Creating a Battery using azobenzene in High School
Azobenzenes are among the most widely studied molecular photoswitches, yet, I'm not sure this is a project capable of doing in a high school lab. It probably need sophisticated instruments (e.g., azobenzene needs to be covalently bound to carbon nanotubes (CNTs)) and has done previously, notably by Department of Materials Science and Engineering in Massachusetts Institute of Technology (MIT) (Ref.1). Yet, I'd encourage you to consult people who know the field (such as Prof. Timothy J. Kucharski at MIT and Harvard) and get some advice how to do it in a laboratory environment or do a oral presentation (that would be cool as well). I'll attached some figures of Ref.1 for your convenience here: 

Figure 1: Synthesis and characterization of azobenzene-functionalized SWCNTs (Adapted from reference 1. Copyright @ 2014 Nature Publishing Group).


Figure 2: Photochemical charging and thermal energy release (Adapted from reference 1. Copyright @ 2014 Nature Publishing Group).


Figure 3: Photochemical and thermal cycling (Adapted from reference 1. Copyright @ 2014 Nature Publishing Group).


Figure 4: Effect of packing photochemical switches in the solid state (Adapted from reference 1. Copyright @ 2014 Nature Publishing Group).


Also read Ref.2 for more information on molecular solar thermal energy storage using chemicals other than azobenzene, which also included.

References:


T. J. Kucharski, N. Ferralis, A. M. Kolpak, J. O. Zheng, D. G. Nocera, J. C. Grossman, “Templated assembly of photoswitches significantly increases the energy-storage capacity of solar thermal fuels,” Nature Chemistry 2014, 6, 441–447 (DOI: 10.1038/NCHEM.1918).
A. Lennartson, A. Roffey, K. Moth-Poulsen, “Designing photoswitches for molecular solar thermal energy storage,” Tetrahedron Letters 2015, 56(12), 1457–1465 (https://doi.org/10.1016/j.tetlet.2015.01.187).