SEPARATOR, PREPARATION METHOD THEREOF, SECONDARY BATTERY, AND ELECTRIC APPARATUS

Embodiments of the present application provide a separator, a preparation method thereof, a secondary battery, and an electric apparatus. The separator includes a first base film, a coating, and a second base film, where the coating is disposed between the first base film and the second base film, the coating includes an ion-trapping agent, and a reduction potential of the ion-trapping agent relative to lithium metal is 0 V to 2 V. A secondary battery containing the separator exhibits improved cycling performance.