As more renewable energy has come onto the grid, it has become increasingly important to find ways to manage the intermittency of these resources. One primary resource that is increasingly being deployed to manage existing and proposed generation is energy storage. Energy storage, which encompasses a wide range of technologies, can supply energy during peak load and help make intermittent resources dispatchable. In addition, the resource can provide key services to the grid. With this in mind, policymakers, companies, and other stakeholders have increasingly seen energy storage as a key part of transforming the energy industry in the coming decades. However, the industry has only recently started to see increased energy storage deployment and investment, and longer duration storage technologies are still not widespread.