含4BS添加剂的VRLA电池循环寿命机理研究

Study on cyclic life mechanism of VRLA batteries containing 4BS additive

阀控式铅酸蓄电池的安全可靠性高,成本低,但其循环寿命短。以4BS晶种用作电池正极添加剂,可显著提高电池的放电容量和循环寿命。笔者在12 V 2.3 Ah电池的正极板铅膏配方中添加4BS晶种(4BS晶种在铅膏所占质量分数为1%),使其1C高倍率放电性能提高4.2%,循环寿命也得到延长。添加4BS晶种的正极板以α-PbO2形成的多孔骨架混合结构为主,更加利于H+、SO42-和水分子的迁移。电池充放电循环时,正极板发生α-PbO2先转化成PbSO4,再到β-PbO2的演变过程。电池循环寿命失效,本质上是正极活性物质(PAM)的多孔骨架结构逐渐消失,伴有不可逆硫酸盐化,导致板栅腐蚀、内阻增大、寿命终止。

The valve-regulated lead-acid batteries had high safety and low cost, but the cycle life was short. By using 4BS seed as additive, the capacity and cycle life of battery could be significantly improved. In this study, 12 V 2.3 Ah batteries were made by adding 1% 4BS seed. Its 1 C high rate discharge performance was improved by 4.2 %, and its cycle life was also prolonged. In the positive plate of 4BS seed battery, the porous skeleton mixed structure formed by α-PbO2 was the main morphology, which was more conducive to the migration of H+, SO42- and water molecules. During the charge-discharge cycle, the evolution of α-PbO2 into PbSO4, then to β-PbO2 took place in the positive plate. Cyclic life failure of batteries was due to the gradual disappearance of PAM porous skeleton structure and the irreversible sulfation, which lead to corrosion of grids, increase of internal resistance and termination of life.