Editorial: Reviews in batteries and electrochemistry volume II

Abstract

A central theme is safer battery design through material and structural innovation. Myeong et al. introduce a fire-extinguishing current collector coated with melamine polyphosphate (MPP) for lithium-ion batteries. Their work demonstrates that integrating a flame-retardant layer directly onto the Al current collector can reduce self-extinguishing time while preserving electrochemical performance when the coating composition is properly optimized. Rather than relying on bulk electrolyte reformulation, this strategy localizes safety functionality at the electrode architecture level. The study is notable for showing that the current collector can act not only as a passive conductor but also as an active safety component. This concept aligns well with growing efforts to design multifunctional battery components that improve abuse tolerance without sacrificing performance.A complementary safety-focused contribution is provided by Wang et al., who engineer a composite solid-state electrolyte (CSSE) for sodium metal batteries using a PVDF matrix and NASICON-type Na3.7Zr1.45Sc0.4Mg0.15Si2PO12 filler. Their optimized electrolyte establishes multiple ion-transport channels and achieves improved room-temperature ionic conductivity, sodium-ion transference number, and interfacial compatibility. Importantly, the resulting full cells show strong capacity retention and long-term cycling stability. This work highlights how solid-state sodium batteries are maturing through interfacial design rather than conductivity improvements alone. It also underscores sodium's growing relevance as a lower-cost alternative to lithium in stationary and potentially transport applications.On the theme of materials discovery for next-generation chemistries, Tham et al. present a high-throughput computational screening framework for zinc-rich cathodes for anode-free aqueous zinc batteries. By down-selecting from more than 1000 candidates using criteria including thermodynamic stability, conductivity, voltage window, aqueous stability, and diffusion kinetics, the authors identify six promising compounds. Their study exemplifies how firstprinciples databases and structured screening pipelines can accelerate the search for viable electrode materials in emerging chemistries. Beyond identifying candidates such as ZnNi5Zn4MnO5, the work contributes design rules linking composition and performance, which may guide future experimental validation and broader battery materials discovery.If Tham et al. show the power of computational selection, Khan's mini-review on sodium-ion batteries (SIBs) provides a broader perspective on why sodium systems continue to attract attention. The review emphasizes sodium abundance, low cost, and relevance for large-scale storage, while also discussing persistent limitations such as the larger Na + ionic radius, volume change, sluggish kinetics, and unstable solid-electrolyte interphase formation. Though concise, the review captures the key message that sodium-ion batteries remain highly promising but still require coordinated advances in cathodes, anodes, electrolytes, and separators before reaching full commercial maturity.Processing science is another major thread in this collection. Lee et al. compare dry and wet coating methods for Ni-rich NCM811 cathodes, showing that coating route strongly affects surface degradation and ultimately cell durability. Their results reveal that wet coating, despite being conventional, promotes formation of a NiO-like surface phase through water exposure, which accelerates cation mixing and resistance growth. By contrast, dry coating suppresses this unwanted phase formation and delivers better capacity retention and rate capability. This study is particularly timely because manufacturing methods are becoming just as important as composition in the commercialization of high-Ni cathodes. The work reminds us that performance losses can originate not only from intrinsic material instability but also from process-induced surface chemistry.At the system level, Madani et al. offer an expansive review of digital twin technologies for battery systems, charting the emergence of virtual battery replicas that integrate physics-based modeling, machine learning, cloud-edge computing, and battery management functions. Their review spans applications in electric vehicles, stationary storage, production, thermal management, state estimation, predictive maintenance, fault diagnosis, and end-of-life handling. It also usefully frames digital twins as multiscale entities-from cell materials to pack and grid systems-and identifies barriers such as standardization, cybersecurity, computational load, and data quality. Among the most important messages of this review is that future battery performance will not be determined by electrochemical materials alone, but also by the intelligence of the digital infrastructure that monitors and controls them throughout their lifecycle.Taken together, these papers reveal several clear directions for the field.First, interfaces remain decisive. Whether in Ni-rich layered oxides, sodium metal solid-state cells, or flame-retardant current collectors, interfacial chemistry controls not only capacity fade but also safety and abuse response.Second, processing matters as much as composition. The dry-vs-wet coating study demonstrates that subtle differences in synthesis route can produce major changes in surface phase evolution and electrochemical behavior. This principle applies broadly across battery manufacturing.Third, sodium and zinc chemistries are gaining strategic importance. Sodium-ion and sodium metal systems offer resource and cost advantages, while zinc-based systems open pathways toward aqueous and potentially safer batteries. Both areas are benefitting from improved modeling, materials screening, and interface engineering.Fourth, digitalization is becoming foundational. Digital twins connect electrochemistry with sensing, prediction, and operational control, creating opportunities for smarter charging, improved health estimation, and lifecycle optimization. As battery deployment scales, these system-level tools will be essential.Overall, this set of articles captures a battery community moving beyond isolated component optimization toward integrated design across materials, processes, architectures, and cyberphysical control. The future of advanced batteries will likely belong to approaches that combine these domains: safer interfaces, scalable manufacturing, chemistry-aware materials discovery, and intelligent management systems. These contributions offer strong examples of that transition and point toward a more holistic and application-ready era in electrochemical energy storage.