This Perspective discusses the current status and future opportunities for polymer science in battery technologies. Polymers play a crucial role in improving the performance of lithium-ion batteries and will be even more important for sustainable and versatile post-lithium battery technologies, particularly solid-state batteries. The article identifies trends in the design and development of polymers for battery applications, including binders for electrodes, porous separators, solid electrolytes, and redox-active electrode materials. Examples include new ionic polymers, biobased polymers, self-healing polymers, mixed-ionic electronic conducting polymers, inorganic-polymer composites, and redox polymers. The future needs, opportunities, and directions of the field are highlighted. Polymers as electrode binders are essential for maintaining electrode structure and performance. They must have thermal, chemical, and electrochemical stability, flexibility, and strong adhesion. PVDF is commonly used but has environmental concerns. Alternatives like poly(ionic liquids) and biopolymers are being explored. For silicon anodes, self-healing and elastomeric polymers are needed. Multifunctional binders with ionic and electronic conductivity are also being developed. Porous separators are critical for battery safety and performance. Current separators are polyolefin-based but have limited wettability and thermal stability. Alternatives like PVDF and high-performance aramid nanofibers are being investigated. New separators with improved properties, such as electrolyte uptake and thermal stability, are being developed. Polymer electrolytes are key for solid-state batteries. PEO is widely used but has limitations in electrochemical stability and lithium transference number. Alternatives like poly(ionic liquid) electrolytes and sulfonamide anionic polymers are being explored. New electrolytes with improved ionic conductivity and sustainability are being developed. Inorganic-polymer composite electrolytes combine the advantages of inorganic and polymer materials. They offer high ionic conductivity and stability. Hybrid solid electrolytes, such as those combining oxide and sulfide-based electrolytes, are being developed. Redox polymers are gaining attention as sustainable electrode materials for new battery technologies. They offer high capacity and performance but face challenges in cycling stability and reliability. Redox polymers can be used as anodes and cathodes in symmetric batteries and are suitable for multivalent ions like Mg, Ca, or Al. Future directions include the development of sustainable and biodegradable polymers, dry electrode fabrication, and additive manufacturing for battery production. Artificial intelligence and machine learning are also being used for materials discovery in battery technologies. The field is expected to grow with new polymer materials and manufacturing processes.This Perspective discusses the current status and future opportunities for polymer science in battery technologies. Polymers play a crucial role in improving the performance of lithium-ion batteries and will be even more important for sustainable and versatile post-lithium battery technologies, particularly solid-state batteries. The article identifies trends in the design and development of polymers for battery applications, including binders for electrodes, porous separators, solid electrolytes, and redox-active electrode materials. Examples include new ionic polymers, biobased polymers, self-healing polymers, mixed-ionic electronic conducting polymers, inorganic-polymer composites, and redox polymers. The future needs, opportunities, and directions of the field are highlighted. Polymers as electrode binders are essential for maintaining electrode structure and performance. They must have thermal, chemical, and electrochemical stability, flexibility, and strong adhesion. PVDF is commonly used but has environmental concerns. Alternatives like poly(ionic liquids) and biopolymers are being explored. For silicon anodes, self-healing and elastomeric polymers are needed. Multifunctional binders with ionic and electronic conductivity are also being developed. Porous separators are critical for battery safety and performance. Current separators are polyolefin-based but have limited wettability and thermal stability. Alternatives like PVDF and high-performance aramid nanofibers are being investigated. New separators with improved properties, such as electrolyte uptake and thermal stability, are being developed. Polymer electrolytes are key for solid-state batteries. PEO is widely used but has limitations in electrochemical stability and lithium transference number. Alternatives like poly(ionic liquid) electrolytes and sulfonamide anionic polymers are being explored. New electrolytes with improved ionic conductivity and sustainability are being developed. Inorganic-polymer composite electrolytes combine the advantages of inorganic and polymer materials. They offer high ionic conductivity and stability. Hybrid solid electrolytes, such as those combining oxide and sulfide-based electrolytes, are being developed. Redox polymers are gaining attention as sustainable electrode materials for new battery technologies. They offer high capacity and performance but face challenges in cycling stability and reliability. Redox polymers can be used as anodes and cathodes in symmetric batteries and are suitable for multivalent ions like Mg, Ca, or Al. Future directions include the development of sustainable and biodegradable polymers, dry electrode fabrication, and additive manufacturing for battery production. Artificial intelligence and machine learning are also being used for materials discovery in battery technologies. The field is expected to grow with new polymer materials and manufacturing processes.