Method for making lithium foil anode of all-solid-state lithium battery

A method for making a lithium foil anode of an all-solid-state lithium battery consisting of the lithium foil anode, a cathode, and a composite polymer electrolyte membrane, the method comprising the steps of:

• a) dispersing a carbon nanomaterial in water to form a dispersion;
• b) mixing dopamine with the dispersion so as to permit the dopamine to perform a polymerization reaction in the dispersion to obtain a surface-modified carbon nanomaterial which is surface-modified by polydopamine;
• c) forming a regular sub-millimeter scale textured structure on a lithium foil;
• d) mixing the surface-modified carbon nanomaterial with a lithium ion-containing polymer to form a mixture;
• and
• e) applying the mixture on the lithium foil;
• wherein step c) is performed by cold pressing the lithium foil with a metal mesh having a textured pattern for forming the regular sub-millimeter scale textured structure,
• wherein in step c), the regular sub-millimeter scale textured structure includes
• a plurality of columns of first depressions formed on a surface of the lithium foil, the columns of the first depressions being displaced from each other in a first direction, each of the columns of the first depressions including a plurality of the first depressions which are displaced from each other in a second direction transverse to the first direction, the first depressions of each of the columns of the first depressions being staggered with the first depressions of an adjacent one of the columns of the first depressions;
• and
• a plurality of rows of second depressions formed on the surface of the lithium foil, the rows of the second depressions being displaced from each other in the second direction, each of the rows of the second depressions including a plurality of the second depressions which are displaced from each other in the first direction, the second depressions of each of the rows of the second depressions being staggered with the second depressions of an adjacent one of the rows of the second depressions such that one of the first depressions is surrounded by four of the second depressions and one of the second depressions is surrounded by four of the first depressions, and
• wherein each of the first and second depressions is configured as a spindle-like shape having a length ranging from 450 μm to 650 μm, and
• wherein a source of a lithium ion of the lithium ion-containing polymer is selected from lithium hydroxide, lithium nitrate, lithium acetate, lithium chloride, lithium hydrogen phosphate, lithium phosphate, lithium carbonate, or combinations thereof.