Nickel-rich layered lithium transition-metal oxides, LiNi(1-x)M(x)O(2) (M = transition metal), have been under intense investigation as high-energy cathode materials for rechargeable lithium batteries because of their high specific capacity and relatively low cost. However, the commercial deployment of nickel-rich oxides has been severely hindered by their intrinsic poor thermal stability at the fully charged state and insufficient cycle life, especially at elevated temperatures. Here, we report a nickel-rich lithium transition-metal oxide with a very high capacity (215 mA h g(-1)), where the nickel concentration decreases linearly whereas the manganese concentration increases linearly from the centre to the outer layer of each particle. Using this nano-functional full-gradient approach, we are able to harness the high energy density of the nickel-rich core and the high thermal stability and long life of the manganese-rich outer layers. Moreover, the micrometre-size secondary particles of this cathode material are composed of aligned needle-like nanosize primary particles, resulting in a high rate capability. The experimental results suggest that this nano-functional full-gradient cathode material is promising for applications that require high energy, long calendar life and excellent abuse tolerance such as electric vehicles.

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High-resolution X-ray computed tomography (XCT) enables nondestructive 3D imaging of complex structures, regardless of their state of crystallinity. This work describes a sub-50 nm resolution XCT system operating at 8 keV in absorption and Zernike phase contrast modes based on a commercially available Cu rotating anode laboratory X-ray source. The system utilizes a high efficiency reflective capillary condenser lens and high-resolution Fresnel zone plates with an outermost zone width of 35 nm and 700 nm structure height resulting in a spatial resolution better than 50 nm currently. Imaging a fragment of the solid oxide fuel cells (SOFC) with 50 nm resolution is presented as an application example of the XCT technique in materials science and nanotechnology.

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