Last year, Plug In America's Expert Assistance and Research Group launched its first-ever consumer-oriented evaluation of plug in battery performance. It was intended to educate consumers on battery reliability and extended warranty purchase options, along with supporting industry-wide adoption of standard battery performance warranties.
Last year's survey found that many Leaf owners were experiencing a high degree of stability and reliability. Along with that, the study clarified that ambient temperature seems to be the most significant factor in battery deterioration. Soon after release of the findings, Nissan announced a new battery warranty for Leaf owners. Nissan executive vice president Andy Palmer encouraged Leaf owners to read the Plug In America survey results.
More people own Leaf than Roadsters, but the Roadsters have been on the road longer. The expensive Roadster electric sports car (which started at $109,000) was launched nearly three years before the Leaf, in 2008. About 2,500 Roadsters were sold through 2011, and Roadster owners have had a lot of experience behind the wheel. While the Leaf and Chevrolet Volt were lauded for returning EVs to the market following the limited number built by major automakers in the 1990s, the Tesla Roadster actually opened the door for EV commercial production.
Roadster owners are encouraged to visit the Plug In America website and take the survey. Like the Leaf survey, most of the questions focus on the battery pack's performance and the influence of determining factors – time and mileage in use; how it compares to owner expectations; how well the Roadster's active thermal management protected the battery pack in hot and cold weather; and distinctions between those who've experienced the different versions of the Roadster – 1.5, 2.0 and 2.5 and the mainstay Roadster compared to the Roadster Sport. There's also a question dealing with what owners might expect when considering purchasing an extended warranty.
The survey project is led by Plug In America's Chief Science Officer Tom Saxton. Along with this sort of real-world battery performance research, Saxton and the PIA research group conducted their first ever performance evaluation of charging station down time last year.
Like owners of conventional gas cars, owners of electric cars are naturally interested in understanding expectations of long-term performance and maintenance issues.
In the fall of 2012, Plug In America conducted a survey of Nissan LEAF owners to gain a better understanding of the unexpected battery capacity loss reported by some LEAF owners in hot climates such as Tucson, Arizona. In December, results from the survey were released.
Around the same time, Nissan executive vice president Andy Palmer announced an enhanced limited battery warranty for the LEAF which covers battery capacity performance for 5 years or 60,000 miles, the first such warranty for an all-electric vehicle from a mainstream automaker. In the warranty announcement, Palmer encouraged all LEAF owners to read Plug In America's LEAF survey report, a strong validation and recognition of Plug In America's effort. The LEAF survey is ongoing.
This week, Plug In America launched a similar survey of Tesla Roadster owners. Although absent reports of issues with battery capacity loss, the Tesla Roadster user base has significant experience with electric vehicles that have been on the road since as far back as 2008. With the Roadster survey, Plug In America plans to explore several topics:
How does the Roadster battery pack hold up over time and miles?
How does this compare to owner expectations as set by Tesla Motors?
How well does the Roadster's active thermal management protect the battery pack against hot and cold weather?
How do version 1.5, 2.0 and 2.5 Roadsters compare in battery longevity and major maintenance?
Is there a difference in drivetrain maintenance between the Roadster and Roadster Sport?
How common are major Roadster drivetrain component replacements?
What should owners know when considering purchasing an extended warranty?
Owners of the Nissan LEAF or Tesla Roadster are invited to participate in these surveys:
Nissan LEAF Battery Survey
Tesla Roadster Battery Survey
Please feel free to share these links with other LEAF and Tesla owners or send them a note from our Tell-a-Friend page.
Plug In America values the privacy of survey participants and will not use participants' names or email for any purpose other than matters related to the survey.
Results from the Roadster survey, and possible updates to the LEAF survey, will be made available as these studies progress. Plug In America expects these studies will be followed by others as staff and resources permit.
Current and potential plug-in vehicle owners interested in objective third-party research of issues important to EV drivers are encouraged to donate generously to Plug In America in support of this vital work.
Chief Science Officer
Plug In America
The LEAF and Roadster survey efforts are being lead by Plug In America's Chief Science Officer, Tom Saxton. Saxton and his wife have been driving electric since 2008 when they purchased a used 2002 Toyota RAV4-EV. Their all-electric garage also includes a 2008 Tesla Roadster and a 2011 Nissan LEAF. Together they have driven over 65,000 all-electric miles. Saxton's previous work includes the Plug In America Electric Vehicle Infrastructure Study, released at EVS-26 in May, 2012, and an informal survey of Roadster owners in the Pacific Northwest on battery capacity performance in 2011.