Lithium is a metal element with a chemical symbol of Li (English name is lithium). It is a silver-white, very soft, chemically active metal that is the lightest in metals. In addition to its application in the atomic energy industry, it can manufacture special alloys, special glass (fluorescent screen glass for TV sets) and lithium batteries. It is used as an anode of a battery in a lithium battery.
The lithium battery has the advantages of stable discharge voltage, wide operating temperature range, low self-discharge rate, long storage life, no memory effect and no pollution.
Lithium batteries are also divided into two categories: non-rechargeable and rechargeable. A non-rechargeable battery is called a disposable battery. It can only convert chemical energy into electrical energy at one time, and cannot restore electrical energy back to chemical energy (or very poor recovery performance). A rechargeable battery is called a secondary battery (also called a battery). It converts electrical energy into chemical energy and, when used, converts chemical energy into electrical energy. It is reversible, such as the main feature of lithium-ion batteries for electrical energy.
Smart portable electronic products require a small size and light weight, but the size and weight of the battery are often the largest and heaviest compared to other electronic components. For example, the "big brother" of the year is quite "big and heavy", and today's mobile phones are so light. Among them, the improvement of the battery plays an important role: in the past it was a nickel-cadmium battery, and now it is a lithium-ion battery.
The biggest feature of lithium batteries is their high specific energy. What is specific energy? Specific energy refers to energy per unit weight or unit volume. The specific energy is expressed in Wh/kg or Wh/L. Wh is the unit of energy, W is watt, h is hour; kg is kilogram (weight unit), and L is liter (volume unit). Here is an example to illustrate: the No. 5 nickel-cadmium battery has a rated voltage of 12V and its capacity is 800mAh, and its energy is 096Wh (12V×08Ah). The same size of the No. 5 lithium-manganese dioxide battery is rated at 3V, and its capacity is 1200mAh, and its energy is 36Wh. The volume of these two batteries is the same, the specific energy of the lithium-manganese dioxide battery is 375 times that of the nickel-cadmium battery!
A No. 5 nickel-cadmium battery weighs about 23g, while a No. 5 lithium-manganese dioxide battery weighs about 18g. One lithium-manganese dioxide battery is 3V, and two nickel-cadmium batteries are only 24V. Therefore, when the lithium battery is used, the number of batteries is small (the portable electronic product is reduced in size and weight), and the battery has a long working life.