https://www.cnet.com/roadshow/news/electrify-america-tesla-powerpack-batteries-charging-stations/

 "With our chargers offering high power levels, it makes sense for us to use batteries at our most high demand stations for peak shaving to operate more efficiently," said Giovanni Palazzo, CEO of Electrify America, in a statement. "Tesla's Powerpack system is a natural fit given their global expertise in both battery storage development and EV charging."

Tesla's Powerpack batteries are basically massive boxes housing multiple smaller battery pods. They're infinitely scalable, so they can provide power for an operation of just about any size. Reducing grid reliance during peak times will help Electrify America keep its costs in line.