Abstract: An optimized electrochemical cell comprised of a housing divided into two chambers, a first chamber containing a protogenous, ion-conducting liquid and a positive high density electrode including a first active material and a porous binder, surrounded by a surface in which the porosity level increases towards the surface, a second chamber containing an aprotic, ion conducting liquid and a negative high density electrode including a second active material and a porous binder, surrounded by a surface in which the porosity level increases towards the surface. A symmetric, strong, highly porous, microporous polymer membrane divides the housing into the first and second chamber. The porosity level of the polymer membrane is 25% greater than the porosity level at the surface of the positive and negative high density electrodes.

Abstract: A porous membrane may have a high concentration of spherical fillers with a polymer binder. The polymer binder may have an affinity for the filler materials and may hold the filler materials together in a porous structure with high tortuosity and consistent pore size. The membrane may be manufactured with a reinforcing web, such as non-woven web. The membrane may be greater than 50% porous with a less than 1 micron pore size. Within the pore walls that may be less than 0.02 microns in width, a densely packed filler material may have an average diameter of less than 0.005 microns.

Abstract: A microporous membrane may be manufactured using a polymer binder and a filler material using a liquid pore forming agent having a surface free energy that is lower than that of the filler and higher than that of the polymer. The repulsion of the pore forming agent to the polymer may form the pores of the membrane, while the attraction of the polymer to the filler may encapsulate the filler into the structure of the membrane. The filler may be particles that are on the order of or smaller than the wall thickness of the microporous structure.

Abstract: A porous membrane may be manufactured with a high content of filler material and a polymer binder. After forming the membrane, the membrane may be post processed to reform the polymer binder into a stronger yet still porous membrane. The post processing may include bringing the membrane above the melt temperature of the polymer or by immersing the membrane in a solvent. Photomicrographs show that the structure may change, yet the performance of the material in batteries and other electrochemical cells may remain the same or even improve.

Abstract: A non-woven mat may be generated using synthetic wood pulp and short glass fibers. The non-woven mat may be made in very thin, light weight configurations for various uses. The synthetic wood pulp may serve as a dispersant to disperse the glass fibers in a mixture prior to using paper making techniques to form the mat. A heat flux may bind the glass fibers by melting the synthetic wood pulp to form a mat. The mat may be calendered. In some embodiments, the mat may have a secondary application of a polymer, such as PVDF or PMMA which may further strengthen the mat.

Abstract: The present invention provides microporous polymers and methods for producing and using the same. In particular, microporous polymers of the present invention are highly porous as indicated by a Gurley air permeability flow rate of about 4 seconds or less per mL of air flow per 25 micron of microporous polymer thickness per square inch.

Abstract: A microporous battery separator may be laminated to electrodes and manipulated through manufacturing on a continuous roll of material. Batteries may be constructed by layering the laminated electrodes and separator into various configurations, including flat and wound cell batteries. The separator may or may not contain a nonwoven or other reinforcement, and may be laminated to the electrodes using several different methods.

Abstract: The present invention provides microporous polymers and methods for producing and using the same. In particular, microporous polymers of the present invention are highly porous as indicated by a Gurley air permeability flow rate of about 4 seconds or less per mL of air flow per 25 micron of microporous polymer thickness per square inch.

Abstract: A battery separator may be formed with hard spacers made from ceramic and other high temperature materials. The spacers may be incorporated into a microporous membrane so that the microporous matrix may capture and hold the spacers. The spacers may be solid or hollow glass beads that are in the range of 30% to 100% of the thickness of the separator, and may comprise less than 10 weight percent. The resulting membrane may be largely microporous, and the separators may help battery electrodes to remain physically separated, even after internal temperatures exceed the melt temperature of the separator.

Abstract: A microporous polymer used as a battery separator may be formed with hard, insoluble dielectric spacer materials in fibrous or particulate form. The spacer materials may form a barrier when the battery separator may melt or be crushed during an over-temperature event, possibly preventing a fire. The spacer materials may be located within the polymer matrix and may be added to a solution used to form the microporous polymer.

Abstract: A porous material manufactured Polyvinylidene Difluoride, or PVDF may be used in several configurations as a separator material for Lithium Ion and other types of batteries. The PVDF separator may be used with electrodes manufactured from a PVDF substrate for various lamination techniques in various configurations. The PVDF separator may be used in several configurations to enable more active material into a given battery construction, ensure better adhesion between layers, and overall increase the performance and capacity of a battery.

Abstract: The present invention is directed to methods of producing a symmetric, strong, highly porous, microporous polymer film by (a) forming a layer of a polymer solution on a substrate, the solution comprising two miscible liquids and a polymer material dissolved therein, and wherein the first liquid has a surface tension lower than the surface energy of the polymer and the second liquid has a surface tension greater than the surface energy of the polymer; (b) producing a film of gelled polymer from the layer of polymer solution; and (c) rapidly removing the liquid from the film of gelled polymer by unidirectional mass transfer without dissolving the gelled polymer.