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A reversible SO42−/S2O32− redox couple is introduced to passivate the LCO cathode surface via an additive-assisted electrolyte, which endows high-voltage Li ion batteries with superior cycling stability.

Ionic conductivity improvement is achieved in “water-in-salt” electrolytes by confinement in 2D membrane-based nanochannels due to functional group-induced stratification. This benefits the higher performance of aqueous batteries.

The superior lithium storage performance of commercially available Cu2S under ultra-low temperature (−60 °C) is uncovered. The detailed reaction mechanism and mechanistic understanding of the excellent low-temperature performances are proposed.

The development of conductive covalent organic frameworks (COFs) with high stability is desirable for the practical applications in optoelectronics and energy storage. Herein, we developed a new kind of Janus dione-based COF, which is fully sp

The performance of current lithium-ion batteries (LIBs) is severely impaired by low temperatures, which require the development of powerful electrolytes with widen liquidity, facilitated ion diffusion ability, and lower desolvation energy. The keys lie in establishing mild interactions between Li+ and solvent molecules internally, which is hard to realize in commercial ethylene carbonate (EC) based electrolytes due to the strong coordination of EC to Li+. To address this challenge, we tailored the solvation structure with low-ε solvent dominated coordination and unlocked EC via electronegativity regulation of carbonyl oxygen. The modified electrolytes retain considerable ion conductivity (1.46 mS/cm) at -90 ℃, remain liquid at -110℃, and facilitate Li+ desolvation. Consequently, 4.5V graphite-based pouch cells perform stably with ~98% capacity retention and no lithium dendrite formation over 200 cycles at -10 ℃. These cells also retain ~60% of their room-temperature discharge capacity at -70 ℃, and miraculously remain functional even below -100 ℃. This design strategy of breaking the solvation dominance of EC via electron engineering can be extended to other alkali-metal-ion batteries at extremely low temperature.

Abstract: Immobilized lipase has played an essential role in the chemical and biological sciences as a viable alternative to standard chemical catalysts. Glutaraldehyde is a low-cost crosslinking agent at risk of being superseded by developing crosslinking compounds with biocompatible, biodegradable, and non-toxic characteristics. The multipoint covalent treatment method using glutaraldehyde has both advantages and disadvantages. Immobilization techniques can be improved to improve the overall performance of immobilized lipase. The most recent update on lipase immobilization with multipoint covalent treatment by glutaraldehyde was summarized in this review. Covalent binding lipase on pre-activated support and aggregation-crosslinking lipase into crosslinked enzyme aggregates (CLEAs) or adsorption-crosslinking lipase on support are the most common immobilization techniques. Based on the above technologies, the advancement trends in important domains, such as the advancement of supports, additives, reactors, and cross-linking agents, are summarized. In addition, the application of the improved immobilized lipase by glutaraldehyde in the production of fatty acids, glycerides, biodiesel, and drug precursors was reviewed. In view of this, we put forward further studies on multipoint covalent treatment in lipase immobilization with glutaraldehyde. Various analytical methods are required to provide additional information about the structure of glutaraldehyde and its crosslinked products for assisting the proper immobilization conditions. Applying the composite strategy can also bring new opportunities for improving the efficiency of biological catalysts.

This work proposes a Si–O bond strategy to enhance the electrochemical stability of solvents, pioneering the direction of less-fluorinated electrolytes for eco-friendly and practical Li metal batteries.

Self-purifying electrolyte effectively eliminates the reactive pernicious species and endows high energy Li ion batteries with stable long-term cycling.

Stable electrode-electrolyte interphases on both electrodes are indispensable to warrant cycling stability of high-voltage Li-metal batteries. Here, we reveal a unique cooperative reaction mechanism to form protective interphase layers on both Li-metal anode and high-voltage cathodes, which is exemplified by a multifunctional additive ethoxy(pentafluoro)cyclotriphosphazene (PFPN). The F-rich PFPN first reacts with Li-metal anode to form LiF-rich solid electrolyte interphase (SEI), which stabilizes the Li deposition/dissolution processes. Meanwhile, the in-situ generated PFPN derivatives with a de-fluorated structure are prone to be oxidized on cathode, forming a robust cathode-electrolyte interphase (CEI) to prevent electrolyte oxidation and electrode degradation at high voltage. With PFPN to harness the aggressive battery electrodes, Li-metal batteries with high-voltage LiCoO2 (4.5 V) and LiNi0.5Mn1.5O2 (4.9 V) cathodes exhibit improved cycling stability and rate capability. In particular, the LiNi0.5Mn1.5O2|Li full cell with limited Li supply (N/P =7.6) demonstrates outperformed capacity retention of 90.7 % after 100 cycles, which is almost twice that of the cell using PFPN-free conventional electrolyte (47.5 %).

Anti-perovskite type Li2 OHCl was previously studied as a solid-state Li+ conductor. Here, we report that the Li2 OHCl can be electrolyzed at 3.3 V or 4.0 V, with the creation of O2 /HCl gases and the release of 2 equiv. Li+ via two different decomposition routes, depending on the acidity of electrolyte. In the electrolyte with trace acid, the Li2 OHCl is oxidized at a constant voltage of 3.3 V. In neutral electrolyte, the oxidization of Li2 OHCl starts at 4.0 V, but the produced HCl will increase the acidity of electrolyte and lead to a voltage drop to 3.3 V for the electrolysis of Li2 OHCl. The electrolysis of Li2 OHCl delivers a lithium releasing capacity as high as 810 mAh g-1 , with an equivalent Li-deposition or Li-intercalation on anode, making it a promising candidate as a Li reservoir for prelithiation of anode. Using Li2 OHCl as the lithium source, silicon-carbon (Si@C) composite anode can be effectively prelithiated. The full cells composed of LiNi0.8 Mn0.1 Co0.1 O2 (NMC811) cathode and prelithiated Si@C anode exhibited increased capacities with the increment of prelithiation dosages.

The lithium metal anode is considered as the ultimate choice for high-energy-density batteries. However, the organic-dominated solid electrolyte interphase (SEI) formed in carbonate electrolytes ha...

A comprehensive understanding of the solid–electrolyte interphase (SEI) composition is crucial to developing high-energy batteries based on lithium metal anodes. A particularly contentious issue concerns the presence of LiH in the SEI. Here we report on the use of synchrotron-based X-ray diffraction and pair distribution function analysis to identify and differentiate two elusive components, LiH and LiF, in the SEI of lithium metal anodes. LiH is identified as a component of the SEI in high abundance, and the possibility of its misidentification as LiF in the literature is discussed. LiF in the SEI is found to have different structural features from LiF in the bulk phase, including a larger lattice parameter and a smaller grain size (

The hydrolysis of AB has been regarded as a kind of secure and efficient method for hydrogen generation. However, the development of economical and stable catalysts with high catalytic activities r...

Owing to their high capacity and low working potential, Si-based anodes are regarded as potential alternatives to graphite anodes to meet the higher requirements of Li-ion batteries (LIBs). However, high volume change causes the fracturing and pulverization of the bulk anode and continuous side reactions, which are more severe in large-particle Si anodes, limiting its practical application. Herein, to build a low-cost battery system, we chose a common industrial waste product, Al–Si microparticles (Al–SiMPs, ∼30 μm), as the anode for LIBs and coupled it with a 2.0 M LiFP6 2-MeTHF electrolyte to support its operation. The Al–SiMP anode showed a high specific capacity and a significantly improved electronic conductivity, ensuring high energy and power densities. An ultra-high initial coulombic efficiency (iCE) of 91.6% and a cycling CE of ∼99.9% were obtained in the half-cells, which delivered a capacity of 1300 mA h g−1 and maintained 95.3% after 100 cycles. Paired with low-cost and high-safety LiFePO4 as the cathode, the LFP||Al–SiMP full cells showed decent cycling stability and exhibited a considerable cost advantage, demonstrating a competitive solution for stationary energy storage.

Sn metal is believed to be one of the most promising alternative anodes to commercial graphite thanks to the high theoretical capacity and abundant storage. However, large volume change results in pulverization of the bulk electrode, which is more serious in microsized particles, leading to rapid capacity degradation. Therefore, microsized Sn was never successfully applied as the anode for Li-ion batteries. Herein, we report that the as-received Sn microparticles (325 mesh, or ∼45 μm) could be directly used as anodes for LIBs in 2.0 M LiPF6 2-MeTHF or 2.0 M LiPF6 THF/2-MeTHF electrolyte, delivering a high capacity of ∼750 mA h g−1, initial coulombic efficiency of >90%, average cycling coulombic efficiency of ∼99.9%, and capacity retention of 84.1% after 400 cycles at a rate of 2C. This work demonstrated that alloying anodes could be realized by exploring compatible electrolytes and forming compact SEI layers, representing a breakthrough for commercialization of LIBs based on alloying anodes.

Electrolyte engineering advances Li metal batteries (LMBs) with high Coulombic efficiency (CE) by constructing LiF-rich solid electrolyte interphase (SEI). However, the low conductivity of LiF disturbs Li

Li-ion batteries (LIBs) now have made inroads into the electric vehicle market with high energy densities, yet they still suffer from slow kinetics limited by the graphite anode. Here, we design electrolytes enabling extreme fast charging (XFC) of microsized graphite anode without Li plating. The comprehensive characterizations and simulations on the diffusion of Li+ in the bulk electrolyte, charge-transfer process, and the solid electrolyte interphase (SEI) demonstrate that high ionic conductivity, low desolvation energy of Li+ and protective SEI are essential for XFC. Based on the criterion, two fast-charging electrolytes are designed. Low-voltage 1.8 M LiFSI in 1,3-Dioxolane (DOL) ether electrolyte is for LiFePO4||graphite cells, while high-voltage 1.0 M LiPF6 in a mixture of 4-Fluoroethylene Carbonate (FEC) and Acetonitrile (AN) (7:3 by vol.) is for LiNi0.8Co0.1Mn0.1O2||graphite cells. The former electrolyte enables the graphite electrode to achieve 180 mAh g−1 at 50C (1C=370 mAh g-1), which is 10 times higher than that with conventional electrolyte. The latter electrolyte enables LiNi0.8Co0.1Mn0.1O2||graphite cells (2 mAh cm−2, N/P ratio = 1) to provide a record-breaking reversible capacity of 170 mAh g-1 at 4C charge and 0.3C discharge. This work unveils the key mechanisms for XFC and provides instructive electrolyte design principles for practical fast-charging LIBs with graphite anodes.

Li metal, with the lowest thermodynamically achievable negative electrochemical potential and the highest specific capacity (3860 mAh g−1), is the ultimate anode choice for Li batteries. However, the highest reported Li plating/stripping Coulombic efficiency (CE) of 99.5% after extensive efforts is still too low for the Li metal-free (all the Li metal in cycling comes from cathode, without anode pre-lithiation) Li metal batteries. The low CE is attributed to both non-uniform Li plating/stripping on the lithiophobic Cu current collector and Li dendrite growth through lithiophilic organic–inorganic solid electrolyte interphase (SEI) formed in carbonate electrolytes. Here, we use a lithiophilic Bismuth graphite blend (Bi–Gr) substrate to replace lithiophobic Cu current collector to seed a uniform Li nucleation, and form a lithiophobic LiF-rich SEI rather than lithiophilic organic-rich SEI to suppress Li dendrite growth. Molecular dynamics simulations reveal the preferential reduction of anions in 2.0 M LiPF6 in tetrahydrofuran/2-methyl tetrahydrofuran (2.0 M LiPF6–mixTHF) electrolyte to generate LiF-rich SEI on plated Li. Bi–Gr substrate and 2.0 M LiPF6–mixTHF electrolyte enable the Li anodes to achieve a record high CE of 99.83% at a high capacity of 1.0 mAh cm−2 and current of 0.5 mA cm−2. The Bi particles serve as dispersed nucleation centers that promote uniform Li deposition with strong adhesion to the substrate to avoid dead Li, while the lithiophobic LiF-rich SEI promotes lateral Li growth and suppresses the vertical Li dendrite growth even at a high current density of 3.0 mA cm−2 and high areal capacities of 3.0 mAh cm−2. The regulation of Li nucleation and growth enables the Li metal-free LiFePO4 full cells to achieve 100 cycles at a practical areal capacity of >2.0 mAh cm−2. This manuscript highlights the benefits of simultaneous substrate design to improve Li nucleation and electrolyte design to promote lithiophobic SEI growth, enabling a promising and practical route Li metal-free Li metal batteries.

The electrolytes in lithium metal batteries have to be compatible with both lithium metal anodes and high voltage cathodes, and can be regulated by manipulating the solvation structure. Herein, to enhance the electrolyte stability, lithium nitrate (LiNO3 ) and 1,1,2,2-tetrafuoroethyl-2',2',2'-trifuoroethyl(HFE) are introduced into the high-concentration sulfolane electrolyte to suppress Li dendrite growth and achieve a high Coulombic efficiency of >99 % for both the Li anode and LiNi0.8 Mn0.1 Co0.1 O2 (NMC811) cathodes. Molecular dynamics simulations show that NO3 - participates in the solvation sheath of lithium ions enabling more bis(trifluoromethanesulfonyl)imide anion (TFSI- ) to coordinate with Li+ ions. Therefore, a robust LiNx Oy -LiF-rich solid electrolyte interface (SEI) is formed on the Li surface, suppressing Li dendrite growth. The LiNO3 -containing sulfolane electrolyte can also support the highly aggressive LiNi0.8 Mn0.1 Co0.1 O2 (NMC811) cathode, delivering a discharge capacity of 190.4 mAh g-1 at 0.5 C for 200 cycles with a capacity retention rate of 99.5 %.

Lithium sulfur batteries (LSBs) are promising next-generation rechargeable batteries due to the high gravimetric energy, low cost, abundance, nontoxicity, and high sustainability of sulfur. However, the dissolution of high-order polysulfide in electrolytes and low Coulombic efficiency of Li anode require excess electrolytes and Li metal, which significantly reduce the energy density of LSBs. Quasi-solid-state LSBs, where sulfur is encapsulated in the micropores of carbon matrix and sealed by solid electrolyte interphase, can operate under lean electrolyte conditions, but a low sulfur loading in carbon matrix (

Lithium batteries with Si, Al or Bi microsized (>10 µm) particle anodes promise a high capacity, ease of production, low cost and low environmental impact, yet they suffer from fast degradation and a low Coulombic efficiency. Here we demonstrate that a rationally designed electrolyte (2.0 M LiPF6 in 1:1 v/v mixture of tetrahydrofuran and 2-methyltetrahydrofuran) enables 100 cycles of full cells that contain microsized Si, Al and Bi anodes with commercial LiFePO4 and LiNi0.8Co0.15Al0.05O2 cathodes. Alloy anodes with areal capacities of more than 2.5 mAh cm−2 achieved >300 cycles with a high initial Coulombic efficiency of >90% and average Coulombic efficiency of >99.9%. These improvements are facilitated by the formation of a high-modulus LiF–organic bilayer interphase, in which LiF possesses a high interfacial energy with the alloy anode to accommodate plastic deformation of the lithiated alloy during cycling. This work provides a simple yet practical solution to current battery technology without any binder modification or special fabrication methods. Chunsheng Wang and colleagues develop an electrolyte strategy to enable the use of commercially available microsized alloys, such as Si–Li, as high-performance battery anodes. They ascribe its success to the formation of robust LiF-rich layers as the solid–electrolyte interface.