Provided herein is a method for preparing a cathode electrode based on an aqueous slurry. The invention provides a cathode slurry comprising a cathode material especially high Ni ternary cathode material with improved water stability. The cathode material shows lower tendencies for pH change when applied in the aqueous slurry. The lower processing temperatures may avoid the undesirable decomposition of cathode material having high nickel and/or manganese content. In addition, the batteries having the electrodes prepared by the method disclosed herein show impressive energy retention. The capacity retention of the battery is not less than 60% of its initial capacity after 2 weeks of high temperature storage.