Study On Anode And Structure For High Performance Aluminium-air Batteries

Aluminium has the advantages of low cost,high specific capacity,safety and environmental friendliness.The theoretical specific energy of Aluminium air battery can reach 8.1 kwh·kg^-1,so it has a broad application prospect in the field of new energy vehicles.However,due to the problems of hydrogen evolution,self-corrosion and surface passivation in the process of discharge,the energy density,working voltage and battery utilization rate of Aluminium air battery will decrease,which limits the application of Aluminium air battery and makes it difficult to meet the current commercial demand.In order to solve the above problems,a series of methods were used to modify the anode and structure of Aluminium air battery in order to improve the discharge performance of Aluminium air battery.（1）The effect of Aluminium alloy prepared by 3D printing and powder metallurgy as anode on the electrochemical performance of Aluminium air battery was studied.The results show that the Aluminium anode prepared by 3D printing has better electrochemical activity than the Aluminium anode prepared by traditional powder metallurgy due to a large number of macro defects on its surface and the existence of grain boundaries.However,due to the low density and many surface defects of 3D printed Aluminium samples,the self corrosion rate is more severe.（2）A series of Aluminium anodes with different grain sizes were prepared by adding different Al-Ti-B refiners.The results show that the performance of the battery increases with the decrease of the grain size of the Aluminium anode.The Aluminium anode with the smallest grain size（～100μm）has the highest operating voltage,the largest specific capacity and the best performance.Compared with Al-537（average grain size of 537μm）,the energy density of Al-108（with average grain size of 108μm）is increased by 105%.The improvement of battery performance is mainly attributed to the increase of grain boundary density and the formation of more uniform microstructure after refinement.（3）The influence of the distance between anode and cathode on the discharge performance of Aluminium air battery was studied.The results show that in Na OH solution,the voltage decreases with the increase of electrode plate distance,while in Na Cl solution,the voltage first increases and then decreases with the increase of electrode plate distance.However,in 4 M Na OH solution and 10 wt%Na Cl solution,the maximum power decreases with the increase of plate space.