The shift in pricing, according to some reports, is the result of an increase in manufacturing volume and subsequent decrease in production costs. As such, it's expected to be a long-term adjustment rather than a short-lived promotion.
Japan's National Institute for Technology and Evaluation (NITE) tested a Lithium Ion battery about the size of one used in a cellphone. It was struck with a hammer then left on a work bench, unconnected from any apparatus. The result was explosive.