The advent and expansion of hybrid technology has forced some additional markets to do some soul searching (or innovation as it's commonly called :P).
In order to have the scale of hybrids expected to hit the streets we require a battery that will accommodate the push and pull of driving. There aren't too many options out there so you can expect that car manufacturers are going to (they most certainly are) work hard to come up with better and more efficient solutions.
Currently the nature of hybrid technology is getting lighter and smaller, they keep charges longer and have a greater capacity.
The most prominent resource, currently, for hybrid batteries (which would be the primary method of storing energy) is a mixture called Nickle metal hydride. However, there are alternatives, one such alternative is lithium. Manufacturers are always looking for ways to expand the capability of hybrid batteries, lithium may be one of the answers.
Demand in the lithium market is generally fixed to a handful of major industrial players. Car manufacturers have kicked the tires on lithium, but currently the demand and expectations for increased immediate demand hasn't shot up.
We can expect two things. Lithium will increase in price as demand increased and the mostly fixed supply dwindles. But you can expect additional technologies to emerge using different metals in hybrid batteries.