CELGARD, LLC

In accordance with at least selected embodiments, the present disclosure or invention is directed to improved or novel separators, cells, batteries, and/or methods of manufacture and/or use. In accordance with at least certain embodiments, the present disclosure or invention is directed to improved or novel separators such as a separator for a high energy and/or high voltage lithium ion battery which is stable up to a 4.5 volt, or preferably up to a 5.0 volt or higher charging voltage, such as a novel or improved single or multilayer or multiply microporous separator membrane. In accordance with at least selected embodiments, the present application or invention is directed to novel or improved porous membranes or substrates, separator membranes, separators, composites, electrochemical devices, batteries, cells, methods of making such membranes or substrates, separators, cells, and/or batteries, and/or methods of using such membranes or substrates, separators, cells, and/or batteries. In accordance with at least certain embodiments, the present application is directed to novel or improved microporous membranes, battery separator membranes, separators, energy storage devices, batteries including such separators, methods of making such membranes, separators, and/or batteries, and/or methods of using such membranes, separators and/or batteries. In accordance with at least certain selected embodiments, the present invention is directed to a novel or improved separator membrane or separator with or without embedded particles or materials, such as ceramic particles or materials, for example, aluminum oxide, boehmite, and/or barium, and/or with or without novel polymers, such as PVDF or PMP, and/or with or without one or more ceramic coatings, for a battery which is stable up to at least 5 volts in a battery, a novel or improved polymer membrane, or polymeric microporous membrane, adapted for use in a 4.5 volt, 4.7 volt, or 5 volt or higher rechargeable or secondary lithium battery and/or which provides for the energy density of a battery to be increased and/or has excellent oxidation resistance. In accordance with at least particular embodiments, the battery separator membrane described herein is directed to a single or multilayer or composite microporous membrane battery separator which may have excellent oxidation resistance and/or may be stable in a high voltage lithium battery system up to 5 volts or more.

Disclosed herein are battery separators that include a microporous membrane and a coating. The coating may comprise, consist, or consist essentially of polymeric components, inorganic components, or combinations thereof. The battery separators described herein are, among other things, thinner, stronger, and more wettable with electrolyte than some prior battery separators. The battery separators may be used in secondary or rechargeable batteries, including lithium ion batteries. The batteries may be used in vehicles or devices such as cell phones, tablets, laptops, and e-vehicles.

A multilayer microporous membrane which includes microlayers and one or more lamination barriers is disclosed. Also disclosed is a battery separator or battery comprising one or more of the multilayer microporous films or membranes. Also, described herein is a method for making multilayer microporous separators, membranes or films.

A ceramic-coated battery separator exhibiting improved safety has the following structure: a battery separator; and a ceramic coating that comprises ceramic micro-wires. The ceramic coating may comprise ceramic micro-wires as the only ceramic material, or may comprise a mixture of ceramic micro-wires and ceramic particles.

A coated battery separator, comprising the battery separator; and a porous coating on at least one side of the battery separator, wherein the porous coating comprises a polymer comprising an amide functional group.

Systems and methods of evaluating the electrochemical stability of material are provided comprising providing an electrochemical cell having a tube cell, electrolyte material, and at least one reference electrode and at least one working electrode. The working electrode can be at least one of aluminum and copper foil. In some instances, the working electrode can be coated with a test material. In some other instances, the electrolyte material can be pretreated with a test material. The electrochemical cell can be subjected to a cyclic voltammetry procedure in part to determine physical and/or chemical attributes of the test material.

The problems or issues faced by typical larger SSE batteries are solved by providing an interface or interfacial layer at least between the anode, which comprises Li or Na, and the solid state electrolyte (SSE). In some other embodiments, an interfacial layer may be provided between the anode, which comprises Li or Na, and the SSE, and an interface or interfacial layer may also be provided between the cathode and the SSE. In at least selected embodiments, aspects or objects, the interfacial layer may act as a shock absorber between a SSE (e.g., a sulfide glass SSE) and an anode material that is soft compared to the SSE (e.g., Li metal). In other embodiments, the interfacial layer may act as a shock absorber between the SSE and a cathode material that is softer than the SSE. In at least certain embodiments, the interfacial layer may improve ionic conductance between the anode and the SSE and/or the SSE and the cathode. In at least certain selected embodiments, the interfacial layer may prevent or deter lithium deposition and dendrite growth at the interface between the anode and the SSE. Interface defects at the interface between the anode and the SSE may allow lithium deposition and dendrite growth. The dendrites may continue to grow through cracks in the SSE causing a short, which is a safety issue. The inventive interfacial layer between the anode and the SSE may prevent or deter this. In at least some embodiments, the interfacial layer may be a porous polymer layer filled with liquid electrolyte and may improve ionic conductance between the anode and the SSE and/or the SSE and the cathode. In certain embodiments, the anode interface or interfacial layer may be a porous polymer layer filled with liquid electrolyte. In some embodiments, the cathode interface or interfacial layer may be a porous polymer layer filled with liquid, gel or polymer electrolyte.

A microporous film having at least one of the following properties: unrestrained MD shrinkage, when the film is baked unrestrained at 90° C. for 1 hour, of 2% or more; unrestrained MD shrinkage, when the film is baked unrestrained at 105° C. for 1 hour, of 2.5% or more; MD restrained growth, when measured using the MD restrained growth test, of less than or equal to 0.2%; rebound or recovery of 5% or greater when measured by the compressibility test; a max compression greater than or equal to 18% when measured by the compressibility test; swelling in DEC when measured according to the swelling in DEC test of 0.95% or less; the film exhibits a round-shaped, not a slit-shaped opening when subjected to the puncture test; the lamellae of the film have a thickness no greater than 250 nm; a normalized puncture strength above 350 g/16 micron; and having higher modulus and lower elongation before break of less than 40% in the machine direction. Also disclosed is a battery separator, battery, or device comprising at least one microporous film as described herein.

In accordance with at least selected embodiments, a battery separator or separator membrane comprises one or more co-extruded multi-microlayer membranes optionally laminated or adhered to another polymer membrane. The separators described herein may provide improved strength, for example, improved puncture strength, particularly at a certain thickness, and may exhibit improved shutdown and/or a reduced propensity to split.

A system for differentiating short circuiting in a battery includes: a detector coupled to the battery; a monitor in communication with the detector, the monitor including a profile of a battery shorting behavior, and a comparator for matching data from the detector to the profile; and a controller for taking action based upon information from the detector. A method for detecting short circuiting in a battery includes the steps of: detecting a behavior of the battery; comparing the behavior of the battery to a predetermined battery behavior profile; determining the type of short based on the comparison; and taking mitigating action based on the determination. The system/method may monitor temperature of the battery, heat generation from the battery, current flow through the battery, voltage drop across the battery, and/or combinations thereof. The system/method discriminates between the various battery shorting behaviors for aggressive response or passive response.