In Depth: Batteries

Many devices, such as mobile phones, laptops, tablets, and embedded devices, require batteries. Batteries, at a basic level, are liquids stored in a container. The liquid is a chemical that has the energy within it converted into electricity, transferred from the negative end through a circuit to the positive end of the battery.

There are two primary batteries in use today: Disposable and Reusable. Disposable or alkaline batteries are typically made of zinc and carbon, where magnesium reacts with the zinc to create a charge. Rechargeable batteries, such as lithium-ion, lead acid, and nickel-cadmium, can be recharged multiple times.

With computers, the most common type of battery used is lithium-ion. Lithium comes from four central countries: Australia, Chile, China, and Argentina.

The dangers of batteries range depending on the type of material that is contained in the battery.  Alkaline batteries are mild irritants to humans, primarily due to potassium hydroxide caused when a battery leaks. The danger to electronics is that the potassium hydroxide will continue spreading to other circuits, oxidizing and permanently damaging them. They are toxic to the environment.

Lead Acid batteries are dangerous in many ways. The acid itself is a significant irritant to humans. It can also produce hydrogen and oxygen gas that is explosive. Lastly, lead is highly toxic to humans as it can be absorbed into the bloodstream and interfere with enzyme functions of the body.

Lithium batteries are probably the least toxic to humans but are much more dangerous in a different way: extremely flammable. Lithium combines with oxygen in a very explosive nature, causing fires that cannot be put out. This is why lithium batteries are now marked on boxes very apparently and not allowed to be stored unpressurized. If a small crack in the casing occurs, it will immediately ignore. Additionally, it produces a lot of heat upon use, leading to a thermal runaway situation where the battery gets too hot to stop producing heat energy, causing the casing to crack and allowing the lithium to react with oxygen.

Overall, the main thing to understand about batteries is that they are instrumental but very dangerous to humans and the environment. Treat them well, and don't play with them.