Batteries & Supercaps最新文献

In all-solid-state batteries (ASSBs), the mechanical stress generated during electrode (de)lithiation plays a critical role in determining the cell longevity because of the induced degradation mechanisms. This stress originates from local volume fluctuations in the active electrode materials, such as nickel-rich LiNi_xMn_yCo_zO₂, which are intrinsically coupled to spatial variations in lithium-ion concentration during electrochemical cycling. Herein, a novel ASSB model that considers electrochemistry and solid mechanics in a one-way coupled manner is presented. The model spatially resolves 3D-microstructure of an ASSB half-cell generated from wet manufacturing process simulations and is based on linear continuum mechanics. The coupling of electrochemistry and solid mechanics is incorporated via lithiation-dependent volumetric changes of the active material and the microstructural changes due to deformed geometries affecting the particles percolation paths. Furthermore, it is shown that the overall volume change of the half-cell is dependent on the C-rate and on the applied stack pressure. Finally, the findings demonstrate that solid-mechanical effects and their interplay with electrochemical phenomena significantly impact the evolution of interfacial surface area and the total pore volume. These factors are crucial for ensuring accurate computational predictions, underscoring the necessity of incorporating such interactions in battery modeling approaches.

Pre-lithiation is an essential step in lithium-ion capacitors (LICs) due to the lack of Li⁺ in both electrodes. The integration of dilithium squarate (Li₂C₄O₄) into the positive electrode of LICs is considered one of the most promising pre-lithiation strategies. Therefore, the ability of Li₂C₄O₄ decomposition products to modify the solid electrolyte interphase has been recently disclosed, although their impact on the positive electrode surface has not been studied yet. In this work, the improvement of the electrochemical performance when Li₂C₄O₄ was included has been investigated by analyzing the surface of activated carbon-based electrodes with and without Li₂C₄O₄ by scanning electron microscopy and X-ray photoelectron spectroscopy. The decomposition of Li₂C₄O₄ leads to the formation of a surface layer on the positive electrode that remains unaltered regardless of the applied potential, as well as after an aging test. Thus, the improved electrochemical performance is attributed to the presence of a pseudocapacitive charge storage mechanism enabled by the surface layer. Lastly, the cells are modified to reveal the main components participating in the surface layer formation. These findings provide valuable insights into the impact, benefits, and limitations of Li₂C₄O₄, which will accelerate the development of other suitable alternative sacrificial salts.

Hydrogen-bonded organic frameworks (HOFs) have been increasingly applied in industrial fields owing to their low weight and high pore volume. In particular, HOFs incorporating redox-active units have emerged as promising electrode materials for energy storage devices alongside other porous organic polymers. This study explores the application of HOFs incorporating tetrathiafulvalene (TTF) derivatives that are well-known as molecular conductors with multielectron redox properties for rechargeable batteries. Specifically, the battery performance of HOFs-based TTF-tetrabenzoate (H₄TTFTB) as a cathode active material in lithium-ion (LIBs) and sodium-ion batteries (SIBs) is evaluated. H₄TTFTB-based HOFs demonstrate enhanced cycling stability, with a particularly large enhancement achieved in SIB systems, due to the inherent structural stability of HOFs. Additionally, driven by the synergistic redox activity of TTF and bipyridine units, TTF-hybrid-HOFs combining H₄TTFTB with redox-active bipyridine units exhibit improved battery capacities. These findings underscore the potential of H₄TTFTB-based HOFs, which combine excellent redox activity and mechanical stability, as promising candidates for high-performance energy storage devices, highlighting the advantages of integrating rigid heterocyclic compounds with redox-active functionalities into HOF structures for future battery applications.

The work proposes a novel and fast method to synthesize Ti₃C₂T_x MXene with enhanced redox activity and improved structural, optical, and electronic properties by incorporating NaOH in the late etching stage. The technique eliminates the need for postetching delamination while maintaining the properties of delaminated MXene. Optimizing the concentration of NaOH leads to the removal of the unetched MAX phase from MXene in the mild in situ HF etching technique. The obtained ultrapure MXene is used as the negative electrode in an asymmetric supercapacitor device configuration. The MXene//RuO₂ asymmetric device showed superior electrochemical performance with a specific capacitance of 73.3 F g⁻¹, energy density of 23 Wh kg⁻¹, and power density of 796 W kg⁻¹, with potential extendable up to 1.5 volts. The device retained more than 90% of its performance at the end of 2000 cycles. The all-solid-state asymmetric supercapacitor device fabricated using PVA/H₂SO₄ gel polymer as the electrolyte, and Na-MX and RuO₂ as the electrodes gave a specific capacitance of 845 mF g⁻¹, energy density of 470 mWh kg⁻¹, and power density of 5000 mW kg⁻¹ at a current density of 5 mA g⁻¹ with an extendable voltage window up to 2 V, more than twice the window obtained using symmetric supercapacitor with MXene as electrode.

The surging demand for electric vehicles and energy storage technologies drives an unprecedented accumulation of spent batteries, which leads to severe environmental burdens and critical resource wastage. Traditional recycling technologies rely on high-temperature calcination or acid/base leaching, and the final products in the form of alloys or salts can only be used as precursors. In contrast, advanced direct recycling regenerates spent cathode and anode into materials that can be directly used in battery production, simplifying the recycling process and improving economic benefits, which is expected to become a shortcut for lithium-ion battery recycling in the future. This review analyzes the state-of-the-art direct recycling methods based on the failure mechanisms for anodes and cathodes, divides them into solid-state recycling, hydrothermal repair, and others according to different recycling conditions, and summarizes separately the advancements and limitations of each method, to guide the scale-up and sustainability of recycling. Furthermore, this review systematically introduces artificial intelligence (AI) assisted direct recycling strategies, emphasizing the role of AI in optimizing the pretreatment and recycling processes. Finally, the practical challenges and future opportunities for direct recycling are discussed, providing important reference for further development.

To address the dual challenges of fragile structures prone to damage and packaging systems susceptible to leakage in thermal management of electronic devices for traditional phase change materials, this study proposes an organic-porous synergistic packaging strategy. A porous TiO₂ skeleton is in situ constructed via a one-pot one-step method to synchronously encapsulate paraffin wax and thermoplastic elastomer styrene ethylene butylene styrene (SEBS). The innovation lies in utilizing solvent evaporation-induced phase separation and sol–gel reaction to enable the porous TiO₂ (specific surface area 316.307 m²g^–1) and SEBS to form a rigid-flexible synergistic structure, achieving low leakage rate and stability in 2000 thermal cycles. In battery thermal management, the battery temperature is controlled within a safe range at 1–3C rates, extending the safe operation duration of the battery by more than 10 times. It provides a referable option for efficient thermal management of wearable electronic devices and flexible devices.

Lithium–oxygen (Li–O₂) batteries have attracted substantial interest due to their high theoretical specific energy and environmental benignity. However, their practical electrochemical performance remains hampered by sluggish cathode reaction kinetics, unstable solid electrolyte interphase (SEI) at electrode/electrolyte interfaces, and lithium dendrite growth. Addressing these system-wide challenges necessitates the development of novel functional materials as a pivotal strategy. Among explored materials, high-entropy alloys (HEAs) demonstrate significant advantages through finely tunable composition and electronic structure, enabling synergistic functionality that offers new pathways for enhancing the comprehensive performance of Li–O₂ batteries. This review outlines the fundamental reaction mechanisms and core challenges of Li–O₂ batteries, and then systematically examines recent advances in HEA applications across three critical domains: cathode catalyst design, electrolyte optimization, and anode protection. Finally, perspectives on future research directions for HEAs in Li–O₂ batteries are offered.

Despite the abundance of battery state estimation algorithms in the BMS literature, their applicability to emerging cell chemistries remains uncertain, as evaluating their performance across diverse use cases is complex, resource-intensive, and time-consuming. In this work, we introduce an evaluation framework designed to assess the performance of diagnostic algorithms across various applications and external conditions. Our framework relies on simulations of different operational scenarios grouped into categories and evaluates algorithm performance using statistical metrics that represent accuracy, bias, and precision. While our framework can be used for various state estimators and applications, we demonstrate its functionality by benchmarking three common and real-time capable State of Charge (SOC) algorithms across three cell types, including a sodium-ion battery. Within our case study, we show that the tested model-based algorithms offer excellent transferability for the specific sodium-ion battery considering different operation conditions. Additionally, we demonstrate that the characteristic OCV(SOC) relationship of the sodium-ion cell allows for the use of lower-quality and more affordable sensors, as the cell is less sensitive to measurement inaccuracies. Overall, our open-source framework supports the systematic assessment of diagnostic algorithm transferability and provides a foundation for informed decision-making when selecting algorithms for a specific application and cell type.

The push to use metallic lithium-based batteries motivates a shift toward the use of solid polymer electrolytes. To improve the ionic conductivity values of such electrolytes, liquid additives (plasticizers) are usually added. However, the improvement in conductivity comes at the expense of a deterioration of the anode–electrolyte interface, resulting in poorer electrochemical cell performance. In this study, the use of a polymer coating consisting of polyethylene oxide, LiTFSI, and LiNO₃ is proposed. The coating shows improved electrochemical performance and stability, delayed cell failure and a more uniform distribution of Li deposits. These improvements are attributed to the increased stability of the solid electrolyte interphase, which is confirmed by using a combination of electrochemical impedance spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. In contrast, it is found that the interphase in uncoated Li electrodes is likely affected by continuous reactions with the plasticizer, further confirming the need to use such protective coatings to achieve long-term operation in practical solid-state Li metal batteries.

Polysulfides formed in Li–S batteries pose various characteristics. For example, Li₂S is solid while Li₂S₄ is liquid. Li₂S is insoluble in battery electrolytes while Li₂S₄ is soluble. All of them are negative charge bearing molecules. Lithium polysulfides are Lewis acids. Herein, a binder with multiple interaction motifs is presented to confine the polysulfides in the cathode. The base of the binder is sodium salt of carboxy methyl cellulose (CMC). β-cyclodextrin (CD) that comprises 21 hydroxyl groups is used because they hydrogen bond with the carboxylate moieties of CMC to impart mechanical strength to the binder to accommodate volume change during the sulfur to polysulfide conversion. Indeed, it is found that the binder with CD shows improved mechanical properties compared to CMC. The cavity of the CD is used to prepare an inclusion complex with ferrocene methanol. Due to the presence of Fe²⁺, the batteries comprising the inclusion complex show improved electrocatalytic properties. The Li–S batteries deliver a specific capacity of 780 mA h g⁻¹ (1 C) at a high sulfur loading of 4.7 mg cm⁻² and lean electrolyte (E/S of 5 μL mg⁻¹).