| In the past decades, a great number of portable electronic devices, such as wireless phone, camera and laptop computers have been developed rapidly, and lithium ion batteries are becoming their main power sources because of their high capacity and specific energy. Moreover, lithium ion battery is considered as an attractive candidate for green power source used in automobiles and vehicle. In order to keep pace with the miniaturization of micro-electronic devices, thin-film rechargeable lithium ion microbattery has drawn notable attention. Many efforts have been made to find out novel electrode materials and to improve the electrochemical performance of traditional electrode materials.Pulsed laser deposition has been recognized as a versatile technique for fabricating of thin films of multi-component metal oxides. It has many advantages, such as high deposition rate, the capability for reactive deposition in ambient gases, and the ability to transfer nearly the original stoichiometry of a bulk target to the deposited film. Therefore, there are many publications on the preparation of thin film electrode materials for Li-ion batteries by PLD method. In this thesis, we report the fabrication of several new thin-film electrode materials by PLD method, including NiFe2O4, Bi2O3, Ni-V2O5 and Ag-V2O5 composite films, and the investigation on electrochemical properties of these electrode materials:1. Amorphous Ni-V2O5 composite film were successfully prepared by 355nm pulsed laser reactive deposition for the first time. The optimum experimental conditions for the film preparation are a temperature of substrate at 300 oC, 13 Pa ambient oxygen gas, deposition duration of 0.5h. We found that the Ni0.3V2O5 composite film electrode exhibited best electrochemical performance among the NixV2O5 film electrodes with x = 0.1,03,0.5. This film electrode retained a capacity of 365 mAh/g with excellentreversibility upon cycling with no obvious fading over more than 1000 cycles at a rate of 2C.2. Silver-vanadium pentoxide composite films have been fabricated by 355nm pulsed laser reactive deposition. XRD and SEM analyses showed that the composite films AgxV2O5 (x=0.1-0.5) deposited at a substrate temperature Ts of 300 oC and an oxygen pressure of 13 Pa for 0.5 h were amorphous and became a polycrystalline structure after 2h of deposition. The valence states of Ag and V for AgxV2O5 composite film were examined by XPS measurement. The amorphous Ag0.5V2O5 composite film electrode exhibited a specific capacity as high as 396 mAh/g in the range of 4.0-1.0 V at a 2C rate and remained a capacity of 260 mAh/g at a 20C rate with no obvious fading upon cycling over more than 1000 cycles. In addition, the electronic conductivities of AgxV2O5 composite films were 2-3 orders of magnitude higher than that of pure V2O5 film. The dramatically improved electrochemical performance of these electrodes might be related to the changes in microstruture and the enhancement of the electronic conductivities for the AgxV2O5 composite films. Furthermore, an all-solid-state lithium battery of Li/LiPON/ Ag0.5V2O5, in which the Ag0.5V2O5 film was used as a cathode, was fabricated and it exhibited an average reversible capacity of 40 (Ah/(m-cm2 upon cycling over more than 100 cycles between 3.5 and 1.0V. 3. The nanocrystalline nickel ferrite (NiFe2O4) thin films with spinel structure deposited on stainless steel substrates have been fabricated by 355nm pulsed laser reactive deposition for the first time. The irreversible capacity of nanocrystalline NiFe2O4 film electrode during the first discharge reached to 610 mAh/g at C/2 rate, accompanied by irreversible structural transformation into amorphous phase. In addition, the discharge capacity of NiFe2O4 film electrode depends strongly on the discharge rate and the voltage range. In the voltage range of 3.0-0.01V, the filmdelivered a reversible capacity close to 450 mAh/g at C/2 and exhibited a good cycling reversibility with no obvious fading for over more than 100 cycles. B...
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