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Enhancement of the discharge capacity, high-rate capability, and cycle stability of the Li-rich layered Li(Li 0.17 Ni 0.25 Mn 0.58 )O 2 oxide with a large specific capacity is highly significant for high energy lithiumion batteries. In this work, the Li-rich layered Li(Li 0.17 Ni 0.25 Mn 0.58 )O 2 oxide is prepared by a spray-drying method. The surface modification with the Li-Mn-PO 4 is introduced onto Li-rich layered Li(Li 0.17 Ni 0.25 Mn 0.58 )O 2 oxide for the first time. It is demonstrated that the surface of Li(Li 0.17 Ni 0.25 Mn 0.58 ) O 2 grains is coated with the thin amorphous Li-Mn-PO 4 layer (5 wt%). With increasing calcination temperature after the surface coating, a strong interaction can be induced on the interface between the amorphous Li-Mn-PO 4 layer and the top surface of Li(Li 0.17 Ni 0.25 Mn 0.58 )O 2 grains. As anticipated, the discharge capacity and high-rate capability are obviously improved for the Li-Mn-PO 4 -coated sample after calcination at 400 C, while excellent cycle stability is obtained for the Li-Mn-PO 4 -coated sample after calcination at 500 C as compared with the as-prepared Li(Li 0.17 Ni 0.25 Mn 0.58 )O 2 oxide during cycling. Apparently, the interface interaction between the amorphous Li-Mn-PO 4 layer and the top surface of Li(Li 0.17 Ni 0.25 Mn 0.58 )O 2 grains is responsible for the improvement of the reaction kinetics and the electrochemical cycle stability of Li-Mn-PO 4 -coated samples.

Sulfur–carbon composites were prepared by an in situ sulfur deposition route developed for the heterogeneous nucleation of sulfur into nanopores of conductive carbon black (CCB) by fumigation of Na2S4/CCB powder with HCl. The sulfur–carbon composites demonstrate enhanced reversible capacity and stable cycle performance.