| The global researchers have paid great attention to new energy storage materials since the shortage of energy and environmental pollution brought by fossil energy.This article designs a new energy storage materials(referred to as the accumulator)which the anion and cation are intercalated in carbon as positive-negative material based on work principle of the lithium-ion batteries and super capacitors.The study of the accumulator shows that no lithium ion in the positive and negative cathode.Ions provided by the electrolyte solution.Anion and cation in the electrolyte solution are moving to the positive and negative of the accumulator respectively when charging,and embed into the positive and negative electrode carbon layer.In order to balanced the cation in negative electrode,Electrons are removed from the positive electrode carbon into the negative electrode carbon through the external circuit.We focus on the electrolyte solution and carbon electrode material in this paper.Firstly,we studied the method of Li-ion and other cation ion intercalation into CMB-N7 Mesocarbon microbeads in common electrolyte and ionic liquid electrolyte.It suggested that in 80-3 electrolyte(1.0mol/L LIPF6/(EC+DMC),Microvast Company)only Li-ion can embed in CMB-N7,but both Li-ion and cation ion in ionic liquid can embed in CMB-N7 when the ionic liquid as the electrolyte.While,the double carbon CMB-N7 cell cannot work in 80-3 electrolyte,but worked well in ionic liquid electrolyte.One of the best was IL-2 ionic liquid(1-ethyl-1-methyl pyrrolidone two(three fluoro methyl sulfonyl)imide)as the electrolyte.The average discharging specific capacity of symmetric electrode storage in 20 cycles was 62mAh/g,the average charging and discharging efficiency was 48%.Secondly,we discussed the the capacity of charging and discharging of IL-2 ionic liquid based symmetric storage.It was confirmed that natural flake graphite and CMB-N7 carbon microspheres have a better specific capacity.However,the charging and discharging efficiency of CMB-N7 carbon microspheres was low.What's more,the CMB-N7 carbon microspheres cost more money.So the natural flake graphite was the best carbon electrode materials.We used grinding method to get different size of natural flake graphite and take it as electrode materials.Then we assembled the accumulator and tested it.It suggested that the natural flake graphite electrode material which particle size D50 = 6.531?m was preferable,the average discharging specific capacity of electrode storage in 20 cycles was 85mAh/g,the average charging and discharging efficiency was 61%.The reason of the enhanced capacity of the accumulator is natural graphite was that sanded and the graphite layer spacing increases,ions embed in it easier.Finally,we studied the cycle performance of the accumulator when the positive and negative carbon material is different.Selection of particle size D50 = 6.531 ?m flake natural graphite material as negative electrode material,without pretreated carbon-based material as positive material,IL-2 ionic liquid as electrolyte solution and assembled the accumulator,It suggested that the natural graphite was the best cathode material.Then the sanded carbon-based materials as a positive electrode material,untreated carbon-based material as a negative electrode material,IL-2 ionic liquid as electrolyte solution assembled the accumulator.The best matching negative electrode material and positive electrode material were selected according to the cycle performance of the accumulator,where in the best positive cathode material is the sanded natural flake graphite which the particle size D50 = 6.531?m,negative electrode material was natural graphite without sanded.The average discharging specific capacity of the electrode storage in 20 cycles was 83.6mAh/g,the average charging and discharging efficiency was 60.9%.The accumulator results demonstrated the cation in the ionic liquid electrolyte solution embed in the negative electrode carbon material was relatively easy. |
PDF Full Text Request