Provided are a composite polymer electrolyte for a lithium secondary
battery in which a composite polymer matrix multi-layer structure
composed of a plurality of polymer matrices with different pore sizes is
impregnated with an electrolyte solution, and a method of manufacturing
the same. Among the polymer matrices, a microporous polymer matrix with a
smaller pore size contains a lithium cationic single-ion conducting
inorganic filler, thereby enhancing ionic conductivity, the distribution
uniformity of the impregnated electrolyte solution, and maintenance
characteristics. The microporous polymer matrix containing the lithium
cationic single-ion conducting inorganic filler is coated on a surface of
a porous polymer matrix to form the composite polymer matrix multi-layer
structure, which is then impregnated with the electrolyte solution, to
manufacture the composite polymer electrolyte. The composite polymer
electrolyte is used in a unit battery. The composite polymer matrix
structure can increase mechanical properties. The introduction of the
lithium cationic single-ion conducting inorganic filler can provide
excellent ionic conductivity and high rate discharge characteristics.