The accumulation of plastic waste represents both a global environmental crisis and a largely untapped source of carbon feedstocks. Electrocatalytic upcycling of polyethylene terephthalate (PET) has emerged as a promising energy-efficient strategy to convert plastic-derived ethylene glycol into value-added C 1 -C 2 chemicals, including glycolic acid and formic acid, under mild operating conditions. This review summarizes recent advances in electrocatalyst design for PET upcycling, including defect-engineered, single-atom catalyst, and heterostructured interfaces, with a focus on how catalyst structure regulates interfacial charge transfer, oxidation pathways, and product selectivity. Beyond catalyst development, we highlight integrated electrocatalytic platforms that couple PET-derived anodic oxidation with value-added cathodic CO 2 or nitrate reduction, thereby lowering cell voltage and enabling co-production of value-added chemicals (e.g., ammonia, cyclohexanone oxime). Insights from in situ spectroscopy and computational modeling elucidate critical structure-function relationships, while process-level analyses underscore scalability and energy efficiency. Finally, key challenges and future opportunities related to reactor design, energy efficiency, and scalability are outlined, positioning electrocatalytic plastic-to-chemicals refineries as a viable pathway toward circular carbon utilization and sustainable energy systems. Electrocatalytic upcycling of polyethylene terephthalate enables selective conversion of PET-derived intermediates into value-added C 1 and C 2 chemicals through advanced catalyst and paired-reaction engineering. • This review summarizes recent progress in electrocatalytic upcycling of polyethylene terephthalate into C 1 -C 2 chemicals. • Reaction pathways, key intermediates, and interfacial charge-transfer processes governing PET electro-oxidation are elucidated. • This review discusses structure-performance relationships of electrocatalysts and strategies for regulating activity and selectivity. • Integrated electrochemical energy-conversion platforms and paired electrolysis strategies for PET valorization are highlighted. • Challenges and future prospects toward energy-efficient plastic-to-chemicals electro-refineries are outlined.

Advanced additives have become a key strategy for pushing the practical limits of lithium-ion batteries (LIBs) by tuning not only electrode materials but the entire cell structure. Instead of being passive bystanders, modern additives are intentionally designed to participate in electrochemical reactions, buffer mechanical stress, regulate ion and electron transport, and form robust interphases. This review offers a comprehensive overview of how additives are used in anodes, electrolytes, and cathodes to improve energy density, rate capability, cycle life, and overall safety. We explain how tailored additives can stabilize active materials that undergo significant volume changes, facilitate the formation of thin, stable, and conductive interphases, and enhance Li⁺ solvation and transport, thereby mitigating lithium plating and side reactions. Special attention is given to multifunctional additives that provide structural reinforcement, redox activity, and interface engineering, along with the interplay between bulk modifications and surface design strategies. Finally, we discuss ongoing challenges, including compatibility with high-voltage chemistries, scalability, and performance in practical cell formats, and we propose future directions for data-driven, rational additive development. By viewing additives as active, designable components of the entire battery system, this review aims to support the development of advanced LIBs with improved durability, safety, and performance under real-world conditions. • Modern additives play an active role in electrochemical reactions, surpassing traditional passive functions. • Multifunctional additives enhance structural integrity, exhibit redox activity, and stabilize interfaces. • Customized additives enhance energy density, improve rate capability, extend cycle life, and increase battery safety. • Data-driven design strategies facilitate the rational integration of both bulk and surface modifications for the effective development of high-voltage LIBs.