| With the development of IC and MEMS industry, it is urgent to develop the compatible power source. Thin film batteries proved to be the best choice because the quality of ultrathin, compatible and flexible.It is well known that thin film electrodes are free of additives and binders used in powder-based electrodes and can be employed as an "ideal" system for the fundamental studies because they could yield greater insight into the intrinsic properties of the electrode materials. In this thesis, pulsed laser deposition (PLD) was utilized to prepare the heterogeneous mixture of nano-material thin-film and double-anion material thin-film, used as electrode material for Li-ion battery.The structure, composition, surface morphology, electrochemical properties and lithium reaction mechanism of the materials were examined.Besides, either thin-film batteries or normal sized batteries, the electric charge transfer within batteries are based on the movement of cations. Here, we studied on the Metal-Halides battery system, which is proved to be based on anion transport mechanism. Both all-solid-state and liquid electrolyte batteries are designed and constructed, and its electrochemistry performance is tested. By comparing with each other, we found the ion-transfer mechanism altered within different condition. This proved anion transparent battery system possesses good electrochemical performance, either as all-solid-state or normal sized batteries provide a novel case of design energy storage devices.Today the preferred thin-film battery is the all-solid-state thin film Li-ion battery. It is the most developed candidate of the power source for the next generation microchips and industry of information. Here, we successfully prepared the large sized all-solid-state thin film Li-ion batteries, and integrated with RFID devices to raised its performance of recognition. Besides, we also realized "non-contactable"charging of thin film batteries by integrating with radio-frequency charging device. It is meaningful to expand the application of thin-film batteries.The first part of the thesis is studying on thin-film electrode material prepared by PLD technique. Use PLD instrument to deposit electrode material on stainless steel substrate, assemble a battery with Li metal as counter electrode and reference electrode. Characterizecharging-discharging performance and electrochemical feature. Using physical characterization method to identify the change of composition and status of the electrode material during electrochemical reaction, such as X-Ray diffraction (XRD), high-resolution transparent electroscope (HRTEM), selected area electronic diffraction (SAED) and X-Ray spectroscopy, to explore the electrochemical reaction mechanism. Following materials have been studied:1. Heterogeneous mixture nanocomposite. Altering the composition of the target and other parameter of PLD to prepare the Li2Se-MSex (M= Cu, Sb) thin-film electrode. By characterize the electrochemical performance and the composition and structure during charging-discharging process, we found Li2Se has been decomposed and produced reversely when cycling. The electrochemical reaction mechanism is not insertion/deinsertion, but the conversion mechanism, mainly concluding reversible conversion reaction of MSex and Li2Se.2. Double anion material. This is first time to use double anion material as thin-film electrode material. The electrochemical performance suggest the capacity of initial discharging can reach 884mAh/g, and in the following cycle drop down to 629 mAh/g. The average capacity fading except the first cycle is less than 0.1%. It is found that the electrochemical reaction during charging-discharging process including the decomposition of FeOF to produce Fe, Fe2O3 and LiF, also the conversion reaction between Fe and Fe2O3.The research on heterogeneousmixture of Li2Se-MSex (M= Cu, Sb) nanocomposite provide the direct prove that the inertia containing lithium can be decomposed and reproduced reversibly, showed possibility of cathode based on conversion mechanism. Sb2Se5 is successfully synthesized by electrochemical oxidation for the first time, providing a strategy to prepare high oxidation-state metal compound.Study on FeOF thin-film electrode material employed double anion compound as anode material for thin-film lithium-ion batteries for the first time, which proved that there is electrochemical selectivity between different matrixes containing lithium in conversion reaction mechanism. It will guild us in the exploration of new high capacity lithium-storage material.The second part of this paper is the study on M/Xn(M=Al?Mg, X=Br?I) battery.The metal/iodine thin-film battery can operate with solid electrolyte showing high voltage and moderate rate performances. The regular cell based on organic liquid electrolyte also showed similar electrochemical performance, in which Al or Mg sheet was used as a work electrode and a carbon sheet was used as a counter electrode.As a comparison, the aqueous electrolyte based battery is assembled. Ac impedance spectra indicated that the resistance of the Al/I2 cell in water solution reduced during discharging process gradually, while the resistance of the Al/I2 cell in the acetonitrile solution increased during discharging process. This could be due to the formation of a layer of amorphous AlI3 on the surface of aluminum anode, which was confirmed by the scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy and selected area electron diffraction measurements.An I- conductor, LiI(HPN)4 with 20 wt% 15nm SiO2 was employed as solid electrolyte between Al and 12 electrode to assemble the solid-state Al-I2 cell for further clarifying the transport mechanism. Our results demonstrated that the transport mechanism of Al-I2 cell in the water may be involved in both cation and anion transport mechanism, but in non-aqueous solution, it may be involved in cation transport mechanism. So the anion-conducting electrochemical batteries can be also promising for energy storage compared to cation-conducting systems in current batteries.The last part of this paper is preparing and application of large-sized all-solid-state thin-film lithium ion batteries. Deposited a layer of metal on clean surface of glass or Si-sheet as electric charge collector employing DC-sputtering, a layer of LiMn2O4 or LiFe(WO4)2 as cathode material by RF-sputtering, a layer of LiPON as electrolyte by RF-sputtering, and a layer of lithium metal as anode by thermal vaporization to assembling an all-solid-state thin-film lithium ion batteries. By adjusting and controlling the target composition and preparing condition, the battery, effective area of which is larger than 4 cm2, is successfully prepared. For application, we've integrated the large area thin-film battery with RFID tag to assemble an active RFID tag by designing the shape of the battery and the antenna. The result showed the improvement of performance on recognition comparing with passive RFID tag. On the other hand, the experiment result of integrating RF-charging devices with thin-film battery shows the charging current larger than 5?A is produced when distance between the charging device and the battery is 4.2cm, and the battery after charging shows regular discharging performance, realized the "none-contactable" charging. This technique is useful for expanding the applicant of all-solid-state thin-film batteries. |
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