Good morning,
In addition to the link that Paul sent, here is some additional information. The battery model is set to allow charging from PV or grid, and to discharge to meet some electric load. What type of analysis are you looking to conduct? Typically for behind-the-meter applications, the battery serves to discharge power to meet the electric load during portions of the day when electricity is more expensive, either from a energy or power standpoint. Without an electric load, a behind-the-meter battery has limited applications. One possible application may be to store PV power and sell to the grid at a more valuable time without ever serving an electric load; however, this is not supported in the current battery model.
Thanks,
Nick