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Tumor-associated macrophages (TAMs), are crucial for the survival and development of tumor cells. Heat shock factor 1 (HSF1) is a potent, complex carcinogenesis modulator, and esophageal cancer (EC) patients have a bad prognosis when HSF1 is highly expressed. HSF1's clinical importance and biological role in TAMs are still unknown.The HSF1 expression profile and patient survival information were analyzed from the TCGA database. The infiltration of different types of immune cells in EC was evaluated based on HSF1 gene expression by Sangerbox 3.0. Immunochemistry was employed to assess HSF1 protein expression in 134 individuals with esophageal squamous cell carcinoma (ESCC), proceeded by association with clinicopathological variables. The role of macrophage-driven HSF1 were observed using HSF1-knockdown THP1 cells.High level of HSF1 have a poorer prognosis in individuals with EC. The expressing level of HSF1 was positively related to infiltration of M2 macrophages (P 0.05). The expression of HSF1 in macrophages was an independent factor for DFS (P = 0.002) and OS (P = 0.002) in ESCC cases. HSF1 was up-regulated in IL-4 stimulation THP1 cells in a time-dependent manner. Under the heat stimulation condition, THP1-derived macrophages were more sensitive than tumor cells. Compared to IL-4 induced-THP1 cells control, the HSF1 knockdown in THP1 cell inhibited the growth and proliferation of ESCC cells.The up-regulation of HSF1 was more rapid and could affect the proliferation of tumor cells in IL4-induced macrophages. The expression of HSF1 in TAMs can also serve as a marker for ESCC prognosis.

Manganese oxides (MnOx) have been extensively investigated due to their extremely high theoretical capacities for application as conversion anodes in lithium-ion batteries. However, fully performing their theoretical performance still faces poor electric conductivity and serious volume change upon lithium insertion/extraction. Herein, we demonstrate encapsulating manganese oxide nanoparticles within a conducting polymer polypyrrole (PPy) shell as a facile strategy to overcome such flaws through in situ redox reaction and oxidative polymerization process. Such an in situ method combines the redox reaction between potassium permanganate and tetrahydrofuran to form MnOx nanoparticles and the subsequent oxidative polymerization of pyrrole to form a conductive polypyrrole coating shell by the oxidant KMnO4 into one step. For the as-fabricated products (MnOx@PPy), this tenderly introduced conductive PPy shell highly favors the fast electron transfer and preserves the electrode structure integrity upon repeated cycling. As the anode for LIBs, MnOx@PPy exhibits superior lithium storage performance with a high reversible capacity (1538 mAh·g−1), long-life cyclability (747 mAh·g−1 after 1000 cycles at 1.0C) and durable ratability (574 mAh·g−1 at 2.0C). This work demonstrates that the convenient in situ strategy to form conductive polymer coating shell is effective to improve the performance of conversion anodes and can be extended to other materials for energy storage applications.

Suburban forest ecosystems have a great influence on local climate, especially for mitigating urban heat island effects and dry island effects. To quantify the climate regulation value of forest ecosystem, and provide a reference for regional ecosystem accounting and scientific land management, a new estimation method based on actual evapotranspiration (AET) is proposed and applied in this work. Based on remote sensing, meteorological, and soil data in the years 2000, 2010, and 2020, the annual AET of the forest ecosystem and its dynamic changes were calculated in the new urban area, Guanshanhu District, Guiyang, Guizhou Province, SW China. The climate regulation value is derived from differences in the annual AET of forest ecosystems relative to impervious surfaces. The results showed that: (1) the area of forest ecosystem in Guanshanhu District increased from 2000 to 2010 as a result of ecological engineering but decreased from 2010 to 2020 due to the establishment and expansion of the new urban area, while the area of the impervious surface increased rapidly; (2) the differences in annual AET of forest ecosystem relative to the impervious surface were calculated and subdivided according to different forest types. In 2000, 2010, and 2020, coniferous forests contributed the most to the annual AET difference, followed by coniferous and broad-leaved mixed forests, broad-leaved forests, shrubs, and other forests, respectively; (3) the total climate regulation value of forest ecosystem showed an increasing trend, on the whole, the estimation results were ¥8.78 × 108 in 2000, ¥12.62 × 108 in 2010, and ¥14.75 × 108 in 2020; (4) The average per unit area climate regulation value of all types of forests in the area, based on electricity price in the year 2000, was ¥8.06 × 104/ha in 2000, ¥8.11 × 104/ha in 2010, and ¥10.58 × 104/ha in 2020, the highest portion of per unit area climate regulation value was of coniferous forest, as ¥8.59 × 104/ha in 2000, ¥9.28 × 104/ha in 2010, and ¥11.05 × 104/ha in 2020. This study is a beneficial exploration of forest ecosystem climate regulation value estimation in Guanshanhu District, and the results can provide references for ecological construction in new urban areas.

Li2CO3 is a ubiquitous byproduct in Li-air (O2) batteries, and its accumulation on the cathode could be detrimental to the devices. As a result, much efforts have been devoted to investigating its formation and decomposition, in particular, upon cycling of Li-O2 batteries. At high voltages, Li2CO3 is expected to decompose into CO2 and O2. However, as recognized from the work of many authors, only CO2, and no O2, has been identified, and the underlying mechanism remains uncertain so far. Herein, a solid-state Li-O2 battery (Li|Li6.4La3Zr1.4Ta0.6O12|Au) has been designed to interrogate the Li2CO3 oxidation without interferences from the decomposition of other battery components (organic electrolyte, binder, and carbon cathode) widely applied in conventional Li-O2 batteries. It is revealed that Li2CO3 can indeed be oxidized to CO2 and O2 in a more stable solid-state Li-O2 battery configuration, highlighting the feasibility of reversible operation of Li-O2 batteries with ambient air as the feeding gas.

Ultrathin, ultrastrong, and highly conductive solid-state polymer-based composite electrolytes have long been exploited for the next-generation lithium-based batteries. In particular, the lightweight membranes that are less than tens of microns are strongly desired, aiming to maximize the energy densities of solid-state batteries. However, building such ideal membranes are challenging when using traditional materials and fabrication technologies. Here we reported a 7.1 μm thick heterolayered Kevlar/covalent organic framework (COF) composite membrane fabricated via a bottom-up spin layer-by-layer assembly technology that allows for precise control over the structure and thickness of the obtained membrane. Much stronger chemical/mechanical interactions between cross-linked Kevlar and conductive 2D-COF building blocks were designed, resulting in a highly strong and Li+ conductive (1.62 × 10-4 S cm-1 at 30 °C and 4.6 × 10-4 S cm-1 at 70 °C) electrolyte membrane that can prevent solid-state batteries from short-circuiting after over 500 h of cycling. All-solid-state lithium batteries using this membrane enable a significantly improved energy density.

Lithium garnets have been widely studied as promising electrolytes that could enable the next-generation all-solid-state lithium batteries. However, upon exposure to atmospheric moisture and carbon dioxide, insulating lithium carbonate forms on the surface and deteriorates the interfaces within electrodes. Here, we report a scalable solid sintering method, defined by lithium donor reaction that allows for complete decarbonation of Li6.4La3Zr1.4Ta0.6O12 (LLZTO) and yields an active LiCoO2 layer for each garnet particle. The obtained LiCoO2 coated garnets composite is stable against air without any Li2CO3. Once working in a solid-state lithium battery, the LiCoO2-LLZTO@LiCoO2 composite cathode maintains 81% of the initial capacity after 180 cycles at 0.1 C. Eliminating CO2 evolution above 4.0 V is confirmed experimentally after transforming Li2CO3 into LiCoO2. These results indicate that Li2CO3 is no longer an obstacle, but a trigger of the intimate solid-solid interface. This strategy has been extended to develop a series of LLZTO@active layer materials., Formation of insulating lithium carbonate on surface of lithium garnets hinders their application as solid electrolyte in lithium ion batteries. Here the authors explore a scalable sintering approach to utilize the undesired Li2CO3 and improve the active material-electrolyte interface within cathodes.

Superionic conductors with ionic conductivity on the order of mS cm-1 are expected to revolutionize the development of solid-state batteries (SSBs). However, currently available superionic conductors are limited to only a few structural families such as garnet oxides and sulfide-based glass/ceramic. Interfaces in composite systems such as alumina in lithium iodide have long been identified as a viable ionic conduction channel, but practical superionic conductors employing the interfacial conduction mechanism are yet to be realized. Here we report a novel method that creates continuous interfaces in the bulk of composite thin films. Ions can conduct through the interface, and consequently, the inorganic phase can be ionically insulating in this type of bulk interface superionic conductors (BISCs). Ionic conductivities of lithium, sodium, and magnesium ion BISCs have reached 1.16 mS cm-1, 0.40 mS cm-1, and 0.23 mS cm-1 at 25 °C in 25 μm thick films, corresponding to areal conductance as high as 464 mS cm-2, 160 mS cm-2, and 92 mS cm-2, respectively. Ultralow overpotential and stable long-term cycling for up to 5000 h were obtained for solid-state Li metal symmetric batteries employing Li ion BISCs. This work opens new structural space for superionic conductors and urges for future investigations on detailed conduction mechanisms and material design principles.

Spinal cord injury (SCI) is the most severe result of spine injury, but no effective therapy exists to treat SCI. We have previously shown that the E3 ubiquitin ligase Two RING fingers and DRIL 1 (Triad1) promotes neurite outgrowth after SCI. However, the mechanism by which Triad1 affects neuron growth and the potential involvement of its ubiquitination activity is unclear. Neuroprotective cytokine pleiotrophin (PTN) can promote microglia proliferation and neurotrophic factor secretion to achieve neuroprotection. We find using immunostaining and behavioral assays in rats that the expression of Triad1 and the PTN was peaked at 1 day after SCI and Triad1 improved motor function and histomorphological injury after SCI. We show using flow cytometry and astrocyte/neuronal coculture assays that Triad1 overexpression promoted PTN protein levels, neurotrophic growth factor (NGF) expression, brain-derived neurotrophic factor (BDNF) expression, astrocyte and neuronal viability, and neurite outgrowth but suppressed astrocyte apoptosis, while shRNA-mediated knockdown of Triad1 and PTN had the opposite effects. Ubiquitin ligase murine double mutant 2 (MDM2) has previously been demonstrated to participate in the process of neurite outgrowth and mediate ubiquitination of p53. Furthermore, we demonstrate overexpression of MDM2 downregulated PTN protein levels, NGF expression and BDNF expression in astrocytes, and inhibited neurite outgrowth of neurons. In addition, MDM2 facilitated PTN ubiquitination, which was reversed by Triad1. Finally, we show simultaneous sh-PTN and MDM2 overexpression attenuated the neurite outgrowth-promoting effect of Triad1 overexpression. In conclusion, we propose Triad1 promotes astrocyte-dependent neurite outgrowth to accelerate recovery after SCI by inhibiting MDM2-mediated PTN ubiquitination.

Li–O2 batteries, which have attracted great attention because of their high energy density, suffer from issues such as flammability of organic liquid electrolytes, corrosion of the Li anode and the shuttling effect of redox mediators. Using inorganic solid-state electrolytes (SSEs) can solve such issues. But high resistance at the SSE–electrode interfaces in these batteries hinders their further development. In this study, a “porous framework infiltrating (PFI)” concept is proposed. The framework is created on the surface of a garnet Li6.4La3Zr1.4Ta0.6O12 (LLZTO) ceramic by acid etching. After infiltrating a tiny amount of liquid electrolyte, this framework exhibits nonflammability and is thus ideal for high-safety applications. Moreover, the porous structure increases the contact area between the SSE and cathode, which can lower the interfacial resistance and improve the rate capability. Utilizing a Li–Sn alloy anode, the PFI Li–O2 battery exhibits smooth charging platforms with different rates, a prolonged cycle life and a promising round-trip efficiency. Therefore, the PFI structure provides a new strategy to build safe and high-performance Li–O2 batteries.

The issues at the interface between the solid-state electrolyte (SSE) and electrodes limit the development of all-solid-state lithium batteries (ASSLBs). Herein, we report a LiF/graphene inorganic composite interlayer (ICI) which is in situ constructed at the cathode/garnet interface by electrochemical pre-lithiation of fluorinated graphene (GF). The ICI with flexibility and ion-conductivity can improve the contact between the cathode and garnet electrolyte, and thus enables the ASSLB to stably operate for 60 cycles without any liquid conditions.

Garnet electrolyte is a promising candidate for the development of all-solid-state Li-metal batteries, because of its safety and stability against Li metal. However, its practical application is limited by the difficulty in production of its high-density thin sheet. In this work, we have fabricated garnet thin sheet electrolytes (Li6.4La3Zr1.4Ta0.6O12, LLZTO) by tape-casting technique. By using Li2O as a liquid-phase sintering additive, a high relative density up to 99% was achieved. Electrochemical results show the LLZTO sheets have an ionic conductivity of 5.2 × 10−4 S cm−1 at 30 °C and good cycling stability against Li metal. Based on the sheets, all-solid-state Li/LLZTO/LiFePO4 batteries exhibit excellent reversible cycles at 60 °C and 0.1C with an initial discharge specific capacity of 125.8 mA h g−1 and a retention of 92.3% after 50 cycles. These results indicate that the tape-casting process demonstrated here provides an effective method of producing high-density garnet thin sheet electrolytes for high-performance all-solid-state Li-metal batteries.

Yellow soils developed in limestone weathering materials are representative on Guizhou Plateau, Southwest China. As one of the most important cultivated soils in Guizhou Province, karst yellow soils are generally thin and can be significantly damaged by mild soil erosion. This work used the structural equation model (SEM) to analyze the influence of various factors on runoff generation and sediment loss based on a long time series (2015–2020) of natural rainfall-runoff data and soil erosion data collected from 18 runoff plots in the karst yellow soil region of Southwest China, which reflects the erosion dynamics under natural conditions. Slope runoff plots are the most popular and efficient way to collect data on runoff generation and soil erosion. The findings show that: (1) There were 139 rainfall-runoff occurrences between 2015 and 2020, with moderate rain (10–25 mm) and heavy rain (25–50 mm) events making up the majority. Due to its high frequency and prolonged duration, heavy rain had the greatest impact on the overall rainfall erosivity R value (R). (2) Mean surface runoff (SR) values ranged from 17.37 mm to 133.90 mm, while mean sediment loss rates (SLR) ranged from 1.36 t·ha−1·a−1 to 23.49 t·ha−1·a−1. SR and SLR can be successfully reduced by the forest floor. Broadleaf forest, coniferous forest, mixed forest, and orchard had mean SR values of 19.33%, 12.97%, 16.10%, and 33.38% of fallow land, respectively, and had mean SLR values of 6.90%, 5.79%, 6.34%, and 12.64% of fallow land, respectively. (3) SR generation at the plot scale was substantially linked with 30-min maximum rainfall intensity (I30), while vegetation coverage (VC) and antecedent soil water content (ASW) showed negative direct inference on SR and runoff sediment concentration (RSC) according to SEM analysis. The VC and ASW showed the highest indirect impact on SLR. This study will serve as a scientific reference for the water and soil erosion management in karst yellow soil region and serve as a scientific guidance for regional land use in Southwest China.

Li

Superionic conductors with ionic conductivity on the order of mS cm

Objective: Nasopharyngeal carcinoma (NPC) is a malignant head and neck tumor that is highly prevalent in Southeast Asia. The two traditional NPC markers VCA-IgA (EBV viral capsid antigen) and EA-IgA (EBV early antigen) are limited in the screening and diagnosis of NPC. The purpose of present study is to evaluate the diagnostic value of matrix metalloproteinase-3 (MMP3) in NPC. Methods: The levels of 23 secretory MMPs in serum samples from 15 healthy controls and 26 NPC patients were detected by Cytokine Antibody Array 2000. Immunohistochemistry, Real-time PCR and western bolt were used to detect MMP3 mRNA and protein levels in NPC tissues and cell lines. The serum protein levels of MMP3 were further measured by ELISA in healthy control individuals (n = 200) and NPC patients (n = 206). Results: MMP3 can be expressed and secreted by both NPC and fibroblast cell lines, suggesting that the higher expression of MMP3 protein in both tumor nests and stromal of NPC tissues may be the source of circulating MMP3 in NPC patients. Furthermore, we found out both MMP3 concentration and enzymatic activity were significantly increased in the NPC group (n = 206) than the healthy control group (n = 200) (P < 0.001). However, serum MMP3 enzymatic activity, but not MMP3 concentration, was significantly associated with the progression of NPC. In addition, serum MMP3 activity was more valuable in diagnosis of NPC than its concentration (0.86 vs. 0.78, AUC), and MMP3 activity can improve the diagnosis of NPC by combining with EBV-infection biomarkers VCA-IgA and EA-IgA with a sensitivity of 91.5% and a specificity of 92.3%. Conclusions: This study suggested the combination of MMP3 activity and EBV antibodies may be a useful biomarker for screening and diagnosis of NPC.

Solid-state batteries (SSBs) have already attracted significant attention due to their potential to offer high energy density and excellent safety as compared to the currently used lithium-ion batteries with liquid electrolytes. The use of a lithium anode in SSBs is extremely important to realize these advantages. Starting from the synthesis of a highly conductive cubic garnet solid electrolyte (Li6.375La3Zr1.375Nb0.625O12, LLZNO) using Nb as a structure stabilizer, in this study, we demonstrated the resolution of interfacial problems between the garnet electrolyte and lithium anode and the integration of the lithium anode into garnet-based SSBs by modifying the as-synthesized LLZNO with a Sn thin film. Due to the Sn modification, the interfacial resistances between the garnet electrolyte and the lithium anode decreased approximately 20 times to only 46.6 Ω cm2. The fast and reversible lithium plating/stripping under high current densities and the excellent battery performance of Li/Sn-LLZNO/LiFePO4 full cells were achieved. This improvement is ascribed to the formation of a Li–Sn alloy interlayer, which severs as a self-limited stable and conductive interface, bridging the garnet electrolyte and the lithium anode and enabling fast and stable lithium transport. As a proof-of-concept, this effective surface modification method will offer inspirations to researchers for overcoming the interfacial problems and promoting the development of high-performance SSBs.

Although Li1.3Al0.3Ti1.7(PO4)3 (LATP) solid electrolyte has the advantages of high ionic conductivity , low cost, and satisfying air stability, it is thermodynamically unstable with lithium metal, which could reduce the Ti 4+ to Ti3+ and form a highly resistive interface, leading to the fast degradation of battery performance. Herein, through an in-depth study on the degradation mechanism of LATP by delocalized π electrons in succinonitrile (SN), we propose a novel plastic composite interlayer (PCI) based on succinonitrile and polyacrylonitrile, which can not only realize a rapid and uniform transmission of lithium ions but also localize π electrons, inhibit the continuous deterioration of LATP. Compared with previous battery tests at elevated temperatures or by adding liquid components, the PCI-based Li|Li symmetric cell has achieved a cyclability for more than 300 h at room temperature. Moreover, the discharge capacity of the all-solid-state battery based on PCI still retains 87.9% after 170 cycles at 0.1C, which is in sharp contrast to the 38.6% capacity retention after 50 cycles of LFP/SN/LATP/SN/Li battery. These results show that PCI, as an effective anode interlayer, paves a way for high-performance solid-state batteries based on NASICON-type electrolytes.

Afforestation in the Three North Region (TNR) of China has received wide concern due to the low survival rate and threats to water security associated with the lack of available precipitation for vegetation. It is crucial to provide a spatial layout for revegetation according to the available precipitation to achieve the vegetation cover target. This study investigated the spatial pattern of precipitation, determined the suitable vegetation distribution based on the ecological water requirements and precipitation, and proposed an optimized revegetation scheme by comparing the actual and suitable vegetation patterns. The results indicated that the actual vegetation that matched the pixel-level precipitation accounted for 67.24% of the total vegetation area in the TNR. However, 18.50% of the actual forest, 21.82% of the actual shrublands, and 19.95% of the actual grasslands were overloaded with respect to precipitation. The total suitable vegetation area was reduced slightly compared to the actual vegetation area. There is still some potential for the revegetation of forest and shrublands, mainly those in the eastern and south-eastern parts of the TNR. The optimized revegetation area in the TNR was 3.04 × 106 km2, including a maintenance management type of 2.19 × 106 km2, an upgrade type of 0.49 × 106 km2, and a degradation type of 0.37 × 106 km2. Maintenance management (natural restoration) and transformation to vegetation types with lower ecological water requirements were recognized as important revegetation practices in the TNR. This study provides guidelines to adjust the Three North Shelterbelt Project policies based on precipitation data to reduce the negative impact of revegetation on the hydrological cycle.

Paramount attention has been paid on solid polymer electrolytes due to their potential in enhancement of energy density as well as improvement of safety. Herein, the composite electrolytes consisting of Li-salt-free polyethylene oxides and 200 nm-sized Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 particles interfacially wetted by [BMIM]TF 2 N of 1.8 μL cm −2 have been prepared. Such wetted ionic liquid remains the solid state of membrane electrolytes and decreases the interface impedance between the electrodes and the electrolytes. There is no release of the liquid phase from the PEO matrix when the pressure of 5.0 × 10 4 Pa being applied for 24 h. The interfacially wetted membrane electrolytes show the conductivity of 2.2 × 10 −4 S cm −1 at 20 °C, which is one order of magnitude greater than that of the membranes without the wetted ionic liquids. The conduction mechanism is related to a large number of lithium ions releasing from Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 particles and the improved conductive paths along the ion-liquid-wetted interfaces between the polymer matrix and ceramic grains. When the membranes being used in the solid-state LiFePO 4 /Li and LiFe 0.15 Mn 0.85 PO 4 /Li cells at 25 °C, the excellent rate capability and superior cycle stability has been shown. The results provide a new prospect for solid polymer electrolytes used for room-temperature solid-state lithium batteries.

Solid-state electrolytes with high ionic conductivity, large electrochemical window, good mechanical properties, and easy processability are needed for high-energy solid-state lithium batteries. In this work, composite membranes consisting of lithium garnet (i.e. Li6.4La3Zr1.4Ta0.6O12, LLZTO) particles and Li-salt-free polyethylene oxides (PEOs) are produced as solid-state electrolytes. Li-ion-conducting particles in nano-scale are crucial for the enhancement of conductivity and the membranes containing ~40 nm LLZTO particles exhibit conductivities nearly two orders of magnitude larger than those with the micro-scale ones, which is attributed to the difference in specific surface area related to the percolation effect. Compared to the conventional PEO doped with lithium salt, the insulating PEO in PEO:LLZTO membrane electrolyte is conducive to the suppression of lithium dendrite growth owing to prohibition of current flow. With PEO:LLZTO membrane electrolytes in conductivity of 2.1×10−4 S cm−1 at 30 °C and 5.6×10−4 S cm−1 at 60 °C, the solid-state LiFePO4/PEO:LLZTO/Li and LiFe0.15Mn0.85PO4/PEO:LLZTO/Li cells deliver energy densities of 345 Wh kg−1 (662 Wh L−1) and 405 Wh kg−1 (700 Wh L−1) (without the package weight or volume) with good rate capability and cycling performance. This study suggests that the conjunction of nano-scale Li-ion-conducting particles and an insulating polymer provides a promising solution to produce powerful solid-state electrolytes for high-performance solid-state lithium batteries.

The development of solid-state lithium-oxygen batteries is currently limited primarily by the high solid-solid interfacial resistance and the lack of efficient assembly of electrolyte and electrode. In this work, noncovalent interactions between the cations of an ammonium ionic liquid and both solid electrolytes and carbon air cathodes are introduced. The ionic liquid-based electrolytes (ILE) are solidified on Li6·40La3Zr1·40Ta0·60O12 (LLZTO) nanoparticles and gelated by multi-wall carbon nanotubes (MWCNTs), respectively, to construct LLZTO@ILE quasi-solid-state electrolyte (QSSE) and MWCNTs-LLZTO/ILE gel cathode (GC). The QSSE exhibits a high ionic conductivity of 1.71 × 10−3 S cm−1 at 60 °C, high Li-ion transference number of 0.56, broad electrochemical window of ~4.8 V and good thermal stability. The GC shows outstanding compatibility with QSSE. Quasi-solid-state Li–O2 batteries are assembled by integrating QSSE and GC films with a facile roll forming method, showing a low total interfacial resistance (~87 Ω cm2), and excellent reversible cycles (70 cycles) with low charge overpotential ( 70%) at 60 °C and 200 mA g−1. A 0.12 Ah pouch-type Li–O2 battery was achieved by this method. These results suggest that the noncovalent interactions initiated by IL cations could be an effective approach to solve the solid-solid interface issue and achieve high discharge capacity in solid-state energy storage devices.

All solid-state lithium batteries are constructed by using highly conducting Ta-doped Li7La3Zr2O12 (LLZTO) as the solid electrolytes as well as the supports, coated with composite cathodes consisting of poly(vinylidene fluoride) (PVdF):LiTFSI, Ketjen Black, and carbon-coated LiFePO4 on one side and attached with Li anode on the other side. At 60 °C, the batteries show the first discharge capacity of 150 mAh g−1 at 0.05 C and 93% capacity retention after 100 cycles. As the current density increases from 0.05 C to 1 C, the specific capacity decreases from 150 mAh g−1 to 100 mAh g−1. Further elevated temperature up to 100 °C leads to further improved performance, i.e. 126 mAh g−1 at 1 C and 99% capacity retention after 100 cycles. This good performance can be attributed to the highly conducting ceramic electrolytes, the optimum electronic and ionic conducting networks in the composite cathodes, and closely contacted cathode/LLZTO interface. These results indicate that the present strategy is promising for development of high-performance solid-state Li-ion batteries operated at medium temperature.

W-doped Li 7 La 3 Zr 2 O 12 electrolytes with composition of Li 7-2x La 3 Zr 2-x W x O 12 (LLZWO, x = 0-0.55) were prepared by conventional solid state reaction. The incorporation of W proves beneficial to stabilization of cubic phase and densification of the ceramic, resulting in relative density of 96% and ionic conductivity of 6.6 × 10 −4 S cm −1 at 25 °C. Further analysis indicates that the LLZWO is not only chemically but also electrochemically (at least up to 4.5 V) stable against Li metal anodes. The batteries consisting of Li/LLZWO/Electrolyte-soaked separator/LiNi 0.33 Mn 0.33 Co 0.33 O 2 at 25 °C exhibit the capacity of 142 mAh g −1 at a constant current of 15 mA g −1 at the first discharge, which could run for 20 cycles with capacity retention of 94%. These results indicate that the W-doped LLZO ceramics are promising electrolytes for solid state lithium ion batteries.

Electromagnetic continuous casting (EMCC) exhibits great potential for silicon purification by Al–Si method. Distribution of Al in Al–Si alloys with different aluminium contents during EMCC was investigated. The macrostructure of the Al–Si alloy ingots reveals that the content of primary silicon plates in hypereutectic alloys decreases from the bottom to the top of the ingots, and no obvious primary silicon plate exists in eutectic alloy. The fitting results of aluminium distribution in the alloys reveal two types of aluminium distribution patterns in hypereutectic Al–Si alloys: Scheil model for high temperature solidification and initial transient model for low temperature one. An apparent segregation coefficient of Al is proposed to characterise the solidification process, which is ∼0.83 in the hypereutectic alloys.

Solid-state batteries (SSBs) have seen a resurgence of research interests in recent years for their potential to offer high energy density and excellent safety far beyond current commercialized lithium-ion batteries. The compatibility of Si anodes and Ta-doped Li7La3Zr2O12 (Li6.4La3Zr1.4Ta0.6O12, LLZTO) solid electrolytes and the stability of the Si anode have been investigated. It is found that Si layer anodes thinner than 180 nm can maintain good contact with the LLZTO plate electrolytes, leading the Li/LLZTO/Si cells to exhibit excellent cycling performance with a capacity retention over 85% after 100 cycles. As the Si layer thickness is increased to larger than 300 nm, the capacity retention of Li/LLZTO/Si cells becomes 77% after 100 cycles. When the thickness is close to 900 nm, the cells can cycle only for a limited number of times because of the destructive volume change at the interfaces. Because of the sustainable Si/LLZTO interfaces with the Si layer anodes with a thickness of 180 nm, full cells...

The lithium garnet ceramic has been considered as one of promising solid-state electrolytes for secondary lithium batteries. However, improvement of its ionic conductivity is hindered by the high porosity related to the severe volatilization of lithium components during sintering. In order to find the solution for this problem, Li2O additives in concentration of 2–8 wt.% were introduced into the cubic Li6.75La3Zr1.75Ta0.25O12 (LLZTO) at the solid-state reaction processes. It is found that the Li2O additives lead to formation of glassy-like phases at the grain boundaries related to the liquid-phase sintering behavior, which eliminates the residual pores therein and increases the relative density from 91.5% to 97.3%. Measurement of conductivity indicates that 6 wt.% is the optimum concentration of Li2O which leads to an ionic conductivity of 6.4 × 10− 4 S cm− 1 at room temperature. This value is approximately 3 times larger than that of the ceramic without the additive.