batterie

Batterie comes from Old French batre (to beat, to strike), from Latin battuere. A battery in military usage was a group of artillery pieces — cannons arranged together for coordinated fire. The word is about striking, not storing. A battery of cannons struck the enemy. The word named the action and the arrangement.

Benjamin Franklin borrowed the word in 1749. He had arranged multiple Leyden jars — early capacitors — in a row, connecting them to increase their combined charge. The arrangement reminded him of a battery of cannons: multiple units lined up, each contributing its power to the whole. He called it a 'battery' of jars. The analogy stuck. The word migrated from artillery to electricity because one scientist saw a resemblance.

Alessandro Volta built the first true electrochemical battery in 1800 — the voltaic pile, a stack of zinc and copper discs separated by brine-soaked cloth. This device produced continuous electrical current, unlike the Leyden jar's single discharge. Volta's pile was a battery in Franklin's sense: multiple cells arranged in series, each contributing to the total output. The word, the analogy, and the arrangement all held.

Modern batteries power everything from phones to cars to spacecraft. The lithium-ion battery, commercialized by Sony in 1991, stores energy in the movement of lithium ions between electrodes. A Tesla car battery contains thousands of individual cells — a battery of cells in the original military sense of 'an arrangement of units for combined action.' Franklin's metaphor has held for 275 years.