| abstract |
Provided is a separator that reduces the deposit of metal ions on the surface of a negative electrode and provides a non-aqueous lithium secondary battery with little deterioration in capacity even after repeated charge and discharge at high temperatures. Furthermore, this invention provides the lithium ion secondary battery which uses such a separator, and its manufacturing method. According to the present invention, there is provided a battery separator comprising a cross-linked polymer layer having an iminodiacetic acid group in the side chain of a polymer molecular chain between a pair of porous resin films. Preferably, the cross-linked polymer layer is a substantially non-porous ion conductive layer, and the cross-linked polymer has an oxetanyl group having cationic polymerizability in a molecule. [Selection figure] None |