Rechargeable Li-metal batteries using high-voltage cathodes can deliver the highest possible energy densities among all electrochemistries. However, the notorious reactivity of metallic lithium as well as the catalytic nature of high-voltage cathode materials largely prevents their practical application. Here, we report a non-flammable fluorinated electrolyte that supports the most aggressive and high-voltage cathodes in a Li-metal battery. Our battery shows high cycling stability, as evidenced by the efficiencies for Li-metal plating/stripping (99.2%) for a 5 V cathode LiCoPO (~99.81%) and a Ni-rich LiNiMnCoO cathode (~99.93%). At a loading of 2.0 mAh cm, our full cells retain ~93% of their original capacities after 1,000 cycles. Surface analyses and quantum chemistry calculations show that stabilization of these aggressive chemistries at extreme potentials is due to the formation of a several-nanometre-thick fluorinated interphase.

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Development of electrolytes that simultaneously have high ionic conductivity, wide electrochemical window, and lithium dendrite suppression ability is urgently required for high‐energy lithium‐metal batteries (LMBs). Herein, an electrolyte is designed by adding a countersolvent into LiFSI/DMC (lithium bis(fluorosulfonyl)amide/dimethyl carbonate) electrolytes, forming countersolvent electrolytes, in which the countersolvent is immiscible with the salt but miscible with the carbonate solvents. The solvation structure and unique properties of the countersolvent electrolyte are investigated by combining electroanalytical technology with a Molecular Dynamics simulation. Introducing the countersolvent alters the coordination shell of Li+ cations and enhances the interaction between Li+ cations and FSI− anions, which leads to the formation of a LiF‐rich solid electrolyte interphase, arising from the preferential reduction of FSI− anions. Notably, the countersolvent electrolyte suppresses Li dendrites and enables stable cycling performance of a Li||NCM622 battery at a high cut‐off voltage of 4.6 V at both 25 and 60 °C. This study provides an avenue to understand and design electrolytes for high‐energy LMBs in the future.

Li-rich layered-oxide cathodes have the highest theoretical energy density among all the intercalated cathodes, which have attracted intense interests for high-energy Li-ion batteries. However, O3-structured layered-oxide cathodes suffer from a low initial Coulombic efficiency (CE), severe voltage fade, and poor cycling stability because of the continuous oxygen release, structural rearrangements due to irreversible transition-metal migration, and serious side reactions between the delithiated cathode and electrolyte. Herein, we report that these challenges are migrated by using a stable O2-structured Li1.2­Ni0.13­Co0.13­Mn0.54­O2 (O2-LR-NCM) and all-fluorinated electrolyte. The O2-LR-NCM can restrict the transition metals migrating into the Li layer, and the in situ formed fluorinated cathode–electrolyte interphase (CEI) on the surface of the O2-LR-NCM from the decomposition of all-fluorinated electrolyte during initial cycles effectively restrains the structure transition, suppresses the O2 release, and thereby safeguards the transition metal redox couples, enabling a highly reversible and stable oxygen redox reaction. O2-LR-NCM in all fluorinated electrolytes achieves a high initial CE of 99.82%, a cycling CE of >99.9%, a high reversible capacity of 278 mAh/g, and high capacity retention of 83.3% after 100 cycles. The synergic design of electrolyte and cathode structure represents a promising direction to stabilize high-energy cathodes.

Solid-state Li metal batteries (SSLMBs) have emerged as an important energy storage technology that offers the possibility of both high energy density and safety by combining a Li metal anode...

Soybean yield is a complex quantitative trait, which is greatly affected by environmental conditions. The main objective of this study is not only to identify specific traits contributing to yield in different latitudes, which can be further used in breeding, but also to identify the outperforming varieties, as this can help to select new lines with these traits. One hundred and seventy-three soybean genotypes were tested in three different ecological environments, including Harbin, Changchun, and Shenyang in China during 2015-2016 cropping seasons. The evaluation on the different agronomic and physiological traits indicated that the soybean varieties with higher plant height, more nodes of main stem, branches, pods, grains, and 100-grain weight, or longer growth periods may have higher yield. Pods, grains and 100-grain weight can be used as direct selection criteria for yield increase, and likewise the other traits such as plant height, nodes of main stem, branches, growth periods indirectly affected yield by affecting the three traits above. The effect of genotype × environment (G × E) interaction on different agronomic traits was significant. The representativeness and discriminability for grains yield per plant was the most significant in Harbin, which could be used to screen varieties with high yield and wider adaptability. Genotype "Suinong 1" was considered stable with higher value of grain yield per plant than other genotypes used in this study. As the yield of certain soybean cultivars may be significantly reduced if they are grown in a region as little as 2°N beyond its normal cultivation latitudes, therefore, the identification and analysis on the stable and widely adaptive soybean genotypes would be very important, and it would provide the significant reference accordance of soybean variety selection for the soybean breeders.

Rechargeable Zn‐ion batteries (ZIBs) are widely regarded as promising candidates for large‐scale energy storage applications. Like most multivalent battery systems (based on Zn, Mg, Ca, etc.), further progress in ZIB development relies on the discovery and design of novel cathode hosts capable of reversible Zn2+ (de)intercalation. Herein, this work employs VPO4F as a ZIB cathode and explores ensuing intercalation mechanisms along with interfacial dynamics during cycling to quantify the water dynamics in concentrated electrolytes and/or hybrid aqueous‐non aqueous (HANEs) electrolyte(s). Like most oxide‐based cathode materials, proton (H+) intercalation dominates electrochemical activity during discharge of ZnxHyVPO4F in aqueous media due to the hydroxylated nature of the interface. Such H+ electrochemistry diminishes low‐rate and/or long‐term electrochemical performance of ZIBs which inhibits implementation for practical applications. Thus, quantification of the water dynamics in various electrolytes is demonstrated for the first time. Detailed investigations of water mobility in various concentrated electrolytes and HANEs systems enable the design of an electrolyte that enhances aqueous anodic stability and suppresses water/proton activity during discharge. Tuning Zn2+/H+ intercalation kinetics simultaneously allows for a high voltage (1.9 V) and long‐lasting aqueous zinc‐ion battery: Zn|Zn(OTf)2·nH2O‐PC|ZnxHyVPO4F.

Residual Li compounds are inevitably present in the form of Li 2 O, LiOH, and Li 2 CO 3 on the surface of layered cathode materials, which not only causes slurry gelation in the cathodecoating process but also degrades liquid electrolyte in the batteries. Owing to their strong alkaline nature, the residual Li compounds can react with acidic LiPF 6 to form Li 3 PO 4 and LiF, two of the main components of robust solid electrolyte interphases. By demonstrating LiNi 0.80 Co 0.10 Mn 0.10 O 2 (NCM811) as an example in this work, we simply dissolved a small amount of LiPF 6 into the cathode-coating slurry, finding that as the amount of LiPF 6 is controlled in the 0.5-1.0 wt % range versus the mass of NCM811, the LiPF 6 additive not only improves the cycling stability but also enhances rate capability of the Li/ NCM811 cells. The former is because the strongly alkaline residual Li compounds react with acidic LiPF 6 to form stable Li 3 PO 4 and LiF. The latter is attributed to a reduction in the surface layer resistance on the cathode, as suggested by the results of surface chemistry and impedance analyses.[a] Dr.