Study On The Preparation And Performance Of Carbon Nano Conductive Agent For Leadcarbon Battery

With the continuous consumption of fossil energy by human beings,newly energy that can replace fossil energy has been widely researched among various countries.Among them,secondary batteries that can provide power and energy storage developes very rapidly.Lead-acid batteries,as a secondary battery with the longest history and the most mature production technology,has been occupied most of the market,but the negative electrode of the lead-acid battery produces sulfation during use,and finally a lead sulfate passivation layer is formed on the surface of the electrode plate,which hinders the electrochemical reaction of the negative electrode and arises the battery be failure.Carbon nanomaterials in the negative electrode can effectively alleviate the irreversible sulfation of the negative electrode thanks to the structure of the conductive network,the electric double layer capacitance effect,the formation of the porous structure and the space effect,which improves the performance of the battery and prolongs the service life of the battery.However,the low hydrogen evolution overpotential of carbon materials aggravates the hydrogen evolution reaction of the negative electrode,the fluidity of the electrolyte will decrease due to the losing water phenomenon happens,affecting the normal progress of the electrochemical reaction,and ultimately leading to battery failure.In response to the above problems,this paper used a carbon nanocomposite conductive agent and added it to the negative electrode active material.The study found that compared with the blank battery,the mass ratio of the carbon black and graphene composite material is 1:3 in carbon nanocomposite conductive agent,its C₂₀ increases from with an increase of 9.3%;the charge acceptance increases from 4.04 to 8.91 with an increase of 120.5%;the high current discharge time increases from 0.469 h to 0.544h with an increase of 16.0%;HRPSo C cycle life increases from 2461 times to 7968 times with an increase of 223.8%;the utilization rate of NAM increases from 62.84%to 68.66%with an increase of 9.3%.The reason may be:the three-dimensional conductive network structure constructed by the carbon nanocomposite conductive agent makes the combination of the conductive agent and the lead negative active material more stable and tight,improves the affinity between the carbon material and the negative active material;provides double electricity Layer capacitance effect;increases hydrogen evolution overpotential.In this paper,graphene composite conductive agent are added into NAM,Compared with GNs,the C₂₀ of the battery increases from 4.110 Ah to 4.374 Ah with an increase of6.4%;the charge acceptance increases from 8.33 to 8.91 with an increase of 7.0%;the high current discharge time increases from 0.536 h to 0.544 h with an increase of 1.5%;HRPSo C cycle life increases from 4243 to 7968 times with an increase of 87.8%;the utilization rate of NAM increases from 64.52%to 68.66%with an increase of 6.4%.The reasons may be:graphene composite conductive agent has a higher hydrogen evolution overpotential and specific capacitance value,and has a better affinity with NAM.Adding graphene composite conductive agent to the negative electrode while surface coating of the negative electrode grid with graphene slurry,on the basis of maintaining the original improvement of battery performance,its charge acceptance and high current discharge time further improve.The reasons may be:the graphene coating layer establishes a good electronic interaction between the negative electrode grid and the interface of NAM,and provides an effective electron transmission path from the negative electrode grid to NAM.In this paper,through a series of optimizations on the preparation process of graphene composite materials,the graphene composite conductive slurry was successfully introduced into the model battery production line of Ainos Chongqing Huada Power Co.,Ltd.,and assembled into model batteries(HX410F,12 V/105 Ah),the performance test results of the model battery show that the addition of graphene composite conductive slurry improves the conductivity of the battery,reduces the internal resistance of the battery,increases the 10-hour rate discharge capacity of the battery,and improves the high-power discharge performance and cycle stability of the battery.