Although General Motors (GM) might prefer to test its Chevy Volt batteries over a ten-year period, the giant automaker says it’s ready and able to do the next best thing. Its newly-opened battery lab, said to be “the largest and most technologically advanced battery lab in the United States,” could enable GM to do the kind of accelerated testing that it will need to get the Volt out the door for its planned 2010 rollout.
Equipped with 160 test channels and 42 thermal chambers, the lab, which opened last week, is intended to duplicate extreme real-world driving patterns, hot and cold temperatures and calendar life.
Since the beginning of the Volt program, GM engineers have been concerned about whether the car’s short development schedule will allow them to do the kind long-term testing in everyday conditions that they’d like to do on the Volt’s lithium-ion battery pack.
“The big risks we have to overcome if we expect to see widespread implementation are quality, reliability, and durability,” said Mark Verbrugge of General Motors in an interview with Design News in 2008. “We’d like to get at least three to four years (of testing) on these batteries.”
GM hopes the new lab will enable its engineers to put the new battery packs through their paces on the short time schedule. The 33,000-square-foot lab will be used by more than a thousand engineers working on advanced batteries. It will include a thermal shaker table for structural integrity testing, a battery tear-down area for failure analysis, and an integrated test automation system.
The question remains whether the accelerated testing in the lab will give GM engineers the information they need.
“People try to take the results of accelerated testing and extrapolate them to a much longer lifetime under normal use,” said Elton Cairns, the head of Lawrence Berkeley National Laboratory’s Electrochemical Technology Group, in an interview with Design News earlier in 2009. “But unless the failure mechanisms are the same in both kinds of testing, you don’t really know how to extrapolate those results to real-world time. That’s the big pitfall. You can’t afford not to do stress testing. But on the other hand, it’s not very clear how you should interpret the results.”