A primary battery or primary cell is a battery (a galvanic cell) that is designed to be used once and discarded, and it is not rechargeable unlike a secondary cell (rechargeable battery). In general, the electrochemical reaction occurring in the cell is not reversible, rendering the cell unrechargeable. As a primary cell is used, chemical reactions in the battery use up the chemicals. In the early twenty-first century, primary cells began losing market share to secondary cells, as relative costs declined f. Secondary cells () are in general more economical to use than primary cells. Their initially higher cost and the purchase cost of a charging system can be spread out over many use cycles (between 100 an. A major factor reducing the lifetime of primary cells is that they become polarized during use. This means that accumulates at the cathode and reduces the effectiveness of the cell. To reduce the effects of polariz.