| Based on the calculation formula of organic conducting polymers theory specific capacity of the anode material used in lithium ion battery,we can enhance the capacity of the anode material by raising the doping ratio and active sites numbers of repetitive unit.Electrochemical polymerization with simple operation,also has the electrochemical doping and the ion doping,increasing the rate of doped polymer materials made the specific capacity increased.In addition,the polymer can be a film after polymerization,thus reducing the influence of the sticky agent and conductive material to batteries.The active sites numbers of repetitive unit can affect theory specific capacity directly.The active monomer of multi-electron reaction can be designed,synthesized,and aggregated as a anode material of lithium ion battery.Compared to the PPy,the composites prepared by electrochemical in situ polymerization have a enhance performance.At the charge and discharge rate of 20mA·g-1,the PPy-CF electrode displayed a discharge specific capacity of 145 mAh·g-1at the first cycle,while the PPy-GO electrode is 176.1 mAh·g-1.After 50 cycles,specific capacity loss rates were 29.5%and 26.5%respectively.They also have a better rate performance.At the charge and discharge rate of 160 mA·g-1,the PPy-CF electrode displayed a discharge specific capacity of 116.9 mAh·g-1,while the PPy-GO electrode is 123.4 mAh·g-1.Electrochemical method can improve the performance by raising doping ratio of the material.The carbon material added can change the morphology of the material,which can improve the utilization of active material.We prepare different proportion?Py:Py-C-TEMPO=4:1,Py:Py-C-TEMPO=8:1?copolymer by electrochemical oxidation.Discharge platform of PPy has a certain improvement.There shows two voltage slowing decline trend near 3.5 V and 2.7 V respectively.The Py:Py-C-TEMPO=4:1 copolymer electrode materials has a specific capacity of 70.9 mAh·g-1 at the charge and discharge rate of 20 mA·g-1,while the Py:Py-C-TEMPO=8:1 copolymer electrode is 62.6 mAh·g-1.The improvement of the performance can be attributed to of the addition of the Py-C-TEMPO and the electrochemical doping ratio of material which was prepared.Compared to the polytriphenylamine,poly?4,4?,4?-tris?N,N-diphenyl-amino?triphenylamine??PTDATA?electrode shows a higher discharge specific capacity.At the charge and discharge rate of 20 mA·g-1,the first discharge specific capacity of PTDATA is 133.1 mAh·g-1.It shows four charge and discharge voltage platforms near to 3.8,3.4,3.2 and 2.5 V respectively.In addition,it also has a better cycle stability that capacity loss is 21.79%after 56 cycles.The improved performance is due to the high density of free radicals of the PTDATA.The PTDATA also has a cross-linked morphology.Compared to the polytriphenylamine?PTPA?electrode,poly?1,3,5-tris?diphenylamino?benzene??PTDAB?electrode shows a good cycle performance.At the charge and discharge rate of 20 mA·g-1,the first discharge specific capacity of PTDAB is 64.6 mAh·g-1.After 56 cycles,the capacity loss is 1.23%.The reunion phenomenon of polymer PTDAB leads to the lower specific capacity.The similarity of polymer molecular structure eradicate the third-order discharge platform. |
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