A valve-regulated lead-acid battery of this invention includes: an
electrode plate group; and an electrolyte impregnated into and retained
by the electrode plate group. The electrode plate group includes:
positive electrode plates that each include a positive electrode current
collector comprising a Sn-containing lead alloy, and a positive electrode
active material retained by the positive electrode current collector;
negative electrode plates that each include a negative electrode current
collector comprising a lead alloy, and a negative electrode active
material retained by the negative electrode current collector; and
separators. The Sn content in the positive electrode current collector is
1.1 to 3.0% by mass, and the pore volume per unit mass of the negative
electrode active material is 0.115 to 0.150 cm.sup.3/g.By employing the
above configuration, the negative electrode plate has a stable
oxygen-absorbing ability, and the corrosion of the current collector of
the positive electrode plate is suppressed, so that it is possible to
obtain a valve-regulated lead-acid battery with a stable long life.