We evaluate the option of directly charging from the grid (option 1) against the installation of an intermediate battery (option 2). We perform a discounted cash flow analysis to calculate the payback period of the excess capital expense associated with option 2. We only consider the LFP battery chemistry which is more suitable for a stationary application compared to NMC. The life cycle of the LFP battery is 10 years and is used as the decision criterion for this analysis. A payback period longer than 10 years justifies option 1 and vice versa. Figure shows the payback period for scenarios covering a range of unit battery costs and demand charges. Based on Muratori et al. 75% of the demand charges for high-power charging applications are below 10 USD/kW. Therefore, in most cases, the intermediate battery is not justified for the current-day battery price of 100 USD/kWh because the payback period is greater than 10 years. However, regions such as Hawaii where demand charges exceed 12 USD/kW, would benefit from installing an intermediate battery. We also see that the economic feasibility of option 2 improves over time as battery prices are expected to decrease. In the long-term scenario, when LFP batteries are priced at 70 USD/kWh, we expect option 2 to take over.