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To suppress capacity fading of nickel-rich materials for lithium-ion batteries, a homogeneous Al3+ doping strategy is realized through tailoring the Al3+ diffusion path from the bulk surface to interior. Specifically, the layered LiNi0.88Co0.095Mn0.025O2 cathode with the radial arrangement of primary grains is successfully synthesized through optimization design of precursors. The Al3+ follows the radially oriented primary grains into the bulk by introduction of nano-Al2O3 during the sintering process, realizing the homogeneous Al3+ distribution in the whole material. Particularly, a series of nano-Al2O3-modified LiNi0.88Co0.095Mn0.025O2 are investigated. With the 2% molar weight of Al3+ doping, the capacity retention ratio of the cathode is tremendously improved from 52.26 to 91.57% at 1 C rate after 150 cycles. Even at a heavy current density of 5 (&10) C for the LiNi0.88Co0.095Mn0.025O2–Al2% cathode, a high reversible capacity of 172.3 (&165.7) mA h g–1 can be acquired, which amount to the 84.46 (&81.25) % capacity retention at 0.2 C. Moreover, voltage deterioration is significantly suppressed by homogeneous Al3+ doping from the results of median voltage and dQ/dV curves. Therefore, homogeneous Al3+ doping benefited from the radial arrangement of primary grains provides an effective and practical way to prolong lifespan, as well as improves rate performance and voltage stability of nickel-rich ternary materials.

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Lithium metal anodes are considered to be the most promising anode material for next-generation advanced energy storage devices due to their high reversible capacity and extremely low anode potential. Nevertheless, the formation of dendritic Li, induced by the repeated breaking and repairing of solid electrolyte interphase layers, always causes poor cycling performance and low coulombic efficiency, as well as serious safety problems, which have hindered the practical application of Li anodes for a long time. Herein, we design an electrode by covering a polyvinyl alcohol layer with a three-dimensional nanofiber network structure through an electrospinning technique. The polar functional groups on the surface of the polymer nanofibers can restrict the deposition of Li along the fibers and regulate the deposition of Li uniformly in the voids between the nanofibers. Owing to the structural features of the polymer, the modified Li|Cu electrode displays excellent cycle stability, with a high coulombic efficiency of 98.6% after 200 cycles at a current density of 1 mA cm-2 under a deposition capacity of 1 mA h cm-2, whilst the symmetric cell using the polymer modified Li anode shows stable cycling with a low hysteresis voltage of ∼80 mV over 600 h at a current density of 5 mA cm-2.