Abstract: Disclosed herein is a high thermal resistant polyolefin-based separator including a coating layer containing polyamic acid. Specifically, the separator includes a polyolefin-based substrate film, and a coating layer containing polyamic acid formed on one or both surfaces of the polyolefin-based substrate film, wherein the polyamic acid contains one or more functional groups selected from the group consisting of a sulfone group, a trifluoromethyl group, an alkyl group, and a phenyl ether group. Also, disclosed herein is an electrochemical battery having improved thermal stability by using the separator including a coating layer containing polyamic acid.

Abstract: Methods for preparing a silicon-based electroactive material for use in an electrochemical cell are provided. The methods include heating a silicon oxide (SiOx, where 0.1?x?2) particle to a temperature between about 600° C. and about 1200° C. over a period between about 30 minutes and about 10 hours to form the silicon-based electroactive material, where the silicon-based electroactive material includes a silicon oxide matrix and a plurality of silicon crystallites embedded therein. In certain instances, the heating may occur in an inert atmosphere such that the silicon crystallites are distributed throughout the silicon oxide matrix. In other instances, the heating may occur in a reducing environment such that the silicon crystallites are condensed in one or more regions in the silicon oxide matrix. In each instance, the silicon-based electroactive material may be carbon coated by heating the silicon-based electroactive material in an environment including hydrocarbons.

Abstract: Disclosed herein is a high thermal resistant polyolefin-based separator including a coating layer containing polyamic acid. Specifically, the separator includes a polyolefin-based substrate film, and a coating layer containing polyamic acid formed on one or both surfaces of the polyolefin-based substrate film, wherein the polyamic acid contains one or more functional groups selected from the group consisting of a sulfone group, a trifluoromethyl group, an alkyl group, and a phenyl ether group. Also, disclosed herein is an electrochemical battery having improved thermal stability by using the separator including a coating layer containing polyamic acid.

Abstract: The present invention relates to: a separator comprising a porous substrate, and a heat resistant porous layer on one or both surfaces of the porous substrate, wherein the heat resistant porous layer comprises a cross-linked product of a cross-linkable functional group-containing phosphate-based or phosphonate-based monomer, oligomer, or polymer; an electrochemical cell comprising the same; or a method for preparing the separator.

Abstract: Disclosed herein is a high thermal resistant polyolefin-based separator including a coating layer containing polyamic acid. Specifically, the separator includes a polyolefin-based substrate film, and a coating layer containing polyamic acid formed on one or both surfaces of the polyolefin-based substrate film, wherein the polyamic acid contains one or more functional groups selected from the group consisting of a sulfone group, a trifluoromethyl group, an alkyl group, and a phenyl ether group. Also, disclosed herein is an electrochemical battery having improved thermal stability by using the separator including a coating layer containing polyamic acid.