Design Of High Specific Capacity Quinone Cathode Materials And Their Applications In Lithium/Sodium Ion Batteries

Traditional lithium ion batteries based on inorganic transition metal?Ni,Mn,Co,etc.?oxide cathode and graphite anode are convenient for people.Now,however,some weaknesses are emerging.In terms of capacity,the inorganic transition metal oxide-graphite system can no longer meet the needs of electric vehicles,electric aircraft,and other large equipment.In terms of resources,the reserves of transition metal elements in the crust are limited.In terms of the environment,heavy metals in waste lithium ion batteries cannot be effectively recovered,which will cause serious pollution to the environment.Therefore,it is urgent to develop cathode materials with high theoretical capacity,abundant sources,and green environmental protection.Organic quinone compounds with carbonyl active sites satisfy the embedding/de-embedding of different metal ions.They possess the advantages of high theoretical capacity,strong structural designation,abundant sources,and environmental friendliness.However,quinone compounds dissolve in the organic electrolyte during charging and discharging easily,which seriously hinders the practical application of them in lithium ion batteries.In this paper,the electrochemical behavior of cathode material Pillar[5]quinone?P5Q?,a kind of organic quinone compound,was studied.Aims at the issue of dissolution of P5Q during the charge-discharge,used the simple"perfusion method",P5Q is immobilized in the channel of CMK-3,and the cycle stability and rate performance have been significantly improved.1.As the cathode material of lithium ion battery,the initial capacity of P5Q is 420mAh g^-1,which is close to the theoretical value.The 100%active site utilization of P5Q was demonstrated.The lithium storage performance of P5Q,P5Q/CMK-3?1:1?,and?1:2?were compared,and,the electrochemical performance of P5Q/CMK-3?1:2?was the best.At 0.1C,the capacity is reduced from 420 mAh g^-1 to 300 mAh g^-1 after 100 cycles,with a retention rate of 71%.At 2 C,the capacity is 173 mAh g^-1.2.As the cathode material of sodium ion battery,the initial capacity of P5Q is 418mAh g^-1 at 0.1 C.The sodium storage performance of three kinds of materials,P5Q,P5Q/CMK-3?1:1?and P5Q/CMK-3?1:2?,were compared.P5Q/CMK-3?1:2?showed the best performance in cyclic stability.After 300 cycles,it decayed to 290 mAh g^-1,and the capacity retention rate was as high as 69%.For P5Q and P5Q/CMK-3?1:1?,the capacity retention rate of 100 cycles at 0.1 C was 27%and 32%,respectively.Compared with lithium ion battery,P5Q/CMK-3?1:2?showed the more obvious performance improvement in sodium ion battery.Therefore,the coating method effectively eases the dissolution of P5Q in the electrolyte,displays the advantages of high specific capacity of P5Q,improves the cycle stability and rate performance.