| Lithium is considered as one of the best anode material for its advantage of high theoretical specific capacity and low electrode potential, etc., but it will be suffering with poor cycling performance and safety issues due to the growth of lithium dendrite. Transition metal oxides are also considered as very promising anode materials for their high specific capacity, but the poor transport properties of lithium ion and charge limit their application. In this paper, the distribution of current density and potential in three-dimensional netlike structured electrode and the effect of thickness for the surface active materials layer on the charge/discharge performance of the electrode were discussed. The three-dimensional (3D) netlike structured lithium metal, NiO, Co3O4 anode were also prepared using high surface area three-dimensional metal netlike substrate as current collector and support to improve their cycling performance and rate capability. The use of three-dimensional netlike structure provides an effective way to improve the electrochemical performance of electrode material.By mathematical modeling, we can found that the electrode potential decreased with the increase of the thickness on the electrode when consider the liquid resistance and the control of linear polarization. The distribution of current density and potential in the direction of thickness were more homogeneous as the decrease of electrode thickness. The similar results were also obtained when considering the conditions of middle and strong polarization. When considering the solid-phase resistance, the electrode reaction occurred mainly in the central of electrode. The utilization of active materials was decreased with the increase of thickness for electrode on the assumption that solid diffusion is the main control factor, hence the specific capacity of the electrode was lowered. 3D netlike structured lithium metal anode was prepared by electrodeposition in the organic electrolyte system, and the deposition process was optimized. The deposition current desity was 1 mA·cm-2, the deposition capacity was bollow 20 mA·cm-2. The results showed that the cell with 3D netlike structured lithium as anode shows excellent cycleability and rate performance, and the cycling capacity retention rate of cell with as-prepared 3D netlike lithium as anode remained more than 90% at the charge/discharge current density of 4mA?cm-2 after 100 times, while only 50% for the cell with lithium foil as the anode under the same conditions. The increased real surface area of 3D netlike lithium caused the decrease of real current density on unit surface area and polarization during dissolution/deposition of lithium, and prohibits the formation of Li dendrite, hence the cyclic performance and high-rate behavior of 3D netlike lithium was improved significantly.3D netlike NiO was prepared by a solid phase oxidation method using 3D foam nickel as current collecter and metal source. The results showed that the crystal size increases with the increase in the annealing temperature. Irreversible capacity loss at the first cycle can be decreased by the decrease of crystal size. The porous surface structure of NiO prepard at 700℃increased the active site for effective reaction, enhanced the ability of diffusion for lithium ion and accommodated the change of volume, hence a better electrochemical performance was obtained. The 3D netlike NiO exhibited higher reversible capacity as well as higher rate capability in comparison to NiO foil. The reaction mechanism of NiO is a tow-step redox reaction.3D netlike Co3O4 anode was prepard by electrodeposition combined with post-oxidation. The grain size and surface structure of Co3O4 were different with the different deposition current density, temperature, and the solid phase oxidation temperature and thereby affecting the electrochemical properties of electrode. The charge/discharge capacity of 3D netlike Co3O4 increases with the increase in the deposition current density. At 800mA?cm-2, high porosity porous foam self-supporting structured Co3O4 with high specific surface area was abtained by the release hydrogen bubble as template, which exhibited a high discharge capacity of up to 1200 mAh?g-1 with little capacity loss for more than 35 cycles. The discharge capacity reduced with the decrease of crystal size which caused by low oxidation temperature. 3D netlike structured Co3O4 with hexagonal Co3O4 nano-film layer can be prepared by hydrothermal method. The first charge/discharge capacities were 1138mAh?g-1 and 1589mAh?g-1, respectively. The discharge capacity of the anode was still 533.3mAh?g-1 at 10C rate, which shows a good rate performance.In addition, Co3O4 nanoplate arrays was constructed on 3D netlike substrate by eletrodeposition combined with oxidation. The first charge and discharge capacity of the as-prepared anode were 1019.4 and 1418.3 mAh?g-1, respectively, with no capacity fade up to 45 cycles. The discharge capacity was also 533.3mAh?g-1 at 10C rate, which was more than 51.34% of the capacity at 0.5C. The interconnect nanoplate array structure can reduce the diffusion dimension of lithium-ion, accommodate the volume change during charge/discharge, thereby improving the charge/discharge performance and rate capability of 3D netlike Co3O4. The results show that the reaction mechanism of Co3O4 anode is a multi-step redox reaction.
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