Key Takeaways & Executive Findings
- •• This review explores the application of quasi-solid gel electrolytes (QSGEs) in alkali metal batteries (AMBs), emphasizing self-healing gels, flexible gels, biomimetic gels, and biomass gels. Each of these gel types brings unique advantages to the performance of AMBs. • This review outlines future research directions, including synthesizing advanced QSGEs, in situ characterization techniques, and theoretical simulations to better understand and optimize these materials. It identifies critical areas for investigation, guiding researchers to optimize QSGEs in AMBs and enhance their application. • QSGEs offer a promising strategy to address safety and durability concerns in AMBs, particularly for smart wearable devices, by providing self-healing, flexibility, and environmental friendliness. • The review highlights the need for enhancing ionic conductivity, mechanical strength, and environmental stability of novel gel materials to further improve AMB performance.
Abstract
Alkali metal batteries (AMBs) have undergone substantial development in portable devices due to their high energy density and durable cycle performance. However, with the rising demand for smart wearable electronic devices, a growing focus on safety and durability becomes increasingly apparent. An effective strategy to address these increased requirements involves employing the quasi-solid gel electrolytes (QSGEs). This review focuses on the application of QSGEs in AMBs, emphasizing four types of gel electrolytes and their influence on battery performance and stability. First, self-healing gels are discussed to prolong battery life and enhance safety through self-repair mechanisms. Then, flexible gels are explored for their mechanical flexibility, making them suitable for wearable devices and flexible electronics. In addition, biomimetic gels inspired by natural designs are introduced for high-performance AMBs. Furthermore, biomass materials gels are presented, derived from natural biomaterials, offering environmental friendliness and biocompatibility. Finally, the perspectives and challenges for future developments are discussed in terms of enhancing the ionic conductivity, mechanical strength, and environmental stability of novel gel materials. The review underscores the significant contributions of these QSGEs in enhancing AMBs performance, including increased lifespan, safety, and adaptability, providing new insights and directions for future research and applications in the field.
1. Introduction
In today’s society, the urgent need for sustainable energy solutions to mitigate the energy crisis and environmental pollution has intensified the focus on advanced battery technologies [1–10]. Since the 1970s, lithium battery technology has rapidly advanced, thanks to its high energy density of nearly 300 Wh kg−1 and long cycle life [11, 12]. Lithium’s low electrode potential (−3.04 V vs. standard hydrogen electrodes) and high specific capacity (3860 mAh g−1) have spurred extensive research [13, 14]. Lithium metal batteries (LMBs) have become the preferred energy storage solution for mobile electronic devices and electric vehicles. However, LMBs face challenges such as high costs, uneven lithium distribution, and safety issues like overheating, which can cause fires or explosions [15–18]. Lithium is also relatively scarce, making up only 0.0017 wt% of the Earth’s crust, and its extraction poses environmental concerns [19].
To address these issues, research has shifted toward sodium metal batteries (SMBs). Sodium is abundant (2.36 wt% in the Earth’s crust) and offers lower material costs [20, 21]. Sodium anodes provide high theoretical capacities with a low redox potential of −2.71 V [22]. While their energy density is lower compared to LMBs, most researchers believe that sodium-based batteries perform better at low temperatures compared to lithium-based batteries due to the smaller Stokes diameter of sodium ions, which allows for higher ionic conductivity in an electrolyte of the same concentration [23]. SMBs also have unique advantages, such as lower costs and resource abundance, which make them attractive as a supplement to lithium-ion batteries for electric vehicle applications. Potassium batteries are another emerging area of interest. Potassium is plentiful (2.09 wt% in the Earth’s crust) and inexpensive. Potassium anodes also deliver high theoretical capacities and a low redox potential of −2.93 V, offering a potential cost advantage [24]. In summary, lithium, sodium, and potassium batteries, known collectively as alkali metal batteries (AMBs), utilize ion migration for energy storage and release. Their varying capacities and resource availability present promising options for future energy storage solutions.
The primary challenges associated with AMBs stem from the suboptimal performance of electrode materials and the deficient characteristics of their corresponding electrolytes, which collectively impede compatibility and reduce overall efficiency.
Loading authentic research manuscript (Pages 1–5)...
Jiahui Lu, Yingying Chen, Yaojie Lei, Pauline Jaumaux, Hao Tian, Guoxiu Wang (2025). Quasi-Solid Gel Electrolytes for Alkali Metal Battery Applications. Nano-Micro Letters. https://doi.org/10.1007/s40820-024-01632-w
Research & Educational Purpose Only:The translations, structured abstracts, analytical annotations, and data reports provided by SinoTechIntel are intended exclusively for academic research, internal corporate R&D, and educational benchmarking. They do not constitute formal engineering, chemical safety, legal, or professional advice.
Copyright & Intellectual Property Notice: Original copyright of the underlying source articles and experimental data remains with the respective authors, institutions, and original publishing journals. SinoTechIntel claims intellectual property only over its proprietary translations, analytical syntheses, and AEO structured enhancements in accordance with international fair use and academic citation principles.
Frequently Asked Questions
What are quasi-solid gel electrolytes (QSGEs) and why are they important for alkali metal batteries?
QSGEs are gel-based electrolytes that combine the high ionic conductivity of liquid electrolytes with the mechanical stability of solid electrolytes. They are important for alkali metal batteries because they enhance safety by reducing leakage and flammability, while also providing flexibility and self-healing capabilities, which are crucial for wearable and flexible electronics.
What types of quasi-solid gel electrolytes are reviewed in this paper?
The review focuses on four types of QSGEs: self-healing gels, flexible gels, biomimetic gels, and biomass-derived gels. Each type offers unique advantages such as prolonged battery life, mechanical flexibility, high performance inspired by nature, and environmental friendliness.
How do self-healing gels improve battery performance?
Self-healing gels can repair internal damage or cracks that occur during battery cycling, thereby prolonging the battery's lifespan and enhancing safety by preventing catastrophic failures. This self-repair mechanism helps maintain ionic conductivity and electrode-electrolyte contact over extended use.
What are the future research directions for QSGEs in alkali metal batteries?
Future research directions include synthesizing advanced QSGEs with improved ionic conductivity, mechanical strength, and environmental stability. Additionally, in situ characterization techniques and theoretical simulations are needed to better understand the structure-property relationships and optimize these materials for practical applications.
Why are alkali metal batteries (AMBs) considered promising for future energy storage?
AMBs, including lithium, sodium, and potassium batteries, offer high energy density and long cycle life. Sodium and potassium are abundant and low-cost, making them attractive alternatives to lithium. Their varying capacities and resource availability provide options for diverse applications, from portable devices to electric vehicles and grid storage.
Related Technical Papers & Translations
Direct Repair of the Crystal Structure and Coating Surface of Spent LiFePO4 Materials Enables Superfast Li-Ion Migration
The rapid accumulation of spent LiFePO4 (LFP) cathodes from retired lithium-ion batteries necessitates the development of effective and environmental-friendly recycling strategies. In this context, direct regeneration has emerged as a promising approach for reclaiming LFP cathode materials, offering a streamlined pathway to restore their electrochemical functionality. We report an integrated regeneration protocol that simultaneously repairs the degraded crystal structure and reconstructs the damaged carbon coating in spent LFP. The regenerated cathode material had superfast lithium-ion diffusion kinetics and a stable cathode–electrolyte interface, giving a remarkable rate capability with specific capacities of 122 mAh g−1 at 5C and 106 mAh g−1 at 10C (1C = 170 mA g−1). It also maintained capacities of 110.7 mAh g−1 (5C) and 84.1 mAh g−1 (10C) after 400 cycles. It could be used in harsh environments and could be stably cycled at subzero temperatures (−10 and −20 °C) and in solid-state electrolyte batteries. Life cycle assessment combined with economic evaluation using the EverBatt model reveals that this direct regeneration approach has high economic and environmental benefits.
Oxide Semiconductor for Advanced Memory Architectures: Atomic Layer Deposition, Key Requirement and Challenges
Oxide semiconductors (OSs), introduced by the Hosono group in the early 2000s, have evolved from display backplane materials to promising candidates for advanced memory and logic devices. The exceptionally low leakage current of OSs and compatibility with three-dimensional (3D) architectures have recently sparked renewed interest in their use in semiconductor applications. This review begins by exploring the unique material properties of OSs, which fundamentally originate from their distinct electronic band structure. Subsequently, we focus on atomic layer deposition (ALD), a core technique for growing excellent OS films, covering both basic and advanced processes compatible with 3D scaling. The basic surface reaction mechanisms—adsorption and reaction—and their roles in film growth are introduced. Furthermore, material design strategies, such as cation selection, crystallinity control, anion doping, and heterostructure engineering, are discussed. We also highlight challenges in memory applications, including contact resistance, hydrogen instability, and lack of p-type materials, and discuss the feasibility of ALD-grown OSs as potential solutions. Lastly, we provide an outlook on the role of ALD-grown OSs in memory technologies. This review bridges material fundamentals and device-level requirements, offering a comprehensive perspective on the potential of ALD-driven OSs for next-generation semiconductor memory devices.
Laser powder bed fusion of biodegradable Zn-4Cu alloy: Processing, microstructure and properties
Zn's natural degradability and biocompatibility make it a promising candidate for implants, however, its mechanical properties remain insufficient for bone applications. In this study, the performance of Zn was enhanced by developing Zn-Cu alloys via laser powder bed fusion (LPBF). Optimal LPBF parameters for forming stable tracks were achieved by adjusting laser power and scanning speed. Under optimized conditions of 100 W and 100 mm/s, high-density (99.58%) Zn-Cu alloys with improved hardness (68.2HV) and yield strength (160 MPa) were achieved. These improvements are attributed to solid solution strengthening, segregation strengthening, and grain refinement. The Zn-Cu alloys also demonstrated favorable degradation behavior, with a rate of 0.16 mm/year. This degradation is primarily driven by micro-galvanic corrosion between the CuZn5 phase and Zn matrix, along with refined grains and increased grain boundary density. This work demonstrates a viable strategy for fabricating Zn-based implants with enhanced structural integrity and mechanical performance via LPBF.