[[TitleIndustry]]

Is the lithium iron phosphate battery safe?

Date:Sep 20, 2019

Now, people buying new energy vehicles objectively choose between the two technologies of lithium iron phosphate battery and NMC

lithium battery. The insiders tell us: the NMC system that emphasizes the endurance and light weight of the vehicle. Lithium iron phosphate is selected for safety. In this regard, consumers are eager to give the industry a practical answer from a technical point of view: Is lithium iron phosphate battery safe? This question should be answered in terms of material/structural stability, production process, and charge and discharge characteristics.


1. Lithium iron phosphate is currently the safest cathode material for lithium-ion batteries. It does not contain any heavy metal elements harmful to human body. It is difficult to precipitate oxygen in the olivine structure, which improves the stability of the material.


2. The production process of lithium iron phosphate battery is almost the same as that of other lithium battery types. The core processes are: batching, coating, rolling, sheeting and winding. In the compounding process, the lithium iron phosphate material has relatively poor conductivity. Therefore, the particles are generally made smaller. The objective effect of this is that the internal arrangement is more uniform, which promotes the formation of a balanced voltage platform and can be maintained while working. The battery is in a stable state.


3. Charge and discharge are two basic working conditions of lithium batteries. When the lithium iron phosphate battery is charged and discharged, since the iron ion oxidation ability is not strong, oxygen is not released, and it is naturally difficult to generate a redox reaction with the electrolyte, which makes the lithium iron phosphate battery charge and discharge process in a safe environment. Not only that, lithium iron phosphate batteries are difficult to undergo a vigorous redox reaction during large-rate discharge and even during overcharge and discharge. At the same time, after deintercalation of lithium, the lattice change causes the final volume of the unit cell (the smallest constituent unit of the crystal) to shrink, which just offsets the increased volume of the carbon negative electrode in the reaction. Therefore, in the charge and discharge, the lithium iron phosphate battery It can maintain the stability of the physical structure and eliminate the hidden danger of battery explosion caused by the increase in volume.

 

The safety of the battery mentioned above is for the sake of convenience. The monomer is taken as an example. When it is put into use, the lithium iron phosphate battery needs to provide the rated voltage and capacity suitable for the electric appliance. In this case, lithium iron phosphate is required. The battery is configured to work, that is, the lithium iron phosphate battery is equipped into a practical lithium battery pack by series/parallel/serial-parallel connection. The most important thing to pay attention to in this grouping work is the consistency of each individual battery. Usually, it also has a balanced management system that guarantees the safety of lithium battery use through key parameter control, which is a common feature of various lithium battery packs.


Previous: How to disassemble the motherboard battery

Next: 18650 lithium battery repair method