Numerical Simulation And Experimental Research On Silicon Particles Impacting On The Copper Substrate During The Process Of Cold Spray

Silicon-based materials are considered as the next generation anode of Lithium ion recharge batteries due to the highest theoretical capacity. However, the huge volume expansion emerges during the charging and discharging processes, which will result in the electrode failure and is curial to the large-scale production of the silicon-based anode.In this thesis, cold spraying technology is adopted to manufacture the silicon-based anodeby silicon particles impacting on a copper substrate. Numerical modeling and cold spraying experiment are performed to investigate the impact property of silicon particles.Firstly, the deposition process of silicon particleon a copper substrate is simulated under the different conditions of particle sizes, different-typesparticles.And the characteristics of the deposition process and the deformation morphology of the particles and substrate are represented. Moreover, thecritical impactspeed of silicon particles on the copper is obtained. At the same time, it is found that the deposition process and mechanismof silicon particles are different from the metal particles. Finally, the coating of the silicon power deposited on the copper substrate is manufactured through the cold spraying technology under different conditions of the primary steam pressure, the primary temperatureandthe particle size. Furthermore, the properties of cross section and surface morphology of the coating samples are observed by SEM, and the experimental results are comparedwith the corresponding simulation results.The results show that the coatings with pores and uneven surface form when the low plastic silicon particles are deposited on the copper substrate. Then, the coating quality can be improved by adding high plastic particles into silicon particles or increasing the spraying times. Not only a new manufacturing method of silicon-based anode is proved, but also the huge volume expansion may be weakened by the porosity of the silicon coating.