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In this study, a novel concept of multipoint anionic bridge (MAB) is proposed and proved, which utilizes anions with different sites to connect with the asymmetric solvation structure (ASS). Compared to usual solvation structures, this study utilizes the multifunctional groups of difluoro(oxalate)borate anion (ODFB−), which can connect with Li+. By tailoring the concentration, the anion serves as a bridge between different solvated structures. The electrolyte is investigated through in situ techniques and simulations to draw correlations between different solvation structures and reaction pathways. The proposed design demonstrates remarkable high‐temperature performance on both the anode and cathode sides, enabling stable cycling of LCO||graphite (0.5 Ah, 1.0 C) pouch cell for over 200 cycles at 80 °C and facilitating Li||MCMB and Li||LFP cells to deliver stable performance for 200 cycles at 100 °C. This work paves the way for the development of high‐performance electrolyte systems by designing and using new multipoint anions to construct ASSs. [ABSTRACT FROM AUTHOR]

With the rapid development of new energy vehicles and energy storage industries, the demand for lithium-ion batteries has surged, and the number of spent LIBs has also increased. Therefore, a new method for lithium selective extraction from spent lithium-ion battery cathode materials is proposed, aiming at more efficient recovery of valuable metals. The acid + oxidant leaching system was proposed for spent ternary positive electrode materials, which can achieve the selective and efficient extraction of lithium. In this study, 0.1 mol L−1 H2SO4 and 0.2 mol L−1 (NH4)2S2O8 were used as leaching acid and oxidant. The leaching efficiencies of Li, Ni, Co, and Mn were 98.7, 30, 3.5, and 0.1%, respectively. The lithium solution was obtained by adjusting the pH of the solution. Thermodynamic and kinetic studies of the lithium leaching process revealed that the apparent activation energy of the lithium leaching process is 46 kJ mol−1 and the rate step is the chemical reaction process. The leaching residue can be used as a ternary precursor to prepare regenerated positive electrode materials by solid-phase sintering. Electrochemical tests of the regenerated material proved that the material has good electrochemical properties. The highest discharge capacity exceeds 150 mAh g−1 at 0.2 C, and the capacity retention rate after 100 cycles exceeds 90%. The proposed new method can extract lithium from the ternary material with high selectivity and high efficiency, reducing its loss in the lengthy process. Lithium replenishment of the delithiation material can also restore its activity and realize the comprehensive utilization of elements such as nickel, cobalt, and manganese. The method combines the lithium recovery process and the material preparation process, simplifying the process and saving costs, thus providing new ideas for future method development. [ABSTRACT FROM AUTHOR]

The compatibility of lithium metal with organic solvents is the most crucial for lithium metal batteries (LMBs). Even though ether solvents show excellent compatibility toward lithium metal, the reactivity of the ether solvents at elevated temperatures and high voltages hinders their utilization in lithium metal battery systems. In this study, a high‐temperature ether electrolyte is designed comprising lithium oxalyldifluoroborate (LiODFB), diethylene glycol dibutyl ether (DGDE), 3‐methoxypropionitrile (MPN), and fluorinated ethylene carbonate (FEC), which is abbreviated as MDF electrolyte. The presence of MPN in the electrolyte changes the solvation structure, thereby facilitating increased redox reactions of ODFB− and synergizing with FEC to build a robust solid electrolyte interface (SEI), effectively inhibiting lithium dendrites growth and solvent decomposition. Consequently, the MDF electrolyte exhibits not only long cyclic stability and high coulombic efficiency in Li||Cu and Li||Li cells but also excellent cyclic characteristics in both Li||LiFePO4 (LFP) and Li||LiNi0.8Co0.1Mn0.1O2 (NCM811) cells. Remarkably, these cells demonstrate stable operation even when exposed to higher temperatures of up to 80 °C, while the Li||NCM811 cell maintains consistent cyclic stability at an elevated voltage level of 4.5 V. [ABSTRACT FROM AUTHOR]

Titanium dioxide of bronze phase (TiO2(B)) has attracted considerable attention as a promising alternative lithium/sodium‐ion battery anode due to its excellent operation safety, good reversible capacity, and environmental friendliness. However, several intrinsic critical drawbacks, including moderate electrochemical kinetics and unsatisfactory long cyclic stability, significantly limit its practical applications. It is crucial to develop reliable strategies to resolve these issues to advance the TiO2(B) based materials into practical applications in lithium/sodium‐ion batteries. In this review, both the theoretical and experimental investigations on the TiO2(B) based materials over the last few decades are chronically elaborated. Insights on the general and detailed evolution trends of the research on TiO2(B) anodes are provided. The review also points to future directions for the TiO2(B) anode research to advance the practical application of TiO2(B) anodes. [ABSTRACT FROM AUTHOR]

Abstract: Several series of Li1±x Mn2−y O4±δ and Li1.05Al y Mn1.95−y O4±δ samples with different oxygen defect degree have been synthesized by controlling synthesis temperature and procedures. The cycle performance of spinel as cathode in lithium batteries has been correlated with oxygen deficiency. The structure change of spinel during charge has also been investigated with respect with oxygen deficiency. [Copyright &y& Elsevier]

Abstract Metallic lithium, with super high theoretical specific capacity, enjoys great potential as an anode for rechargeable batteries. However, safety issues caused by lithium dendrite growth as well as limited cycling life restrict its practical application. Herein we validate that the application of a new dual-salt electrolyte composed of Lithium difluorophosphate (LiPO 2 F 2) and lithium bis(fluorosulfony)imide (LiFSI) in the same proportion enables the improved long-term cycling performance along with high coulombic efficiency for lithium metal batteries. With 1 M LiPO 2 F 2 and 1 M LiFSI in 1,2-dimethoxyethane as the electrolyte, a Li/Cu cell can be cycled at 1 mA for more than 300 cycles with a deposited capacity of 1.0 mAh. It also displays that a homogeneous and dendrite free solid electrolyte interphase layer is generated on the Cu electrode, which can be ascribed to the favorable stability of LiPO 2 F 2 and high ionic conductivity of LiFSI. These results deliver perceptions for the advancement of high-performance lithium metal anode. Highlights • A dual-salt electrolyte composed of LiPO 2 F 2 and LiFSI is proposed for LMBs. • The electrolyte shows high ionic conductivity and wide electrochemical windows. • Improved cyclic stability and high coulombic efficiency have been achieved. • Low voltage polarization and dendrite-free SEI layer have been observed. [ABSTRACT FROM AUTHOR]

Pre-lithiation technology is essential to improve the initial coulombic efficiency (ICE) and cycling stability of high SiO x content cells. Different amounts of pre-lithiation significantly affect the electrochemical performance of cells. In this study, three groups of LiNi 0.8 Co 0.1 Mn 0.1 O 2 || SiO x /Graphite pouch cells (SiO x , 45 wt%) with different pre-lithiation amounts are fabricated using an electrochemical pre-lithium method. The effects of pre-lithiation amounts on the capacity and cycling stability are comprehensively investigated by non-destructive tests and post-mortem analysis. The results show that increasing the amounts of pre-lithiation can substantially improve the capacity of the cells, but may also accelerate their aging. Further studies reveal that the cycling stability of SiOx/Graphite anode is strongly affected by the amounts of pre-lithiation, whereas the effect on the cathode is negligible. Moreover, titration gas chromatography (TGC) experiments are used to quantify the lithium loss in SiO x /Graphite anode. The accelerated formation of SEI and trapped lithiated active materials as well as lithium dendrites caused by over-lithiation at SiO x /Graphite anode are responsible for the rapid degradation of pouch cells with high pre-lithiation amounts. This work demonstrates the complex relationship between pre-lithiation amounts and electrochemical performance, which needs to be carefully measured in SiO x -based cells. [Display omitted] • NCM811||SiO x /Graphite pouch cells with different pre-lithiation amounts are evaluated. • Both ICE and cycle stability is greatly influenced by the pre-lithiation amount. • The amounts of pre-lithiation have little effect on the aging of the cathode. • High pre-lithiation amounts can accelerate anode aging. • Titration gas chromatography is used to quantify the lithium loss in anode. [ABSTRACT FROM AUTHOR]

Lithium secondary battery with a wide working temperature range is crucial to boost its increasing applications in harsh circumstances. Suppressing excessive electrolyte decomposition at high temperatures while maintaining reasonable electrochemical kinetics at low temperatures is critical for wide-temperature electrochemical performance. Construction of high temperature stable electrode-electrolyte interface layer by electrolyte formulation is an effective strategy to prevent electrolyte from uncontrollable decomposition. On the contrary to conventional thinking, propylene carbonate (PC) bearing poor filming ability to suppress electrolyte decomposition is used in this work to promote decomposition of the single lithium difluoro(oxalate)borate (LiODFB) salt in the electrolyte, producing inorganic-rich interface layer with good structure stability over a wide temperature range. Glutaronitrile (GLN) is further utilized to minimize the decomposition of PC by expelling PC out of the solvation sheath of lithium-ion. The teamwork of LiODFB, PC, and GLN makes a synergistic contribution to building a high-temperature stable electrode-electrolyte interface layer at both LFP and MCMB electrodes. Based on the approach developed in this work, the temperature window is successfully expanded to the range of from -40 °C to 140 °C. Excellent electrochemical performance is exhibited by both LFP/Li and MCMB/Li cells from -20 °C to 100 °C in terms of reversible capacity and cyclic stability. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Li1+x Ni1/6Co1/6Mn4/6O2.25+x/2 (0.1≤ x ≤0.7) cathode materials have been synthesized by a simple carbonate co-precipitation method. The effects of the lithium content on the structure, physical property, and electrochemical performance of the samples have been investigated. As the increase of lithium content, the Li1+x Ni1/6Co1/6Mn4/6O2.25+x/2 evolves from a mixture of hexagonal R−3m, monoclinic C2/m, and spinel Fd−3m structure to a mixture of hexagonal and monoclinic structure, accompanied with less cation mixing between Li+ and Ni2+. The increase of x value also affects the size of the primary particles and the roughness of the secondary particles. The Li1+x Ni1/6Co1/6Mn4/6O2.25+x/2 with appropriate lithium content, e.g., x =0.3, thereby small particle size, high pellet density, and low cation mixing, brings on the largest discharge capacity, which is more than 288mAhg−1 in the voltage range of 2.0–4.8V at 25mAg−1, and the lowest irreversible capacity loss of 47mAhg−1 among these cathode materials. [Copyright &y& Elsevier]