Self-Polymerized Cr–Sr Co-Doped LiNi 0 . 5 Mn 1 . 5 O 4 : Synergistic Enhancement of Structural Stability and CV-Quantified Li + Diffusivity for 5 V Long-Cycle High-Rate Performance
Year: 2026
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide Cr–Sr codoped LiNi 0.5 Mn 1.5 O 4 (LNMO) cathode materials with different compositions, LiNi 0.5– x Cr x Sr y Mn 1.5– y O 4 ( x = 0,0.02; y = 0,0.03) were synthesized using a self-polymerization method. The materials were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and transmission electron microscopy (TEM) to investigate their structural properties. Electrochemical performance was evaluated through the initial charge–discharge capacity, rate capability, cycling discharge capacity, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) tests. The study provides an in-depth analysis of the effects of crystal structure, microstructure, and the distribution of doped elements on the rate performance and cycling stability of the Cr–Sr codoped LNMO samples during the charge–discharge process.The results revealed that the Cr–Sr codoped material LiNi 0.48 Cr 0.02 Mn 1.47 Sr 0.03 O 4 exhibited a disordered Fd3m space group, which reduced electrochemical polarization and charge transfer resistance. The material effectively suppressed the formation of the Li x Ni 1– x O impurity phase, ensuring product purity and structural stability. The crystal structure transitioned from spinel octahedral to truncated octahedral, promoting the exposure of {100} crystal planes, which facilitated the Li + diffusion rate and improved rate performance. Furthermore, the doping also reduced the Mn 3+ content on the crystal surface, avoiding the dissolution side reactions of manganese at the electrode–solution interface, thereby enhancing cycling capacity stability during charge–discharge processes. At 1C and 5C rates, the discharge capacities were 132 mAh/g and 127 mAh/g, respectively. After 200 cycles at 1C, the capacity remained at 121 mAh/g, with a capacity retention of 91.67%, indicating that Cr–Sr doping via the self-polymerization method significantly improves the electrochemical performance.
Source: ACS Omega
Authors: ZhenDe Huang, Di Peng
Institution: Guangxi Vocational & Technical Institute of Industry
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,935
Awards: G5719574594, G9000278095
OpenAlex ID: W7148580966