PURPOSE: To enlarge the vertical length of each mesh by enlarging the maximal amount of expansion at the time of expanding a lead alloy made thin plate through heating the lead alloy made thin plate at a specified temperature not exceeding a temperature capable of recrystallizing it and then subjecting it to expanding operation.
CONSTITUTION: A plurality of parallel slits 3 each having a length K are formed, in a zigzag manner, in a lead alloy made thin plate 2 whose grating 1 contains no antimony or only a small amount of antimony if any, in the horizontal direction thereof. The thin plate 2 is expanded orthogonally to the slits 3, thereby being subjected to expanding operation. In this case, after heated at a specified temperature not exceeding a temperature capable of recrystallization of the thin plate 2, this thin plate is expanded, by which the maximal amount of expansion at the time of expanding the thin plate 2 becomes large. As a result, the vertical length of each mesh 4 becomes large. This makes low the electrical resistance of the mesh gratings so as to facilitate the takeout of a large current necessary at the time of, for example, an engine start.
Mizutani Soumi
Kazunobu Sawada
Satoshi Kamio
Koichiro Hara
Masatoshi Miwa