Ⅰ. What technology does lithium iron phosphate battery use?
The unique feature of the lithium iron phosphate battery is that it adopts an olive-shaped crystal structure. The crystal is the shape after crystallization, which is divided into ions/molecules/atoms/metal crystals.
That is, a crystal formed by the combination of positive and negative ion groups through ionic bonds in a certain proportion. Generally speaking, ionic crystals are brittle and hard, have high melting point and high boiling point, and can conduct electricity when melted or dissolved. The basis of all lithium-ion batteries, including lithium iron phosphate battery technology, is ionic conductivity.
Most of the internal crystal structures of the positive electrode of lithium ion battery UPS adopts a “spinel structure” arrangement, which is the case for lithium manganate, lithium cobaltate, and ternary lithium batteries.
This structure consists of 8 small cubic units composed of spinel unit cells (units that make up crystals, which can be literally understood as crystal cells), which are combined into an octahedral crystal structure. The olive-shaped crystals of lithium iron phosphate batteries are short cylinders.
The above three kinds of lithium batteries with spinel structure have their own characteristics. Lithium cobalt oxide batteries have excellent overall performance, but have low capacity and safety problems, and are more expensive for market promotion; lithium manganate batteries are easy to obtain due to materials, low cost, and good safety, but poor cycle performance and storage performance;
The ternary lithium battery is intended to reconcile the shortcomings of the two, the capacity has been increased, and the stability of the structure has also improved the safety, but the price is still relatively expensive, because the strategic raw material cobalt is required. The general disadvantage of spinel lithium-ion batteries is that the power is not large and is not suitable for large-scale.
Ⅱ. The technical characteristics and economy of lithium iron phosphate batteries are suitable for large and medium-sized market scenarios
1. Moderate voltage of lithium iron phosphate battery: nominal voltage 3.2V, termination voltage 3.6V, termination voltage 2.0V;
2. Large theoretical capacity and energy density of 170mAh/g;
3. Good thermal stability and high temperature resistance;
4. The battery has moderate energy storage, and the positive electrode material is compatible with most electrolyte systems;
5. The termination voltage is 2.0V, which can release more capacity, and the discharge capacity is large and balanced;
6. The voltage platform has good characteristics, and the balance of the charging and discharging voltage platform can be close to the regulated power supply.
The above technical features enable the realization of the ideal of high power and safety, which strongly promotes the large-scale application of lithium iron phosphate batteries.
In addition to technical features, lithium iron phosphate batteries have two market-oriented advantages: 1. Cheap raw materials and abundant resources; 2. No precious metals, non-toxic, and environmentally friendly products. This makes the application of lithium iron phosphate batteries shine in the current new energy vehicle market, and has become the preferred battery energy storage technology for base stations.