Home >> News
At present, power batteries mainly include lithium iron phosphate batteries, lithium manganate batteries and ternary lithium batteries. The lithium iron phosphate battery supports half of the lithium ion battery material industry. What is the working principle of the lithium iron phosphate battery? Next Lithium Iron Phosphate Battery Manufacturer will come to tell you.
The positive electrode of the lithium iron phosphate battery is composed of LiFePO4 with an olivine structure, the negative electrode is composed of graphite, and the middle is a polyolefin PP / PE / PP separator.
During charging, lithium ions are de-intercalated from the positive electrode through the electrolyte into the negative electrode. At the same time, electrons are moved from the positive circuit to the negative electrode from the external circuit to ensure the charge balance of the positive and negative electrodes. During discharge, lithium ions are de-intercalated from the negative electrode and inserted into the positive electrode through the electrolyte. The charging and discharging voltage platform of the lithium iron phosphate battery is long and stable. The lithium iron phosphate battery shows good cycle stability during charging and discharging, and has a long cycle life.
Lithium-Ion Battery Energy Storage System
So what are the advantages of lithium iron phosphate batteries?
Lithium Iron Phosphate Battery has won the trust of many manufacturers due to its low price and strong security. The positive electrode material in lithium-ion batteries accounts for more than 40% of the total battery cost. Under the current technical conditions, the energy density of the overall battery mainly depends on the positive electrode material. Therefore, the positive electrode material is the core development and research material for lithium-ion batteries, and is currently mature. Applied cathode materials include lithium cobaltate, lithium nickel cobalt manganate, lithium iron phosphate, and lithium manganate.
1. Lithium cobaltate
There are layered structure and spinel structure. Generally, layered structure is commonly used. The layered structure of lithium cobaltate is mainly used in digital products such as mobile phones, aircraft models, car models, electronic cigarettes, and smart wear. At present, the energy density and compaction density of lithium cobaltate have basically reached the limit. Compared with the theoretical capacity, there is still a large room for improvement. However, due to the limitations of the current overall chemical system, especially the electrolyte system at high voltage It is easy to decompose, so the method of further increasing the specific capacity by increasing the charge cut-off voltage is subject to certain restrictions. Once the subsequent breakthrough in the electrolyte technology, there will be room for improvement in its energy density.
2. Nickel cobalt cobalt manganate
The current research on single crystal nickel cobalt cobalt manganate mainly improves the energy density of the product by continuously increasing the nickel content and increasing the charge cut-off voltage. Capabilities put forward higher requirements.
3. lithium manganate
There are spinel structure and layered structure, spinel structure is commonly used. It has the characteristics of better capacity, stable structure, superior low temperature performance and low cost. However, its crystal structure is easily distorted, resulting in capacity attenuation and short cycle life. It is mainly used in some markets with higher safety requirements and high cost requirements, but lower energy density and cycle requirements. Such as small communication equipment, power bank, power tools and electric bicycles, special scenarios (such as coal mines).
4.lithium iron phosphate
Generally has a stable olivine skeleton structure, the discharge capacity can reach more than 95% of the theoretical discharge capacity, excellent safety performance, good resistance to overcharge, long cycle life, and low price. Lithium iron phosphate cathode material shows good thermal stability, safety and reliability, low carbon and environmental protection when applied. It is the first choice cathode material for Lithium-Ion Battery Energy Storage System.
The above is the working principle and advantages of lithium iron phosphate .