Reinforced ventilation holes

Abstract

Provided herein is a vent for use in a sealed container, the vent comprising at least one protective fluoropolymer layer and at least one reinforcing layer, the at least one protective fluoropolymer layer partially permeating the at least one reinforcing layer, the at least one protective fluoropolymer layer having a pore size of at least 600 cm@3 at 30° C., as measured using a method described herein. 3 / g carbon dioxide (CO2) to water (HO) selectivity, and at least 1,000 cm at 30°C 3 / (m 2 It has a CO2 permeability of 1000kJ / 24h (×24h×atm).

Description

[Technical Field]

[0001] Field FIELD OF THE DISCLOSURE The present disclosure relates to vents for enclosures and enclosures including vents, and more particularly to vents for flexible enclosures and flexible enclosures including vents. [Background technology]

[0002] background Vents and vent assemblies can be used to reduce pressure fluctuations and control humidity within an enclosure. Such vent and vent devices must also prevent the ingress of dirt or other contaminants and must also prevent the ingress of water.

[0003] In sealed containers used to hold liquids, it is necessary to ensure that a vent or vent assembly prevents leakage of the liquid held therein, while at the same time preventing gas generated within the sealed container from escaping through the vent and building up pressure within the sealed container.

[0004] An example of a sealed container used to hold a liquid is a battery pouch that holds a battery electrolyte. A typical battery pouch is made of a flexible material and includes one or more vent holes in the battery pouch wall. This allows gas generated by the battery electrolyte during use to escape from the battery pouch, preventing the pressure within the battery pouch from rising above a predetermined threshold, preventing the battery pouch from bursting or otherwise leaking, or preventing the battery pouch from losing capacity due to increased pressure.

[0005] Such vents must be selective in the gases they allow to pass through, typically by substantially preventing water vapor from entering the enclosure while allowing gases such as carbon dioxide generated during the life of the enclosure to exit the enclosure through the vent.

[0006] However, selectivity must sometimes be sacrificed in order for the vent to be strong enough for long life in a given application.

[0007] Therefore, there remains a need for an improved vent or vent assembly for use in a closed container. Summary of the Invention

[0008] Accordingly, at least some embodiments are directed to providing an improved vent assembly that solves at least one of these problems.

[0009] Abstract According to a first aspect, there is provided a vent for use in a sealed container, the vent comprising at least one protective fluoropolymer layer and at least one reinforcing layer, the at least one protective fluoropolymer layer at least partially permeating the at least one reinforcing layer, the at least one protective fluoropolymer layer having a permeability of at least 600 cm@3 at 30°C, as measured using a method described herein. 3 / g carbon dioxide (CO2) to water (HO) selectivity, and at least 1,000 cm at 30°C 3 / (m 2 It has a CO2 permeability of 1000kJ / 24h (×24h×atm).

[0010] It has been found that providing a vent that includes at least one protective fluoropolymer layer that at least partially penetrates at least one reinforcing layer significantly increases the strength of the vent while substantially preserving the selectivity of the at least one protective fluoropolymer layer, resulting in a vent that significantly increases the pressure resistance of the vent.

[0011] The CO2 permeability of materials used in vents typically decreases as the thickness of the material increases. The CO2 permeability of materials used in vents typically increases as the temperature of the material increases. Typically, the layer thickness of the vent must compromise the requirements of permeability and selectivity with the requirements of structural strength so that the vent can withstand the pressures that may occur during use. However, it has been found that vents according to the present embodiment maintain good CO2 permeability through at least one protective fluoropolymer layer while also achieving structural strength that enhances resistance to burst pressures.

[0012] In some embodiments, at least the protective fluoropolymer layer may include a fluoropolymer with a melting point below 320°C.

[0013] The at least one protective fluoropolymer layer can comprise a fluoropolymer selected from the group consisting of perfluoroalkoxyalkane (PFA), fluorinated ethylene propylene (FEP), polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), or polyethylenetetrafluoroethylene (ETFE). The at least one protective fluoropolymer layer can comprise PFA or FEP. For example, the at least one protective fluoropolymer layer can comprise PFA.

[0014] In some embodiments, the at least one protective fluoropolymer layer can have a thickness of about 5 μm to about 150 μm. The at least one protective fluoropolymer layer can have a thickness of about 5 μm to about 125 μm. The at least one protective fluoropolymer layer can have a thickness of about 5 μm to about 100 μm. The at least one protective fluoropolymer layer can have a thickness of about 5 μm to about 75 μm. The at least one protective fluoropolymer layer can have a thickness of about 5 μm to about 50 μm. The at least one protective fluoropolymer layer can have a thickness of about 5 μm to about 25 μm. The at least one protective fluoropolymer layer can have a thickness of about 10 μm to about 150 μm. The at least one protective fluoropolymer layer can have a thickness of about 20 μm to about 150 μm. The at least one protective fluoropolymer layer can have a thickness of about 30 μm to about 150 μm. The at least one protective fluoropolymer layer can be from about 40 μm to about 150 μm thick.The at least one protective fluoropolymer layer can be from about 50 μm to about 150 μm thick.

[0015] In some embodiments, the at least one protective fluoropolymer layer can be 10 μm to 50 μm thick. In some embodiments, the at least one protective fluoropolymer layer can be 10 μm to 25 μm thick. In some embodiments, the at least one protective fluoropolymer layer can be 12 μm to 25 μm thick. For example, the at least one protective fluoropolymer can be 10 μm, 12 μm, 15 μm, 20 μm, 25 μm, 30 μm, 40 μm, or 50 μm thick.

[0016] At least one reinforcing layer can be a mesh.

[0017] The at least one reinforcing layer may have a generally open structure. The at least one reinforcing layer may be porous. The at least one reinforcing layer may be more porous than the at least one protective fluoropolymer layer. The at least one reinforcing layer may have a higher gas permeability than the at least one protective fluoropolymer layer. Therefore, the permeability of the vent hole may be primarily determined by the permeability of the at least one protective fluoropolymer layer.

[0018] At least one reinforcing layer can be an expanded polymer layer. At least one reinforcing layer can have a fibrillated structure. At least one reinforcing layer can have a node-and-fibril structure in which the nodes and fibrils are interconnected. Thus, at least one protective fluoropolymer layer can at least partially penetrate the pores and voids between the nodes and fibrils.

[0019] At least one reinforcing layer may comprise ePTFE.

[0020] The at least one reinforcing layer may have a thickness of about 1 μm to about 100 μm. The at least one reinforcing layer may have a thickness of about 5 μm to about 100 μm. The at least one reinforcing layer may have a thickness of about 8 μm to about 100 μm. The at least one reinforcing layer may have a thickness of about 10 μm to about 100 μm. The at least one reinforcing layer may have a thickness of about 15 μm to about 100 μm. The at least one reinforcing layer may have a thickness of about 20 μm to about 100 μm. The at least one reinforcing layer may have a thickness of about 30 μm to about 100 μm. The at least one reinforcing layer may have a thickness of about 1 μm to about 80 μm. The at least one reinforcing layer may have a thickness of about 1 μm to about 60 μm. The at least one reinforcing layer may have a thickness of about 1 μm to about 40 μm. The at least one reinforcing layer may have a thickness of about 1 μm to about 30 μm. The at least one reinforcing layer may have a thickness of about 1 μm to about 25 μm.

[0021] The vent may include at least two reinforcing layers with a protective fluoropolymer layer sandwiched between the at least two reinforcing layers.

[0022] The ventilation holes must be at least 600 cm at 30°C. 3 / g of carbon dioxide to water vapor selectivity. The vent may have a selectivity of at least 700 cm at 30°C. 3 / g of carbon dioxide to water vapor selectivity. The vent may have a selectivity of at least 800 cm at 30°C. 3 / g of carbon dioxide to water vapor selectivity. The vent may have a selectivity of at least 900 cm at 30°C. 3 / g of carbon dioxide to water vapor selectivity. The vent may have a selectivity of at least 1000 cm at 30°C. 3 / g of carbon dioxide to water vapor selectivity.

[0023] The ventilation hole is approximately 600 cm at 30°C. 3 / g ~ approx. 2000cm 3 / g of carbon dioxide to water vapor selectivity. The vent is approximately 700 cm at 30°C. 3 / g ~ approx. 2000cm 3 / g of carbon dioxide to water vapor selectivity. The vent is approximately 800 cm at 30°C. 3 / g ~ approx. 2000cm 3 / g of carbon dioxide to water vapor selectivity. The vent is approximately 900 cm at 30°C. 3 / g ~ approx. 2000cm 3 / g of carbon dioxide to water vapor selectivity. The vent has a selectivity of about 1000 cm at 30°C. 3 / g ~ approx. 2000cm 3 / g of carbon dioxide to water vapor selectivity.

[0024] The ventilation must be at least 4,000 cm at 30°C. 3 / (m 2 The vent may have a carbon dioxide (CO2) permeability of at least 10,000 cm@2 at 30°C. 3 / (m 2The vent may have a carbon dioxide (CO2) permeability of at least 25,000 cm@2 at 30°C. 3 / (m 2 The vent may have a carbon dioxide (CO2) permeability of at least 50,000 cm@2 at 30°C. 3 / (m 2 The vent may have a carbon dioxide (CO2) permeability of at least 75,000 cm@2 at 30°C. 3 / (m 2 The vent may have a carbon dioxide (CO2) permeability of at least 100,000 cm3 at 30°C. 3 / (m 2 It can have a carbon dioxide (CO2) permeability of 1000 kJ / cm² / hour (24h x 24h x atm).

[0025] The ventilation hole is approximately 1,000 cm at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm 3 / (m 2 The ventilation holes have a carbon dioxide (CO2) permeability of approximately 4,000 cm at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 25,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 50,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 75,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm 3 / (m 2 The ventilation holes have a carbon dioxide (CO2) permeability of approximately 1,000 cm at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 190,000cm 3 / (m 2 The ventilation holes have a carbon dioxide (CO2) permeability of approximately 1,000 cm at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 180,000cm 3 / (m 2 The ventilation holes have a carbon dioxide (CO2) permeability of approximately 1,000 cm at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 170,000cm 3 / (m 2 The ventilation holes have a carbon dioxide (CO2) permeability of approximately 1,000 cm at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 160,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 190,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 180,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 30°C. 3 / (m2 ×24h×atm) ~ approx. 170,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 160,000cm 3 / (m 2 It can have a carbon dioxide (CO2) permeability of 1000 kJ / cm² / hour (24h x 24h x atm).

[0026] The protective fluoropolymer layer has a resistance of at least 4,000 cm at 30°C. 3 / (m 2 The protective fluoropolymer layer may have a carbon dioxide permeability of at least 10,000 cm@3 at 30°C. 3 / (m 2 The protective fluoropolymer layer may have a carbon dioxide permeability of at least 25,000 cm@3 at 30°C. 3 / (m 2 The protective fluoropolymer layer may have a carbon dioxide permeability of at least 50,000 cm@3 at 30°C. 3 / (m 2 The protective fluoropolymer layer may have a carbon dioxide (CO2) permeability of at least 75,000 cm@2 at 30°C. 3 / (m 2 The protective fluoropolymer layer may have a carbon dioxide (CO2) permeability of at least 100,000 cm3 at 30°C. 3 / (m 2 It can have a carbon dioxide (CO2) permeability of 1000 kJ / cm² / hour (24h x 24h x atm).

[0027] The protective fluoropolymer layer has a resistance of approximately 1,000 cm at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm 3 / (m 2The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 4,000 cm@24 h at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 25,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 50,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 75,000 cm@24 h at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 190,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 180,000cm 3 / (m 2The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 170,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 30°C. 3 / (m 2 ×24h×atm) ~ approx. 160,000cm 3 / (m 2 It can have a carbon dioxide (CO2) permeability of 1000 kJ / cm² / hour (24h x 24h x atm).

[0028] The ventilation hole must be at least 4,000 cm at 60°C. 3 / (m 2 The vent may have a carbon dioxide (CO2) permeability of at least 10,000 cm@24h at 60°C. 3 / (m 2 The vent may have a carbon dioxide (CO2) permeability of at least 25,000 cm@2 at 60°C. 3 / (m 2 The vent may have a carbon dioxide (CO2) permeability of at least 50,000 cm@2 at 60°C. 3 / (m 2 The vent may have a carbon dioxide (CO2) permeability of at least 75,000 cm@2 at 60°C. 3 / (m 2 The vent may have a carbon dioxide (CO2) permeability of at least 100,000 cm@2 at 60°C. 3 / (m 2 The vent may have a carbon dioxide (CO2) permeability of at least 150,000 cm3 at 60°C. 3 / (m 2 It can have a carbon dioxide (CO2) permeability of 1000 kJ / cm² / hour (24h x 24h x atm).

[0029] The ventilation hole is approximately 1,000 cm at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 500,000cm 3 / (m 2 The vent has a carbon dioxide (CO2) permeability of approximately 4,000 cm@24h at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 500,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 500,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 25,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 500,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 50,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 500,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 75,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 500,000cm 3 / (m 2 The ventilation holes have a carbon dioxide (CO2) permeability of approximately 1,000 cm at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 450,000cm 3 / (m 2 The ventilation holes have a carbon dioxide (CO2) permeability of approximately 1,000 cm at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 400,000cm 3 / (m 2The ventilation holes have a carbon dioxide (CO2) permeability of approximately 1,000 cm at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 350,000cm 3 / (m 2 The ventilation holes have a carbon dioxide (CO2) permeability of approximately 1,000 cm at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 300,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 450,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 400,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 350,000cm 3 / (m 2 The vent can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 300,000cm 3 / (m 2 It can have a carbon dioxide (CO2) permeability of 1000 kJ / cm² / hour (24h x 24h x atm).

[0030] The protective fluoropolymer layer has a resistance of at least 4,000 cm at 60°C. 3 / (m 2 The protective fluoropolymer layer may have a carbon dioxide permeability of at least 10,000 cm@3 at 60°C. 3 / (m 2The protective fluoropolymer layer may have a carbon dioxide permeability of at least 25,000 cm@3 at 60°C. 3 / (m 2 The protective fluoropolymer layer may have a carbon dioxide permeability of at least 50,000 cm@3 at 60°C. 3 / (m 2 The protective fluoropolymer layer may have a carbon dioxide (CO2) permeability of at least 75,000 cm@2 at 60°C. 3 / (m 2 The protective fluoropolymer layer may have a carbon dioxide (CO2) permeability of at least 100,000 cm@2 at 60°C. 3 / (m 2 It can have a carbon dioxide (CO2) permeability of 1000 kJ / cm² / hour (24h x 24h x atm).

[0031] The protective fluoropolymer layer has a resistance of approximately 1,000 cm at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 4,000 cm@2 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 200,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 500,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 25,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 500,000cm 3 / (m 2The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 50,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 500,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 75,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 500,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 450,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 400,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 350,000cm 3 / (m 2 The protective fluoropolymer layer can have a carbon dioxide (CO2) permeability of approximately 10,000 cm3 at 60°C. 3 / (m 2 ×24h×atm) ~ approx. 300,000cm 3 / (m 2 It can have a carbon dioxide (CO2) permeability of 1000 kJ / cm² / hour (24h x 24h x atm).

[0032] The ventilation hole can have a CO2 permeability that is at least 60% of the CO2 permeability of the at least one protective fluoropolymer layer alone. The ventilation hole can have a CO2 permeability that is at least 65% of the CO2 permeability of the at least one protective fluoropolymer layer alone. The ventilation hole can have a CO2 permeability that is at least 70% of the CO2 permeability of the at least one protective fluoropolymer layer alone. The ventilation hole can have a CO2 permeability that is at least 75% of the CO2 permeability of the at least one protective fluoropolymer layer alone. The ventilation hole can have a CO2 permeability that is at least 80% of the CO2 permeability of the at least one protective fluoropolymer layer alone.

[0033] The vent can include at least two protective fluoropolymer layers and a bonding layer that bonds the two protective fluoropolymer layers together. The bonding layer can be a reinforcing layer. The vent can include at least two reinforcing layers, and the at least two protective fluoropolymer layers can be sandwiched between the at least two reinforcing layers.

[0034] The vent can include at least two reinforcing layers, and the at least one protective fluoropolymer layer can be sandwiched between the at least two reinforcing layers. The at least one protective fluoropolymer layer can permeate each of the at least two reinforcing layers.

[0035] The vent can have a burst pressure of at least 400 kPa at a 5 mm diameter, measured using the methods described herein. The vent can have a burst pressure of at least 450 kPa at a 5 mm diameter. The vent can have a burst pressure of at least 500 kPa at a 5 mm diameter.

[0036] The vent can be configured to be installed within the sealed container. The sealed container can be a battery housing. Thus, the vent can be suitable for use within the battery housing. The battery housing can be part of the battery. The battery can be a secondary battery. The secondary battery can be a lithium-ion battery. The battery can include a positive electrode and a negative electrode. The positive electrode can be selected from lithium nickel manganese cobalt oxide ("NMC"), lithium nickel cobalt aluminum oxide ("NCA"), lithium manganese oxide ("LMO"), lithium iron phosphate ("LFP"), lithium cobalt oxide ("LCO"), or any combination thereof. The negative electrode can be selected from lithium, graphite, lithium titanate ("LTO"), tin-cobalt alloy, or any combination thereof.

[0037] In some embodiments, the battery can include at least one separator, which can include at least one material selected from polypropylene, polyethylene, at least one tetrafluoroethylene (TFE) polymer or copolymer, at least one vinylidene fluoride homopolymer, at least one hexafluoropropylene (HFP)-vinylidene fluoride copolymer, or any combination thereof.

[0038] The electrolyte can be an electrolytic solution, and the electrolytic solution can include at least one solvent and at least one electrolyte salt. The at least one solvent of the electrolytic solution can include at least one organic solvent. The at least one organic solvent of the electrolyte can be selected from propylene carbonate, ethylene carbonate, diethyl carbonate (DEC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), or a mixture thereof.

[0039] The electrolyte can include at least one additive, and the at least one additive can be configured to release at least one gas selected from CO, H, CO, CH, or any combination thereof during operation of the battery. The at least one additive can be selected from the group including vinylene carbonate (VC), ethylene sulfite (ES), and fluoroethylene carbonate (FEC).

[0040] The electrolyte may be impregnated within at least one separator.

[0041] The sealed container can be a pouch. The sealed container can be a battery pouch. The sealed container is configured to hold a battery solution and can transfer ions from the first electrode to the second electrode through the battery solution. Thus, the sealed container can hold at least two electrodes and at least two electrical contacts configured to connect the at least two electrodes to an external electrical circuit. At least one container wall can be configured to be substantially impermeable to a fluid held within the sealed container. For example, the battery pouch can be a lithium (Li)-ion pouch cell.

[0042] At least one container wall of the plurality of container walls can be a rigid container wall. The rigid container wall can include a rigid polymer material. The rigid container wall can include a thermoplastic material. The rigid container wall can include a reinforced thermoplastic material. For example, the rigid container wall can include a thermoplastic material such as polypropylene (PP), polyethylene (PE), polybutylene terephthalate (PBT), or polyethylene terephthalate (PET) reinforced with fibers such as glass fibers. The rigid container can include a rigid metal material. The wall of the rigid container can include, for example, aluminum, steel, stainless steel, copper, brass, bronze, tin, or lead.

[0043] In a second aspect, there is provided a vent for use in a sealed container comprising at least one perfluoroalkoxyalkane (PFA) layer or at least one fluorinated ethylene propylene (FEP) layer and at least one ePTFE layer, wherein the at least one PFA layer or the at least one FEP layer at least partially penetrates the at least one ePTFE layer, and the at least one PFA layer or FEP layer has a thickness of 5 μm to 150 μm.

[0044] The vent includes at least two layers of ePTFE, and at least one layer of PFA or at least one layer of FEP can be sandwiched between the at least two layers of ePTFE.

[0045] The at least one PFA layer or the at least one FEP layer may be at least partially infiltrated into both of the at least two ePTFE layers.

[0046] The at least one PFA layer or the at least one FEP layer can have a thickness of 10 μm to 25 μm.

[0047] According to a third aspect, there is provided a method of manufacturing the vent of the first aspect, the method comprising: providing at least one reinforcing layer and at least one protective fluoropolymer layer; disposing the at least one reinforcing layer to at least partially occlude the at least one protective fluoropolymer layer; and applying heat and pressure to the at least one reinforcing layer; wherein the at least one protective fluoropolymer layer at least partially penetrates the at least one reinforcing layer.

[0048] The heat applied to the at least one reinforcing layer can correspond to subjecting the at least one reinforcing layer to a temperature of 100°C to 325°C. The heat applied to the at least one reinforcing layer can correspond to subjecting the at least one reinforcing layer to a temperature of 300°C to 325°C.

[0049] The pressure applied to the at least one reinforcing layer can be between 200 kPa and 10,000 kPa.

[0050] In a fourth aspect, there is provided a sealed container including a vent according to the first or second aspect, the sealed container including at least one wall, the wall including an opening, and the vent covering the opening.

[0051] The vent may cover the opening so that, during use, gas within the enclosure may escape from the enclosure through the opening and the vent.

[0052] The sealed container can be a battery housing. Accordingly, the vent can be suitable for use in the battery housing. The secondary battery can be a lithium ion battery.

[0053] The positive electrode can be selected from lithium nickel manganese cobalt oxide ("NMC"), lithium nickel cobalt aluminum oxide ("NCA"), lithium manganese oxide ("LMO"), lithium iron phosphate ("LFP"), lithium cobalt oxide ("LCO"), or any combination thereof.

[0054] The negative electrode can be selected from lithium, graphite, lithium titanate ("LTO"), tin-cobalt alloy, or any combination thereof.

[0055] In some embodiments, the battery can include at least one separator, which can include at least one material selected from polypropylene, polyethylene, at least one tetrafluoroethylene (TFE) polymer or copolymer, at least one vinylidene fluoride homopolymer, at least one hexafluoropropylene (HFP)-vinylidene fluoride copolymer, or any combination thereof.

[0056] The electrolyte can be an electrolytic solution, and the electrolytic solution can include at least one solvent and at least one electrolyte salt. The at least one solvent of the electrolytic solution can include at least one organic solvent. The at least one organic solvent of the electrolyte can be selected from propylene carbonate, ethylene carbonate, diethyl carbonate (DEC), dimethyl carbonate (DMC), or a mixture thereof.

[0057] The electrolyte can include at least one additive, and the at least one additive can be configured to release at least one gas selected from CO, H, CO, CH, or any combination thereof during operation of the battery. The at least one additive can be selected from the group including vinylene carbonate (VC), ethylene sulfite (ES), and fluoroethylene carbonate (FEC).

[0058] The electrolyte may be impregnated within at least one separator.

[0059] The sealed container can be a pouch.

[0060] The sealed container can be a battery pouch. The sealed container can be configured to hold a battery solution, which allows ions to migrate from the first electrode to the second electrode through the battery solution. Thus, the sealed container can hold at least two electrodes and at least two electrical contacts configured to connect the at least two electrodes to an external electrical circuit. At least one container wall can be configured to be substantially impermeable to a fluid held within the sealed container. For example, the battery pouch can be a lithium (Li)-ion pouch cell.

[0061] At least one container wall of the plurality of container walls can be a rigid container wall. The rigid container wall can include a rigid polymer material. The rigid container wall can include a thermoplastic material. The rigid container wall can include a reinforced thermoplastic material. For example, the rigid container wall can include a thermoplastic material such as polypropylene (PP), polyethylene (PE), polybutylene terephthalate (PBT), or polyethylene terephthalate (PET) reinforced with fibers such as glass fibers. The rigid container can include a rigid metal material. The rigid container wall can include, for example, aluminum, steel, stainless steel, copper, brass, bronze, tin, or lead.

[0062] The features of the vents of the first and second embodiments are the features of the vents of the third and fourth embodiments. [Brief explanation of the drawings]

[0063] BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the present invention will now be described, by way of non-limiting example, with reference to the accompanying drawings, in which:

[0064] [Figure 1] FIG. 1 is a plot of the gas transmission rate (GTR) and CO2 transmission rate of vent materials at A) 30°C and B) 60°C.

[0065] [Figure 2] FIG. 2 is a plot of burst pressure as a function of PFA film thickness.

[0066] [Figure 3] FIG. 3 is a cross section of a vent according to an embodiment.

[0067] [Figure 4] FIG. 4 is a cross section of a vent over an opening according to an embodiment.

[0068] [Figure 5] FIG. 5 is a scanning electron microscope (SEM) side view of a vent according to an embodiment.

[0069] [Figure 6] FIG. 6 is a plot of burst pressure of vents according to embodiments on 5 mm and 16 mm diameter openings for vents containing A) a 12 μm PFA layer and B) a 25 μm PFA layer.

[0070] [Figure 7] FIG. 7 is a plot of the burst pressure of vents according to embodiments on 5 mm and 16 mm diameter openings compared to the protective fluoropolymer layer alone.

[0071] [Figure 8] FIG. 8 is a plot of CO 2 permeability (GTR) as a function of selectivity for the vent hole and protective fluoropolymer layer alone according to an embodiment at A) 30° C. and B) 60° C.

[0072] [Figure 9] FIG. 9 is a schematic side view of a manufacturing process for a reinforced vent according to an embodiment.

[0073] [Figure 10] FIG. 10 is a plot of vent burst pressure according to an embodiment for 12 μm vent diameter openings of 5 mm and 16 mm.

[0074] [Figure 11] FIG. 11 is a plot of CO 2 permeability (GTR) as a function of selectivity for vent holes and a protective fluoropolymer layer only according to an embodiment at A) 30° C. and B) 60° C.

[0075] [Figure 12] FIG. 12 is a cross section of a vent according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0076] Detailed Description While the making and use of various embodiments of the invention are described in detail below, it should be understood that the invention provides many applicable inventive concepts that can be embodied in a variety of specific contexts. The specific embodiments described herein are merely illustrative of specific ways to make and use the invention and do not limit the scope of the invention.

[0077] To facilitate understanding of the present invention, several terms are defined below. Terms defined herein have meanings commonly understood by one of ordinary skill in the art relevant to the present invention. Terms such as "a," "an," and "the" do not refer to only a single entity, but include general classes of which specific examples can be used for illustration. While terms herein are used to describe particular embodiments of the present invention, their use does not limit the present invention, except as outlined in the claims.

[0078] Test Method CO2 permeability measurement method -Examples 1 to 6 The CO2 permeability was measured using a gas detector (GTR Tech, model number GTR-11MJGG). The sample vent was placed in the evaluation cell, measuring 15.2 cm2. 2 The CO2 is supplied to the evaluation cell at a temperature of 30°C to 60°C and a supply pressure of 99 kPa for 0.1 to 10 minutes.

[0079] Examples 7 and 9 The CO2 permeability was measured using a gas detector (Labthink model number VAC-V2). The sample vent was placed in the evaluation cell and measured over an area of ​​38.48 cm2. 2 The CO2 supply is supplied to the evaluation cell at a temperature of 30°C to 60°C and a supply pressure of 1 atm.

[0080] Moisture permeability measurement method Moisture (gaseous HO) permeability was measured by dividing the chamber into a high humidity section containing liquid water and a low humidity section with a sample vent, flowing dry gas across the sample vent, and measuring the humidity in the low humidity section. The exposed sample vent area was 5.0 × 10 -3 m 2 It was.

[0081] How to calculate CO2 vs. H2O selectivity The CO2 to H2O selectivity of the sample vent was determined by the gas permeability (GTR) of the sample vent for CO2 (unit: cm 3 / (m 2 × 24h × atm) and the moisture permeability of the sample vent hole / (MVTR, unit: g / (m 2 × days)) and the permeability coefficient (CO2: unit is cm 3 / (cm 2 × seconds × cmHg, moisture: unit is g / (cm 2 The selectivity is calculated by dividing the CO2 permeability coefficient by the water permeability coefficient.

[0082] Burst pressure measurement method The burst pressure of the sample vent was measured by mounting the sample vent under a support screen. The support screen defines an opening of either 5 mm or 11 mm diameter. Water is directed at the opening at a pressure of 550 kPa for 30 minutes. The time it takes for the sample vent to burst at this pressure is recorded.

[0083] Vents in sealed containers that hold water-sensitive liquids, such as batteries or battery pouches, need to be able to vent waste gases, such as carbon dioxide, from the sealed container while preventing the ingress of water liquid and water vapor into the sealed container.

[0084] For a battery or battery pouch, it is important that the vent comprise a material that is highly permeable to carbon dioxide so that carbon dioxide generated within the battery or battery pouch can escape from the sealed container through the vent. However, the vent must comprise a material that is substantially impermeable to the ingress of water vapor. Thus, the vent material must be able to selectively allow carbon dioxide to escape through the vent while preventing the ingress of water.

[0085] Examples of materials known to be permeable to carbon dioxide and impermeable to water include fluoropolymers such as PFA and FEP. The carbon dioxide permeability of a material at a given temperature is typically a function of the thickness of the material. For example, the permeability ("gas transmission rate" or GTR) of PFA, FEP, and ePTFE (labeled DM18C) is shown in Figure 1. Therefore, in the case of a vent, it is desirable to make the vent material as thin as possible to maximize the permeability of the material.

[0086] However, when pressure builds up inside the sealed container during use, the vent material must also be able to withstand the pressure exerted on it. Thin fluoropolymer layers typically cannot withstand significant pressure. The burst pressure of PFA is shown as a function of thickness in Figure 2.

[0087] Therefore, vents typically used in this field use thicker layers or films of fluoropolymer to ensure structural stability at the expense of permeability, or contain other fluoropolymers such as expanded polytetrafluoroethylene (ePTFE) or densified ePTFE (i.e., expanded PTFE that has been densified after the original PTFE has been stretched).

[0088] Example 1 (BZ8 / PFA12 / BZ8) 3, reinforced vent 1 (functioning as a vent) includes PFA layer 2 (functioning as a protective fluoropolymer layer), first ePTFE layer 4 (functioning as a first reinforcing layer), and second ePTFE layer 6 (functioning as a second reinforcing layer). PFA layer 2 is provided sandwiched between first ePTFE layer 4 and second ePTFE layer 6, with PFA layer 2 penetrating the pores of first ePTFE layer 4 and second ePTFE layer 6.

[0089] PFA layer 2 was 12 μm thick and comprised PFA Neoflon A provided by Daikin Japan. First ePTFE layer 4 and second ePTFE layer 6 were both 8 μm thick and comprised ePTFE provided by WLGore & Associates, Inc.

[0090] Referring to Figure 9, a reinforced vent 1 was created by placing a PFA layer 2 between a first ePTFE layer 4 and a second ePTFE layer 6 to form a stack, and the stack was placed on a first plate 20. A second plate 22 was placed on top of the stack. The first and second plates were heated, the stack was heated to 300°C, and a pressure of 6500 kPa was applied to the stack. The PFA layer 2 at least partially melted and infiltrated the pores of the first ePTFE layer 4 and the second ePTFE layer 6.

[0091] FIG. 4 shows a side view of a reinforcing vent 1 above an opening 8 of a sealed container.

[0092] Figure 5 shows an SEM image of reinforced vent 1. In this image, PFA can be seen to have infiltrated the ePTFE.

[0093] Example 2 (BZ8 / PFA25 / BZ8) An alternative reinforced vent includes a 25 μm thick PFA layer, a first 8 μm thick ePTFE layer, and a second 8 μm thick ePTFE layer.

[0094] Example 3 (BZ8 / FEP12 / BZ8) Yet another reinforced vent includes a 12 μm thick FEP layer, a first 8 μm thick ePTFE layer, and a second 8 μm thick ePTFE layer.

[0095] Example 4 (SP25 / PFA12 / SP25) Yet another reinforced vent includes a 12 μm thick PFA layer, a 25 μm thick first ePTFE layer, and a 25 μm thick second ePTFE layer.

[0096] Example 5 (BZ8 / PFA12 / BZ8) Yet another reinforced vent includes a 12 μm thick PFA layer, a first 8 μm thick ePTFE layer, and a second 8 μm thick ePTFE layer.

[0097] Example 6 (PFA12 / BZ8) Referring to Figure 12, yet another reinforced vent 100 includes a 12µm thick PFA layer 102 and a single 8µm thick ePTFE layer 104 on only one side.

[0098] The example reinforced vents were tested to determine the burst pressure, CO2 permeability and selectivity of each reinforced vent.

[0099] As shown in Figures 6 and 7, the example reinforced vents had significantly superior burst pressures compared to the protective fluoropolymer layer alone (PFA or FEP).

[0100] FIG. 8 shows that the selectivity versus CO2 permeability is comparable to that of the protective fluoropolymer layer alone.

[0101] [Table 1]

[0102] The CO2 permeabilities of Examples 8 and 10 were calculated from the measurements of Examples 7 and 9, respectively.

[0103] A comparison of the CO2 permeability and CO2 / H2O selectivity of skived fluoropolymer materials (Examples 7 and 8, trade name DeWAL DW200) that can be used as protective fluoropolymer layers expected to benefit from the reinforcement structure of the present disclosure is shown in the table and compared to the properties of PFA films (Examples 9 and 10, Neoflon PFA). The permeability of a 150 μm thick layer was calculated from the values ​​of 61 μm or 100 μm, respectively, using the following formula: "Variations in membrane thickness changed the permeability, but did not change the separation properties of the polymer" (McKeen, Laurence W., Permeation Properties of Plastics and Elastomers: A Permeation Reference Guide and Databook, Elsevier Science & Technology Books, 2016).

[0104]

number

[0105] While the present invention has been described above with respect to certain preferred embodiments, it will be apparent that many various changes and modifications can be made to other embodiments in the shape, design, construction and arrangement of parts without departing from the present invention, and it will be understood that all such changes and modifications are considered embodiments that are part of the present invention as defined in the appended claims.

Claims

1. at least one protective fluoropolymer layer and at least one reinforcing layer, wherein said at least one protective fluoropolymer layer at least partially penetrates said at least one reinforcing layer, and said at least one protective fluoropolymer layer has a viscosity of at least 600 cm@3 at 30°C as measured using the method described herein. ３ / g of carbon dioxide (CO ２ ) versus water (H ２ O) Selectivity, and at least 1,000 cm at 30°C ３ / (m ２ × 24h × atm) CO ２ A vent for use in a closed container, having a permeability.

2. The vent of claim 1, wherein the at least one protective fluoropolymer layer has a thickness of from 5 μm to 150 μm.

3. The at least one protective fluoropolymer layer has a CO ２ Permeability of at least 4,000 cm at 30°C ３ / (m ２ 3. The vent hole according to claim 1 or claim 2, wherein the tensile strength is 24 h x 24 h x atm.

4. The at least one protective fluoropolymer layer has a CO ２ Permeability of at least 10,000 cm at 30°C ３ / (m ２ 4. The vent of claim 3, wherein the tensile strength is 24 h x 24 h x atm.

5. The vent of any one of claims 1 to 4, wherein the at least one protective fluoropolymer layer comprises a fluoropolymer having a melting point below 320°C.

6. 6. The vent of any one of claims 1 to 5, wherein the at least one protective fluoropolymer layer comprises a fluoropolymer selected from the group consisting of perfluoroalkoxyalkane (PFA), fluorinated ethylene propylene (FEP), polyvinyl fluoride (PVF), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), or polyethylenetetrafluoroethylene (ETFE).

7. The vent of any preceding claim, wherein the at least one reinforcing layer is porous.

8. The vent of any one of claims 1 to 7, wherein the vent comprises at least two reinforcing layers, a protective fluoropolymer layer sandwiched between the at least two reinforcing layers.

9. The ventilation hole has a width of at least 800 cm at 30°C. ３ The vent of any one of claims 1 to 8, having a carbon dioxide to water vapor selectivity of 1 / g.

10. 10. The vent of claim 9, wherein the vent includes at least two reinforcing layers, the at least two protective fluoropolymer layers sandwiched between the at least two reinforcing layers.

11. providing at least one reinforcing layer and at least one protective fluoropolymer layer; disposing the at least one reinforcing layer to at least partially occlude the at least one protective fluoropolymer layer; and applying heat and pressure to the at least one reinforcing layer; The process includes the steps of: The method of any preceding claim, wherein the at least one protective fluoropolymer layer at least partially penetrates the at least one reinforcing layer.

12. 12. The method according to claim 11, wherein the heat applied to the at least one reinforcing layer corresponds to applying a temperature of between 100°C and 325°C, preferably between 300°C and 325°C.

13. 11. A sealed container comprising an opening and the vent hole of any one of claims 1 to 10, wherein the vent hole covers the opening such that gas within the sealed container can escape from the sealed container through the opening and the vent hole during use.

14. The enclosure of claim 13, wherein the enclosure is a battery.

15. 15. The enclosure of claim 13 or claim 14, wherein the enclosure comprises at least one flexible wall.

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