In one embodiment of the present invention, it is provided a method of manufacturing a separator comprising:

preparing expansion graphite; pulverizing the expansion graphite; mixing the expansion graphite and polymer; and forming a separator by molding the mixture.

In one embodiment of the present invention, it is provided a method of manufacturing a separator comprising:

preparing expansion graphite; pulverizing the expansion graphite; mixing the expansion graphite and polymer; and forming a separator by molding the mixture.

Provided is a microporous film which has a surface A and a surface B opposite to the surface A. In one embodiment, the microporous film has a ratio (F.sub.B/F.sub.A) of a dynamic friction coefficient F.sub.B of the surface B to a dynamic friction coefficient F.sub.A of the surface A of 1.2 to 20. In another embodiment, the microporous film is a single layer having a thickness of 3-18 μm, a number N.sub.A of pores on the surface A is 10-100/μm.sup.2, a number N.sub.B of pores on the surface B is 20-200/μm.sup.2, and N.sub.A/N.sub.B is 0.2-0.96. In addition, a total area S.sub.A of pores on the surface A is 0.02-0.5 μm.sup.2/μm.sup.2, a total area S.sub.B of pores on the surface B is 0.01-0.3 μm.sup.2/μm.sup.2, and S.sub.A/S.sub.B is 1.1-10. Furthermore, in another embodiment, a number W.sub.B of protrusion-like bodies on the surface B is 0.2-1000/100 μm.sup.2.

The present invention relates to a battery cell for evaluating an internal short circuit, and a method for evaluating using the battery cell, wherein an internal short circuit state of a battery cell can be easily induced and, at the same time, an effective internal short circuit evaluation is possible, and the battery cell comprising: first and second electrodes which comprise a coated region on which an electrode mixture layer is coated on a metal current collector and a non-coated region on which an electrode mixture layer is not coated, and which comprise first and second electrode tabs which protrude in one direction from the coated region and do not have an electrode mixture layer coated thereon.

The present invention relates to a battery cell for evaluating an internal short circuit, and a method for evaluating using the battery cell, wherein an internal short circuit state of a battery cell can be easily induced and, at the same time, an effective internal short circuit evaluation is possible, and the battery cell comprising: first and second electrodes which comprise a coated region on which an electrode mixture layer is coated on a metal current collector and a non-coated region on which an electrode mixture layer is not coated, and which comprise first and second electrode tabs which protrude in one direction from the coated region and do not have an electrode mixture layer coated thereon.

A separator for a rechargeable battery includes a porous substrate and a heat resistance layer on at least one surface of the porous substrate. The heat resistance layer includes an acryl-based copolymer, an alkali metal, and a filler. The acryl-based copolymer includes a unit derived from (meth)acrylate or (meth)acrylic acid, a cyano group-containing unit, and a sulfonate group-containing unit.

Separators, high performance electrochemical devices, such as, batteries and capacitors, including the aforementioned separators, systems and methods for fabricating the same. In one implementation, a separator is provided. The separator comprises a polymer substrate (131), capable of conducting ions, having a first surface and a second surface opposing the first surface. The separator further comprises a first ceramic-containing layer (136), capable of conducting ions, formed on the first surface. The first ceramic-containing layer (136) has a thickness in arrange from about 1,000 nanometers to about 5000 nanometers. The separator further comprises a second ceramic-containing layer (138), capable of conducting ions, formed on the second surface. The second ceramic-containing layer (138) is a binder-free ceramic-containing layer and has a thickness in arrange from about 1 nanometer to about 1,000 nanometers.

Electrolyte-infiltrated composite electrode includes an electrolyte component consisting of a polymer matrix with ceramic nanoparticles embedded in the matrix to form a networking structure of electrolyte. Suitable ceramic nanoparticles have the basic formula Li.sub.7La.sub.3Zr.sub.2O.sub.12 (LLZO) and its derivatives such as Al.sub.xLi.sub.7-xLa.sub.3Zr.sub.2-y-zTa.sub.yNb.sub.zO.sub.12 where x ranges from 0 to 0.85, y ranges from 0 to 0.50 and z ranges from 0 to 0.75, wherein at least one of x, y and z is not equal to 0. The networking structure of the electrolyte establishes an effective lithium-ion transport pathway in the electrode and strengthens the contact between electrode layer and solid-state electrolyte resulting in higher lithium-ion electrochemical cell's cycling stability and longer battery life. Sold-state electrolytes incorporating the ceramic particles demonstrate improved performance. Large dimensional electrolyte-infiltrated composite electrode sheets can be used in all solid-state lithium electrochemical pouch cells which can be assembled into battery packs.

The present invention relates to a porous film including polyethylene and pore-forming particles, wherein the porous film has a structure including lamella and fibril, and the average size of pores located inside the porous film is larger than the average size of pores located on the surface of the porous film; a separator including the same; and an electrochemical cell.

A separator for a lithium-containing electrochemical cell is provided herein. The separator includes a porous substrate having a first side and an opposing second side and a coating layer disposed adjacent to at least the first side of the porous substrate. The coating layer includes three-dimensionally (3D) ordered porous ceramic particles. An electrochemical cell including such a separator is also provided herein. The electrochemical cell may or may not include a negative electrode.