Study Of Debris Damage On Space Battery Covers And Silicon-based Materials As Electrode

Energy conversion and storage devices are usually set up in spacecraft,which mainly contains solar cells and lithium-ion batteries,respectively,to ensure the spacecraft normal operation.In this paper,we studied on two projects,one is to simulate impact damage with debris'rotation and multiple accumulation effects on quartz glass as solar cell cover plate;the other is to improve the energy storage capacity of lithium-ion battery.If the flyer was driven by laser,the impact and damage could achieve one-to-one correspondence.The single and multiple impacts were performed by the flyer with a high velocity in single direction impacting on static target.Taking advantage of the velocity relativity principle,impact occurs on rotating target,which can achieve the simulation of impact by rotating debris with high velocity.The impact craters'depths and diameters by single impact,multiple impacts and rotating impact were analyzed through 3D microscope,SEM,and XRD.The result showed that the multiple impacts had an accumulative effect,which caused serious damage area with a deeper and wider crater comparing to a single impact.In addition,the rotating impact effect could aggravate damage.When the silicon wafer was irradiated by high energy IR laser with flat distribution,a large amount of SiO_x ultra fine nanoparticles with higher oxygen content were generated at ablation damage area edge.The electrochemical performance of SiO_x ultra fine nanoparticles was evaluated as anode material of lithium-ion battery.At current density of 0.2 Ag^-1,the maximum reversible capacity430 mAhg^-1was obtained at the 451st cycle.Although the specific capacity descendsed slowly with cycles increasing,it retained 344 mAhg^-1at 800th cycle.A novel Si/SiO_x composite thin film was prepared by pulsed laser deposition as the anode of Lithium-ion battery.According to the SEM,TEM and HRTEM data,it was found that the film was amorphous SiO_x reticular texture structure with micro sized Si sphere supporting.At current density of 0.2 Ag^-1,Si/SiO_x composite thin-film as electrode,the reversible capacity sustained to 689mAhg^-11 after 100 cycles.When the current density increased to 4 Ag^-1,the reversible capacity was still 281mAhg^-1.The excellent cycle and rate performance were mainly due to the particularity of this structure which could alleviate volume expansion effect during the repetitive deep charge/discharge processes.This method also provided a possibility of structure for the preparation of other materials.