Batteries are reshaping power systems in the US and China, offering a clean alternative to fossil fuel-powered peaker plants. California's battery fleet set a new record by discharging 11.2 GW during peak demand, while China plans to significantly increase battery storage capacity and reduce natural gas use by 70% by 2035. The US has seen rapid growth in battery storage, with federal policies and incentives supporting the transition away from peakers. Experts suggest that prioritizing battery storage over fossil peaker plants can accelerate clean energy goals, establish market mechanisms, and solidify global leadership in the industry. By shifting to battery storage, both countries can achieve a clean and flexible grid while reducing pollution and dependence on fossil fuels.