What is lithium iron battery? Introduction to working principle and advantages of lithium iron battery

Lithium iron battery is a kind of battery in the lithium battery family. Its full name is lithium iron phosphate lithium ion battery. The cathode material is mainly lithium iron phosphate. Because its performance is particularly suitable for power applications, it is also called “lithium iron power battery”. (hereinafter referred to as “lithium iron battery”)

Working principle of lithium iron battery (LiFePO4)
Internal structure of LiFePO4 battery: LiFePO4 with olivine structure on the left is used as the positive pole of the battery, which is connected by aluminum foil and the positive pole of the battery. In the middle is a polymer diaphragm, which separates the positive pole from the negative pole. However, lithium ion Li+can pass through but electronic e – cannot. On the right is the negative pole of the battery composed of carbon (graphite), which is connected by copper foil and the negative pole of the battery. The electrolyte of the battery is between the upper and lower ends of the battery, and the battery is sealed by a metal shell.

When the LiFePO4 battery is charged, the lithium ion Li+in the positive electrode migrates to the negative electrode through the polymer membrane; During the discharge process, lithium ion Li+in the negative electrode migrates to the positive electrode through the diaphragm. Lithium-ion battery is named after the migration of lithium ions during charging and discharging.

Main performance of LiFePO4 battery
The nominal voltage of LiFePO4 battery is 3.2 V, the ending charge voltage is 3.6 V, and the ending discharge voltage is 2.0 V. Due to the different quality and process of positive and negative electrode materials and electrolyte materials used by various manufacturers, their performance will be somewhat different. For example, the battery capacity of the same model (standard battery in the same package) is quite different (10%~20%).

Advantages of lithium iron battery
Compared with traditional lead-acid batteries, lithium-ion batteries have significant advantages in working voltage, energy density, cycle life, etc. Compared with the traditional lead-acid battery, it has the following advantages: high energy density, strong safety, good high temperature performance, high power output, long cycle life, light weight, saving machine room reinforcement cost, small size, long battery life, good safety, etc.