6F22 carbon battery.Detailed explanation of mobile phone battery technology: Why do lithium batteries catch fire?

　　Lithium batteries are the most common type of battery because they can store the most power in the smallest space. This needs to be measured by energy density, which is the amount of electricity that a battery can store per kilogram, measured in watt hours (wh). Lithium-ion batteries are smaller and lighter than other battery types, allowing them to shrink the size of your device while still maintaining long battery life.

　　The author compiled an article from the American IT website PCWorld, which elaborates on the principles, defects and future development trends of lithium batteries used in mobile devices.

　　chemical principles

　　The batteries used in mobile devices are a masterpiece of chemical engineering: storing a large amount of power in a small cube can keep the mobile device running for many hours. How does it work? How can we get the most out of it?

　　Most modern mobile devices use lithium batteries, which mainly contain two parts: a pair of electrodes and an electrolyte that exists between them. There are many kinds of electrode materials, which can be lithium, graphite, or even nanowires, but without exception they all rely on the chemical component of lithium. It is a reactive metal and therefore easily synthesized with other elements. Pure lithium is extremely reactive and can even spontaneously ignite in the air, so most batteries use safer lithium cobalt oxide.

　　Between the two electrodes is an electrolyte, usually a liquid organic solvent, that allows electrons to flow through it. When a lithium battery is charged, lithium cobalt oxide molecules can capture electrons and then release them during battery use to support the operation of the phone.

　　Lithium batteries are the most common type of battery because they can store the most power in the smallest space. This needs to be measured by energy density, which is the amount of electricity that a battery can store per kilogram, measured in watt hours (wh). The energy density of lithium batteries is generally between 150 and 250 Wh/kg, while the nickel-metal hydride battery is only 100 Wh/kg. In other words, lithium batteries are smaller and lighter than other types of batteries, allowing them to shrink the size of a device while still maintaining long battery life.

　　The above chemical process can be summarized as follows: the battery in the device stores electricity, and then the chemicals inside release the electricity in any possible way. But there are also problems. For example, the battery of the latest Boeing 787 Dreamliner will catch fire when the plane is parked.

　　This is one of the flaws of lithium batteries: if the battery is over-discharged, the chemicals inside will decompose and generate excess lithium oxide, which will burn and generate more lithium oxide, and so on. Chemists call it "thermal runaway," which ordinary people see as a fire. This is why the Boeing 787 is grounded by the U.S. Special Administration (FAA). Because the same thing can happen when a battery is punctured, U.S. transportation The TSA recommends that airline passengers carefully stow batteries in carry-on luggage rather than checking them in.

　　battery capacity

　　The unit of battery capacity is milliampere hours (mAh), which represents the overall power that a battery can provide. For example, if a battery has a capacity of 1000 mAh, it can continuously supply 1000 mA of current for one hour. If your device draws 500 mA, then this battery will last about 2 hours.

Read recommendations:

18650 1200mAh 3.7V

Polymer lithium battery expansion

What is the difference between lithium battery protection board and BMS (battery management system)?

solar energy storage lithium ion battery 15kwh 48v 100ah

18650 battery rechargeable