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Anion-intercalation lithium metal batteries (AILMBs) are appealing due to their low cost and fast intercalation/de-intercalation kinetics of graphite cathodes. However, the safety and cycliability of existing AILMBs are constrained by the scarcity of compatible electrolytes. Herein, we showcase that a difluoroester can be applied as electrolyte solvent to realize high-performance AILMBs, which not only endows high oxidation resistance, but also efficiently tunes the solvation shell to enable highly reversible and kinetically fast cathode reaction beyond the trifluoro counterpart. The difluoroester-based electrolyte demonstrates nonflammability, high ionic conductivity, and electrochemical stability, along with excellent electrode compatibility. The Li| |graphite AILMBs reach a high durability of 10000 cycles with only a 0.00128% capacity loss per cycle under fast-cycling of 1 A g−1, and retain ~63% of room-temperature capacity when discharging at −65 °C, meanwhile supply stable power output under deformation and overcharge conditions. The electrolyte design paves a promising path toward fast-rate, low-temperature, durable, and safe AILMBs. The authors report a difluoroester electrolyte to enhance anion intercalation lithium metal batteries (AILMBs), improving safety and cyclability. This enables cost-effective graphitic carbon cathodes, with high durability, stability, and performance. [ABSTRACT FROM AUTHOR]

Silicon monoxide (SiO) is a promising anode material for Li-ion batteries because of its high capacity. Though, its low first Coulombic efficiency (FCE) due to the formation of inactive Li–Si–O compounds during lithiation hinders its practical application. Herein, we report a facile pre-sodiation technique by annealing SiO with a small amount of Na 2 CO 3 (≤ 5 wt%) under 850 °C, which improves FCE of pristine SiO from 61.4% to 86.0% without the use of lithium metal, solvent and disassembling and re-assembling of cells. Transmission electron microscopy, X-ray photoelectron spectroscopy, and nuclear magnetic resonance demonstrate that the incorporation of Na facilitates the disproportionation of SiO into crystalline Si and SiO 2 through nucleophilic substitution, and reduces the reactivity of the oxygen atoms with lithium and thereby suppresses the irreversible capacity during initial lithiation. The pre-sodiation process also improves thermal stability of SiO. Since the Na-containing SiO material is not sensitive to moisture in ambient condition, special handling of the material is not necessary. Combining with a LiFePO 4 cathode, the full cell shows a FCE of 85.8% with good cycle stability. The energy density of lithium-ion battery can even reach 900 Wh L−1 based on a theoretical calculation with high-capacity Ni-based metal-oxide cathode. • First Coulombic efficiency of SiO is increased to 86% by heat-treating with Na 2 CO 3. • Na 2 CO 3 facilitates disproportionation of SiO to SiO 2 , inactivating the oxygen atoms in the lattice. • Thermal stability of pre-treated SiO is enhanced with less heat generation. • The treated material is stable in air and exhibits remarkable water compatibility. • A LIB with volumetric energy density of 900 Wh L−1 can be achieved with optimization. [ABSTRACT FROM AUTHOR]

Metal chalcogenides undergoing alloying and conversion mechanism can give high capacity as anode for lithium-ion batteries. However, large volume change and phase segregation lead to poor cycle performance. In this study, we focus on Sb 2 Se 3 and develop methods to enhance its long-term stability and reversibility. In particular, we find that carbon encapsulation reduces volume change during lithiation/delithiation and facilitates the recombination process of Sb and Se even after long cycling. With an addition of 20 wt% acetylene black, the Sb 2 Se 3 /C nanocomposite material exhibits an excellent cycle performance with a charge capacity of 545 mAh g−1 at 250 mA g−1 after 1000 cycles, corresponding to a capacity retention of 99.3%. We also demonstrate a full cell with LiFePO 4 cathode and Sb 2 Se 3 /C anode that is capable of delivering a stable capacity of 340 mAh g−1 at 1 A g−1 (about 3 C rate) after 300 cycles. • Sb 2 Se 3 nanoparticles encapsulated with carbon matrix is synthesized via mechanical ball-milling. • Carbon matrix enhances the mechanical stability of the electrode and suppresses phase segregation. • Sb 2 Se 3 @20%AB delivers a stable capacity of 545 mAh g−1 over 1000 cycles. • Sb 2 Se 3 @20%AB/LiFeO 4 full cell shows good rate capability and cycle stability. [ABSTRACT FROM AUTHOR]

High-Ni materials LiNiO 2 or LiNi 1-x M x O 2 (x < 0.1), whose energy density is over 800 Wh kg−1 (discharge capacity >220 mAh g−1, average discharge voltage ∼3.8 V), are promising candidates as cathode for next-generation electric vehicle batteries. However, commercial applications of high-Ni cathodes have been hindered by their fast capacity fading with cycling. Herein, we synthesized a series of high-Ni materials (LiNiO 2 , LiNi 0.95 Co 0.05 O 2 and LiNi 0.9 Co 0.1 O 2) by adopting nanosheet hydroxide precursors. The obtained high-Ni materials with micro-spheres made up of nanorod grains can sustain the large volume deformation and eliminates cracking during charge-discharge. Owing to the hierarchical structure, our as-synthesized high-Ni cathodes exhibit excellent cycling stability up to 4.7 V and under high temperatures, and the corresponding full cells show superior long cycling stability suitable for practical applications, such as 94% and 83% capacity retention after 300 and 500 cycles, respectively for a LiNi 0.95 Co 0.05 O 2 ||graphite cell. Overall, this study offers a facile approach to address the poor cycling stability of high-Ni materials. Nanosizing the primary crystals of high-Ni cathode materials (LiNi 1-x M x O 2 , x < 0.1) can eliminate particle pulverization, and nanorods are more effective than ultra-fine nanocrystals in suppressing cracking. The nanorods in pure or Co-doped LiNiO 2 can be directly synthesized from nanosheet hydroxide precursors. [Display omitted] • High Ni nanosheet hydroxide precursors were synthesized. • Corresponding LiNiO 2 and LiNi 0.95 Co 0.05 O 2 adopt spherical particles with nanorods. • Nanorods LiNiO 2 and LiNi 0.95 Co 0.05 O 2 cathodes exhibit excellent cycle stability. • Cycle stability maintained at high voltage and high temperature. • Nanorod grains accommodate lattice stress and suppress particle cracking. [ABSTRACT FROM AUTHOR]

Dual-ion battery (DIB) can potentially provide higher power, lower cost and faster charging capability than traditional lithium-ion batteries. Even though graphite can effectively accommodate anions as a cathode for DIB, the high working voltage of around 5 V vs. Li/Li+ leads to continuous side reactions, yielding to low Coulombic efficiency (CE < 90%) and poor cycle life. Here, we demonstrate that fluoroethylene carbonate (FEC) additive can induce a protective cathode electrolyte interface (CEI) on the graphite cathode, effectively suppressing electrolyte decomposition and stabilizing the graphite surface. This CEI enables a high CE (~99.0%) and an excellent cycle stability of 5000 cycles with capacity retention of 85.1% at the cutoff voltage of 5.1 V. The CEI layer can also reduce the self-discharge of the battery. Furthermore, the DIB exhibits a high-rate capability with 93.3% utilization at 30C (3000 mA g−1), enabling an ultrafast charging time within two minutes. This work sheds light on the features of CEI on graphite cathodes and provides a facile and economically effective strategy to achieve highly reversible/stable cycling of DIBs with high power capability. Image 1 • A protective cathode electrolyte interface is constructed on the graphite cathode. • The graphite surface is effectively stabilized for PF 6 − de-/intercalation process. • The cathode electrolyte interface significantly suppresses electrolyte decomposition. • The graphite-based dual-ion batteries with FEC additive exhibits low self-discharge. • Highly reversible/stable cycling and ultrahigh power capability are achieved. [ABSTRACT FROM AUTHOR]