There are provided novel methods of fabricating batteries, particularly rechargeable lithium ion batteries comprising a microporous polymeric gel layer on one or more electrodes of the batteries. The methods include laminating a gellable polymer film to at least one electrode and forming a microporous gellable polymer layer from the laminated film on the electrode. The microporous gellable polymer layer can be produced by extracting plasticizer from the polymer with a solvent. The polymeric gel on the electrode can be formed by exposing the microporous gellable polymer layer to an electrolyte solution which includes a lithium salt.