Energy Storage Materials最新文献

Conventional metallurgical technologies for recycling cathode materials from retired Li-ion batteries goes against carbon neutrality owing to massive material input and energy consumption. Although featuring with simplified process, direct regeneration technology still fails to bypass high-temperature driving forces for Li⁺ compensation of degraded cathodes. Herein, chemical re-lithiation strategy mediated by ferrocene is proposed to directly regenerate the Li-deficient spent cathodes. Ferrocene and its derivatives, the so-called p-type redox mediators, can be oxidized spontaneously from neutral molecules to stable cations under ambient conditions, allowing them to function as electron donors. Meanwhile, lithium salts serve as Li⁺ donors to ensure charge neutrality of the cathode lattice. The effects of solvation and substituent are thoroughly investigated to precisely regulate the potential of a series of ferrocene-based reductants. Chemical re-lithiation is driven thermodynamically by the intrinsic potential gap between ferrocene and degraded cathodes, thus fundamentally realizing a rapid lithiation reaction (taking less than 20 minutes at 25°C), while avoiding the involvement of high-temperature operation. Diverse characterizations have been performed to explored the Li⁺-electron concerted re-lithiation mechanism. The regenerated LiFePO₄ cathode demonstrated comparable Li⁺ storage capability to commercial cathode. Life-cycle analysis verifies the economical and environmental superiority of our chemical re-lithiation strategy to metallurgy in practical industry. The thermodynamically spontaneous chemical re-lithiation provides competitive options for greener recycling of retired batteries in the future.

The exceptional electrochemical oxidative stabilities of halide solid electrolytes (SEs) have led to extensive research on Li and Na all-solid-state batteries. In this study, we report a new K⁺ SE, cubic KTaCl₆, with a remarkable K⁺ conductivity of 1.0 × 10⁻⁵ S cm⁻¹, synthesized via a mechanochemical method. This value represents a 1000-fold enhancement over that of samples prepared through heat treatment, which is remarkable among halide K⁺ SEs reported to date. Through structural characterization via X-ray diffraction, Rietveld analysis, and bond valence energy landscape calculations, we reveal three-dimensional K⁺ migration pathways facilitated by face-sharing KCl₁₂¹¹⁻ cuboctahedra. This configuration is in contrast to that of the monoclinic KTaCl₆ produced through annealing, which features discontinuous K⁺ migration pathways. These pathways are formed by the edge- or corner-sharing of KCl₁₂¹¹⁻ anti-cuboctahedra, resulting in a significantly reduced K⁺ conductivity. Cyclic voltammetry measurements employing three-electrode cells indicate high electrochemical stability up to ≈3.7 V (vs. K/K⁺).

Direct regeneration, as the main recycling manner, displays the short-process and high economic value, which has been devoted to considerable attentions. Limited by the existed pre-treatments, there are still some Al-impurities of spent material, resulting in the unstable electrochemical properties of regenerated material, meanwhile the excessive removal of Al-impurities brings the risk of regeneration cost. Thus, exploring the threshold reference of Al-impurities is urgent for regeneration of spent materials. Herein, through the introduction of Al₂O₃ with different content, spent LiCoO₂ were successfully regenerated, displaying the evolution of physical-chemical properties. With suitable Al adding (0.02 wt.%), the broadening layer distance and storage space are found. As a cathode, the as-optimized sample shows a capacity of 172.7 mAh g⁻¹ at 0.2 C, and the capacity retention was 84% after 500 cycles at 5.0 C, even better than Al-impurity-free regenerated sample. Supported by the detailed kinetic analysis, it could be deduced that, suitable Al-introduction is beneficial for the fast insertion/extraction of ions, meanwhile too excess adding could bring about the blocking of diffusion paths and by-production surface stacking. Given this, this work is expected to shed light on the physical-chemical effect of Al-impurities, meanwhile offering the threshold reference for Al-doping content in practical regenerated industry.

Dielectric capacitors, characterized by ultra-high power densities, have been widely used in Internet of Everything terminals and vigorously developed to improve their energy storage performance for the goal of carbon neutrality. With the boom of machine learning (ML) methodologies, Artificial Intelligence (AI) has been deeply integrated into the research and development of dielectric capacitors, including predicting material properties, optimizing material composition and structure, augmenting theoretical knowledge and so on. Through typical application cases, we comprehensively review that AI has greatly broadened the scope of the design and discovery of dielectric capacitors at multiple scales, ranging from atoms/molecules to domains/grains, films/bulks, and devices/systems. Finally, an outlook on potential solutions to current challenges and some novel applications and breakthroughs that AI may facilitate in the field of dielectric capacitors are highlighted.

All-solid-state batteries (ASSBs) have attracted considerable attention due to their high stability, offering a safer alternative to currently used batteries. Extensive research has been conducted to improve cathode part performance. However, the conventional hand mixing (HM) process results in inhomogeneous particle distribution, causing poor interparticle contact due to uneven stress distribution, and the solution process causes unwanted solid electrolyte (SE) deterioration when using a polar solvent although it ensures uniform SE distribution. To overcome these limitations, based on the design rule considering SE surface coverage of less than 100 %, we propose a cathode/SE composite, showing decent ionic/electronic conductivities, uniform SE distribution, and intimate interparticle contact, achievable through a mass-producible mechanical mixing (MM) process. Unlike the HM cell, the MM cell forms well-defined ionic percolating pathways and shows excellent structural stability. Consequently, the MM cell exhibits improved capacity retention during 1000 cycles and stable cyclability even under the harsh condition of 7 wt% SE. Finite element analysis theoretically demonstrates that uniform electrode and electrolyte currents are responsible for the improved performances including increased cathode utilization efficiency and reduced overpotentials. This study reveals the importance of composite design and uniform SE distribution in developing high-performance ASSBs at a practical cell level.

Achieving consecutive flattening and dendrite-free deposition for the zinc anodes is essential to avoid internal short circuits or premature failure in the Zn-ion hybrid supercapacitor (ZHSC), which largely depends on the crystal growth during the electrocrystallization process. Herein, tetrapropyl ammonium bromide additives were employed to reconstruct the inner Helmholtz plane (IHP) structure for manipulating the Zn deposition behavior and stabilizing the interfacial electrochemistry. Joint experimental and theoretical results show that electrophilic quaternary ammonium cations (TPA⁺) provoke the linkage effect after the specifical adsorption at IHP of the Zn electrode, which includes the molecular/ion distribution regulation, electrostatic shielding effect, crystallographic optimization, and solid electrolyte interphase (SEI) layer formation. The adsorbed TPA⁺ cations at IHP expel SO₄²⁻ anions, bringing a reconfiguration of the ion/molecule distribution, which leads to a relatively uniform Zn²⁺ ions distribution at electrode/electrolyte interface and a sluggish electroreduction reaction kinetics. Meanwhile, the electrostatic shielding effect regulates the crystallographic energetic preference of Zn deposits and induces the stratiform Zn growth and dominant Zn (002) texture. Concomitantly, the partial interfacial adsorbed TPA⁺ cations was electrochemically reduced to form the inorganic-organic hybrid SEI layer to further enhance the corrosion resistance and stability of the Zn electrode. Consequently, TPA⁺ cations mediated electrolyte enables Zn||Zn cells to exhibit a reversible plating/stripping performance for more than 2800 h. Additionally, a long-term cycling life can be obtained in the Zn||activated carbon ZHSC with this electrolyte. The electrolyte mediation strategy to realize the complementary interface effect and crystalline optimization provides promising feasibility on highly reversible Zn anodes.

The hydrogen evolution reaction is the most prominent parasitic reaction for aqueous battery chemistries. Although water-in-salt electrolytes show greatly enhanced electrochemical stability, increasing the voltage of aqueous batteries further by lowering the potential of the negative electrode remains a major challenges due to reductive water splitting. Here, we systematically investigate twelve niobium-based anode materials that show much lower activity towards hydrogen evolution reaction than classic titanium-based anode materials such as lithium titanate (Li₄Ti₅O₁₂) or titanium dioxide and are therefore a much better choice for aqueous batteries_. We confirm Zn₂Nb₃₄O₈₇ to be the most suitable anode materials for aqueous batteries among these niobates and present full cell cycling data with LiMn₂O₄ and LiNi_0.8Mn_0.1Co_0.1O₂ cathodes in a water-in-salt/ionic liquid hybrid electrolyte. Furthermore, we compare the catalytic activities of Zn₂Nb₃₄O₈₇ and Cu₂Nb₃₄O₈₇, with the latter being incompatible with aqueous batteries, and discuss the origin of the large difference in activity toward hydrogen evolution reaction.

Although O3-type layered oxides have become viable cathode materials for sodium-ion batteries (SIBs) due to their high energy densities, they still suffer from narrow ion channels and serious structure degradation, severely jeopardizing their electrochemical properties. Here, a stable O3-type layered oxide NaNi_0.4Mn_0.4M_0.2O₂ (M= Fe, Cu, Mg, Ti, Sn) (HE-NaNM) was synthesized by a high-entropy doping strategy. Owing to the introduction of the metal cations with ionic radiuses in a range of 0.61-0.73 Å into the layered structure, the lattice is expanded from 15.94 to 16.03 Å in c-axis, associated with a high distortion of TMO₆ octahedrons, offering broad channels for sodium-ion transport in the lattices. Moreover, such expanded lattices and highly distorted TMO₆ octahedrons enable to efficiently restrain the migration of TM ions and the severe sliding of TMO₂ slabs, affording one-step reversible structure evolution between O3 and P3 phase during sodium extraction/insertion without formation of harmful interphases. As a result, a good rate capability of 77.9 mAh g^-1 at 10 C and a long-term cycling stability up to 400 cycles at 5 C are achieved for sodium storage.

Owing to their enhanced safety and potentially high energy density, all-solid-state batteries (ASSBs) are gaining discernible attention in the emerging era of electric mobility. However, maintaining the physical contact between the solid components of ASSBs during repeated charging and discharging cycles is a formidable challenge, particularly when the cell constituents undergo large volume changes. High stack pressure is often required to compensate for this volume change and tighten the interparticle contact, but elevation of the pressure beyond the range that is commercially adoptable (typically below 1 MPa) would render the entire technology impractical for vehicular applications. To overcome this technical hurdle, a variety of strategies has been developed in the battery community at both the material and cell levels. This paper comprehensively summarizes the effect of volume change on the performance of ASSBs and highlights recent studies that offer solutions to circumvent the relevant issues. Additionally, we propose strategic approaches for addressing the drawbacks related to the volume change of cell components toward realizing highly reliable ASSBs operating under low stack pressure.