Advantages and disadvantages of lithium iron phosphate battery

Advantages and disadvantages of lithium iron phosphate battery.

Advantages:

1. Improvement of safety performance: the Pmuro bond in lithium iron phosphate crystal is stable and difficult to decompose, even at high temperature or overcharge, it will not collapse, heat or form a strong oxidizing substance like lithium cobalt oxide, so it has good safety.

2. Improvement of life: lithium iron phosphate battery refers to lithium ion battery which uses lithium iron phosphate as cathode material. The cycle life of long-life lead-acid battery is about 300times, with a maximum of 500times, while the cycle life of lithium iron phosphate power battery is more than 2000 times, and the standard charge (5 hour rate) can reach 2000 times.

3. Good high temperature performance: the electrothermal peak value of lithium iron phosphate is 350 ℃-500 ℃, while that of lithium manganate and lithium cobalt is only about 200 ℃. The operating temperature range is wide (- 20C--75C), and the electrothermal peak value of lithium iron phosphate is 350C-500C, while that of lithium manganate and lithium cobalt is only about 200C.

4. Large capacity: no matter what state the battery is in, it can be used whenever it is charged, and there is no need to discharge it first and then recharge it.

5. Light weight: the volume of lithium iron phosphate battery with the same capacity is 2x3 of the volume of lead-acid battery, and its weight is 1x3 of lead-acid battery.

6. Environmental protection: lithium iron phosphate batteries are generally considered to be free of heavy metals and rare metals (Ni-MH batteries need rare metals), non-toxic (SGS certified), pollution-free, in line with European RoHS regulations, and are absolutely green battery certificates.

Disadvantages:

The main results are as follows:

1. The vibrating density of the positive electrode of lithium iron phosphate battery is small, and the density is generally about 0.8 to 1.3. It's big.

2. In the sintering process of preparation of lithium iron phosphate, it is possible for iron oxide to be reduced to elemental iron in high temperature reducing atmosphere. Elemental iron can cause a slight short circuit in the battery.

3. The low temperature performance of lithium iron phosphate battery is poor: lithium iron phosphate has some performance defects, such as low vibration density and compaction density, resulting in low energy density of lithium ion battery. The low temperature performance is poor, and even its nanocrystallization and carbon coating do not solve this problem.

4. The preparation cost of the material and the manufacturing cost of the battery are high, the yield of the battery is low, and the consistency is poor.

5. The single battery life of lithium iron phosphate battery is long, about 2000 times, but the life of lithium iron phosphate battery pack is short, generally about 500 times.

Principle and structure of lithium iron phosphate battery:

1. At present, commercial lithium iron phosphate batteries are generally composed of the following parts: positive electrode material (lithium iron phosphate), negative electrode material (graphite), aluminum foil (positive) and copper foil (negative) as positive and negative current collector. positive and negative electrode ears (that is, drawn from the current collector).

2. There are diaphragm, electrolyte, aluminum-plastic film and battery protection board. The use of winding type, made of 18650 battery.

3. The principle is that when discharging, Li ions migrate from the negative to the positive, while when charging, the Li ions migrate from the positive to the negative, which is a rocking-chair battery.