I'm working on a project that will use a photovoltaic panel as the primary source to drive a power LED array for interior lighting. My idea is to incorporate a storage battery to provide a stable power supply for the load (i.e. maintain a steady supply when clouds roll by) and to allow the load to be driven after the sun goes down. I'd also like to be able to drive the LED array directly once the battery is fully charged, but setting it up so that the battery is in series with the load seems like it will simplify the design of the voltage regulation circuitry, as well as eliminating the need to switch the direction of power flow from the solar panel. Anybody have any suggestions for me? Thanks a bunch.