Xiuquan Zhou

Bio: Xiuquan Zhou is an academic researcher from Argonne National Laboratory. The author has contributed to research in topics: Magnetic susceptibility & Electrolyte. The author has an hindex of 20, co-authored 41 publications receiving 1314 citations. Previous affiliations of Xiuquan Zhou include University of Maryland, College Park & University of Toledo.

All-temperature batteries enabled by fluorinated electrolytes with non-polar solvents

Abstract: Carbonate electrolytes are commonly used in commercial non-aqueous Li-ion batteries. However, the high affinity between the solvents and the ions and high flammability of the carbonate electrolytes limits the battery operation temperature window to −20 to + 50 °C and the voltage window to 0.0 to 4.3 V. Here, we tame the affinity between solvents and Li ions by dissolving fluorinated electrolytes into highly fluorinated non-polar solvents. In addition to their non-flammable characteristic, our electrolytes enable high electrochemical stability in a wide voltage window of 0.0 to 5.6 V, and high ionic conductivities in a wide temperature range from −125 to + 70 °C. We show that between −95 and + 70 °C, the electrolytes enable LiNi0.8Co0.15Al0.05O2 cathodes to achieve high Coulombic efficiencies of >99.9%, and the aggressive Li anodes and the high-voltage (5.4 V) LiCoMnO4 to achieve Coulombic efficiencies of >99.4% and 99%, respectively. Even at −85 °C, the LiNi0.8Co0.15Al0.05O2 || Li battery can still deliver ~50% of its room-temperature capacity. Batteries generally do not perform well at extreme temperatures, and electrolytes are mainly to blame. Here, the authors dissolve fluorinated electrolytes in highly fluorinated non-polar solvents, enabling batteries that can operate at a wide temperature range (−125 to +70 °C).

Intercalation of Bi nanoparticles into graphite results in an ultra-fast and ultra-stable anode material for sodium-ion batteries

Abstract: Sodium ion batteries (SIBs) have been revived as important alternative energy storage devices for large-scale energy storage, which requires SIBs to have a long cycling life and high power density. However, the scarcity of suitable anode materials hinders their application. Herein, we report a bismuth intercalated graphite (Bi@Graphite) anode material, which is substantially different from the previously reported metal@Graphene. In Bi@Graphite, the Bi nanoparticles between graphite interlayers enhance the capacity, while the graphite sheath provides a robust fast electronic connection for long cycling stability. The Bi@Graphite possesses a safe average storage potential of approximately 0.5 V vs. Na/Na+, delivers a capacity of ∼160 mA h g−1 at 1C (160 mA g−1), exhibits outstanding cycling stability (ca. 90% capacity retention for 10 000 cycles at 20C), and can maintain 70% capacity at 300C (∼110 mA h g−1 at 48 A g−1), which is equivalent to full charge/discharge in 12 s. Bi@Graphite demonstrates the highest rate-capability ever reported among all anodes for SIBs. Detailed characterization results indicate that the unique Bi nanoparticle-in-graphite structure and the fast kinetics of ether co-intercalation into graphite are responsible for these significant improvements, which could translate into SIBs with excellent power densities.

Self-Templated Formation of P2-type K0.6CoO2 Microspheres for High Reversible Potassium-Ion Batteries.

Abstract: Layered metal oxides have been widely used as the best cathode materials for commercial lithium-ion batteries and are being intensively explored for sodium-ion batteries. However, their application to potassium-ion batteries (PIBs) is hampered because of the poor cycling stability and low rate capability due to the larger ionic size of K+ than of Li+ or Na+. Herein, a facile self-templated strategy was used to synthesize unique P2-type K0.6CoO2 microspheres that consist of aggregated primary nanoplates as PIB cathodes. The unique K0.6CoO2 microspheres with aggregated structure significantly enhanced the kinetics of the K+ intercalation/deintercation and also minimized the parasitic reactions between the electrolyte and K0.6CoO2. The P2-K0.6CoO2 microspheres demonstrated a high reversible capacity of 82 mAh g–1 at 10 mA g–1, high rate capability of 65 mAh g–1 at 100 mA g–1, and long cycle life (87% capacity retention over 300 cycles). The high reversibility of the P2-K0.6CoO2 full cell paired with a hard c...

Fast parallel algorithms for short-range molecular dynamics

Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

Phd by thesis

Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Designing solid-state electrolytes for safe, energy-dense batteries

Abstract: Solid-state electrolytes (SSEs) have emerged as high-priority materials for safe, energy-dense and reversible storage of electrochemical energy in batteries. In this Review, we assess recent progress in the design, synthesis and analysis of SSEs, and identify key failure modes, performance limitations and design concepts for creating SSEs to meet requirements for practical applications. We provide an overview of the development and characteristics of SSEs, followed by analysis of ion transport in the bulk and at interfaces based on different single-valent (Li+, Na+, K+) and multivalent (Mg2+, Zn2+, Ca2+, Al3+) cation carriers of contemporary interest. We analyse the progress in overcoming issues associated with the poor ionic conductivity and high interfacial resistance of inorganic SSEs and the poor oxidative stability and cation transference numbers of polymer SSEs. Perspectives are provided on the design requirements for future generations of SSEs, with a focus on the chemical, geometric, mechanical, electrochemical and interfacial transport features required to accelerate progress towards practical solid-state batteries in which metals are paired with energetic cathode chemistries, including Ni-rich and Li-rich intercalating materials, sustainable organic materials, S8, O2 and CO2. Solid-state batteries based on electrolytes with low or zero vapour pressure provide a promising path towards safe, energy-dense storage of electrical energy. In this Review, we consider the requirements and design rules for solid-state electrolytes based on inorganics, organic polymers and organic–inorganic hybrids.

Research Development on K-Ion Batteries.

Abstract: Li-ion batteries (LIBs), commercialized in 1991, have the highest energy density among practical secondary batteries and are widely utilized in electronics, electric vehicles, and even stationary energy storage systems. Along with the expansion of their demand and application, concern about the resources of Li and Co is growing. Therefore, secondary batteries composed of earth-abundant elements are desired to complement LIBs. In recent years, K-ion batteries (KIBs) have attracted significant attention as potential alternatives to LIBs. Previous studies have developed positive and negative electrode materials for KIBs and demonstrated several unique advantages of KIBs over LIBs and Na-ion batteries (NIBs). Thus, besides being free from any scarce/toxic elements, the low standard electrode potentials of K/K+ electrodes lead to high operation voltages competitive to those observed in LIBs. Moreover, K+ ions exhibit faster ionic diffusion in electrolytes due to weaker interaction with solvents and anions than that of Li+ ions; this is essential to realize high-power KIBs. This review comprehensively covers the studies on electrochemical materials for KIBs, including electrode and electrolyte materials and a discussion on recent achievements and remaining/emerging issues. The review also includes insights into electrode reactions and solid-state ionics and nonaqueous solution chemistry as well as perspectives on the research-based development of KIBs compared to those of LIBs and NIBs.

Molecular design for electrolyte solvents enabling energy-dense and long-cycling lithium metal batteries

Abstract: Electrolyte engineering is critical for developing Li metal batteries. While recent works improved Li metal cyclability, a methodology for rational electrolyte design remains lacking. Herein, we propose a design strategy for electrolytes that enable anode-free Li metal batteries with single-solvent single-salt formations at standard concentrations. Rational incorporation of –CF2– units yields fluorinated 1,4-dimethoxylbutane as the electrolyte solvent. Paired with 1 M lithium bis(fluorosulfonyl)imide, this electrolyte possesses unique Li–F binding and high anion/solvent ratio in the solvation sheath, leading to excellent compatibility with both Li metal anodes (Coulombic efficiency ~ 99.52% and fast activation within five cycles) and high-voltage cathodes (~6 V stability). Fifty-μm-thick Li|NMC batteries retain 90% capacity after 420 cycles with an average Coulombic efficiency of 99.98%. Industrial anode-free pouch cells achieve ~325 Wh kg−1 single-cell energy density and 80% capacity retention after 100 cycles. Our design concept for electrolytes provides a promising path to high-energy, long-cycling Li metal batteries. The realization of the full potential of Li metal batteries requires high-performance electrolytes. Here Z. Bao and colleagues develop low-concentration electrolytes with a single-solvent and single-salt formulation, offering promise for high-energy and long-cycling batteries.