In today’s increasingly mobile world, we rely heavily on innovations that allow us to move with our gadgets. Perhaps no other technology gives us as much mobility as the smartphone. It’s a small device that fits in our palms and appears to have all the information we could ever want.

What our minds seem to forget about smartphones is that they would not be possible without the presence of a battery. The tiny cylinders—or thin blocks in the case of most smartphones—carry all of the moving electrons needed to power all of the tiny pocket computers that allow us to check the time or message a friend that we should meet somewhere else.

Many people are unaware of the underlying processes that give batteries their purpose; many people will go through many phones in their relentless pursuit of the latest in smartphone technology, all without ever figuring out what goes on inside. Wait no longer—Modern Sciences has you covered.

In its most basic form, a battery is an electrochemical device that converts chemical energy into electrical energy. It is made up of one or more electrochemical cells. Each cell has a cathode (a positive electrode), an anode (a negative electrode), and an electrolyte. The electrodes are usually made of metals or metal compounds, and the electrolyte is a chemical solution that allows ions to flow between the electrodes. The key point here is that all systems are in some way in contact with one another, allowing electrons and ions to move between them depending on where they are in the process.

When a battery is connected to a circuit, like a smartphone, a chemical reaction happens at the electrodes. During this reaction, electrons move from one electrode to the other. Positive ions move in the opposite direction as a sort of balance, moving between electrodes via the electrolyte. This means that while positive ions move around inside the battery, electrons go the other way, forcing them to pass through the device that requires them for power.

When you charge a battery, however, the opposite occurs. When there are more electrons than ions, the ions move in the opposite direction, reversing the electrochemical reaction and returning both electrons and ions to the original electrode. This “resets” the electrochemical reaction, allowing the battery to discharge once more. The possibilities are almost limitless from there; changing a battery’s properties, such as the amount of charge it can hold and the rate at which it charges and discharges, is simply a matter of modifying the materials and systems that comprise a battery. This is why there are various types of batteries available, ranging from the massive boxes used to start gas-powered cars to the thin, polymer-covered ones found at the back of your nearest mobile screen with a selfie camera.

Changing the properties of a battery, such as how much charge it can hold and how quickly it charges and drains, is as simple as changing the materials and systems that comprise it. Because of this, there are many different kinds of batteries, from the big boxes used to start gas-powered cars to the thin, polymer-covered ones on the back of your phone screen with a selfie camera.

Overall, batteries make our technology less limited than it would be if everything had to be wired and plugged into the power grid. This gives us a lot more freedom to experiment with how and where we can use these new tools and devices.

References

• Bertrand, G. (n.d.). About Batteries. Battery; Missouri University of Science and Technology. Retrieved 18 January 2023, from https://web.mst.edu/~gbert/BATTERY/battery.html
• Bhatt, A., Forsyth, M., Withers, R., & Wang, G. (2016, February 25). How a battery works. Australian Academy of Science; Australian Academy of Science. https://www.science.org.au/curious/technology-future/batteries
• Northwestern University. (n.d.). How do batteries work? Power System; Northwestern University. Retrieved 18 January 2023, from https://www.qrg.northwestern.edu/projects/vss/docs/power/2-how-do-batteries-work.html