To enable the transition from fossil fuels to clean energy, efficient energy storage is necessary. We need energy storage to support two primary use cases: a modern, robust power grid and clean transportation. To support these use cases, we require novel materials that are earth abundant, widely available, and inexpensive. We also need them to be incorporated into energy storage systems that have high capacity, long durability, are easily recyclable, and are safe. At SSRL, we are using x-rays to study energy storage materials and systems such as rechargeable Li-ion batteries and hydrogen fuel cells. We are also exploring future solutions such as alternative battery technology like Na-ion and Li-metal batteries. The x-rays from SSRL can probe inside working devices to identify and understand the key degradation mechanisms that result in reduced device performance and eventual failure. Additionally, we use the x-rays to study the performance of novel energy storage materials and methods for scaling up materials synthesis to increase yields and reduce manufacturing costs.