Energy Storage Materials最新文献

Zirconium-based halide solid electrolyte, Li₂ZrCl₆, with low raw-material cost and high oxidative stability is a promising candidate for next-generation energy storage devices. However, the low ionic conductivity hinders its practical applicability. Herein, we report a new zirconium-based superionic conductor based on high-valence Ta⁵⁺ doping strategy. The optimized Li_1.7Zr_0.7Ta_0.3Cl₆ (LZTC) exhibits excellent ionic conductivity of 1.42 mS cm^-1 at 25 °C. Moreover, it can be further increased up to 1.68 mS cm^-1 with a low activation energy of 0.28 eV by slightly tuning Li⁺ concentration. In addition, LZTC possesses a big compact density of 2.67 g cm^-3 under 250 MPa and is compatible with 4V-class cathodes. Density function theory (DFT) and bond valence site energy (BVSE) calculations reveal Ta⁵⁺ substitution significantly reduces the migration energy barrier of lithium ions due to the distortions and defects of local structural environment. The assembled all-solid-state batteries with Li_1.7Zr_0.7Ta_0.3Cl₆ as electrolyte and scNCM811 as cathode show excellent cycling performance for 600 cycles at 1C with a high-capacity retention of 85.7%.

One of the most demanding goals in the field of Na-ion batteries is to find an appropriate anode material that delivers high capacities and can endure numerous cycles without structural degradation. Antimony stands out with a theoretical capacity of 660 mAh·g⁻¹ and relatively high electrical conductivity. However, its challenges are pulverization and degradation of its microstructure due to volume changes. In this work, we used a solvothermal reaction to synthesize the composite material Sb/Sb₄O₅Cl₂/C, which is made of Sb with branch-shaped morphology and Sb₄O₅Cl₂ with cuboids-shaped morphology. The mechanism of the (de)sodiation of the composite material was analyzed both through operando and ex-situ measurements: X-ray diffraction, Raman spectroscopy, X-ray absorption spectroscopy, scanning electron microscopy, dilatometry, and online electrochemical mass spectrometry. The results show great mechanical integrity of the electrode, ensured by a lot of space for volume changes in the branch-shaped microstructure, buffered expansion/contraction by the amorphous matrix (sodiated Sb₄O₅Cl₂), and high electronic conductivity, thanks to carbon. The microstructural features and the multistep (de)sodiation mechanism of the Sb/Sb₄O₅Cl₂/C composite result in excellent cycling stabilities.

Polymer-based solid-state electrolytes with excellent processability and flexibility are ideal candidates for commercialisation in lithium-metal batteries. However, the current polymer-based solid-state electrolytes still have many problems such as low ionic conductivity, limited Li⁺ transport number and high interfacial resistance with electrodes. To address the above challenges, a solid-state rigid polymer composite electrolyte with high ionic conductivity (2.8 mS cm⁻¹) has been prepared based on the rigid polymer poly(2, 2′-disulfonyl-4, 4′-benzidine terephthalamide) (PBDT). Locally aligned PBDT-EMImN(CN)₂ grains are interspersed with in-situ formed interconnected LiFSI to form the structure of the polymer composite electrolyte. The formation of defective LiFSI nanocrystals at grain boundaries inside the polymer electrolyte acts as additional conductive networks providing fast Li⁺ transportation (t_Li⁺ = 0.59). The flexible region in the electrolyte gives excellent interfacial impedance (32.5 Ω cm²) with Li-metal electrode. The Li||Li batteries can be stably cycled for over 1000 cycles at 1 mA cm⁻² (25 °C). The assembled Li||LiFePO₄ batteries exhibit excellent cycling and multiplication performance over a wide operating temperature (from −20 to 60 °C). Moreover, this electrolyte material exhibits compatibility with high-voltage cathode LiNi_0.6Mn_0.2Co_0.2O₂ batteries. This electrolyte and design strategy is expected to inspire the realization of all-weather practical solid-state lithium-metal batteries.

Solid electrolytes (SEs) offer promising avenues for improving both the energy density and safety of lithium-ion batteries (LIBs). However, the grain boundary resistance remains a significant hurdle that impact the performance of LIBs, particularly when utilizing SEs in powder form. In this study, we introduce a novel approach to reduce grain boundary resistance in Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP) via secondary crystallization induced by liquid electrolytes (LEs). By immersing nano-sized LATP powders in LiPF₆/carbonates LEs, rapid aggregation and recrystallization into bulk micrometer-sized particles occur within minutes under ambient conditions. This secondary crystallization process alters the Li distribution within LATP bulk phase, substantially reducing the grain boundary resistance and enhancing Li-ion diffusivity. Consequently, the assembled LATP-modified commercial LiNi_0.89Co_0.07Mn_0.04O₂ cathode using LiPF₆ electrolyte delivers a remarkable discharge capacity of 105.4 mAh g⁻¹ at 4C, significantly superior to the bare electrode (44.7 mAh g⁻¹). The recrystallized LATP enhances the transport properties and pathways of Li⁺ ions within the cathode material, especially at high current densities. Multinuclear and multi-dimensional solid-state NMR analysis reveal that active F⁻ ions released from the hydrolysis of LiPF₆ electrolytes act as mineralizing agent, facilitating rapid agglomeration and secondary growth of LATP grains. Our findings underscore the efficacy of secondary crystallization using LEs as a promising strategy for eliminating grain boundary resistance and facilitating fast Li-ion conduction of SEs, thereby advancing LIB performance.

Water-in-salt electrolytes (WiSEs) have emerged as the primary preference in the domain of aqueous-based supercapacitors, thanks to their wide electrochemical stability window (ESW > 1.23 V). Here, we have chemically synthesized a unique lettuce coral-like structure of tosylate doped-poly(3,4-ethylenedioxythiophene) (PEDOT-tos) and tested it for supercapacitor application in a 17 molal (m) NaClO₄ WiSE, achieving an ESW of 1.9 V. The energy and power densities (E_d and P_d) of our PEDOT-tos supercapacitor are as high as 14 Wh kg^-1 and 7210 W kg^-1, respectively, with over 80 % capacitance retention after 10,000 continuous Galvanostatic charge-discharge cycles. The NaClO₄ WiSE increases the E_d and P_d of PEDOT by several folds compared to traditional H₂SO₄ electrolyte. This work encourages the exploration of a suitable combination of a PEDOT-based composite material and WiSE for high-performance supercapacitors.

Solid-state sodium batteries (SSNBs) are considered as a promising alternative to organic liquid-based batteries due to their excellent safety, high energy density and cost-effectiveness. However, SSNBs suffer from undesirable interfacial contact between Na and solid-state electrolytes such as NASICON-type Na₃Zr₂Si₂PO₁₂ (NZSP), dendritic growth and dramatic volume changes during cycling, which hinder their development towards actual applications. Herein, dendrite-free composite-type Na/NZSP module with ultrafast built-in ionic conductive framework is designed to promote the Na diffusion kinetics, partially restrict the volume effect, and simultaneously improve the wettability towards NZSP. Thanks to the unique module with supersodiophilic property, the thus-made all-solid-state Na-symmetric cells offer a reduced area specific resistance by more than two orders of magnitudes (from 1774.0 Ω cm² for the pristine Na/NZSP to 14.1 Ω cm² for the composite-type Na/NZSP module) and endow an ultralong lifespan of 7800 h at room temperature. Moreover, a full SSNB coupling with the Na/NZSP module and Na₃V₂(PO₄)₃ cathode achieves extremely long and stable cycling of more than 5760 cycles at 1.0 C with 87.9 % of capacity retention and high-rate capability at 3.0 C, being among the best achievements reported so far. The findings open a new window of composite-type Na/NZSP module design for high-performance SSNBs.

Constructing structured anodes with lithiophilic materials has emerged as an essential strategy to stabilize Li deposition and accomplish highly reversible Li metal batteries (LMBs). Nevertheless, a lithiophilic material, which meets the requirements of low cost, excellent electronic conductivity and especially chemical stability, is still absent. Herein, we report the discovery of a new class of lithiophilic anti-perovskite nitrides MNNi₃ (M=Zn, Cu, In) that not only are cost-effective and highly conductive, but also possess excellent stability against Li metal. More specifically, electrochemical tests in combination with density functional theory (DFT) calculations reveal that the lithiophilicity of MNNi₃ arises from unique chemical/physical adsorption rather than the previously proposed alloying or conversion reaction mechanisms. The MNNi₃@CC enabled symmetric cells exhibit better rate capability and longer cycle life than the cells with pure carbon cloth and Ni₃N@CC. More importantly, the excellent electrochemical performances of MNNi₃ anodes are also verified by ZnNNi₃@CC in a LiFePO₄ coupled full cell with minimal capacity degradation of 28% in 1500 cycles under the charge/discharge current of 1C. Beyond offering a new type of non-reactive lithiophilic materials to outstanding achieve battery performance, this study deepens the understanding of the lithiophilic nature of different metal nitrides, which paves a way for developing highly reversible lithium metal anode.

Electrolyte additive is one of the most effective strategies to optimize Zn anode in aqueous zinc ion batteries. Few reports are available on the influence of spatial-hindrance effect on Zn²⁺ deposition behavior. Herein, the environmentally safe aspartame and neotame are selected to finely tune the molecular structure, thereby affecting molecular adsorption behavior as well as Zn²⁺ diffusion and deposition behavior, and the molecular structure regulation strategy is proposed to achieve the optimization of Zn anode. According to theoretical calculations and experimental conclusions, aspartame, as the molecular robot, uniformly adsorbs on Zn anode surface via oxygen-containing functional groups, captures Zn²⁺ via −NH₂, homogenizes Zn²⁺ flux, and catalyzes Zn²⁺ desolvation, resulting in Zn²⁺ oriented deposition to form Zn (100) facet texture. Benefited from the molecular structure regulation strategy, Zn anode exhibits an ultra-long lifespan of more than 4600 h and an extremely high cumulative plated capacity of 11.7 Ah cm⁻². Furthermore, Zn anode operates stably for more than 270 h under 80 % depth of discharge and possesses a high coulombic efficiency of 99.8 % in Zn||Cu half cells. This strategy provides a new perspective on selecting additives.

Nickel-rich layered oxide is a promising cathode material for the next generation lithium-ion batteries (LIBs) because of its high energy density and cost efficiency. Unfortunately, it suffers from unsatisfying electrochemical performance owing to intrinsic interfacial and structural instability, which limits its application at scale. In this work, a phase compatible TiBO₃ coating layer on single crystalline LiNi_0.83Co_0.11Mn_0.06O₂ (TBO-SC-NCM) is constructed via modified solid-state chemical reaction. The coating layer serves as a protective screen to mitigate the erosion of organic electrolyte towards TBO-SC-NCM. Furthermore, both titanium ions and boron ions successfully diffuse into the TBO-SC-NCM bulk phase during the annealing process, with titanium ions being uniformly distributed while boron ions accumulating close to the surface. The formation of strong Ti-O bond effectively inhibits the bulk phase structure degradation of TBO-SC-NCM. The near-surface enriched B-O bond greatly stabilizes the surface lattice oxygen at the deeply delithiated state. Additionally, the spread of layer spacing due to the doping of heterogeneous ions ensures the rapid diffusion of Li⁺, thus improving the rate performance of TBO-SC-NCM. As a h cathode materials.

Currently, the assembly of all-solid-state batteries (ASSBs) mostly involves powder pressing method, which is primarily suitable for laboratory research and presents challenges for industrial-scale manufacturing of ASSBs. Wet processes are the most mature scale-up film formation technology in the lithium-ion battery industry. Therefore, the development of wet processes for forming solid-state electrolytes (SSEs) films is of great interest for the industrial production of ASSBs. Understanding the solvent stability of SSEs is a prerequisite for realizing the industrial production of ASSBs using wet processes. Halide SSEs have attracted extensively attention due to their mechanical flexibility, superionic conductivity, and wide electrochemical window. However, to date, the stability of halide SSEs and solvents has not been systematically investigated. Herein, we systematically investigate the changes in the solubility, structure, and ionic conductivity of halide SSEs upon exposure to different solvents, providing a crucial technical foundation for the wet processing of ASSBs.