25-percent overall loss after 40k, compared to 23 percent for the Level 2 cars. Simanaitis' takeaway is that, "INL data suggest that the amount of degradation depends more on the miles traveled than on the nature of recharging." The tests are part of the INLs' Advanced Vehicle Testing Activity work and a final report is forthcoming. These initial numbers from IPL do mesh with other research into DC fast charging, though. Mitsubishi said daily fast charging wouldn't really hurt the battery in the i-MiEV and MIT tests of a Fisker Karma battery showed just 10-percent loss over 1,500 rapid charge-discharge cycles.

Nissan shows off Le Mans Prototype, says it's world's fastest electric racer [w/video]

Nissan has announced plans and details around its upcoming all-electric racing car, the ZEOD RC. The Zero Emission On Demand Racing car is said to be capable of a top speed in excess of 300 kilometers per hour (186.4 miles per hour), is shaped a bit like the closed-cockpit version of the DeltaWing (albeit, to our eyes, better looking) and will make its debut in 2014 at the 24 Hours of Le Mans. This weekend, visitors to the race will have the opportunity to view the prototype near the Circuit de la Sarthe.
Nissan's ZEOD RC has been invited by Le Mans organizers to compete as the Garage 56 entry in next year's race; that's essentially a spot on the grid held for vehicles with new and/or cutting edge technology.
Short of announcing a partnership with Michelin to develop tires for the EV racecar, however, Nissan is mum on any kind of battery or motor specification for the ZEOD. The press release (below) offers a sense that the Nissan and Nismo teams have still got a lot of work to do before the 2014 race. Ben Bowlby, designer of the ZEOD RC, says "We have many options to consider and test. The test program is part of a longer term goal of developing a system and a set of rules for this type of technology in partnership with the ACO that would be best suited to competing at the highest level of this sport."

Nissan Leaf has 2nd-best sales month ever, Chevy Volt does a 2013 repeat [UPDATE]

UPDATE: The official press release says that "Volt [sales were] up 7 percent," but Randy Fox let AutoblogGreen know that this is simply due to a change in the fleet/retail mix between March 2013 and 2014. The actual number sold was exactly the same in the two months. A month ago, Nissan's director of EV sales and marketing, Toby Perry, said he expected to see the Leaf's sales momentum continue into March. It wasn't a big leap, since January and February were slow sales months in 2013 (around 640 each) before a big climb to 2,200 in March. In 2014, the first two months of the year were better (around 1,300 each) but Nissan can still be happy that the Leaf just had the best March ever and its second-highest sales month ever, with 2,507 sold. That's a 12.1 percent increase from 2013 and Perry said in a statement to AutoblogGreen that one reason is all of the buyers who are becoming evangelists for the vehicle. "We've also seen an increase in showroom traffic as we enhanced our marketing presence in March," he said. Nissan pointed to cities like Washington, DC, Raleigh-Durham, NC and urban areas in Texas as strong Leaf markets last month. On the Chevy Volt front, January and February were also slow months in 2014, down roughly half from the 2,000-ish the plug-in hybrid was selling at the end of 2013. For 2014, sales were up slightly from the first two months of the year and Chevy spokesman Randy Fox told AutoblogGreen that the March number was "pretty flat, year-over-year." Even with that warning, we were surprised to see the total come in at 1,478. Why's that? Because the total for March 2013 was ... 1,478. So, yeah, that's pretty steady even if there were 26 selling days in March period this year compared to 27 last year. As always, our more complete report of last month's green car sales will be coming soon. News Source: General Motors, Nissan Green Chevrolet GM Nissan Electric Hybrid PHEV ev sales