For the first time, the effects of designed siloxane derivative N-triethoxysilylpropyl 3,4,5-tris(tetradecyloxy) benzamide (Compound 1) as an electrolyte additive on the electrochemical properties of gelled electrolyte valve-regulated lead-acid (VRLA) battery were investigated. Results show that Compound 1 decreased gelled electrolyte resistance and possibly triggered the formation of large inorganic crystals due to the poly-condensation reaction. In addition, the hydrogen evolution process was inhibited and the stability of gelled electrolyte by the experiment of released liquid was significantly improved by addition of Compound 1. (C) 2010 Elsevier Ltd. All rights reserved.