What is lithium ferrous phosphate?



Lithium ferrous phosphate is a new type of lithium-ion battery electrode material, chemical formula: LiFePO4, lithium ferrous phosphate for the recent development of lithium-ion battery electrode materials, mainly used in power lithium-ion batteries, as a positive active material to use, people are accustomed to also call it lithium iron phosphate.

Characteristics and performance of lithium iron(II) phosphate

1, high energy density: its theoretical specific capacity of 170mAh / g, the actual specific capacity of the product has exceeded 150 mAh / g (0.2C, 25 ° C);

2、Safety: it is the safest cathode material for lithium-ion batteries; and it does not contain any heavy metal elements that are harmful to human body.

3, long life: in 100% DOD conditions, can be charged and discharged more than 2000 times, this is the reason that lithium iron phosphate lattice stability is good, lithium ion embedding and disengagement of the lattice is not much effect, so it has good reversibility. The shortcomings are poor electron-ion transfer rate, unsuitable for high-current charging and discharging. In order to apply it to electric vehicles and power tools, people in the material's surface coating conductive materials (mainly carbon), doped with other metal oxides to replace part of the lattice position of Fe, has made the conductivity of lithium iron(II) phosphate has been increased by more than 1 million times. Now, the material made of lithium-ion batteries, can be 10 - 20C or even 30C high current discharge and charging, and discharge performance is excellent).

4, no memory effect;

5, electrical performance, lithium iron(II) phosphate cathode material lithium batteries, you can use a large times the rate of charging, and now the fastest can be in 30 minutes to fill the battery.

Specific physical parameters: (1) loose packing density: 0.8g/cm, (2) vibration density: 1.1 - 1.4g/cm, (3) median particle size: 2.0 - 5.0um, (4) specific surface area <15m/g, (5) coating parameters: LiFePo4:C:PVDF=90:3:7, (6) pole compacted density: 2.1-2.4g/cm

Electrochemical performance: gram capacity>150mAh/g , test conditions: half-cell: 0.2C, 4--2.0V, greater than 154mAh; according to the actual battery 0.2C discharge, discharge voltage: 3.65V--2.5V, temperature 25 ℃, discharge capacity greater than 150mAh.

6、Cycle times 2000 times

The performance of lithium-ion battery mainly depends on the positive and negative materials, lithium ferrous phosphate as the cathode material of lithium-ion batteries is something that appeared only in recent years, and it is July 2005 that the domestic development of high-capacity lithium ferrous phosphate battery. Its safety performance and cycle life is not comparable to other materials, and these are the most important technical indicators of the power battery. 1CDOD charging and discharging cycle life up to 2000 times. Single battery overcharge voltage 30V does not burn, puncture does not explode.

Lithium ferrous phosphate cathode material can be made into larger capacity lithium-ion batteries, easier to use in series to meet the need for frequent charging and discharging of electric vehicles, its non-toxic, non-polluting, good safety performance, wide source of raw materials, cheap, long life and other advantages, is the new generation of lithium-ion batteries, the ideal cathode material.