I don't make pound cake much. Does anyone know how many batches I would need of a typical pound cake recipe for a 10" square pan? Also, if I recall, do I only fill the pan half full with the batter?

Figure out how many cups of batter your recipe makes. Then fill your pan with water and find out how many cups it holds. Compare the two. OBTW, I like a thicker cake so I fill my pans 2/3. This way if it rises above the top of pan I can just trim level with the top of pan.