CELGARD, LLC

A ceramic-coated battery separator having a microporous polyolefin membrane and a ceramic coating on at least one surface of the microporous polyolefin membrane, wherein the ceramic-coated separator exhibits a strain shrinkage of 0% at temperatures greater than or equal to 120 degrees Celsius is provided.

A multilayer membrane comprising at least two co-extruded layers where the two co-extruded layer contain different polymers and one of the two co-extruded layers contains an extrusion additive. Examples of useful extrusion additives may include a nucleating agent or a pore-forming particulate. A method for making the membrane is also disclosed. Using an extrusion additive when co-extruding two different polymers avoids some of the drawbacks associated with processes involving the co-extrusion of different polymers, particularly processes where a co-extruded non-porous precursor is later stretched to form pores. For example, the drawback of lower permeability, difficulty to make lower Gurley, and splittiness may be improved.

[Problem] To provide a separator for electric storage devices that suppresses dendrite short circuits and has excellent thermal stability. [Solution] Provided is a separator for electric storage devices including: (A) a microporous layer mainly composed of (X) isotactic polypropylene; and (B) a microporous layer containing (Y) isotactic polypropylene identical or different from the isotactic polypropylene (X), and (Z) thermoplastic resin different from the isotactic polypropylene (Y). The microporous layer (B) has a lower isotactic polypropylene content than the microporous layer (A), and the thermoplastic resin (Z) has a tensile modulus of from 3 MPa to 500 MPa.

Novel or improved microporous battery separator membranes, separators, cells, batteries including such membranes, separators, or cells, and/or methods of making such membranes and/or separators, and/or methods of using such membranes and/or separators. In accordance with at least certain embodiments, an improved or novel battery separator for a secondary or rechargeable lithium battery may have low Electrical resistance of less than 0.95 ohm-cm 2 , or in some cases, less than 0.8 ohm-cm 2 . Furthermore, the inventive battery separator membrane may provide a means to achieve an improved level of battery performance in a rechargeable or secondary lithium battery based on a possibly synergistic combination of low Electrical resistance, low Gurley, low tortuosity, and/or a unique trapezoid shaped pore. In accordance with at least certain multilayer embodiments (by way of example only, a trilayer membrane made of two polypropylene layers with a polyethylene layer in between), the inventive microporous membrane or battery separator may have excellent onset and rate of thermal shutdown performance.

Several embodiments of a microporous battery separator for lithium rechargeable batteries and/or related methods of making and/or using such separators are disclosed. A dry process battery separator or membrane separator exhibits a thickness that is less than about 14 μm and has increased strength performance as defined by reduced splittiness. The mode of splitting failure has been investigated, and the improvement in splittiness quantified by a test method known as the Composite Splittiness Index (CSI).

The present invention relates to surface modifying agents for polymeric and/or textile materials, methods of making and/or using a surface modifying agent to modify and functionalize polymeric and/or textile materials, and/or methods of using surface modified or functionalized polymeric and textile materials, and/or products using or incorporating surface modified or functionalized polymeric and textile materials. For example, the surface modifying agent in precursor form can be styrene sulfonyl azide monomer, polymer or copolymer capable of undergoing a chemical reaction in the presence of heat or light to form one or more styrene sulfonated nitrene monomers, polymers or copolymers, which are capable of chemically reacting with the surface of a polymeric or textile material to endow a specific or desired chemical surface functionality to the surface of a polymeric or textile material. Furthermore, the present invention is possibly preferably directed to a surface modifying agent which comprises a styrene sulfonated nitrene monomer, polymer or polymer containing one or more nitrene functional groups, which are capable of chemically reacting via an insertion reaction into one or more carbon-hydrogen bonds on the surface of a polymeric or textile material in order to chemically attach a specific or desired chemical functionality to the surface of a polymeric or textile material.

The present invention is preferably directed to a polylactam ceramic coating for a microporous battery separator for a lithium ion secondary battery and a method of making this formulation and application of this formulation to make a coated microporous battery separator. The preferred inventive coating has excellent thermal and chemical stability, excellent adhesion to microporous base substrate, membrane, and/or electrode, improved binding properties to ceramic particles and/or has improved or excellent resistance to thermal shrinkage, dimensional integrity, and/or oxidation stability when used in a rechargeable lithium ion battery.

A secondary battery that generates or includes metal-ion contaminants selected from copper ions, manganese ions, nickel ions, cobalt ions, iron ions, aluminum ions, chrome ions, molybdenum ions, tin ions or combinations thereof, the battery comprising: an anode; a cathode; a coated or uncoated battery separator between the anode and the cathode, wherein the coated or uncoated battery separator comprises a trap layer; and an electrolyte. The battery improve yield rate of initial charge and aging process and exhibits prolonged useful life due to the separator, which reduces or eliminates metal-ion contamination in the battery.

Novel or improved microporous single or multilayer battery separator membranes, separators, batteries including such membranes or separators, methods of making such membranes, separators, and/or batteries, and/or methods of using such membranes, separators and/or batteries are provided. In accordance with at least certain embodiments, a multilayer dry process polyethylene/polypropylene/polyethylene microporous separator which is manufactured using the inventive process which includes machine direction stretching followed by transverse direction stretching and a subsequent calendaring step as a means to reduce the thickness of the multilayer microporous membrane, to reduce the percent porosity of the multilayer microporous membrane in a controlled manner and/or to improve transverse direction tensile strength. In a very particular embodiment, the inventive process produces a thin multilayer microporous membrane that is easily coated with polymeric-ceramic coatings, has excellent mechanical strength properties due to its polypropylene layer or layers and a thermal shutdown function due to its polyethylene layer or layers. The ratio of the thickness of the polypropylene and polyethylene layers in the inventive multilayer microporous membrane can be tailored to balance mechanical strength and thermal shutdown properties.

Described herein is a multilayer microporous film or membrane that may exhibit improved properties, including improved dielectric break down and strength, compared to prior monolayer or tri-layer microporous membranes of the same thickness. The preferred multilayer microporous membrane comprises microlayers and one or more lamination barriers. Also disclosed is a battery separator or battery comprising one or more of the multilayer microporous films or membranes. The inventive battery and battery separator is preferably safer and more robust than batteries and battery separators using prior monolayer and tri-layer microporous membranes. Also, described herein is a method for making the multilayer microporous separators, membranes or films described herein.