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• Concentration gradient material is successfully synthesized detected by line scan. • XRD tests show that the samples doped with Mn have better layered structure. • TEM images show that the samples doped with Mn have more obvious lattice fringes. • After 200 cycles at 1 C, the capacity retention rate of G-LNM91 remains 87.5%. The cathodes of LiNiO 2 (LNO), Li[Ni 0.9 Mn 0.1 ]O 2 (LNM91) and the concentration gradient material Li[Ni 0.9 Mn 0.1 ]O 2 (G-LNM91) were synthesized by co-precipitation method, and SEM, XRD, TEM and electrochemical tests were performed. SEM images show that the primary needle-like particles on spherical surface of the gradient G-LNM91 are the densest. The results of EDX linear scan show that for gradient precursor G-NM91, the relative atomic content of Ni element gradually decreases from 98.21% at the center of the particle to 80.66% at the cross surface of the particle (the content of Mn from 1.79% gradually increases to 19.34%). For the final product G-LNM91, the relative atomic content of Ni element in the center decreases to 94.07%, and at the edge increases to 85.17%. XRD tests indicate that the samples doped with Mn have good layered structure. TEM images show that the lattice fringes of the samples doped with Mn are more obvious. The results of Electrochemical performance tests show that manganese substitution has a significant effect on improving the cycle performance of LiNiO 2 , and G-LNM91 has the best cycle performance. Under a voltage range of 2.75–4.3 V, the initial discharge capacity of G-LNM91 cathode material at 0.1 C is 200 mA h/g. After 200 cycles at 1 C, the capacity retention rate remains around 87.5%. The initial discharge capacity of LNM91 is 180 mA h/g and the retention rate is 78.5%; the capacity retention rate of LiNiO 2 is only 55.2%, even though the initial specific discharge capacity is 207 mA h/g. [ABSTRACT FROM AUTHOR]

La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ (LSCF) is a promising cathode material for solid oxide fuel cells (SOFCs). Hence, structured LSCF coatings were deposited in this study by atmospheric laminar plasma spraying (ALPS) at the spraying distances from 150 mm to 250 mm. Particles with high temperature were obtained at low plasma arc power of only 15 kW. The microstructural characterization of the coatings showed cluster-like morphologies on the top surfaces and columnar features with large-scale vertical cracks at the cross section. An evolution mechanism of the coatings was proposed based on particle size. The movement of particles during laminar plasma jet depended on particle size, which was studied experimentally and by simulation to explain the selective deposition. The coatings showed lower polarization resistance when compared to LSCF coatings deposited by atmospheric plasma spraying (APS) due to large vertical crack densities. The high output performance of the SOFCs with the LSCF cathode also proved this phenomenon. The results suggest that ALPS provides extensive options for SOFCs manufacturing. • LSCF coatings were deposited at the long spraying distances, although at low plasma arc power of only 15 kW. • The selective deposition depended on particle size was proposed to explain various structures of coatings. • Structured coatings with large-scale vertical cracks revealed lower polarization resistances compared to APS coatings. [ABSTRACT FROM AUTHOR]