Growing Nano Copper Oxide In-situ To Stabilize Lithium Metalanode And Their Electrochemical Performance

lithium metal is the best choice of anode for the lithium metal batteries due to its high theoretical specific capacity of 3860 m Ah g^-1,lowest metal density of0.534 g cm^-3and low electrode potential of-3.04 V?vs.the standard hydrogen electrode?.However,Li dendrites,interface reaction,large volume change and short cycle life in the cycling seriously affect the cyclic performance and safety of lithium metal anode which restricts the development and application of lithium metal batteries.In order to solve the problems mentioned above,a modification of lithium metal anode was carried out.To improve the performance and safety of lithium metal anode,different nano-Cu O substrate for accommodating lithium was prepared to inhibit lithium dendrites and adapt to volume changes.The specific research contents and results are as follows:?1?Growing CuO nanoclusters array?CuO-NCA?in situ to stabilize lithium metal anode.Firstly,Cu?OH?₂nanoclusters array was grown in situ on the surface of copper foil by low temperature wet chemical method using Na OH solution,NH₃·H₂O solution and H₂O₂solution as raw materials,and then the Cu O nanoclusters array was obtained by dehydrating with heat treatment.There is low nucleation potential and low interface impedance due to the special structure of nanoclusters array,which can effectively guide the uniform deposition of lithium ions.The high surface area can effectively lower the local current density on the electrode surface,and can also adapt to volume change caused by Li deposition/stripping.Therefore,there is a more excellent cyclic stability and rate performance for Cu O-NCA electrode.High average coulombic efficiency of 98%was got in the first 230 cycles in Li|Cu O-NCA half cell and cycling stably without short circuit within 1000 hours in Li|Li/Cu O-NCA symmetric cell.The full cells composed of Li FPO₄cathode and Li/Cu O-NCA anode still retains 77.2%of capacity after 300 cycles at a ratio of 0.5 C,with an average decay rate of 0.076%per cycle and an average coulombic efficiency of98.8%.?2?Growing CuO discrete nanowires?CuO-DNW?in situ to stabilize lithium metal anode.Firstly,Cu?OH?₂nanowires was grown in situ on the surface of copper foil by low temperature wet chemical method using Na OH solution and?NH₄?₂S₂O₈solution as raw materials,and then the multidirectional Cu O discrete nanowires was obtained by dehydrating with heat treatment.We study its electrochemical properties by comparing the different concentrations of Na OH solution for Cu O structure.The current density on the surface of Cu O-DNW-10 was reduced effectively due to the larger specific surface area of the discrete nanowires structure,which was provided the place of deposition and adapted to Li deposition/stripping.Stable cycle of 120 cycles with the high coulombic efficiency of 98.3%and the low polarization voltage of 24 m V in a Li|Cu O-DNW-10 half cell can be obtained and there is without short circuit within 900 hours in Li|Li/Cu O-DNW-10 symmetrical cell.