The performance of a silica-based mixed gel electrolyte in lead acid batteries

The gel electrolyte is a key factor affecting the performance of lead-acid batteries. Two conventional gelators, colloidal and fumed silica, are investigated. A novel gel electrolyte is prepared by mixing the gelators with sulphuric acid. The physical property testing demonstrates that the mixed gel electrolyte is more mobile, has a longer gelling time, greater stability and a better crosslinking structure than its counterparts as compared with any single gelling agent. The electrochemical properties indicate that the mixed gel electrolyte can suppress the oxygen evolution reaction, reduce the resistance to charge transfer at open circuit potential, increase the initial capacity, demonstrating that it is a promising gel electrolyte for lead acid batteries.

► The viscosity of the new gel electrolyte was significantly improved.
► A longer gelling time was indicated in the novel gel.
► The mixing of two gelators can inhibit the oxygen evolution reaction.
► The initial capacity is increased by twenty percent in the gel battery with mixed gel electrolyte under the same conditions.
► When gelling agents are mixed in a certain proportion, an appropriate three-dimensional gel structure is formed, entrapping more sulfuric acid electrolyte.