Physics · Ch 2 — Current Electricity
Electric Cells and Batteries
Electric Cells and Batteries
An electric cell converts stored chemical energy directly into electrical energy. A simple example (Figure 2.17) uses two dissimilar electrodes -- carbon (positive) and zinc (negative) -- immersed together in a sulfuric-acid electrolyte; the chemical reactions between the electrodes and the electrolyte set up a potential difference between the two terminals. When several such cells are connected together, the combination is called a battery (Figure 2.18 shows a range of commercially available cells and batteries). Whenever a cell or battery is connected into a circuit, electrons flow from its negative terminal, around the external circuit, to its positive …
What this figure shows. A single glass container filled with a sulfuric-acid electrolyte, with a carbon electrode marked as the positive (+) terminal and a zinc electrode marked as the negative (-) terminal, each electrode connected to its own external terminal wire -- the classic 'wet cell' construction used to introduce how a chemical cell physically produces a potential difference betwe …
What this figure shows. A photograph-style illustration of several commercially available electric cells and batteries of different shapes and sizes -- ordinary cylindrical dry cells, a rectangular multi-cell battery and a button cell among them -- showing the everyday, real-world variety of devices that all work on the same basic chemical-to-electrical en …