NOVELTY - A stacked structure polymer film solar battery comprises a middle electrode comprising an electron emitting layer made of n-type metal oxide including titanium oxide, zinc oxide and/or tin oxide, a metal layer made of aluminum, silver and/or gold metal and a cavity emitting layer made of p-type metal oxide including molybdenum oxide and/or tungsten oxide.    USE - A stacked structure polymer film solar battery.    ADVANTAGE - The composite middle electrode structure can be used in stacked components using conjugated polymer material with different light-absorption ranges as active layer to match the light-absorption of the entire battery to improve energy conversion rate.    DETAILED DESCRIPTION - A stacked structure polymer film solar battery comprises    (A) glass or plastic substrate;    (B) anode layer made of indium tin oxide with thickness of 180 nm;    (C) an anode modification layer made of a mixture of 3,4-ethylenedioxythiophene and polystyrenesulfonate in a weight ratio of 1:6 and having a thickness of 20-100 nm;    (D) an active layer comprising mixture of 40-80% conjugated macromolecule material poly(3-hexylthiophene) (P3HT) as electron donor and fullerene derivative (6,6)-2-phenyl 61C-2-butyric acid methyl ester (PCBM) as electron acceptor and having thickness of 50-150 nm;    (E) an active layer comprising a mixture of P3HT as electron donor and 40-80% PCBM as electron acceptor and having a thickness of 50-150 nm;    (F) cathode modification layer made of lithium fluoride (LiF), cesium fluoride (CsF) and/or calcium oxide (CaO) and having a thickness of 1-3 nm;    (G) a cathode layer made of aluminum, silver and/or calcium metal and having a thickness of 60-200 nm;    (H) electron emitting layer made of n-type metal oxide including titanium oxide (TiOx), zinc oxide (ZnO) and/or tin oxide (SnO2) and having a thickness of 10-50 nm;    (I) metal layer made of aluminum, silver and/or gold metal and having thickness of 10-50 nm; and    (J) cavity emitting layer made of p-type metal oxide including molybdenum oxide (MoO3) and/or tungsten oxide (WO3) and having thickness of 5-20 nm, where the electron emitting layer, metal layer and cavity emitting layer form the middle electrode of the polymer stacked solar battery.