Preparation Of Carbon Materials With Lead Coating And Study Of Zinc-Cerium Battery Application

The open circuit voltage of zinc-cerium single battery is as high as2.4V, which is more than2times of all-vanadium flow batteries’electromotive force, the performance of the electrode won’t be deteriorateby cross contamination of positive and negative liquid electrolyte thatwhich is only reduce the current efficiency of the battery. Zinc-dendritemaybe produced on the cathode in the process of charging and the ionexchange membrane would be punctured which lead to rapid decline ofbattery if zinc-dendrite growth continuously.Zinc-dendrite developing oncathode can be inhibited and the coulomb efficiency will be improvedthrough modified cathode material and optimize electrolyte compositionand content.In this paper, influence factors on Cu clad layer morphology andadhesion from the carbon material(C-PVDF) substrate electroless copperplating pretreatment has been studied.The uniformity of copper depositscan be improved by alkaline degreasing.The results of caloric test,contactangle test and polarized light microscopy imaging reveal that chemicaland mechanical coarsening can improve the hydrophilicity on the surfaceof the substrate and the adhesion strength of the coating.Anode and cathode processes of electroless copper plating based onthe theory of mixed potential have been studied.The results show thatboth processes have been affected by temperature and pH value ofelectroplating solution.Current density of anode and cathode reaction canbe increased if raise electroless plating temperature.Ocularestimate,desiccant method and polarized light microscopy imaging resultsindicate that Cu plating coat can not be obtained on the surface ofC-PVDF when the temperature of the plating solution is lower than20℃and raise temperature can accelerate the copper deposition.But the platingsolution will be decomposed if the temperature is above50degreesCelsius.Hence that the best plating temperature is30～40℃.Thedeposition rate of copper would be improved if raise the pH of solution.Itcan be get a plating layer exhibited smooth and bright bronze color whilethe solution pH in the range of12～13.However,quality of Cu-coatingwould be deteriorated and plating solution be lead to decomposed if the initial pH of electroless plating solution is higher than13.The results of constant current electrodeposition technology andpolarized microscopic analysis indicate that lead deposition morphologyand adhesion have been significantly improved by adding additives inplating electrolytes with tartrate.Smooth and glossy lead clad layer withsilver metallic luster can be prepared while the concentration of additivesis one gram per liter.But the lead coating would be deteriorated if theconcentration of additives is excessive.Influencing factors of zinc electro-deposition morphology oncathode of methanesulfonic acid zinc-cerium battery have been studied inthis paper.The consequences of galvanostatic charge experiments showedthat zinc electro-deposition morphology have a close relationship with thecomposition of cathode electrolyte and cathode materials.The formationand growth of zinc dendrite can be restrained effectively on account oftrace amounts of sulfamic acid or urotropine in cathode electrolyte.Butappearance quality of zinc coating be deteriorated by reason of excessiveadditives.Results of polarized light microscopy analysis demonstratedthat the quality of zinc electro-deposition morphology on C-PVDF withlead coating is better than other carbon materials.Therefore,the reliabilityof battery operation can be get improved by using C-PVDF with leadcoating as cathode.In this paper, the influence factors of methyl sulfonic acid zinccerium batteries’ coulomb efficiency have been sdudied via galvanostaticcharge-discharge experiments. Coulomb efficiency is from88％to90％while the concentration of free methyl sulfonic acid and active materialssuch as zinc ion is1.5and1.0～1.5moles per liter respectively incathode electrolyte. Coulomb efficiency reach up to94.0％and93.1％by apply lead sheet and C-PVDF with lead coating to cathode ofzinc-ceium battery.