Which type of battery is characterized by fine, highly porous, micro-fiber glass separators?

The type of battery characterized by fine, highly porous, micro-fiber glass separators is the Absorbed Glass Mat (AGM) battery. AGM batteries utilize special glass mat separators that are designed to absorb and hold the electrolyte, making them highly efficient and less prone to spillage. These separators allow for a very low resistance, contributing to the quick recharge capabilities and excellent power delivery of AGM batteries. This unique structure also helps in preventing internal short circuits and provides better performance in various temperatures compared to other types.

In contrast, lead-acid batteries typically use liquid electrolyte and have different separator materials, which do not provide the same benefits as those found in AGM batteries. Gel-cell batteries use a gel-type electrolyte, which doesn’t involve the same porous glass mat structure. Ni-Cad batteries consist of nickel and cadmium, with their design focusing on a different battery chemistry and separator technology that does not include micro-fiber glass. Therefore, the distinguishing feature of AGM in this context is its innovative use of micro-fiber glass separators, making it the correct answer.