SEPARATOR FOR A SEALED LEAD-ACID BATTERY, AND SEALED LEAD-ACID BATTERY

摘要

The disclosed separator for a sealed lead-acid battery comprises a sheet that is based on fine glass fibers and formed by a wet process. Said sheet is a three-layer structure in which two fine-fiber layers cover the two surfaces of one thick-fiber layer in the thickness direction of the separator. Each fine-fiber layer has a mean pore diameter of at most 3.5 µm and comprises fine glass fibers with a mean diameter between 0.4 and 1.0 µm. The thick-fiber layer, which comprises fine glass fibers with a mean diameter between 1.3 and 4.0 µm, has a mean pore diameter that is at least 4.0 µm and at least 1.5 times that of the fine-fiber layers. Across all three layers, the mean glass fiber diameter is at least 1.2 µm and the ratio of the thickness of the fine-fiber layers to that of the thick-fiber layer is between 10/90 and 50/50. This configuration makes it possible to simultaneously improve prevention of electrolyte stratification and prevention of compressive force losses in a sealed lead-acid battery, and electrolyte mobility inside the separator is improved.