Penetration strength

Mix Penetration Strength. The susceptibility of separators to particle penetration is characterized by mix penetration strength. During the winding of the spiral wrap construction considerable mechanical pressure is applied to the cathode-separator—anode interface. Any loose particle could be forced through the separator and short the cell. The mix penetration strength should be at least 100 kgf/mil for separators used in lithium-ion cells. 

Mix Penetration Strength. The force required to create a short through a separator due to mix (electrode material) penetration defines mix penetration strength. In this test force (with a /z in. diameter ball) is applied on the positive electrode/ separator/negative electrode sandwich, and the force at which the mix penetrates through the separator and creates an electronic short is called mix penetration force. Mix penetration strength is used to indicate the tendency of separators to allow short-... 

The responses taken into account in our study are cohesion and viscosity of the etntilsion. These responses are obtained by rheological and texture analysis. The cohesion (nondimensionat) represenUv the ratio between the penetration strength and the adhesion strength. 

The protection against a Phantom F-4 hitting at a velocity of 215 m s requires a minimum reinforced concrete thickness of 1.8 m and, at 150 m s, a minimum thickness of 1.2 m is needed. These thicknesses also take into account the penetration strength. 

Figure 20.7 shows the SEM of the Separion separator, where the ceramic materials coated over the surface of the nonwoven bonded polymer can be clearly observed. Separion separators are weak in puncmre strength and tensile stress and lower dielectric breakdown, but reasonably high in mix-penetration strength. The separator also is weak in coating adhesion. 

The mix penetration strength is a better measure for the strength of separator in batteries. In case of mix penetration test, electrode mix is pushed through the separator till it creates a short. This test simulates the real situation inside the battery more closely. 

The force required to CTeate a short through a separator due to mix (electrode material) penetration defines mix penetration strength. In this test force (with a half inch diameter ball) is applied on the positive electrode/separator/negative electrode... 

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