Describe the bug
In cmod_battery, "capacity_factor" defaults to zero when not specified. As standalone battery has no technology module before cmod_battery, this results in a capacity factor of 0 which leads to divide by zero error in the initialization of capacity factor in the battery module.

To Reproduce
Steps to reproduce the behavior:

1. Go to Standalone Battery Case
2. Click Simulate
3. Search 'capacity' in Data Tables
4. See NaN

Expected behavior
Capacity factor based on gen would be negative for a standalone battery. Capacity factor based on gen sales would be positive