Which type of battery cell cannot be recharged?

The correct answer is primary cells. Primary cells are designed for single-use and cannot be recharged after their chemical energy has been depleted. They generate electrical energy through irreversible chemical reactions, which means once the reactants have been consumed, the cell cannot be restored to its original state. Common examples of primary cells include alkaline batteries and zinc-carbon batteries, which are often used in household electronics.

In contrast, NiCad cells and lead-acid batteries are designed as rechargeable options. NiCad (nickel-cadmium) cells are a type of secondary cell that can undergo chemical reactions that allow them to be recharged multiple times. Similarly, lead-acid batteries, which are widely used in automobiles, also fall under secondary cells and can be recharged after discharging. This fundamental difference in the ability to be recharged establishes primary cells as the only type in this context that is not capable of being reused once depleted.