Although LEAP can model energy storage it is usually more useful for modeling larger energy systems (cities, provinces, nations, etc). It sounds like you want to do more technically detailed engineering-based modeling. I would recommend you take a look at the HOMER platform, which I believe covers exactly this type of use case. Info on HOMER here: https://leap.sei.org/default.asp?action=tools&ID=23. You may also want to look at RETScreen: https://leap.sei.org/default.asp?action=tools&ID=17. Note: HOMER and RETSCreen are developed by other organizations (not SEI, the developers of LEAP).

Hope this helps - sorry for slow response.

Charlie