Lithium Diffusion and Diffraction

In the current contribution the application of bond valence method for the prediction (and diffraction-based techniques for the evalution) of ion diffusion pathways in different materials for electrochemical energy conversion and storage will be presented and discussed

Homogeneity of lithium distribution in cylinder-type Li-ion batteries

Spatially-resolved neutron powder diffraction with a gauge volume of 2 × 2 × 20 mm$^{3}$ has been applied as an in situ method to probe the lithium concentration in the graphite anode of different Li-ion cells of 18650-type in charged state. Structural studies performed in combination with electrochemical measurements and X-ray computed tomography under real cell operating conditions unambiguously revealed non-homogeneity of the lithium distribution in the graphite anode. Deviations from a homogeneous behaviour have been found in both radial and axial directions of 18650-type cells and were discussed in the frame of cell geometry and electrical connection of electrodes, which might play a crucial role in the homogeneity of the lithium distribution in the active materials within each electrode

Improved voltage and cycling for Li⁺ intercalation in high-capacity disordered oxyfluoride cathodes

New high-capacity intercalation cathodes of Li2VxCr1−xO2F with a stable disordered rock salt host framework allow a high operating voltage up to 3.5 V, good rate performance (960 Wh kg−1 at ≈1 C), and cycling stability

The Electrochemical Performance and Applications of Several Popular Lithium-ion Batteries for Electric Vehicles - A Review

The Lithium-ion battery is one of the most common batteries used in Electric Vehicles (EVs) due to the specific features of high energy density, power density, long life span and environment friendly. With the development of lithium-ion battery technology, different materials have been adopted in the design of the cathodes and anodes in order to gain a better performance. $LiMn_{2}O_{4}$ , $LiNiMnCoO_{2}$ , $LiNiCoAlO_{2}$ , $LiFePO_{4}$ and $Li_{4}Ti_{5}O_{12}$ are five common lithium-ion batteries adopted in commercial EVs nowadays. The characteristics of these five lithium-ion batteries are reviewed and compared in the aspects of electrochemical performance and their practical applications

A mechanochemical route to single phase Cu2ZnSnS4 powder

With respect to absorber materials in solar cells, Cu2ZnSnS4 CZTS has been a focus of interest in recent years. In this work, a new route leading to single phase CZTS powders is presented. For structural characterization X ray and neutron powder diffraction measurements were performed. Further structural and compositional analysis of the CZTS powder was carried out by means of X ray absorption near edge spectroscopy XANES and wavelength dispersive X ray spectroscopy WDS . The obtained CZTS powder with an actual composition of Cu2.00 4 Zn1.02 2 Sn0.99 2 S4.00 8 adopts the kesterite type structure. A detailed cation distribution analysis using the average neutron scattering length method revealed a partial disorder of copper and zinc on the 2c and 2d site

Lithium Diffusion and Diffraction

In the current contribution the application of bond valence method for the prediction (and diffraction-based techniques for the evalution) of ion diffusion pathways in different materials for electrochemical energy conversion and storage will be presented and discussed

Understanding structural changes in NMC Li-ion cells by in situ neutron diffraction

Commercial NMC cells of 18650-type based on a Lix(Ni0.5Mn0.3Co0.2)O2 cathode and a graphitic anode were studied in situ using a combination of high-resolution monochromatic neutron powder diffraction and electrochemical analysis. The structural changes of the electrode materials during cell charge/discharge have been determined using Rietveld refinement and single profile decomposition techniques. A transformation of the graphitic anode to LiC12 and LiC6 through the formation of higher ordered lithium intercalated carbons was observed. A different behavior of electrochemically-driven lattice distortion was observed for NMC material in comparison to LixCoO2 and its influence on the overall cell performance has been discussed in brief. Detailed analysis of the structural changes in the Lix(Ni0.5Mn0.3Co0.2)O2 cathode material revealed reversible Li/Ni cation mixing (5.6(8)%), which is state-of-charge independent below 1600 mAh and vanishing above 1800 mAh (∼0.8Qmax)