| Currently, lithium-ion batteries (LIBs) have been applied in various fields, such as hybrid electric vehicles (HEVs), electric vehicles (EVs) and stationary energy storage due to their advantages of high energy density, long lifespan and environmental friendly effect. However, the current commercial graphite anode which has the limited theoretical capacity of 372mAh g-1 could hardly meet the increasing requirements of energy. Therefore, it is significant to find better alternative anode materials. Transition metal oxide and tin-based material are common anode materials which have high theoretical capacities. Fe3O4, Sn-Sb alloy and Sn-Co alloy have been studied frequently. They all have high theoretical capacities But the big problem with Fe3O4 and tin-based materials is large volume variation during the charge and discharge process, and eventually it would lead to the aggregation of nanoparticles and the disintegration of the electrode, and then influence the electrochemical properties. However, nanometer materials and three-dimensional (3D) structured electrode, bring the solution to the problem. And, with the increasing requirements for portable energy storage and the miniaturization of portable, electronic devices have led to the rapid development of electrochemical power sources that meet the size and energy needs. Three-dimensional microbattery (3D-MB) architecture has been proposed. For this, this paper designed one kind of 3D and high-aspect-ratio nanowires array electrode materials which can accommodate the volume expansion. Thus, it also can improve the cycle performance and rate performance of the battery. It also has the opportunities to be used in the microbattery.This paper synthesized 3D nanowires array electrodes through template-assisted method. We investigated the pulse time, current and other factors which affected the synthesis of the electrode. Then the active materials of Fe3O4, SnSb and SnSbCo were deposited onto the Cu nanowires array through electrodeposition. In order to determine the best parameters eventually, we explored the deposition time, current and the heat treatment which affected the synthesis of the hybrid electrode. Comparing with planar electrodes, we characterized the electrochemical properties of their counterpart 3D electrodes. It is found that 3D Cu@Fe3O4 nanowires array electrode performs better than the planar one on the first discharge capacity, cycle stability and rate performance. But overall, the material did not achieve the ideal result of high discharge capacity. Therefore, we changed the active material system and explored the electrochemical properties of 3D Cu@SnSb nanowires array electrode. We found that, the first discharge capacity was 1800 uAh cm-2, nearly 800μAh cm-2 higher than that of the Cu@Fe3O4 electrode. But after 80 cycles, the capacity of Cu@SnSb electrode declined. We characterized the electrode materials after cycling, and found that the structure of the 3D electrode had been damaged more or less after the charge/discharge reactions. Therefore, we added Co elements into the SnSb. Through the electrochemical measurements, we found the 3D Cu@SnSbCo electrodes performed better than Cu@Fe3O4, and Cu@SnSb electrodes after heat treatment.3D Cu@SnSbCo electrodes have the high first discharge capacity of 1019μAh cm-2, after the irreversible reaction, the capacity declined to 800μAh cm-2. And after 80 cycles, there were almost no further decline. We characterized the morphology of the after-cycling electrode and found that the 3D structure maintained good.
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