In addition to quinones and free radicals, organic active materials include a wide range of compounds that can be used in organic redox flow batteries. These materials include polymers, conjugated oligomers, and small organic molecules with redox activity. Their high energy density, long cycle life, and low cost make them attractive for large-scale energy storage applications. Organic active materials can be tailored to meet specific performance requirements, such as enhanced conductivity and stability. Their versatility and sustainability contribute to the advancement of redox flow battery technology.