Low temperature have any influence on the performance of lithium iron phosphate batteries?

Source: 2020 - 03 - 28 most hits: low temperature of the lithium iron phosphate battery at present, the influence of lithium iron phosphate battery is the most widely used batteries in electric cars. They are safe, long life, but the lithium iron phosphate has a fatal flaw: its low temperature performance slightly less than other technology system. Low temperature of the positive and negative electrolyte of lithium iron phosphate and binder has certain influence. For example, the electrical conductivity of the lithium iron phosphate anode itself is very poor. Under the influence of low temperature, the speed of the graphite embedded lithium, short negative on the surface of the metal lithium, assuming fees after the lack of time to be put into use, lithium metal is not fully embedded graphite, metallic lithium continue to exist on the surface of the part of the negative, it may form lithium dendrite, affect the safety of the battery; When the low temperature, the electrolyte viscosity increase, lithium ion removal impedance increase. In addition, in the process of the production of the lithium iron phosphate, adhesive is a critical element and low temperature is will have a larger effect on the function of the adhesive. Low temperature impact on lithium titanate battery is also a lithium battery, lithium titanate battery low temperature resistance is better. Spinel lithium titanate battery anode materials structure embedded in the lithium electric potential is about 1. 5 v, does not constitute a lithium dendrite, the process of charging and discharging volume strain is less than 1%. Nano titanium acid lithium batteries can be large current charge and discharge, low temperature quick charge, to ensure the durability and safety of the battery. Give priority to with lithium titanate battery silver dragon new energy, its products have the normal charge and discharge ability, in - 50 - 60℃。 Lithium titanate battery it has advantage of low temperature quick charge material, this is the envy of other cells. Why charge need more than the discharge temperature? Many enterprises of battery products can be normal discharge under low temperature, but at the same temperature, it is difficult to normal charge, can't even charge. When Li + embedded in graphite material, the first thing to do is dissolved, the process will consume a certain amount of energy and prevent the scattered Li + to graphite. Li + from graphite material, by contrast, in the process of solution has a solvation, solvation process does not consume energy, so Li + can quickly out of graphite. Therefore, significantly lower than the discharge charge acceptability of graphite materials acceptability. Under low temperature, there is a risk of the battery. Because with the loss of the temperature, the dynamic characteristics of graphite anode has changed. In the process of charging, the cathode electrochemical polarization is obvious enhancement. Isolated from the short metal lithium, lithium dendrite formation, break through the diaphragm lead to the positive and negative short circuit. To avoid the low temperature lithium ion batteries. When the battery must be under the low temperature, it is necessary to choose a small current ( The slow charge) Rechargeable lithium ion batteries, and the location of the lithium ion battery charge, and then ensure that lithium metal anode reaction separation graphite, graphite anode embedded in the beginning. Industrial enterprises and research institutions for resistance to low temperature of the battery is studied and the function, mostly in the existing on the improvement of the positive and negative material technology, and through the battery part of positive environmental temperature for the work of the battery under low temperature conditions. With the further development of the technology, lithium batteries will have a further breakthrough in low temperature environment.