The solar cell and battery industries have advanced significantly over the past ten years.   The cost of photovoltaic electricity for example has dropped by a factor of ten.  Yet, there is still a lot that these technologies cannot do.  Over the past decade, my group has worked to develop nanocrystal chemistry with an ultimate goal of creating portable and essentially free energy, utilizing light harvested by solar cells embedded in the environment and electricity stored in batteries.  The creation of new materials and devices with new form factors are needed to meet these goals.  This talk will highlight several of our efforts.  We have fabricated paper solar cells made using copper indium diselenide (CuInSe2) nanocrystals as a printed semiconductor absorber layer on nanocellulose.  These solar cells are extremely lightweight and mechanically flexible—even foldable across the active area of the device—and inexpensive to manufacture with the potential to power a variety of Internet-of-Things (IoT) devices.  We have worked to develop silicon and germanium nanowires for high charge capacity lithium (and sodium) ion batteries.  I will discuss our current understanding of these materials and the use of in situ transmission electron microscopy to better understand their properties.  I will also discuss our recent work on metal halide perovskite nanocrystals and the use of superlattice assemblies to better understand their properties of these materials and perhaps make better solar cells.