Comparison of advantages and disadvantages between iron-lithium battery and lithium polymer battery

Introduction of iron lithium battery

The iron-lithium battery is a kind of battery in the lithium battery family, and the positive electrode material is mainly lithium iron phosphate material, which is also referred to as lithium- iron-battery. Compared with traditional lead-acid batteries, lithium-ion batteries have significant advantages in terms of operating voltage, energy density and cycle life.

Advantages of electric vehicle iron lithium battery

(1) High energy density: the nominal voltage is 3.2V, the energy density is about 4 times that of lead-acid batteries, and the volume is small and the weight is light;

(2) Strong safety: Lithium iron phosphate cathode material has good electrochemical performance, the charging and discharging platform is very stable, the structure is stable during charging and discharging, the battery does not burn, does not explode, and has good safety;

(3) Good high temperature performance: the battery works normally when the external temperature is 55 °C;

(4) High power output: standard discharge is 0.2C and 3C can be charged and discharged;

(5) Long cycle life: 1C charge and discharge at room temperature, the capacity of the monomer after 2000 cycles is still greater than 80%;

(6) Environmental protection: The whole production process is clean and non-toxic, and all raw materials are non-toxic.

Electric vehicle iron lithium battery

There is a danger of explosion. When the lithium battery is charged and discharged at a high current, the inside of the battery continues to heat up. The gas generated during the activation process expands, the internal pressure of the battery increases, and the pressure reaches a certain level. If the outer casing is scratched, it will rupture, causing Leakage, fire, or even explosion.

The advantages of lithium iron phosphate batteries are:

The lithium iron phosphate battery has a long life and a cycle life of more than 2,000 times. Under the same conditions, lithium iron phosphate batteries can be used for 7 to 8 years.

It’s safe to use. Lithium iron phosphate batteries undergo rigorous safety testing and will not explode even in traffic accidents.

Charging is fast. With a dedicated charger, the battery can be fully charged by charging at 1.5C for 40 minutes.

The lithium iron phosphate battery is resistant to high temperatures, and the lithium iron phosphate battery can reach a hot air value of 350 to 500 degrees Celsius.

The lithium iron phosphate battery has a large capacity.

Lithium iron phosphate batteries have no memory effect.

The lithium iron phosphate battery is environmentally friendly, non-toxic, non-polluting, with a wide range of raw materials and low prices.

The disadvantages of lithium iron phosphate batteries are:

The lithium iron phosphate battery has a low tap density and a density of generally 0.8 to 1.3.

The conductivity is poor, the lithium ion diffusion rate is slow, and the actual specific capacity is low when the charge and discharge are high.

The lithium iron phosphate battery has poor low temperature performance.

lithium iron phosphate battery has a long life of about 2,000 times, but the life of lithium iron phosphate battery pack is short, generally about 500 times.

Advantages and disadvantages of several cathode materials for lithium batteries

The performance of a lithium-ion battery depends primarily on the structure and properties of the materials used in the battery used. These battery internal materials include a negative electrode material, an electrolyte, a separator, a positive electrode material, and the like. The choice and quality of the positive and negative materials directly determine the performance and price of the lithium ion battery. Therefore, the research of low-cost, high-performance positive and negative materials has always been the focus of the development of the lithium-ion battery industry. The anode material is generally made of carbon material, and the current development is relatively mature. The development of cathode materials has become an important factor restricting the further improvement of lithium ion battery performance and further price reduction. In the current commercial production of lithium-ion batteries, the cost of the cathode material accounts for about 40% of the total battery cost, and the decrease in the price of the cathode material directly determines the price of the lithium-ion battery. This is especially true for lithium-ion power batteries. For example, a small lithium-ion battery for a mobile phone requires only about 5 grams of positive electrode material, and a lithium-ion battery that drives a bus may require up to 500 kilograms of positive electrode material.

To measure the quality of the positive electrode material of lithium ion battery, it can be evaluated from the following aspects: (1) The positive electrode material should have a higher oxidation-reduction potential, so that the battery has a higher output voltage; (2) lithium ion can A large amount of reversible intercalation and deintercalation in the positive electrode material to make the battery have a high capacity; (3) in the process of lithium ion insertion/deintercalation, the structure of the positive electrode material should be changed as little as possible or small, Ensure good cycle performance of the battery; (4) The oxidation-reduction potential of the positive electrode should be changed as little as possible during the insertion/deintercalation process of lithium ions, so that the voltage of the battery does not change significantly to ensure the battery is charged and discharged smoothly; (5) The positive electrode material should have a high electrical conductivity, which can make the battery charge and discharge at a large current; (6) the positive electrode does not chemically react with the electrolyte; (7) the lithium ion should have a large diffusion in the electrode material. The coefficient is convenient for the battery to be quickly charged and discharged; (8) the price is cheap and the environment is not polluted.

Lithium ion battery cathode materials are generally lithium oxides. LiCoO2, LiNiO2, LiMn2O4, LiFePO4 and vanadium oxides have been studied. Conductive polymer cathode materials have also attracted great interest.

The page contains the contents of the machine translation.