Papers useful as thermal insulation and flame barriers for battery cells
A paper suitable for use as a cell-to-cell flame barrier in a battery, and a battery comprising the paper, the paper comprising 40 to 70 weight percent fibrids and 30 to 60 weight percent mica, based on the total weight of the fibrids and mica in the paper; wherein the fibrids comprise a blend of 80 to 20 weight percent polymer and 20 to 80 weight percent aerogel powder, based on the total weight of the polymer and aerogel powder in the fibrids; the paper having a thickness of 100 to 4000 micrometers.
1. A paper suitable for use as a cell-to-cell flame barrier in a battery, the paper comprising:
40 to 70 weight percent fibrids, and
30 to 60 weight percent mica,
based on the total weight of the fibrids and mica in the paper; wherein the fibrids comprise a blend of
80 to 20 weight percent polymer, and
20 to 80 weight percent aerogel powder,
based on the total weight of the polymer and aerogel powder in the fibrids;
the paper having a thickness of 100 to 4000 micrometers.
2. The paper of claim 1 wherein the fibrids comprise a blend of
60 to 40 weight percent polymer, and
40 to 60 weight percent aerogel powder.
3. The paper of claim 1 wherein the paper comprises
50 to 60 weight percent fibrids, and
40 to 50 weight percent mica.
4. The paper of claim 1 further comprising floc, in an amount as much as 20 weight percent, based on the total weight of the fibrids, mica, and floc in the paper.
5. The paper of claim 4 , wherein the floc is an aramid floc.
6. The paper of claim 5 , wherein the aramid floc is poly(metaphenylene isophthalamide) floc.
7. The paper of claim 1 , wherein the polymer is an aramid.
8. The paper of claim 7 , wherein the aramid is poly(metaphenylene isophthalamide).
9. The paper of claim 1 having a thickness of 300 to 3000 micrometers.
10. The paper of claim 1 having a tensile strength of 0.5 to 100 MPa.
11. The paper of claim 1 having a thermal conductivity of 0.015 to 0.05 W/mK.
12. A battery comprising the paper of claim 1 .