THE BATTERY-TESTING facility at General Motors in Michigan is working 24 hours a day, seven days a week on the Chevrolet Volt, the electric car the company this week described as its "number one priority".
The US carmaker is developing the Volt and its still-unproven technology in parallel on one of its briskest development schedules ever.
It aims to start selling the car by late 2010 and, in so doing, wrestle industry leadership on environmental issues from Toyota, its arch rival.
GM has global ambitions for the Volt, which, unlike Toyota's Prius and other hybrid petrol-electric cars on the market, promises a 40-mile drive on pure electric power, and can be recharged at a cost of about $0.80.
The company premiered the plug-in Volt as a concept car in January 2007 in Detroit and began work on a production version within two months in an unusually determined effort that some company officials now describe as a "moon shot".
"This will be a global car - right-hand drive, left-hand drive, compliant with regulations everywhere," Bob Lutz, GM's vice-chairman of global product development, said as the company opened the programme's doors to media this week.
GM celebrates its centenary this year, but is on the verge of being eclipsed by Toyota on sales. It has dedicated about 200 engineers and 50 designers to the project.
The Volt is the "number one priority project we currently have within General Motors", said Frank Weber, heading the Volt effort. "Whatever it takes to execute this programme, we will do."
The vigour and aggressive timetable are uncommon in Detroit and attest to GM's desire to shake off its reputation as an environmental laggard after discontinuing its EV1 electric car that it developed in the 1990s.
However, the brisk time-table poses risks, notably the reliability of the advanced lithium-ion battery packs that will power the car which can malfunction if just one cell is damaged.
Toyota is developing its own plug-in hybrid vehicle using different lithium-ion technology, but has made no commitment to launching mass-market sales.
The Japanese carmaker sold more than 180,000 of its Prius cars in the US last year and claims some 80 per cent of global hybrid sales. It uses the Prius to promote its overall green credentials, to the irritation of GM and other rivals.
GM says the Volt will outclass the Prius with an extended range that approximates the average American commute.
To compress tests of the batteries over a 10-year life into just two years, GM is running battery-cycling equipment around the clock in Michigan and Germany. The batteries, being developed for GM separately by Germany's Continental and a subsidiary of South Korea's LG Chem, will soon be integrated into "mule" vehicles for on-road tests.
The 1.8-metre T-shaped battery pack, which extends along its spine between the Volt's rear passenger seats, is presenting GM's designers with special challenges, as is the need to improve the Volt's aerodynamics to reach the 40-mile range while keeping a sporty look.
GM's hand is being forced by America's tighter fuel-economy regulations and rising petrol prices. Nissan, Renault, Mitsubishi and Daimler's Smart brand are also developing electric vehicles.
GM contends its Volt is superior to pure electric cars because of its "range extender", an engine that backs up the electric motor when the batteries run low. "You can't walk to the gas station for a five-gallon can of electricity," says Mr Lutz.
As it develops the Volt, GM's main rival might again be Toyota, which is developing a plug-in hybrid vehicle with a longer pure-electric range than the Prius.
Toyota plans to launch fleet sales of plug-in cars by 2011 but says it does not want to proceed with mass-market sales until it is sure the batteries are reliable. -