The electric vehicle (EV) battery swapping station offers convenient battery replacement services and shows significant potential for participating in energy and frequency regulation auxiliary service markets. However, frequent charge-discharge cycles accelerate battery degradation, shortening battery life and increasing operational costs. To enhance overall profitability, this paper proposes a two-stage optimization strategy. In the first stage, the station's adjustable resources are better aligned with market demand by incentivizing EV battery swap demand and optimizing the number of spare batteries and scheduling. In the second stage, a battery aging model is integrated to coordinate the optimization of EV power dispatch and frequency regulation capacity, balancing battery degradation with market revenue. Simulation results show that the proposed strategy effectively increases the profitability of the battery swapping station and extends battery life, demonstrating substantial practical value.