| The development of physical and d emical power sources trades is being promoted by the continue and rapid development o~?c iinese economy.It has a bright future because of many advantages of valve-regulated Lead/Acid battery(VRLAB),But VRLAB has many problems to be conquered in the applied fields,for example:premature capacity loss ,thermal-run away, water loss, positive grid corrosion, sulfation of the negative plates, high sei-discharge rate, capacity decay on cycling, low formation efficiency, low specific energy etc.al. Many men are trying to overcome these shortcomings of VRLAB from the different ways,and a number of recognitions or achievements have been gained. We mainly studied the methods of how to improve the performance of VRiJAB in this thesis. Barium metaplumbate, a conductive ceramic having the pervoskite, is relatively stable in sulfuric acid. It抯 influnce to plates formation efficiency~ active materials utility and cycle life of VRLAB was studied when Larium metapluinbate was added in positive or negative active materials as a additive. The micro-structure and phase composition of positive active materials were studied on the different stages during cycle process with the aid of SEM and XRD. First, Barium metaplumbate was synthesized using a mixture of regent grade Barium oxide~ Barium nitrate and lead nitrate lead tetroxide at 72OC in 2 hours under a stream of atomosphere or oxygen. Elements content of Barium metaplumbate was ana~ised througn analytical chemisiry method. The material thus synthesized was identified as BaPbO3 and ha~ a higher purity,whole crystal structure and well-distributed crystal pellet by XRD and SEM. The effect of different loading profortions of BaPhO3 in positive or negative active materials on the battery performance indicated: it can effectively enhance tu eplates formation efficiency and active materials utiiity, this is related with higher electric conductive of itself. The formation mechanism is changed when the condutive particles are dispersed in ~he plate. Formation not only proceeds form the grid toward the center of the pellet but also slowly around the conductive particles in the plate. The conductive paths of Pb02 or Pb grow and make connection with each other during formation to establish a network which further facilitates the formation. These properties make this compound an attrative additive in iead/ acid batte-ry for the enhancement of formv don efficiency and active materials utility. We also studied the cycle life of VRLAB while the loading of BaPbO3 was 1% of the paste weight in positive or negative active materials. The results indicate: the failure process of VRLAB's cycle life is accelerated with addition of BaPbO3 in positive plates, the life performance of VRLAB is imp-roved with addition of BaPbO3 in negative plates. The influnces of impurity and water loss on VRLAB performance were eliminated through the analysis of experament process and results. The change of micro-structure and materialscomponeut of positive active materials in differe-nt stages during cycle process is the main reason which causes the failure of VRLAB form SEM photos and XRD figures. The experament of discomposition of BaPbO3 at 70~C in sulfuric acid showed that Barium metaplumbate is unstable in higher tempreture in sulfuric acid and easily decomposed which caused the rapid failure of VRLAB? s cycle life. Therefor arium metaplumbate has benifitial to the enhancement of formation efficiency and active materials utility, but it has the best loading proportion for the cycle life of VRLAB, and this is the prospect... |
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