What major factor differentiates a wet-cell battery from a dry-cell battery?

A wet-cell battery is characterized primarily by the use of a liquid electrolyte, which distinguishes it from a dry-cell battery that employs a paste or solid electrolyte. The liquid electrolyte in a wet-cell allows for the movement of ions, facilitating the chemical reactions necessary for electricity generation. This design often results in higher capacity and the ability to deliver high current over an extended period, making wet-cell batteries suitable for applications requiring significant power, such as automotive batteries.

In contrast, dry-cell batteries are sealed units with a non-liquid electrolyte, making them more convenient and portable. This configuration generally leads to a lower maximum discharge rate compared to wet cells. The aspects of electrode type, battery size, and voltage output can vary across both types of batteries and do not serve as distinguishing factors between them. Therefore, the presence of a liquid electrolyte is the key feature that sets wet-cell batteries apart from their dry-cell counterparts.