Porous polyimide film, lithium ion secondary battery, and all-solid-state battery
There is provided a porous polyimide film in which the pore distribution width A represented by the following formula is 1.15 or less, the average pore diameter is within a range of 0.50 μm to 3.0 μm, and the air permeation speed is 30 seconds or less: A =( D 84 /D 16 ) 1/2 wherein D 16 is the pore diameter at 16% cumulation from the small diameter side of pores, and D 84 is the pore diameter at 84% cumulation from the small diameter side of pores.
1. A porous polyimide film comprising:
the porous polyimide film which has a pore distribution width A of 1.15 or less represented by the following formula, an average pore diameter within a range of 0.50 μm to 3.0 μm, an air permeation speed of 30 seconds or less, and a pore circularity is 0.85 or more,
A =( D 84 /D 16 ) 1/2 2
wherein D 16 is a pore diameter at 16% cumulation from a small diameter side of pores, and D 84 is the pore diameter at 84% cumulation from the small diameter side of pores.
2. The porous polyimide film according to claim 1 , wherein the pore distribution width is 1.13 or less.
3. The porous polyimide film according to claim 1 , wherein the pore distribution width is 1.12 or less.
4. The porous polyimide film according to claim 1 , wherein the average pore diameter is within a range of 0.8 μm to 2.5 μm.
5. The porous polyimide film according to claim 1 , wherein the average pore diameter is within a range of 0.8 μm to 2.4 μm.
6. The porous polyimide film according to claim 1 , wherein the air permeation speed is 20 seconds or less.
7. The porous polyimide film according to claim 1 , wherein the air permeation speed is 15 seconds or less.
8. The porous polyimide film according to claim 1 , wherein the pore circularity is 0.90 or more.
9. The porous polyimide film according to claim 1 , wherein an average thickness is within a range of 10 μm to 1000 μm.
10. The porous polyimide film according to claim 1 , wherein an average thickness is within a range of 20 μm to 500 μm.
11. The porous polyimide film according to claim 1 , wherein a void ratio of the film is within a range of 50% to 80%.
12. The porous polyimide film according to claim 1 , wherein a void ratio of the film is within a range of 55% to 75%.
13. A lithium ion secondary battery comprising the porous polyimide film according to claim 1 .
14. The lithium ion secondary battery according to claim 13 , wherein the porous polyimide film is a separator.
15. An all-solid-state battery comprising the porous polyimide film according to claim 1 .