| Zinc/silver reserve batteries have high energy density, high specific power,excellent low-temperature performance and reliable discharge characteristics, thesemake it employed in many fields, especially was widely used in the militaryequipment. To ensure the zinc/silver reserve battery’s high positive material of activeand negative electrode, there have already produced two formula of negative andpositive electrode, the chemical and electrode-position zinc negative electrode, andthe chemical and pressed silver peroxide positive electrode. Zinc oxide was the zincelectrode’s discharge products; during discharge process, its conductivity graduallybecomes worse. The higher temperature of electrolyte which from the large currentdischarge process can partially mitigate the negative impact of poor conductivity,however, to ensure the stability of the zinc anode, we often joined other inertconductive or conductive metal zinc powder into the zinc negative. If the chemicalsilver peroxide electrode was utilized into the zinc/silver reserve batteries, it must bewashed and dried, then the silver peroxide would be partly decomposition, and thecapacity would be reduced, so developed the battery level’s silver peroxide whichprocess high-purity, high activity, high stability performance, It was particularlyimportant for the development of new zinc/silver battery reserve.In this article, we mainly did two aspects of work that was prepared high-puritysilver peroxide and nano-silver which applied in zinc/silver reserve batteries.(1) Weresearched a suitable method for zinc/silver reserve battery which it produced a kindof high-purity silver peroxide. In the use of potassium peroxide’s strong oxidizingcharacteristics in low temperature, rapidly mixed potassium peroxide solution andsilver nitrate solution, and then adding chemical equilibrium agents known aspotassium or pH adjustment agent. This process avoiding the solid-liquid reactionbetween silver hydroxide, silver oxide and potassium persulfate ions, increasing theliquid-liquid reaction between silver ions and potassium persulfate ions, thenimproved the final product silver peroxide’s purity. The influenced factors were seriously discussed.(2) The preparation process of nano-scale metal silver wasdetailed discussion.(3) Explored the nano-silver doped zinc anode and lithiumbattery cathode’s charge-discharge performance.(4) The silver peroxide and silvernanoparticles’ properties were characterized by use of the SEM, TGA, XRD,experimental battery discharge test techniques and so on. Specific results are asfollows:(1) A certain concentration of silver nitrate solution was warmed to40℃, highspeed stirring, rapidly added twice volume of silver nitrate solution,0.15mol/Lpotassium peroxide, and then got the dark gray of mixture, high-speed stirring,added0.60mol/L potassium hydroxide solution to the gray and black solution, thepH of the solution is controlled between11.0-12.0,maintaining the reaction iscompleted in20minutes, got a black mixture, then the black mixture was leached，washed three times with deionized water,finally got a wet of silver peroxide powder,and dried it in vacuum at60℃for5hours, obtained a particle size of micronmorphology, rod, well distributed particle size, good thermal stability silverperoxide, the purity was nearly100%by the iodometric analysis.(2) We added an appropriate amount of polyvinylpyrrolidone (PVP) or Tween20dispersing agent to the certain concentration of silver nitrate solution at roomtemperature, added0.32mol/L potassium hydroxide, got a red-brown silver oxide sol,respectively used30%hydrogen peroxide,0.32mol/L glucose,0.32mol/L potassiumborohydride as reducing agent, reduction the silver oxide sol, finally got snow-likeappearance, spherical and flake,50-100nm of silver nano-particle. Dispersant did notaffect the silver particle morphology, but it had some influence on particle size. Thesize of nano-silver was relatively small by use of Tween20. Reducer had a greatimpact on the morphology of nano silver powder.(3) Added the nano-silver to the lithium battery cathode materials, the anodedischarge capacity was significantly higher. Using different ways to add silver to thecathode, the resulting discharge capacity was very differently. Added the silver toprecursor material of the positive electrode, the discharge capacity was higher thanthe silver was directly added to the positive electrode material.(4) Added the silver nanoparticles to the positive material of zinc/nickel battery, the zinc anode conductivity increased, the experimental battery discharge voltageand capacity was bigger than no-doped with nano-silver powder of zinc/nickelbattery. |
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