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Lithium sulfonyl silica (LSS) was synthesized by replacing the surface H group in fumed silica with (CH 2 ) 3 SO 3 Li and adopted as electrolyte additive for lithium ion battery. 3 wt% of the synthesized particles in 1 M LiPF 6 (EC/DMC = 1:1) showed improved ionic conductivity and better potential stability over the pristine electrolyte. The discharge capacity of the LiCoO 2 /graphite is particularly enhanced with the addition of LSS at higher C-rates due to the enhanced ionic conductivity at room temperature. The LiCoO 2 /graphite cells using 1.0 M LiPF 6 /EC/DMC (1: 1) and 1.0 M LiTFSI/EC/DMC (1: 1) with LSS also showed superior performance for the self-discharge test carried out at 45 °C for 200 days. These positive impacts of LSS on LiCoO 2 /graphite cells warrant its use in lithium ion batteries. [ABSTRACT FROM AUTHOR]

Binary transition metal oxides have received extensive attraction as anode in lithium ion batteries because of their high theoretical capacities and synergistic effect of the two metal elements. In this work, CNTs embedded in Sb 2 MoO 6 @C hollow spheres are successfully fabricated through solvothermal process accompanied by sintering treatment. Benefiting from the hierarchical architecture and the conductive networks inside Sb 2 MoO 6 @C hollow spheres that induced by the CNTs and the amorphous carbon, the obtained CNTs@Sb 2 MoO 6 @C displays excellent high rate performance with a specific capacity of 219 mAh g−1 after 500 cycles at current density of 5000 mA g−1. • CNTs embedded in Sb 2 MoO 6 @C hollow spheres are successfully fabricated. • CNTs and the coated amorphous carbon networks facilitate Li+ ion diffusion. • CNTs@Sb 2 MoO 6 @C displays excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Fe 2 O 3 nano-particles and nano-rods were synthesized by hydrothermal synthesis method under different reaction conditions and then applied as anode materials for Lithium ion batteries. Microstructural analysis confirmed these two shapes and structures for Fe 2 O 3 samples. It was noticed that the electrochemical performance of Fe 2 O 3 is highly influenced by its particle morphology. Unexpectedly, Fe 2 O 3 nano-particles exhibit excellent electrochemical performances as compared to nano-rods morphology, which may be due to the least micro strain, high stability of nano-particles structure, small agglomerations, etc. It is believed that the nano-particles structure provides extra reaction sites to accommodate large Li-ions, shorten the Li-ion diffusion paths to improve the electronic conductivity and offers large electrolyte/electrode contact area for fast electrochemical reactions. In contrast, the nano-rods morphology could not hold its structural integrity during the lithiation/de-lithiation reactions and collapsed only after certain number of cycles giving rise to poor electrochemical performances, as confirmed by post cycling ex-situ studies. More precisely, Fe 2 O 3 nano-particles electrode delivered the excellent reversible capacity of 1125 mAh g−1 and 1007 mAh g−1 at 1C and 4C after 100 and 80 cycles, respectively, while Fe 2 O 3 nano-rods exhibit only 113.5 mAh g−1 at 1C and 326.7 mAh g−1 at 4C. • Fabrication of Fe 2 O 3 nano-particles and nano-rods morphology by hydrothermal synthesis method. • Fe 2 O 3 nano-particles retained its morphology while nano-rod morphology collapsed during cycling. • Nano-particles morphology buffered volume expansion/contraction of electrode during cycling. • Fe 2 O 3 nano-particles exhibits superior electrochemical performances than nano-rods electrode. [ABSTRACT FROM AUTHOR]

We report a unique N/O co -doped urchin-like carbon microspheres (UCMSs) via facile pyrolysis process based on urchin-like polyaniline microspheres (UPMSs) as precursor. UPMSs are obtained through simple self-assembled method without any aided reagent, so the total preparation process of UCMSs is very easy and repeatable. Among three samples, UCMSs-600 shows high lithium storage capacity at 50 mA g−1 (952 mAh g−1) and UCMSs-700 possesses relatively good rate and cycling performance (only 0.026% of attenuation in every cycle at 0.5 A g−1). The correlation between structural parameters (carbon interlayer distance, ordered degree, pore structure and heteroatom doping) and lithium storage features (reversible capacity, rate and cycling performance) of UCMSs with different carbonization temperatures are discussed in detail. And we can obtain the conclusion that designing carbon materials with unique spherical structure and heteroatom-doped feature is a very efficient approach to obtain advanced lithium ion batteries. Unlabelled Image • Polyaniline-based N/O co-doped urchin-like carbon microspheres (UCMSs) were prepared. • The correlation between structure and lithium storage capacity of UCMSs was studied. • Synthesis of N/O co-doped carbon spheres is an effective way to get advanced anodes. [ABSTRACT FROM AUTHOR]

High capacity lithium-rich layered oxide Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 cathode material is considered as a most promising cathode material for lithium ion batteries. However, its application is greatly limited due to the characteristics of low initial coulombic efficiency and poor low-temperature performance. In this study, AlF 3 -coated Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 has been prepared via a facile wet chemical process. It is found that a dense AlF 3 layer with a nanoscale thickness is covered on the surface of Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 particles, building a rapid lithium transport bridge for adjacent active materials and reducing side reaction between the electrolyte and active material. Compared to the pristine Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 , 2% AlF 3 -coated sample exhibits higher discharge capacity and initial coulombic efficiency (86.7%). Meanwhile, 2% AlF 3 -coated sample displays obviously superior rate capability at 0 °C and higher capacity retention at −10 and −20 °C. The improvement of low-temperature performance can reasonably be attributed to the formation of the spinel structure and the LiAlO 2 on the surface of the active materials, which can improve the electronic conductivity and lithium ion conductivity of the cathode material, respectively. Unlabelled Image • AlF 3 is coated on Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 to improve low-temperature performance. • AlF 3 layer builds a rapid lithium transport bridge and reduces side reaction. • An enhanced initial Coulombic efficiency (86.7%) is obtained for AlF 3 coated sample. • Two times capacity increase is delivered at −20 °C for the 2% AlF 3 -coated sample. • Spinel structure and LiAlO 2 phase improve the electronic and Li+ conductivity. [ABSTRACT FROM AUTHOR]

Novel NASICON-type structural Li 1.3 Al 0.3 Ti 1.7 Si x P 5(3-0.8x) O 12 (LATSP) solid electrolytes are synthesized by spray-drying combined with sintering methods, and the corresponding physicochemical properties are investigated by X-ray diffraction, Field emission scanning electron microscope, Fourier transform infrared spectrometer and X-ray photoelectron spectroscopy. The targeted LATSP powders present uniform cube-like morphology and excellent crystallinity, in which the LATSP-0.05 solid electrolyte exhibits a high ionic conductivity of 1.053 E-4 S cm−1 and a low activation energy of 0.44 eV at 25 °C as well as a high compaction density of 2.892 g cm−3 when the content of Si doping retains 5% vs. the molar ratio of the pure Li 1.3 Al 0.3 Ti 1.7 (PO 4) 3. Furthermore, the assembled LiCoO 2 /LATSP-0.05/Li all-solid-state coin cell can achieve a relatively high initial discharge specific capacity of 116.2 mAh g−1 at 0.1 C and possess outstanding cycle and rate performance compared to other cells at room temperature. These results show that the novel LATSP-0.05 solid electrolyte with NASICON-type structure is expected to widely employ in the field of all-solid-state lithium ion batteries. Preparation schemes of novel NASICON-type structural Li 1.3 Al 0.3 Ti 1.7 Si x P 5(3-0.8x) O 12 solid electrolytes. Unlabelled Image • NASICON-type structural Li 1.3 Al 0.3 Ti 1.7 Si x P 5(3-0.8x) O 12 solid electrolytes are synthesized. • The LATSP-0.05 exhibits uniform morphology and excellent crystallinity. • Ionic conductivity and activation energy are 0.105 mS cm−1 and 0.44 eV, respectively. • The assembled all-solid-state cell presents outstanding cycle and rate performance. [ABSTRACT FROM AUTHOR]

N-doped biomass-derived porous carbon (N/C) with a 3D framework and large specific surface area was obtained by carbonizing bagasse biomass waste with melamine as nitrogen source. The obtained N/C has macroporous structures, rich mesoporous and microporous structures. The multi-grade pore structure can not only increase the specific surface area, but also effectively provide multi-layer electron transmission channels. N-doping can greatly enhance the interaction between anchor sites and lithium ions, because it can alter local electron density, which is conducive to lithium-ion adsorption and anchoring. As anode of lithium ion batteries (LIBs), it exhibits excellent reversible specific capacity of 530 mAh g−1 at 0.1 A g−1 after 100 cycles. Furthermore, this study demonstrates the employment of natural waste material as a potential anode for LIBs, which will definitively make a strike in the energy storage field. Unlabelled Image • N-doped biomass-derived porous carbon (N/C) was obtained by carbonizing bagasse biomass waste with melamine as nitrogen source. • The N/C was used as anode material for lithium ion batteries. • The N/C exhibits excellent reversible specific capacity of 530 mAh g−1 [ABSTRACT FROM AUTHOR]

Recently, ternary synergetic-system cathode materials have been recognized as effective kinetic processes for improving the performance of lithium-ion batteries. Here, novel one-dimensional carbon/MoO 2 @MoS 2 ternary synergetic-system heterostructures are successfully synthesized by constructing MoO 2 @MoS 2 heterojunction structures onto electrospun carbon fibers. The effective self-built electric fields in MoO 2 @MoS 2 heterojunction interfaces and high conductive performance of carbon fibers insure high reversible specific capacity (1052.4 mAh/g at 500 mA/g) and high rate performance (670 mAh/g at 10 A/g) as anodes in lithium ion batteries. Finally, the mechanism of this ternary synergetic system for enhancement of electrochemical performance is discussed in detail, based on effective self-built electric fields caused by different band energies between MoO 2 and MoS 2. Unlabelled Image • Carbon/MoO 2 @MoS 2 ternary synergetic systems have been synthesized. • The composites exhibit high specific capacitance and rate performance. • An effective self-built electric fields is formed between MoO 2 and MoS 2 interface. • The synergistic effect results in excellent electrochemical performances. [ABSTRACT FROM AUTHOR]