Page 334 - Handbook of Battery Materials
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304 11 Separators
For problem-free processing, high tensile and puncture strengths are desirable.
Especially when using expanded metal electrodes, sharp edges or points which
may puncture the backweb and lead to shorts have to be taken into account. Even
though the polyethylene separator is unique in these properties compared with
conventional separators, these are considerable differences between the products
of various suppliers.
11.2.2.1.4 Profiles The standard profile for microporous pocket separators
exhibits continuous longitudinal ribs 10–12 mm apart, which determine the total
thickness (Figure 11.12). The margin area, used later for the welding process,
generally has ribs of lower height (Figure 11.13) or only a thicker backweb. These
measures facilitate the mass distribution in calendering during the production
Figure 11.12 Polyethylene separator: pockets.
Figure 11.13 Polyethylene separator: standard profile.
