Perhaps eventually we can use some of those superalloys used by NASA and other ultra-high tech organizations in very small quantities, where a very large atom is introduced into the lattice to increase energy required for dislocations. Of course, dislocations themselves can be utilized to strengthen a material, while reducing it's strength to weight ratio. Many interesting possibilities in this field.
As for lithium batteries, I prefer that beyond the immediate future we move past Li-ion to more energy dense battery tech. I know there have advancements like lithium-air that might make it to mass-production some time soon, but the limits of lithium batteries will be reached before too long. Even more interestingly, we can start seriously looking into deployment of wireless electricity to reduce the need for batteries in the first place.