| Lithium-ion battery has drawn great attention due to its high voltage, high energy density, long cycle life, low self-discharge, non-memory effect and environmental friendliness. Most commercialized lithium-ion batteries consist of cathode material LiCoO2 and organic liquid electrolyte, which results in high cost and some safe problems. To seek inexpensive cathode materials and get rid of safe problems by using solid electrolyte become the hot points of the researches on lithium-ion batteries. As one kind of solid-state lithium-ion batteries, thin-film lithium-ion battery has many applications, such as smart cards, COMS-based integrated circuit and micro-devices, and as a result, has become one of the most studied branches of lithium-ion batteries.According to the development tendency of lithium-ion and thin-film lithium-ion batteries, we focus our studies on the synthesis and characterization of a promising cathode material LiMn2O4 and solid electrolyte Li1.3Al0.3Ti1.7(PO4)3 that possesses high ionic conductivity together with a wide electrochemical window.LiMn2O4 powders were prepared by heating the ignited LiMn2O4 precursor gel using lithium acetate, magnesium acetate, citric acid and glycol as starting materials. The influence of annealing temperature, annealing time on the structural and electrochemical properties of LiMn2O4 powder was investigated, and A. C. impedance of LiMn2O4 electrode was studied. The powders prepared under different conditions are of good crystallinity. The particle size, lattice parameter and the first discharge capacity of LiMn2O4 powder increase with the increase of annealing temperature or time. The cycling behavior of the powders prepared under different conditions does not make much difference except that annealed at 750C for one hour. The two semi-circles and a line with a angle of 45 to real axis in the impedance spectrum of LiMn2O4 electrode correspond to the absorption of lithium ion onto the surface of LiMn2O4, the charge transfer and the diffusion of lithium within LiMn2O4, respectively.LiMn2O4 thin films were prepared by solution deposition using spin-coating technique. The influence of a lot of factors on the quality and properties of the thin films was discussed. The characterization of LiMn2O4 thin films prepared by both conventional and rapid thermal annealing and the diffusion of lithium ion in LiMn2O4 thin film were also studied. The resultsshow that the solvent and concentration of LiMn2O4 precursor solution, spin-coating speed, heating speed, annealing temperature and time etc. have great effect on the properties of the thin films. For the thin films heat-treated by conventional thermal annealing, their first discharge capacity increases first and then decreases with the increase of annealing temperature or time. The thin films annealed at 750 C for 10 or 30 minutes show high capacity and good cycling behavior with a capacity loss of 0.038% and 0.05% per cycle after being cycled 100 times, respectively. The crystallinity and the particle size of LiMn2O4 thin films prepared by rapid thermal annealing improves and becomes bigger with the increase of annealing temperature or time. The particle size of the thin films annealed at 700 C, 750C and 800C for 2 minutes or annealed at 750C for 1,2 and 4 minutes by rapid thermal annealing is between 0.02 and 0.05 m. The surface of these films is very smooth, which is very favorable for avoiding of the short of thin-film batteries. The capacity of the thin films with good cycling behavior generally increases with the increase of annealing temperature or time. The diffusion coefficient of lithium ion in the LiMn2O4 thin film annealed at 750C for 2 minutes is about 10-11 cm2/s.The preparation and characterization of Li1.3Al0.3Ti1.7(PO4)3 powders and sintered pellets derived by sol-gel method and solid-state reaction were carried out and comparatively studied. Compared with that prepared by solid-state reaction, the pellet prepared by sol-gel possesses higher compactness, higher ionic conductivity and lower activation ener...
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