> Panasonic would NOT pay additional money in licensing to make less money by having their batteries last longer.
> Large companies like this make sure the batteries they use aren't interchangable or standardized
Li-Ion cells are made in a variety of standard sizes: http://en.wikipedia.org/wiki/Battery_sizes#Round_lithium-ion.... I happen to own a couple of individual 18650 cells, and Panasonic and a number of other companies supply these cells to battery pack manufacturers wholesale.