Adding an energy storage battery to a residential solar panel system typically costs $7,000 to $18,000. The final price depends on what you buy and who installs it. Clicking “Get Your Estimate” submits your data to All Star Pros, which will process your data in accordance with the All Star Pros Privacy Policy. What Is the Cheapest Solar Battery Brand? Budget-friendly options include LG RESU and BYD. . It costs about $11,000 to install solar batteries—how much you save depends on where you live. That's the promise of solar batteries —but at nearly $11,000. . This guide breaks down everything you need to know about solar battery pricing, installation, and savings across the United States.