摘要 |
<p>A recombinant lead acid battery separator formed of a PTFE fibril matrix and a particulate, amorphous silica filler enmeshed in the PTFE matrix. The separator has a tensile strength greater than 0.5 MPa, a bulk density lower than about 0.40 gram/cc and a void volume greater than about 75%. The separator is made by mixing together PTFE and a non-evaporative lubricant, adding amorphous silica during mixing, continuing mixing until a material having a dough-like consistency is obtained, removing the dough-like material and calendering it to form a sheet, removing from about 95% to about 100% by weight of the non-evaporative lubricant from the sheet by solvent extraction, and drying the extracted sheet.</p> |