Lithium and VRLA batteries requie different models. How does Homer manage these difderences
Hi Kevin - great question.
HOMER has several different battery models to be able to accurately represent the different chemistry / function.
The "idealized model" is used for Li-Ion batteries, and assumes a flat capacity curve.
The "kinetic model" is used for Lead Acid batteries, because it models the battery as if it were two storage tanks - an 'available' and a 'bound' storage tank, which are connected by a small connection 'pipe'. This effectively reduces the capacity at high charge/discharge rates. Like you said, after a battery has been discharged, it takes some time before the battery is functionally fully recharged. Let me know if that doesn't make sense.
Additionally, the most accurate/complicated "modified kinetic model" can be used for either type of battery and can include rate dependent losses, temperature dependence on capacity, cycle lifetime estimation, and temperature effects on calendar life.
And, just so you know, there are two other storage models: one for flywheels and one for a storage system where the cell stack and electrolyte can be sized and replaced independently.
Hope that helps,