We’ve all been there: our phone dies in the middle of a call or our camera shuts off just as the perfect shot presents itself. In these moments, it’s easy to feel frustrated with our batteries. But have you ever stopped to consider the science behind these marvels of modern technology?
Batteries are an essential part of our daily lives. They allow us to use our smartphones, laptops, and countless other devices without being tethered to a power outlet. But even the best batteries will eventually lose their charge and die. So why does this happen, and how do batteries even store so much energy in the first place?
The story of the battery begins in the 1780s with two Italian scientists, Luigi Galvani and Alessandro Volta. Legend has it that Galvani discovered “animal electricity” while studying a frog’s leg. He believed that a type of electricity was stored in the very stuff of life. However, Volta disagreed, arguing that it was the metal itself that made the leg twitch.
To settle the debate, Volta conducted an experiment using a stack of alternating layers of zinc and copper, separated by paper or cloth soaked in a salt water solution. This created a flow of electrons between the two substances, powering anything connected to the circuit. This principle is still used in modern batteries today.
Over time, batteries lose their charge as the metal inside oxidizes. Rechargeable batteries offer a temporary solution to this problem by allowing the oxidation-reduction process to be reversed. However, even rechargeable batteries have a finite lifespan. The repetition of the oxidation-reduction cycle causes imperfections and irregularities in the metal’s surface, preventing it from oxidizing properly. Eventually, the electrons are no longer available to flow through the circuit, and the battery dies.
But the future of batteries is looking bright. Scientists are working on developing light, thin sheets that operate on the principles of quantum physics and can last for hundreds of thousands of charge cycles. Until then, plugging your charger into the wall remains the best way to forestall that fatal “bleep”.