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Employing the solid polymer electrolyte (SPE) instead of traditional liquid electrolyte is an effective way to develop high safety and high-energy density solid-state lithium batteries. Herein, for the first time, the Ni3B2O3 (NBO) nanorods are incorporated into polyethylene oxide (PEO)-based SPE. Particularly, the optimized NBO-embedded SPE shows a high ionic conductivity of 8.5 × 10−5 S cm−1 at 30 °C, lowering the operating temperature of PEO-based SPE substantially. The corresponding LiFePO4/Li battery demonstrates a high discharge capacity of 154 mAh g−1 after 80 cycles at 0.2 C under 30 °C, with favorable capacity retention of 97.5%. The remarkable properties are attributed to the high ionic conductivity of modified SPE at ambient temperature, which is resulted from the decreased crystallinity and melting transition point, increased movement of PEO chain, and promotion of lithium salt dissociation, as well as the formation of the lithium ion migrating pathway on the interface between PEO and NBO nanorods.

In this study, a material-oriented metallurgical strategy, which is of such characteristics as short process, energy conservation and cost saving, is proposed to treat high-grade nickel matte and simultaneously produce LiNi0.80Co0.15Al0.05O2 cathode material for lithium ion batteries. This process is mainly composed of four steps, which is oxidation roasting, two-stage leaching, purification and material synthesis. First, high-grade nickel matte is roasted to eliminate sulfur under air atmosphere. Then the roasted product is first leached to selectively remove 78.10% Cu with little Ni and Co extraction at atmospheric temperature under optimum conditions (25 °C, HCl 1.50 mol L−1, L/S 7.0, 30 min). After that, 96.23% Ni, 96.58% Cu and 84.18% Co are extracted in thermal leaching process under optimum conditions (70 °C, HCl 3.0 mol L−1, L/S 10.0, 120 min), leaving Fe, Zn and Ca in residue. The obtained lixivium is purified by solvent extraction method to adjust the mass ratio of Cu and Ni to the range that meets the requirement for preparation of cathode material. Finally, LiNi0.80Co0.15Al0.05O2 material is produced by spray pyrolysis and sintering. The electrochemical performance of the resulting material is comparable with that prepared from analytical reagents, indicating such process can realize the comprehensive utilization of high-grade nickel matte.

Presentation:Addressing bias in big data and AI for healthcare: a call for open science

Summary Low-cost, scalable energy storage is the key to continuing growth of renewable energy technologies. Here a battery with sedimentary slurry electrode (SSE) is proposed. Through the conversion of discrete particles between sedimentary and suspending types, it not only inherits the advantages of semi-solid flow cell but also exhibits high energy density and stable conductive network. Given an example, the zinc SSE (ZSSE) delivers a large discharge capacity of 479.2 mAh g−1 at 10 mA cm−2. More importantly, by renewal of the slurry per 20 cycles, it can run for 112 and 75 cycles before falling below 80% of designed capacity under 10 mA cm−2 (20% DODZn) and 25 mA cm−2 (25% DODZn), respectively. The lost capacity after cycles is able to recover after slurry renewal and the end-of-life SSE can be easily reused by re-formation. The concept of SSE brands a new way for electrochemical energy storage., Graphical Abstract, Highlights • A renewable semi-solid sedimentary slurry battery is proposed • Lost capacity after cycles is able to recover after slurry renewal • End-of-life SSE can be easily reused by re-formation, Energy Materials; Energy Storage; Energy Systems; Materials Characterization

To suppress the capacity fade of Li-rich Li1.2Ni0.13Co0.13Mn0.54O2 material as cathode materials for lithium-ion battery, we introduce a LiF coating layer on the surface to improve the cycling performance of Li1.2Ni0.13Co0.13Mn0.54O2 material. The modified sample shows a capacity of 163.2 mAh g−1 with a capacity retention of 95% after 100 cycles at a current density of 250 mA g−1, while the pristine sample only delivers a capacity of 129.9 mAh g−1 with a capacity retention of 82%. Compared with the pristine material, the LiF-modified sample exhibits an obvious enhancement in the electrochemical performance, which will be very beneficial for this material to be commercialized on the new energy vehicles and other related areas.

In this paper, SiOx@TiO2/C fibers with TiO2/C composite layer were successfully prepared by one-step electrospinning. Carbon coating can enhance conductivity and act as bulk expansion buffer matrix, while TiO2 coating is beneficial to improving the mechanical stability of composite. Thus, a highly effective and stable conductive network is formed. Benefited from the protection of TiO2/C coating layer, SiOx@TiO2/C fibers demonstrates enhanced electrochemical performance. It exhibites an initial charge capacity of 1125.3 mAh g−1 at 0.1 A g−1, and a stable charge capacity of 855.0 mAh g−1 can be retained with a retention of 89.5% after 100 cycles at 0.4 A g−1, which is better than that of M-SiOx (32.3%) and SiOx@C (52.5%) materials. Moreover, SiOx@TiO2/C fibers show a high charge capacity of 640.4 mAh g−1 after 200 cycles cycled at a high current density of 1 A g−1.

In this work, Sn is used to dope the Li-rich cathode material to improve the electrochemical performance of Li ion battery. After Sn treatment, the lattice parameters a , c and lattice volume V become larger. Compared with the pristine sample, the Sn-contained samples show longer plateaux at about 4.5 V in the first charging process, which means that Sn can activate the Li 2 MnO 3 component. Meanwhile, with appropriate content of Sn doping, the sample exhibits enhanced rate capability and cycling stability. Especially, the sample S10 shows the best electrochemical performance, with a capacity retention of 88.66% after 100 cycles at 1 C (1 C=250 mA g −1 ). The mechanisms of Sn doping have also been investigated. The increased activation of Li 2 MnO 3 is due to the improved conductivity of Li 2 MnO 3 phase by Sn doping, and the enhanced electrochemical performance is mainly ascribed to the increased ability of Li ion diffusing into bulk phase and the improved structure stability during the prolonged charge-discharge cycles. It is suggested that Sn doping is an effective way to improve the electrochemical performance of Li-rich cathode material.

The composite of Co 3 O 4 , Co and graphitized carbon is synthesized by carbonization and cobalt-catalyzed-graphitization of carboxymethyl chitosan, followed by low-temperature thermal oxidation. At the high temperature, the Co(+2) is reduced to metallic Co and the produced Co acts as a catalyst for the graphitization of the pyrolytic carbon. The low-temperature oxidation is conducted to selectively oxidize Co to Co 3 O 4 while the carbon remains unreacted. The structure analysis indicates that three crystal phases (graphite, metallic Co, Co 3 O 4 ) accompanied with amorphous carbon are co-existed in the composite. Morphological results demonstrate that a lot of graphite grains around the Co element are distributed in the carbon. The electrochemical testing results indicate that the composite shows good electrochemical performance. It delivers a reversible capacity of 843 mAh g −1 at low current density, and remains 88.9% after 60 cycles at 200 mA g −1 . Even performed at 1 A g −1 , it also exhibits 493 mAh g −1 . The performance improvement is mainly due to the high capacity of Co 3 O 4 , high conductivity of graphitic carbon and metallic cobalt, the porous structure offering enough ion transport pathways and relieving the strain during cycling.

Li[Li 0.2 Mn 0.54 Ni 0.13 Co 0.13 ]O 2 materials doped with different Zr contents are studied using X-ray diffractometry (XRD), energy dispersive X-ray analysis (EDX), scanning electron microscopy (SEM), charge–discharge measurements, AC impedance spectroscopy as well as cyclic voltammetry. These results demonstrate that the element Zr is distributed uniformly in these materials. With the increase of Zr content, the lattice parameters a , c and lattice volume V become larger. The discharge cycling curves of cells show that Zr doping enhances cycle life compared with the undoped one. The sample with x =0.01 shows the highest capacity and best cycling performance, especially at high current density. The Li[Li 0.2 Mn 0.54− x /3 Ni 0.13− x /3 Co 0.13− x /3 Zr x ]O 2 ( x =0.01) delivers a capacity of 133.6 mA h g −1 (after 100 cycles) at the current density of 250 mA g −1 , corresponding to the capacity retention of 83.8%. The favorable performance of the doped samples could be attributed to its enhanced structural stability and Li + mobility.

The x LiVPO 4 F– y Li 3 V 2 (PO 4 ) 3 composite cathode materials have been synthesized through a soft chemical route with mechanical activation assistance followed by low-temperature calcination. Structural analysis indicates that two phases, i.e. monoclinic Li 3 V 2 (PO 4 ) 3 and triclinic LiVPO 4 F coexist in the composites. With the addition of LVP, the average particle size becomes smaller. The prepared composite materials show good electrochemical performance, and especially a good cyclic performance, the most suitable x / y ratio being 1:5 where the sample can deliver a reversible capacity of 139 mA h g −1 .

Nonprecious bifunctional electrocatalysts with satisfactory cost and high catalytic performance toward oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are essential to promote the commercialization of metal-air batteries. Herein, 3D honeycombed hierarchical porous N, O-doping carbon (HHPC) is fabricated via a facile and scalable strategy of hard template-activator assisted pyrolysis. The obtained HHPC displays unique macro-meso-microporous framework, N, O-codoped effect and order-disorder hybrid characteristic, providing sufficient space for O2 and electrolyte transport, abundant defect sites, enhanced electronic conductivity and stability for oxygen conversion reaction. As such, the HHPC exhibits superior bifunctional electrocatalytic activity with a narrow ΔE value of 0.8 V. And a long-term stability and reversibility with a narrow voltage gap increasing of 0.09 V over 1165 cycles (∼388 h) at 10 mA cm−2 are achieved in the HHPC-based rechargeable Zn-air battery, outperforming most of the state-of-the-art carbon-based Zn-air batteries.

A two stage hydrochloric acid leaching process is proposed for the treatment of lepidolite and recovery of alkali metals. The separation characteristics of aluminum and fluoride in the leachate were also determined. The transformation of lepidolite into silica-like residue was tentatively identified through X-ray diffraction measurements. The leach liquor was heated and concentrated and by evaporation to drive off to remove some of the hydrogen chloride and hydrogen fluoride from the acidic leachate, followed by cooling to deposit crystals. This yielded an overall hydrogen chloride and hydrogen fluoride removal of 25.4% and 2.52%, respectively. The main components of the crystals were aluminum and potassium chlorides, with small amounts of fluoroaluminate, polyaluminum chloride, and aluminum hydroxyfluoride. The crystals were calcined at 623 K, with a further 43.9% of hydrogen chloride and 4.33% of hydrogen fluoride being driven off and captured by adsorption equipment, which was beneficial for the subsequent separation of impurities. Investigation of the major mineral phases revealed that lower temperature calcination of the crystals tended to produce less-soluble polyaluminum chloride, aluminum hydroxyfluoride, fluoaluminate, and alumina. Water leaching of crystals after calcination at 623 K gave a leach liquor with 7.74 g/L of lithium, 0.15 g/L of aluminum and 0.25 g/L of fluoride. The fluoaluminate in the leach liquor led to the production of secondary precipitates after neutralization. The [AlFn]3-n species were partially dissociated to F− and Al(OH)4− at a strongly basic pH. The residual aluminum and fluoride concentrations were 0.01 g/L and 0.05 g/L, respectively, at the pH of 9. Since alkali chlorides such as lithium chloride are very soluble, there was less lithium loss during neutralization than in the corresponding sulfate system.

We present a novel system for sketch-based face image editing, enabling users to edit images intuitively by sketching a few strokes on a region of interest. Our interface features tools to express a desired image manipulation by providing both geometry and color constraints as user-drawn strokes. As an alternative to the direct user input, our proposed system naturally supports a copy-paste mode, which allows users to edit a given image region by using parts of another exemplar image without the need of hand-drawn sketching at all. The proposed interface runs in real-time and facilitates an interactive and iterative workflow to quickly express the intended edits. Our system is based on a novel sketch domain and a convolutional neural network trained end-to-end to automatically learn to render image regions corresponding to the input strokes. To achieve high quality and semantically consistent results we train our neural network on two simultaneous tasks, namely image completion and image translation. To the best of our knowledge, we are the first to combine these two tasks in a unified framework for interactive image editing. Our results show that the proposed sketch domain, network architecture, and training procedure generalize well to real user input and enable high quality synthesis results without additional post-processing.

Sulfation roasting followed by water leaching process was used to extract lithium from lepidolite. Various parameters including roasting temperature, the amount of additions, and solid/liquid ratio in leaching process were optimized. The lithium extraction efficiency of 91.61% could be reached with a mass ratio of lepidolite/Na 2 SO 4 /K 2 SO 4 /CaO of 1:0.5:0.1:0.1, and roasting at 850 °C for 0.5 h. XRD analysis showed that sulfation roasting caused the decompositions of the original aluminosilicate to NaSi 3 AlO 8 , KAlSi 2 O 6 and CaAl 2 Si 2 O 8 . The phases of CaF 2 and Ca 4 Si 2 O 7 F 2 are observed due to the addition of CaO.

A novel technique was developed to extract lithium from lepidolite. The lepidolite was pre-roasted at a high temperature with water steam atmosphere for defluorination. Then the defluorinated lepidolite was leached in a lime–milk autoclave. Various parameters including the defluorination percentage of lepidolite, milling time, temperature, time, lime-to-defluorinated lepidolite ratio, and liquid-to-solid ratio in the leaching process were optimized. The lithium extraction efficiency can reach 98.9% under the optimal conditions. The purity of the lithium carbonate obtained can be up to 99.9%.

The effect of pre-roasting on leaching of the gamierite laterite ore, obtained from Yunnan province, China, was investigated in this study. The phase transformation of laterite minerals roasted at different temperatures was investigated with X-ray powder diffraction (XRD). The roasting experiment results show that there are two phase transformation processes of dehydroxylation of goethite and lizardite at roasting temperatures of 277 °C and 610 °C, respectively, which accord with the result of DTA–TG analysis. Pre-roasting of the laterite not only alters its mineralogical composition but also increases its porosity and surface area, thus making it more amenable to leaching. Compared to the leaching result of raw ore and ores roasted at different temperatures, it indicates that increasing roasting temperature up to 300 °C appears to provide the optimum nickel recovery and further heating appears to be detrimental to the nickel recovery.

In spent battery material, there are plenty of valuable metals, such as copper, nickel, cobalt, manganese. Recovery of valuable metals from spent battery material not only protects the environment but also improves the utilization of resources and decreases the cost of battery material. In this study, hydrochloric acid is used as lixivant with characteristics of faster leaching rate and being recycled easily. The optimal conditions are that hydrochloric acid concentration is 6 mol/L, reaction temperature is exactly 60 °C, liquid/solid ratio is 8:1, (H2O2)mol/(MeS)mol = 2, and the leaching time is 2 h, the results show that the dissolution yields of Ni, Co and Mn can be 95 wt.% at least. The basic purification concept of the leaching solution includes that copper is removed through replacement by iron powder followed by iron precipitation in goethite method. The results show that Cu and Fe can be removed 99 wt.% at the least. At the same time, the loss of Ni, Co and Mn is not beyond 2 wt.%, 3 wt.％ and 2 wt.%, respectively. This method makes the preparation of pure NixCoyMnz ternary system precursor economical. The process seems to be able to claim base metals from waste in a reliable and feasible way.

The monoclinic-type Li 3 V 2 (PO 4 ) 3 cathode material was synthesized via calcining amorphous Li 3 V 2 (PO 4 ) 3 obtained by chemical reduction and lithiation of V 2 O 5 using oxalic acid as reducer and lithium carbonate as lithium source in alcohol solution. The amorphous Li 3 V 2 (PO 4 ) 3 precursor was characterized by using TG–DSC and XPS. The results showed that the V 5+ was reduced to V 3+ by oxalic acid at ambient temperature and pressure. The prepared Li 3 V 2 (PO 4 ) 3 was characterized by XRD and SEM. The results indicated the Li 3 V 2 (PO 4 ) 3 powder had good crystallinity and mesoporous morphology with an average diameter of about 30 nm. The pure Li 3 V 2 (PO 4 ) 3 exhibits a stable discharge capacity of 130.08 mAh g −1 at 0.1 C (14 mA g −1 ).

LiFePO4/C composite cathode material was prepared by carbothermal reduction method, which uses NH4H2PO4, Li2CO3 and cheap Fe2O3 as starting materials, acetylene black and glucose as carbon sources. The precursor of LiFePO4/C was characterized by differential thermal analysis and thermogravimetry. X-ray diffraction (XRD), scanning electron microscopy (SEM) micrographs showed that the LiFePO4/C is olivine-type phase, and the addition of the carbon reduced the LiFePO4 grain size. The carbon is dispersed between the grains, ensuring a good electronic contact. The products sintered at 700 °C for 8 h with glucose as carbon source possessed excellent electrochemical performance. The synthesized LiFePO4 composites showed a high electrochemical capacity of 159.3 mAh g−1 at 0.1 C rate, and the capacity fading is only 2.2% after 30 cycles.