Back to results
US 2024/0322372 A1Published application
Separator and preparation method thereof, electrochemical device, electrochemical apparatus and powered device
AssigneesContemporary Amperex Technology Co., Limited, Sinoma Lithium Battery Separator (Changde) Co., Ltd.
InventorsJianrui Yang, Fenggang Zhao, Lianguang Wang, Tianle Yang
Life of this patent
Estimating the term…
Abstract
The present application provides a separator and a preparation method thereof, an electrochemical device, an electrochemical apparatus and a powered device. The separator comprises a base film, the base film has a tensile energy per unit thickness of ≥1.8 J/10 μm in both MD direction and TD direction, and an elongation of ≥150% in both MD direction and TD direction, and the thickness of the base film is 2 μm˜40 μm.
Claims19
A separator, comprising a base film,
- the base film has a tensile energy per unit thickness of ≥1.8 J/10 μm in both longitudinal MD direction and transverse TD direction, and an elongation of ≥150% in both MD direction and TD direction;
- wherein, the tensile energy per unit thickness is
- F
- ×
- Δ
-
- L
- d
- ×
- 1
-
- 0
- ,
- F represents a force value in N at which a test sample of the base film with a gauge length of 40 mm and a width of 15 mm is stretched to break at a constant rate of 50 mm/min, ΔL represents a tensile displacement in m at which the test sample is stretched to break, and d represents an initial thickness in μm of the test sample;
- and
- the thickness of the base film is 2 μm˜40 μm.
13 more elements
A method for preparing a separator, comprising:
- (a) providing a molten base film formulation comprising a polymer and a pore-forming agent;
- (b) extruding the base film formulation and cooling to form a sheet;
- (c) stretching the sheet in MD direction;
- (d) stretching the sheet in TD direction;
- (e) removing the pore-forming agent from the sheet to form a porous sheet;
- (f) heat-setting the porous sheet to obtain a base film;
- wherein, the base film is used as the separator, or the base film is used as the separator after post-treatment;
- the base film has a tensile energy per unit thickness of ≥1.8 J/10 μm in both longitudinal MD direction and transverse TD direction, and an elongation of ≥150% in both MD direction and TD direction;
- wherein, the tensile energy per unit thickness is
- F
- ×
- Δ
-
- L
- d
- ×
- 1
-
- 0
- ,
- F represents a force value in N at which a test sample of the base film with a gauge length of 40 mm and a width of 15 mm is stretched to break at a constant rate of 50 mm/min, ΔL represents a tensile displacement in m at which the test sample is stretched to break, and d represents an initial thickness in μm of the test sample;
- and
- the thickness of the base film is 2 μm˜40 μm.
20 more elements
Dependencies are inferred from the claim text.