Abstract: The present invention pertains to current limiting (overcurrent protection) header assemblies which employ a Positive Temperature Coefficient (PTC) device. More particularly, this invention pertains to current limiting header assemblies which employ a PTC device and which have particular design features, specifically, a dimpled support plate and an apertured PTC plate positioned above the dimpled support plate, wherein the dimple protrudes into or through the aperture. The header assemblies are useful in battery cells, particularly in battery cells which employ a glass-to-metal, plastic-to-metal, and similar seal instead of a stacked and crimped design. The header assemblies are compact, effectively taking up only a little more thickness than would be required for just an end cap, permitting the use of more electroactive materials and thereby yielding a battery with increased energy density.