Test method for diaphragm technology of lithium battery -Lithium - Ion Battery Equipment
What is the test method of lithium diaphragm technology?
1. Thickness
There are two important online control technologies for the diaphragm thickness of lithium ion battery, one is MD (vertical) control and the other is CD (horizontal) control; The other is diaphragm online machine vision testing technology. The so-called MD control and CD control refer to the thickness closed-loop control in the MD direction by controlling the feeding screw speed or traction speed; As well as the data measurement through the scanning frame, the data closed-loop control in the CD direction is finally realized.
2. Curvature
Some companies also call it camber degree, which refers to the arc generated after the lithium-ion battery diaphragm is cut. When the arc is clear, it will cause uneven laminations. When it is wound, it will generate vortices, which will cause exposed electrode plates and short circuit. The detection method is to lay the diaphragm strip on the desktop and compare the parallelism with the edge of the steel ruler to obtain the radian of the diaphragm.
3. Air permeability
The time required for a certain volume of air to pass through the membrane under certain conditions, also known as Gurley value, has a certain impact on the performance of lithium ion batteries. Generally, ASTM detection method is used.
4. Porosity
The proportion of the void volume to the whole volume is detected by liquid absorption calculation method and detection method. The liquid absorption calculation method is to soak the lithium diaphragm in a known solvent, and calculate the void volume occupied by the liquid by measuring the mass difference before and after the diaphragm is soaked. The mercury intrusion detection method is to apply pressure to the diaphragm by using external force to press mercury into the pores of the diaphragm, and then calculate the porosity of the diaphragm by measuring the volume of mercury pressed, Take the uniform value after multiple measurements.(Lithium - Ion Battery Equipment)
1. Thickness
There are two important online control technologies for the diaphragm thickness of lithium ion battery, one is MD (vertical) control and the other is CD (horizontal) control; The other is diaphragm online machine vision testing technology. The so-called MD control and CD control refer to the thickness closed-loop control in the MD direction by controlling the feeding screw speed or traction speed; As well as the data measurement through the scanning frame, the data closed-loop control in the CD direction is finally realized.
2. Curvature
Some companies also call it camber degree, which refers to the arc generated after the lithium-ion battery diaphragm is cut. When the arc is clear, it will cause uneven laminations. When it is wound, it will generate vortices, which will cause exposed electrode plates and short circuit. The detection method is to lay the diaphragm strip on the desktop and compare the parallelism with the edge of the steel ruler to obtain the radian of the diaphragm.
3. Air permeability
The time required for a certain volume of air to pass through the membrane under certain conditions, also known as Gurley value, has a certain impact on the performance of lithium ion batteries. Generally, ASTM detection method is used.
4. Porosity
The proportion of the void volume to the whole volume is detected by liquid absorption calculation method and detection method. The liquid absorption calculation method is to soak the lithium diaphragm in a known solvent, and calculate the void volume occupied by the liquid by measuring the mass difference before and after the diaphragm is soaked. The mercury intrusion detection method is to apply pressure to the diaphragm by using external force to press mercury into the pores of the diaphragm, and then calculate the porosity of the diaphragm by measuring the volume of mercury pressed, Take the uniform value after multiple measurements.(Lithium - Ion Battery Equipment)
