Constant-temperature heating and liquid injection device and method of lithium ion battery

Abstract

The invention discloses a constant-temperature heating and liquid injection device of a lithium ion battery. The constant-temperature heating and liquid injection device comprises a first electrolyte heating tank, a second electrolyte heating tank, an electrolyte constant-temperature buffer tank, a liquid injection system and a lithium battery positioning fixture, wherein one end of the first electrolyte heating tank is connected with a first liquid inlet valve, the other end of the first electrolyte heating tank is connected with a liquid inlet in a side wall of the electrolyte constant-temperature buffer tank via a first electrolyte valve, and the bottom of the electrolyte constant-temperature buffer tank communicates with the liquid injection system via a third electrolyte valve. The invention also discloses a constant-temperature heating and liquid injection method of the lithium ion battery. With the adoption of the constant-temperature heating and liquid injection device for liquid injection of the lithium battery, the liquid injection accuracy and the stability of liquid injection quantity can be improved, the liquid injection quantity is free from the influence of an external environmental temperature, so that the liquid injection process capability is improved, and the production efficiency and the material utilization ratio are improved; and meanwhile, after an electrolyte is heated, the viscosity of the electrolyte can be reduced, the mobility and the infiltration performance of the electrolyte are improved, the liquid injection efficiency is improved, and the infiltration performance of the electrolyte is improved.

Description

technical field [0001] The invention relates to the technical field of lithium ion battery processing and manufacturing, in particular to a constant temperature heating liquid injection device for lithium ion batteries and a method thereof. Background technique [0002] In the prior art, the liquid injection process of flexible packaging lithium-ion power batteries is completed at room temperature, and its disadvantages are: at room temperature, the temperature changes greatly, the lowest temperature is 20°C, the highest temperature is 30°C, or even higher; In a large temperature range, the volume of the electrolyte will change with the temperature, that is, the density of the electrolyte will fluctuate greatly with the temperature; for the convenience of measurement, the liquid injection machine in the prior art adopts the method of volumetric measurement Instead of weighing, during the actual liquid injection process, the large fluctuations in the electrolyte density of th...

AI Technical Summary

Problems solved by technology

[0002] In the prior art, the liquid injection process of flexible packaging lithium-ion power batteries is completed at room temperature, and its disadvantages are: at room temperature, the temperature changes greatly, the lowest temperature is 20°C, the highest temperature is 30°C, or even higher; In a large temperature range, the volume of the electrolyte will change with the temperature, that is, the density of the electrolyte will fluctuate greatly with the temperature; for the convenience of measurement, the liquid injection machine in the prior art adopts the method of volumetric measurement Instead of weighing, during the actual liquid injection process, the large fluctuations in the electrolyte density of the lithium-ion battery due to temperature changes will cause huge fluctuations in the liquid injection volume of the lithium-ion battery. In this case, the yield rate of the liquid injection process will decrease. , but also reduces the production efficiency of lithium-ion batteries

[0003] Chinese Patent Publication No. CN101882674A, published on November 10, 2010, discloses a lithium-ion battery liquid injection device and its technology. The invention discloses a lithium-ion battery liquid injection device, which includes a vacuum cover, a base, The vacuum cover and the base are tightly arranged together by a seal lock. The vacuum cover is provided with a vacuum tube and a normal pressure tube. The vacuum tube is connected with a vacuum gauge. There is a second battery valve on the tube, a high-pressure tube is also set on the vacuum cover, a pressure gauge and a second solenoid valve are arranged on the high-pressure tube in turn, and the lithium-ion battery injection process is also disclosed. Put the battery in the vacuum cover, evacuate to 0.06 MPa, keep it for 10 seconds, return to normal atmospheric pressure, inject 0.4 MPa chlorine gas into the vacuum cover, and keep it for 1 minute, return to normal atmospheric pressure, and then evacuate to 0.02 Mpa Pa, after returning to normal pressure, take out the battery; it can be seen that the invention mainly improves the prior art from the aspects of the atmosphere and vacuum degree during liquid injection to speed up the battery’s absorption of electrolyte and improve the efficiency of liquid injection, but it does not control lithium. The amount of liquid injected in the ion battery may be due to temperature changes, changes in the density of the electrolyte, and a large difference in the quality of the electrolyte injected into the lithium-ion battery, which reduces the problem of yield

Images