From：CTECHI GROUP Limited Release time：2019-11-13
Overview：The use of lithium batteries in low-temperature areas in the north, the original full of lithium batteries, the capacity must be a discount, which brings new troubles to new energy vehicles and digital products users.
How does a lithium battery perform in a low temperature environment?
The use of lithium batteries in low-temperature areas in the north, the original full of lithium batteries, the capacity must be a discount, which brings new troubles to new energy vehicles and digital products users.
The battery has some similarities with people. After the climate turns cold, it is not so active. Lead batteries, lithium batteries and fuel cells are all affected by low temperature, but the degree is different.
Take the lithium iron phosphate battery, which is the most used on electric buses, as an example. The battery has high safety and long life, but the low temperature performance is slightly worse than that of other technical systems. The low temperature affects both the positive and negative electrodes of lithium iron phosphate, the electrolyte and the binder. For example, the lithium iron phosphate positive electrode itself has relatively poor electronic conductivity, and is prone to polarization in a low temperature environment, thereby reducing battery capacity; due to low temperature, the graphite lithium insertion rate is lowered, and it is easy to precipitate metallic lithium on the surface of the negative electrode, and if the charging time is insufficient When it is put into use, the metal lithium cannot be completely embedded in the graphite, and some metal lithium continues to exist on the surface of the negative electrode, which is likely to form lithium dendrites, which affects the safety of the battery. At low temperatures, the viscosity of the electrolyte increases, and the lithium ion migration resistance also follows. In addition, in the production process of lithium iron phosphate, the adhesive is also a very critical factor, and the low temperature also has a great influence on the performance of the adhesive.
Although lithium-ion batteries with graphite as the negative electrode can be discharged at -40 ° C, it is difficult to achieve conventional current charging at -20 ° C and lower, which is an area that the industry is actively exploring.