Lithium iron phosphate (LiFePO4) batteries are safer than ordinary lithium-ion batteries. They have a series of large cell sizes that can provide 5-100AH capacity and have much longer cycle life than traditional batteries. Among them, cylindrical lithium iron phosphate batteries are one of the most popular products in all series. They have many excellent functions:

High energy density, 270-340Wh/L; this means long working hours.

Stable discharge voltage.

Good consistency between different cores in the same batch.

Long cycle life, with 80% capacity remaining after 2,000 charge and discharge cycles.

Fast charging can be completed within 1 hour.

Safety and high temperature resistance.

Lithium iron phosphate is a lithium-ion battery, because energy is stored in the same way, it moves and stores lithium ions rather than lithium metals. These cells and batteries not only have high capacity, but also provide high power. At present, high-power lithium iron phosphate batteries have become a reality, they can be used as energy storage units or power supply.

In addition, lithium iron phosphate battery is one of the most vigorous batteries in history. Laboratory test data show that it has a maximum of 2,000 charge/discharge cycles, which is due to the extremely strong crystal structure of ferric phosphate, which will not be decomposed due to the repeated intercalation and de-intercalation of lithium ions during charging and discharging.

Although lithium ion (polymer) batteries with lithium cobalt oxide (LiCoO 2) provide the best mass energy density and bulk energy density, lithium cobalt oxide is very expensive and unsafe for large capacity lithium ion batteries. Recently, lithium iron phosphate has become the "best choice" for commercial lithium ion (and polymer) battery materials for large capacity and high power applications, such as notebook computers, power tools, electric wheelchairs, electric bicycles, electric cars and electric buses.

Lithium iron phosphate batteries have hybrid properties: they are as safe as lead-acid batteries (LA Battery) and as powerful as lithium-ion batteries.  The advantages of large size lithium ion (and polymer) batteries containing lithium iron phosphate are listed below.
Conventional Charging
In the traditional lithium-ion charging process, conventional lithium-ion batteries containing lithium iron phosphate need two steps to be fully charged.

Step 1: Use constant current (CC) charging to achieve about 60-70% of the charging state (SOC); when the charging voltage of each core reaches 3.65V (which is the upper limit of the effective charging voltage), step 2, constant voltage (CV) charging. Conversion from CC to CV means that the charging current is limited by the acceptable current of the battery under this voltage. Therefore, the charging current decreases gradually, just like charging capacitors through resistance, the voltage gradually reaches the final value.

In terms of time, step 1 (60-70% SOC) takes about one to two hours, and step 2 (30-40% SOC) takes about two hours.

Since overvoltage can be applied to lithium iron phosphate batteries without decomposition of electrolytes, 95% SOC can be charged only through step 1 of CC, or 100% SOC can be charged by CC+CV. This is similar to the safe mandatory charging of lead-acid batteries. The shortest total charging time is about two hours.
Large Overcharge Tolerance and Safer Performance
Lithium cobalt oxide batteries have very narrow overcharge tolerance, which is about 0.1V above the 4.2V charging voltage of each cell, which is also the upper limit of charging voltage. Continuous charging over 4.3V either impairs battery performance (e.g. shortens cycle life), or leads to fire or explosion.

Lithium iron phosphate batteries have a much wider overcharge tolerance of about 0.7V than the charging voltage of 3.5V per cell. Each cell of a lithium iron phosphate battery can be safely overcharged to 4.2V, but higher voltages will begin to decompose the organic electrolyte. However, lead-acid battery chargers are usually used to charge 12 V 4 batteries in series. The maximum voltage of these chargers is 14.4 V, whether they are AC power supply or AC generators used in automobiles. It works normally, but the lead-acid charger reduces the floating charge voltage to 13.8V, so it usually stops charging before the lithium iron phosphate battery pack reaches 100% full capacity. Therefore, a special lithium iron phosphate charger is needed to reliably reach 100% capacity.

These batteries are preferred for high-capacity and high-power applications due to increased safety factors. From the point of view of large overcharge tolerance and safety performance, lithium iron phosphate batteries are similar to lead-acid batteries.
Energy density is three times higher than that of lead-acid batteries.
Lead-acid batteries are water-containing systems. When discharging, the rated single core voltage is 2V. Lead is a heavy metal and its specific capacity is only 44Ah/kg. In contrast, lithium iron phosphate batteries are non-aqueous systems with a rated voltage of 3.2V at discharge. Its specific capacity exceeds 145 Ah/kg. Therefore, the weight energy density of lithium iron phosphate battery is 130Wh/kg, which is four times that of lead-acid battery (35Wh/kg). Three times higher energy density makes lithium iron phosphate battery more popular than lead-acid battery in technical use.
Lower cost
Lithium iron phosphate batteries have large overcharge tolerance and self-balancing characteristics, which can simplify the design of battery protection and equalization circuit board and reduce the cost. The one-step charging process allows the use of simpler traditional chargers to charge lithium iron phosphate batteries, rather than requiring expensive professional lithium-ion battery chargers.

Longer cycle life
Compared with lithium cobalt oxide batteries with 400 cycles, the cycle life of lithium iron phosphate batteries is extended to 2,000 cycles.

High temperature performance
Lithium cobalt oxide batteries are dangerous to operate at high temperatures (e.g. 60 C). However, lithium iron phosphate batteries can work better at high temperatures due to higher lithium ion conductivity.