An expert panel replies to questions on lead-acid technology and performance asked by delegates to the Ninth Asian Battery Conference. The subjects are as follows. Grid alloys: effects of calcium and tin levels on microstructure, corrosion, mechanical and electrochemical properties; effect of alloy-fabrication process on mechanical strength and corrosion resistance; low dross-make during casting of lead-calcium-tin alloys; future of book-mould casting; effect of increasing levels of silver-, stability of continuously processed grids at high temperature. Negative-plate expanders: function of lignosulfonates and barium sulfate: benefits of pre-blended expanders, optimum expander formulations. Valve-regulated batteries: effect of oxygen cycle; optimum methods for float charging; charging and deep-cycle lifetimes; reliability testing.