Preparation Of Advanced Anode Materials Based On Three-dimensional Porous Metals And Research On High-efficiency Energy Storage

The traditional graphite anode has a low theoretical specific capacity(only 372mAh g^-1),which has become a key factor hindering the performance improvement of lithium-ion batteries.Therefore,the development of advanced anode materials with high performance has become a research hotspot for scholars.However,most of the anode materials have problems such as large volume changes during charge/discharge and low conductivity,which need to be solved urgently.3D porous metals have attracted much attention due to their excellent metal properties and 3D porous comprehensive properties.This paper is based on 3D porous metal for the preparation of advanced anode materials and high-efficiency energy storage research.Combining 3D porous metal characteristics with anode materials,3D porous structure can alleviate the volume expansion of active materials,shorten the electron/ion transmission path,and enhance the cycle and rate performance of the electrode.The main contents of this paper are as follows:（1）Preparation of LiNi_0.5Mn_1.5O₄ reinforced NiO composite anode material with fast Li⁺channel and high energy storage efficiency.In this experiment,LNMO/NiO composites with good crystallinity were successfully prepared by the dealloying and solid-phase sintering.The content of LNMO in the composite electrodes prepared by dealloying for 2 h,3 h and 4 h are 13.5%,8.3%and 6.1%,respectively.The LNMO/NiO Composite electrodes prepared by dealloying for 3 h exhibits the best cycle performance and rate performance.The stable reversible specific capacity is 398.8 mAh g^-1 after 200 cycles at 0.1 C current density,and the high stable reversible specific capacity of 395.9 mAh g^-1 and mAh g^-1 are still obtained after 1000 cycles at high current density of 1 C and 2 C.The results also show that the electrochemical properties of the no lithium and ball milled samples are significantly reduced due to the lack of fast Li⁺channels and 3D porous structure.The specific capacities of the no lithium and ball milled samples after 200 cycles are only 209.1 mAh g^-1 and 251.3 mAh g^-1 at 0.1C current density.（2）Preparation of 3D continuous Si/Cu based integrated composite electrode and research on high-efficiency energy storage.In the experiment,3DP-Si/Cu composite electrodes with 3D porous structure were prepared by the improved NIPS method and solid-phase sintering technology to realize the integration of active material and current collector.The effects of different reduction temperature and active material loading on the 3DP Si/Cu composite electrode were investigated.The results show that the composite electrodes with reduction temperature of 800^oC and content of Si powder of4.8 wt%have better morphology and structure,which show better electrochemical performance.At a current density of 0.05 C,the stable reversible specific capacity after100 cycles is as high as 1809.2 mAh g^-1.This novel electrode structure design opens the way for the next generation of Si/3D porous metal composite anode materials for energy storage devices.