Nissan Leaf tops EV safety ratings
BY TERRY MARTIN | 26th May 2011
The Leaf was one of six vehicles to be tested – and to achieve a five-star rating – in the latest round of Euro NCAP testing, which included the Lexus CT200h hybrid, Ford’s crucial new-generation Focus, the Volvo V60 wagon, Citroen’s DS4 prestige small car and Peugeot’s 508 medium-sized sedan.
However, the two French cars were close to being downgraded to four stars on account of unremarkable pedestrian protection and, if tested under new minimum pedestrian standards to be introduced next year, would have automatically lost a star.
The Lexus CT hybrid would also have been downgraded to four stars under the 2012 standard.
After Japan NCAP rated the Mitsubishi i-MiEV with a “creditable” four-star rating in February – the first independent NCAP assessment of a plug-in electric vehicle, in a result that also applies to the i-MiEV-based Citroen C-Zero and Peugeot i0n – Euro NCAP says the Leaf’s five-star (out of five) result now proves that electric vehicles can be as safe as mainstream cars.
The tests are carried out with ‘live’ batteries and the vehicle is exposed to the same test conditions as other cars in the program.
Euro NCAP also says special consideration is given to post-crash battery integrity and the proper functioning of the battery cut-off switch that isolates the high-voltage battery in the event of a crash.
The Leaf scored 89 per cent for adult occupant protection, 83 per cent for child protection, 65 per cent for pedestrian protection and 84 per cent in the ‘safety assist’ category, the latter assessing safety features such as electronic stability control, seatbelt reminders and speed limitation devices.
In comparison, the i-MiEV – which is an older design and a smaller (light-sized) car than the C-segment Leaf – scored 73 and 78 per cent respectively in the adult and child protection categories and only 48 per cent in pedestrian safety. It managed 86 per cent for ‘safety assist’.
“The Nissan Leaf proves that EVs can be equally safe as common cars,” said Euro NCAP secretary general Michiel van Ratingen. “The standard is now set for the next generation of cars on the European market.”The same five-star safety rating is expected for the Leaf when it arrives in Australia in the first quarter of next year, given the Australasian NCAP regime has virtually the same assessment criteria as its European affiliate.
The Leaf’s battery pack, which comprises 48 lithium-ion modules, is housed in a special compartment underneath the rear seats and is designed not to come into contact with occupants in a crash, and to eliminate the risks of battery damage and high-voltage leaks.
Euro NCAP said no electrical hazards or problems were encountered during any of the impact tests.
The vehicle lost points in terms of protection against adult whiplash injuries in a rear impact – rated as marginal – while the “stiff centre console and structures surrounding the steering column posed a risk of injury to the knees and femurs of occupants of different sizes to the dummies used in the test, or to those sat in different positions”.
Whereas car manufacturers previously shunned NCAP results, arguing the rigorous tests were unrealistic compared to the holistic approach taken with a vehicle’s design, Nissan has joined the increasing number of car-makers to highlight favourable ratings for particular models.
Nissan’s vice-president of vehicle design and development, Jerry Hardcastle, said the company was “not surprised” by the Leaf’s five-star rating and emphasised that the vehicle had “gone through more tests than any car we have ever produced”.
“On top of the conventional offset barrier and side impact tests, we have tested the electrical system in every way to ensure it can never be overcharged and that the isolation program works as intended in a crash,” he said.
The Toyota Prius-based Lexus CT200h petrol-electric hybrid scored an impressive 94 per cent for adult occupant protection, plus 84 and 86 per cent in the child and safety assist sections, but only 55 per cent for pedestrian safety.
NCAP said: “The front edge of the bonnet was poor in nearly all of the areas tested. In most areas likely to be struck by the head of a child, the bonnet offered a good level of protection but, while good in places, was rated as poor or marginal in most areas where an adult’s head might strike.”From 2012, Euro NCAP will increase the minimum requirement for pedestrian protection from 40 to 60 per cent, meaning Lexus will have to improve in this area for the CT200h to maintain its five-star rating.
The same applies to Citroen’s DS4, which achieved only 43 per cent for pedestrian protection and, as a result, was close to being downgraded to four stars. The front edge of the bonnet and adult head protection came in for particular criticism.
In other areas, the DS4 performed well, managing adult, child and safety assist scores of 90, 80 and 97 per cent respectively.
It was a similar case with the 508, which managed just 41 per cent for pedestrian protection, compared to 90, 87 and 97 per cent in the respective adult, child and safety assist categories.
Due for release in Australia in August, Ford’s new-generation Focus received ‘advanced reward’ billing with its Active City Stop and Lane Keeping Aid active safety and driver assistance systems, with the overall percentages for adult, child, pedestrian and safety assist coming in at 92, 82, 72 and 71 per cent respectively.
Protection of the lower legs of the driver was rated only as “adequate” and chest protection in the more severe side pole test was rated as marginal. While the overall pedestrian score was high, protection of an adult pedestrian’s head was rated as “poor or marginal” in most areas tested.
Ford of Europe chairman and CEO Stephen Odell described the recognition of its new technologies by Euro NCAP as “incredibly gratifying”.
Volvo’s high level of standard safety equipment – including the City Safety collision-avoidance system – led to a maximum 100 per cent score for the ‘safety assist’ category on the V60, and while the vehicle is also available with hi-tech pedestrian anti-collision technology, NCAP also took issue with level of adult pedestrian head protection.
As well as the soon-too-increase 40 per cent pedestrian protection minimum level, Euro NCAP’s current five-star rating requirements are 80 per cent (adult protection), 75 per cent (child) and safety assist (40).
