Beyond Traditional Batteries—Emerging Systems for Next-Generation Energy Storage

Against the backdrop of the global energy transition, new energy battery technology plays an increasingly vital role in modern society, effectively addressing the intermittency of energy sources [1,2,3]. With the rapid development of electric vehicles, energy storage power stations, and other sectors, market demand for new energy batteries continues to grow, simultaneously driving continuous innovation and breakthroughs in this technology. Driven by both technological advancement and market demand, new energy battery technology is evolving toward higher energy density, longer lifespan, lower cost, and enhanced safety [4,5]. While traditional batteries have powered the modern era of portable electronics and electric vehicles, their inherent limitations in material scarcity, energy ceiling, and safety concerns have catalyzed the exploration of novel battery chemistries and architectures [6].

This Special Issue entitled “Breakthroughs in Conventional Electrochemical Energy Storage Systems,” brings together pioneering research and insightful reviews that highlight the rapid progress in next-generation battery systems. We present seven original research articles and one review article collectively examining the design, mechanisms, and performance of emerging battery technologies. Several studies focus on developing advanced electrode materials capable of achieving higher specific capacities and improved ionic conductivity. Others employ advanced modeling techniques to address battery aging and safety concerns. Battery aging prediction and thermal safety assessments provide theoretical foundations for designing and deploying highly safe, long-life batteries. The review article explores the potential of metal–air batteries as range extenders for electric vehicles, highlighting ongoing research into cycle life and material stability to enable their widespread adoption in EVs and other energy storage applications. We are encouraged that these studies not only demonstrate significant performance improvements but also discuss the challenges they face. These insights are crucial for guiding the transition from laboratory to commercially viable technologies.

Research Paper:

• Advanced Electrode Materials

Zeng et al. (contribution 1) prepared a ternary CoMnAl layered double hydroxide (LDH) cathode for aqueous zinc-ion batteries via a simplified coprecipitation method. The introduction of trivalent Al³⁺ ions interacting strongly with Mn³⁺ ions effectively modulated the electronic structure, reduced the redox energy barrier, and enhanced structural stability. Characterization revealed a high specific surface area (106.530 m²·g⁻¹) and abundant nanopores, facilitating ion transport. Electrochemical testing revealed a high specific capacity of 238.9 mAh g⁻¹ at a current density of 0.5 A g⁻¹, excellent rate performance, and outstanding cycling stability, achieving a capacity retention of 92% after 2000 cycles. This study provides an effective strategy for designing high-performance, long-life AZIB cathode materials.

Chen et al. (contribution 2) fabricated a hierarchical porous electrode with conformal ultrathin α-VO₂ nanosheets on foam nickel via a cost-effective hydrogen bubble template method and electrodeposition for high-power miniature lithium-ion batteries. This unique structure provides continuous electronic conduction pathways and short ionic diffusion channels, enabling rapid reaction kinetics. This design significantly enhances the electrode’s kinetic performance. The optimized electrode achieves a high areal energy density of 0.49 mAh cm⁻² at 1 mA cm⁻² and an ultra-high power density of 410 mW cm⁻² at 250 mA cm⁻², with a capacity retention rate approaching 100% after 700 cycles. Microbatteries assembled with this electrode can power an electronic clock continuously for over 18 h, retaining 75% of its initial capacity after 180 cycles. This research provides an effective pathway for developing high-performance, low-cost, and easily integrated micro-energy storage systems.

Oladapo et al. (contribution 3) proposed enhancing magnesium-ion battery performance by optimizing magnesium alloy anodes (Mg-Al and Mg-Ag). Cyclic voltammetry and electrochemical impedance spectroscopy tests were conducted at a constant temperature. Results indicated that the Mg-Al alloy demonstrated superior stability during cycling, with a voltage drop of only 0.05 V after 100 cycles and energy efficiency maintained above 85%. while the Mg-Ag alloy experienced a 0.12 V voltage drop and energy efficiency decreased to 80%. The addition of Al aids in forming a surface protective layer, suppressing passivation and degradation, thereby reducing internal resistance growth and extending battery lifespan. This research provides crucial evidence for further optimization of magnesium alloy anodes and the commercialization of magnesium batteries.

Zhang et al. (contribution 4) proposed a novel Se quantum dot@CoFeO_x (Se-FeO_x-Co) composite nanomaterial as a highly active and stable cathode catalyst for rechargeable zinc-air batteries (ZABs). The catalyst was synthesized via a one-pot hydrothermal method, featuring Co-doped iron oxide nanosheets decorated with Se quantum dots. It exhibited outstanding oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalytic activity under alkaline conditions, with a potential difference as low as 0.87 V. Furthermore, liquid zinc–air batteries assembled with this cathode achieved a high open-circuit voltage of 1.46 V and a discharge specific capacity of 391 mAh·g⁻¹. They also demonstrated remarkable durability, maintaining stable performance over 800 min of operation, showcasing significant potential for practical energy storage applications.

2.

Advanced Modeling Techniques

Tulabi et al. (contribution 5) addressed the safety issue of thermal runaway (TR) in lithium-ion batteries by establishing an electrochemical–thermal coupled model that accounts for aging effects. This model enables more precise prediction of thermal behavior and TR triggering in cylindrical batteries. Full factorial design and analysis of variance (ANOVA) revealed aging’s dual effects: increased internal resistance exacerbates temperature rise, elevating TR risk; whereas capacity decay mitigates risk by reducing stored energy. Furthermore, a logistic regression algorithm identified an internal resistance threshold for TR occurrence with 95% prediction accuracy. This work provides an effective framework and insights for understanding the thermal behavior of aged batteries, optimizing thermal management, and developing early warning systems.

Hammou et al. (contribution 6) compared the performance of three recurrent neural networks (RNN, LSTM, and GRU) in multi-step lithium-ion battery state-of-health (SoH) prediction. The results demonstrated that the GRU model achieved high prediction accuracy, with its mean absolute percentage error maintained below 3%. It exhibited stable performance in multi-step forecasting and featured lower computational complexity than the LSTM model, making it highly suitable for resource-constrained in-vehicle environments. This indicates that leveraging temperature—an easily monitored feature—in conjunction with GRU networks enables accurate and efficient prediction of battery aging states.

Hüger et al. (contribution 7) investigated the chemical diffusion coefficient and tracer diffusion coefficient of lithium in sintered LiCoO₂ (LCO) disks. By comparing electrochemical methods (EIS, PITT) with isotope tracing (SIMS), they found that diffusion coefficients measured by electrochemical methods exhibited an extremely wide range (10⁻⁹–10⁻²⁸ m²/s), significantly influenced by model selection, parameter settings, and electrode charge state. In contrast, SIMS measurements extrapolated from high-temperature data to room temperature yielded a stable tracer diffusion coefficient of approximately 10⁻²² m²/s. The study indicates that relying solely on electrochemical methods is insufficient for obtaining accurate lithium diffusion coefficients, necessitating calibration using direct tracer techniques like SIMS. SIMS results narrow the credible range of lithium diffusion coefficients to 10⁻²¹–10⁻²² m²/s, providing more reliable diffusion parameters for subsequent material design and battery performance optimization.

3.

Review Article

Metal–air batteries have garnered significant attention due to their high theoretical energy density, low cost, and abundant materials. Shabeer et al. (contribution 8) comprehensively compared the potential of various metal–air batteries (MABs) as range extenders for electric vehicles (EVs). Zinc-air batteries are currently the only commercialized technology, offering cost and safety advantages; aluminum–air batteries feature high energy density but suffer from severe anode corrosion; lithium-air batteries demonstrate outstanding theoretical performance but face development constraints due to complex multiphase reactions and electrolyte decomposition issues. Comprehensive analysis indicates that no metal–air battery technology is currently fully mature. They primarily serve as auxiliary power sources, complementing main batteries to extend range and alleviate range anxiety. This review highlights that through electrolyte optimization, electrode material innovation, and system engineering integration, metal–air batteries hold promise as a key technology to advance electric vehicle adoption and drive low-carbon transportation transformation.

As global demand for efficient and sustainable energy storage continues to grow, coupled with the depletion of fossil fuel and natural gas reserves, the role of innovative battery energy storage systems becomes increasingly vital [7,8]. This Special Issue provides a timely platform for knowledge exchange and collaborative innovation, advancing the development of batteries that are not only more powerful and durable, but also more environmentally friendly. We extend our sincere gratitude to all authors, reviewers, and editors who contributed to the success of this publication. We hope this collection will inspire further research and collaboration, accelerating the emergence of next-generation energy storage solutions.