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Carbonyl rich conjugated polymer electrode materials for lithium‐ion batteries possessed the advantages of strong molecular design ability, abundance and high theoretical capacity. In this work, a Co2+ coordinated conjugated polymer using 2,3,5,6‐tetraamino‐p‐benzoquinone (TABQ) as building block was constructed and developed as electrode material for all organic symmetric lithium‐ion batteries, outputting a specific capacity of over 100 mAh g−1 after 50 cycles at 50 mA g−1. Performances of Co‐TABQ in half cells were explored. The Co‐TABQ cathode delivered a capacity of 133.3 mAh g−1 after 150 cycles at 20 mA g−1. When cycled at higher current density of 500 mA g−1, the capacity gradually increased to 109.4 mAh g−1 after 4000 cycles. The Co‐TABQ anode displayed a stable capacity of 568.6 mAh g−1 at 1 A g−1. The charge transfer within the electrode was greatly reduced due to the metallic centers in the extended conjugated skeleton, and the reversible Li+ storage was achieved by the active C=O and imine groups. This work showed the great potential of metal mediated conjugated polymer in Lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Transition metal oxides as anode materials for lithium‐ion batteries (LIBs) possess the advantages of high specific capacity and abundance. However, most reported transition metal oxides based active anode materials were coated on the copper current collector with the addition of inactive polymer binder and conductive agents, resulting in low utilization of active substances. To solve this problem, nanostructured CuO with different morphologies (CuO bunches, CuO nanosheets, CuO nanotubes) were in‐situ grown on the copper current collectors via a simple wet chemical oxidation method. The as‐obtained CuO@Cu foils were used directly as anode for LIBs. CuO nanotubes exhibited excellent electrochemical performance and sustained a reversible discharge specific capacity of 798 mA h g−1 after 60 cycles at 100 mA g−1. At current density of 1000 mA g−1, a high specific capacity of 758 mA h g−1 can be obtained after 200 cycles. The satisfying electrochemical performances of the CuO nanotubes anode indicated that a stable composite structure of CuO@Cu foils was achieved in the binder free electrode. This work demonstrated the feasibility of this binder free strategy in the development of electrode materials for high performance lithium‐ion batteries design. [ABSTRACT FROM AUTHOR]

Ultrathin all‐solid‐state electrolytes with an excellent Li+ transport behavior are highly desirable for developing high‐energy‐density solid‐state lithium metal batteries. However, how to balance the electrochemical performance and their mechanical properties remains a huge challenge. Herein, an ultrathin solid electrolyte membrane with a thickness of only 3 µm and a weight of 11.7 g m−2 is well constructed by integrating individual functionalized organic with inorganic modules. Impressively, the optimized hybrid electrolyte membrane shows a set of merits including a high room‐temperature ionic conductivity of 1.77 × 10−4 S cm−1, large Li+ transference number of 0.65, and strong mechanical strength (strength of 29 MPa, elongation of 95%), as well as negligible thermal shrink at 180 °C. The analysis results reveal that the lithium sulfonate‐functionalized mesoporous silica nanoparticles in the membrane play a crucial role in the selective transport of Li+ through anion trapping and cation exchange. The pouch full cell is further assembled with a high‐voltage NCM cathode and thin lithium anode, which exhibits excellent long‐term cycling stability, outstanding rate performance at room temperature, and high safety against abused conditions. The current work provides an innovative strategy for achieving lithium metal batteries with ultrathin all‐solid‐state electrolytes. [ABSTRACT FROM AUTHOR]

In a wireless communication system, the radio propagation channel is a complicated component to characterise. Channel sounding equipment thus has to meet specific criteria to extract the desired channel parameters. In this study, the authors outline the development and validation of a vector network analyser (VNA) based channel sounder for the frequency range from 1 to 50 GHz using radio‐over‐fibre techniques. Three methods of de‐embedding phase errors due to hardware impairments are demonstrated and validated via back‐to‐back measurements. The bidirectional scheme utilising optical circulators is shown to have a superior performance over the two‐branch unidirectional and the two‐branch bidirectional schemes. Therefore, the bidirectional scheme utilising optical circulators is proposed to achieve a long‐range ultra‐channel sounder based on the VNA. [ABSTRACT FROM AUTHOR]