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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]

A novel molecular model of carbonyl-substituted phthalocyanine compounds used as the cathode material in a lithium-ion battery is demonstrated. Tetra-carboxyl and octa-carboxyl groups are substituted onto a phthalocyanine-conjugated system. The conductivities of phthalocyanine compounds are effectively improved by I doping, without affecting the capacity and energy density. Taking lithium as the counter-electrode, the electrochemical properties of the microparticles are investigated, and the electrochemical mechanism of carboxyl groups substituted with phthalocyanines is analyzed. The results indicate that carboxyl-substituted phthalocyanines have high specific capacities. After 20 or 50 cycles, they still retain capacities of about 300 and 500 mA · h/g for tetra-carboxyl- and octa-carboxyl-substituted phthalocyanines, respectively. The multiple carbonyl groups and the large numbers of electrons on the phthalocyanine-conjugated system are the two factors contributing to the high specific capacity. [ABSTRACT FROM AUTHOR]

Cubic perovskite–type oxide Li 3/8 Sr 7/16 Hf 1/4 Ta 3/4 O 3 (LSHT) is a promising solid electrolyte material for next–generation Li–ion batteries such as all–solid–state Li batteries and Li–redox flow batteries due to its high room–temperature Li–ion conductivity and good chemical compatibility with commercial organic liquid electrolyte. High relative density is another important requirement for these applications. Here we investigate the influence of sintering additives (Li 3 BO 3 , Li 4 SiO 4 , LiF) on the density, the total Li–ion conductivity, the interfacial conductivity against commercial liquid electrolyte, and the cycling performance of the hybrid Li-ion cells. The results show that comparing with other additives, LSHT sintered with 2 wt% LiF shows the highest Li–ion conductivity (3.3 × 10 −4 S cm −1 ) and the smallest interfacial resistance (125 Ω cm 2 ) against organic electrolyte at room temperature; Li/LiFePO 4 batteries with LSHT pellets fired with 2 wt% LiF have the best cyclability and the highest coulombic efficiency (99.6 ± 0.04%) in 50 cycles. [ABSTRACT FROM AUTHOR]

Highlights: [•] LNMO and LANMO hollow microspheres are synthesized by template method. [•] The as-synthesized hollow microspheres have particle-size of 2μm. [•] The hollow structure is responsible for improved electrochemical performance. [ABSTRACT FROM AUTHOR]