Self-assembled porous LiNi0.8Co0.1Mn0.1O2 cathode materials with micro/nano-layered hollow morphologies for high-power lithium-ion batteries

In this article, for the first time, we employ the solvo/hydrothermal method as a versatile and straightforward strategy through using organic solvent ethylene glycol (EG) instead of part of deionized water and adding polyvinylpyrrolidone (PVP) as a surfactant to synthesize micro/nano-layered structure materials. • The porous LiNi 0.8 Co 0.1 Mn 0.1 O 2 material was synthesized by using hydrothermal method through adding ethylene glycol and polyvinylpyrrolidon. • The spherical-like hollow material is self-assembled from nanoblock primary particles into secondary micro-architectures. • The addition of EG and PVP not only expands the electrochemical active region of LiNi 0.8 Co 0.1 Mn 0.1 O 2 material, but also inhibits the Ni 2+ /Li + disorder and the pulverization. • The LiNi 0.8 Co 0.1 Mn 0.1 O 2 material after adding EG and PVP retains the highest discharge capacity of 220.18 mAh g −1 for the initial circle and the capacity retention rate of the cathode material is 82.36% at 20 mA g −1 after 100 cycles. The Ni 2+ /Li + disorder has become one of the core problems limiting the application of LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode material. Herein, an ammonium bicarbonate (NH 4 HCO 3 )-assisted solvo/hydrothermal method has been effectively applied to synthesize a novel hollow porous LiNi 0.8 Co 0.1 Mn 0.1 O 2 material through adding ethylene glycol (EG) and surfactant polyvinylpyrrolidone (PVP) for the first time in this paper. The obtained cathode materials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). The as-prepared material with unique spherical-like hollow structure is self-assembled from nanoblock primary particles into secondary micro-architectures. The results indicate that the addition of EG and PVP not only expands the electrochemical active region of LiNi 0.8 Co 0.1 Mn 0.1 O 2 material, but also inhibits the Ni 2+ /Li + disorder and the pulverization of the as-prepared sample. The practical application indicates that the material after adding EG and PVP delivers the highest discharge capacity of 220.18 mAh g −1 for the initial circle, and the capacity retention rate of the spherical-like cathode material is 82.36% at 20 mA g −1 after 100 cycles. In particular, this unique micro/nano-layered architecture effectively withstands high-rate charging and discharging process and maintains the integrity of the original structure after fast Li + extraction and diffusion.