Synthesis of LiNi0.85Co0.14Al0.01O2 Cathode Material and its Performance in an NCA/Graphite Full-Battery

Nickel-rich cathode material, NCA (85:14:1), is successfully synthesized using two different, simple and economical batch methods, i.e., hydroxide co-precipitation (NCA-CP) and the hydroxides solid state reaction method (NCA-SS), followed by heat treatments. Based on the FTIR spectra, all precursor samples exhibit two functional groups of hydroxide and carbonate. The XRD patterns of NCA-CP and NCA-SS show a hexagonal layered structure (space group: R_3m), with no impurities detected. Based on the SEM images, the micro-sized particles exhibit a sphere-like shape with aggregates. The electrochemical performances of the samples were tested in a 18650-type full-cell battery using artificial graphite as the counter anode at the voltage range of 2.7–4.25 V. All samples have similar characteristics and electrochemical performances that are comparable to the commercial NCA battery, despite going through different synthesis routes. In conclusion, the overall results are considered good and have the potential to be adapted for commercialization.

Enhancing the Thermal and Upper Voltage Performance of Ni-Rich Cathode Material by a Homogeneous and Facile Coating Method: Spray-Drying Coating with Nano-Al2O3

The electrochemical performance of Ni-rich cathode material at high temperature (>50 °C) and upper voltage operation (>4.3 V) is a challenge for next-generation lithium-ion batteries (LIBs) because of the rapid capacity degradation over cycling. Here we report improved performance of LiNi0.8Co0.15Al0.05O2 materials via a LiAlO2 coating, which was prepared from a Ni0.80Co0.15Al0.05(OH)2 precursor by spray-drying coating with nano-Al2O3. Investigations by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy revealed that an Al2O3 layer is uniformly distributed on the precursor and a LiAlO2 layer on the as-prepared cathode material. Such a coating shell acts as a scavenger to protect the cathode material from attack by HF and serious side reactions, which remarkably enhances the cycle performance at 55 °C and upper operating voltage (4.4 and 4.5 V). In particular, the sample with a 2% Al2O3 coating shows capacity retentions of 90.40%, 85.14%, 87.85%, and 81.1% after 150 cycles at a rate of 1.0C at room temperature, 55 °C, 4.4 V, and 4.5 V, respectively, which are significantly higher than those of the pristine one. This is mainly due to the significant improvement of the structural stability led by the effective coating technique, which could be extended to other cathode materials to obtain LIBs with enhanced safety and excellent cycling stability.

Application of the central composite design to optimize the calcium carbonate-HPMC co-processed excipient prepared by co-spray drying

The central composite design-response surface methodology provided theoretical guidance for development of co-processed excipients based on calcium carbonate and HPMC.

Preparation and characterization of layered LiNi0.9Co0.05Mn0.025Mg0.025O2 cathode material by a sol–gel method for lithium-ion batteries

LiNi_0.9Co_0.05Mn_0.025Mg_0.025O₂ prepared by sol–gel method using citric acid had a well ordered hexagonal layered structure and showed excellent electrochemical performance.