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As the research on lithium‐ion battery cathode materials gradually breaks through the saturation, the anode materials for lithium‐ion batteries have received wide attention because of their promising future. Silicon electrodes, in particular, are attracting increasing attention. In this paper, the Si/G precursor was achieved by simple mechanical ball milling. Two silicon based composite electrode materials Si@TA and Si@TA‐G were synthesized by spontaneous polymerization of tannic acid on precursor surface in Tris buffer solution. For the poor electrical conductivity of silicon, graphite was added as a carbon source to avoid the direct contact between silicon and electrolyte during charge/discharge process by forming tannic acid coating on silicon surface.The Si@TA composites achieve a discharge specific capacity of 927.4 mAh g−1 at 100 mA g−1 current density after 50 cycles with a retention rate of 87.1 % while the reversible capacity of Si@TA‐G is 1249.8 mAh g−1 with a retention rate is 93.6 %. This unique composite method provides new insights into the modification of silicon anode materials. [ABSTRACT FROM AUTHOR]

Traditional polyolefin separators suffer from poor heat resistance and wettability with electrolyte, which leads to compromised safety and electrical properties of lithium‐ion batteries. Polyvinylidene fluoride (PVDF) has high thermal stability and good chemical stability, but its high crystallinity leads to low ionic conductivity. In order to solve these problems, polyvinyl alcohol (PVA) resin was introduced in this paper, and the PVDF/PVA composite separator was prepared by double‐needle electrospinning. The introduction of PVA resin improved its mechanical properties and electrolyte wettability, and ionic conductivity after assembly into a battery. Double‐needle electrospinning process is simple and can preserve the surface properties of fibers, and the prepared composite separator had a high porosity and electrolyte uptake. The composite separator has an ionic conductivity of 2.454 mS ⋅ cm−1, a high capacity retention rate of 97.5 % after 100 charge and discharge cycles, and a capacity retention rate of 86.8 % under 2 C high‐rate discharge. The results show that the battery assembled with PVDF/PVA composite separator has high safety performance and electrical performance, and has application prospects. [ABSTRACT FROM AUTHOR]

Transition‐Metal chalcogenides have high Li‐ion storage capacity and considerable cycle performance, which has attracted great interest from researchers and is expected to replace graphite materials in the field of Li ion batteries. The purpose of this paper is to find a low‐cost and ecofriendly method for producing copper‐based chalcogenides as anodes with a high capacity and long cycling stability for lithium ion batteries. In our strategy, carbon nanospheres are used as templates to prepare precursor Cu(OH)2@C. Then, the Cu(OH)2@C is converted into copper‐based chalcogenides by different routes. The structure and morphology of the as‐synthesized materials is characterized by the X‐ray diffraction, scanning electron microscopy and transmission electron microscopy. The anode electrochemical performance of the samples was investigated by galvanostatic cycling (GC) vs. Li/Li+ at different current rate. Compared to other copper chalcogenides, the synthesized copper oxide shows better charge/discharge cycle stability and rate performance. Its capacity retention is as high as 128 % at a current density of 0.5 C after 200 cycles. [ABSTRACT FROM AUTHOR]

In order to satisfy the growing energy demand of large‐scale applications such as energy storage for renewable sources and for electromobility, advanced electroactive materials are required for energy storage technologies. The aim of this work is to develop a new cathode concept for Li‐ion batteries, which allows high charging/discharging rates as well as high gravimetric capacities. The composite cathode consisting of LiFePO4 (high rates) and S (high capacity), takes advantage of the benefits of both materials. However, it is a challenge considering the reactivity of both materials, and the electrolytes needed for each of them. This paper deals with some strategies to make the composite work; the problems encountered when having two materials with different electrochemical behavior in the same electrode in a battery have been partially solved. The voltammetric studies of this work show promising results for the development of the new concept of lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

SnO2 is known as a promising anode candidate for lithium‐ion batteries (LIBs), but suffers from the low electrical conductivity and severe volume variation during cycling, which restraint its practical applications. To solve these issues, we successfully fabricated the three‐dimensional structure of carbon obtained from corn stalks and SnO2 composites. The materials exhibit excellent electrochemical performance. After 100 cycles, it shows a reversible capacity of 691 mA h g−1 at a current density of 0.2 C. Excellent cycle performance is due to the unique structure, which has a strong internal chemical bond between the SnO2 nanoparticles (SnO2 NPs) and the carbon skeleton, preventing SnO2 NPs from falling off the 3D network during the cycle. This work may provide a broader vision into synthesising C‐SnO2 composites for high‐performance anode materials of LIBs. In this paper, we successfully fabricated the three‐dimensional structure of carbon obtained from corn stalks and SnO2 composites by a simple one‐step hydrothermal method. The materials exhibit excellent electrochemical performance. After 100 cycles, it shows a reversible capacity of 691 mA h g−1 at a current density of 0.2 C. Its electrochemical performance is much higher than the SnO2 used in the market. [ABSTRACT FROM AUTHOR]