Positive electrode plate, secondary battery and power consuming device

A positive electrode plate, comprising a positive electrode current collector, a positive electrode film layer provided on at least one surface of the positive electrode current collector, and a conductive undercoat layer between the positive electrode current collector and the positive electrode film layer, wherein

• the positive electrode film layer comprises a positive electrode active material with a core-shell structure;
• the positive electrode active material comprises an inner core and a shell coating the inner core;
• the inner core includes Li1+xMn1−yAyP1−zRzO4, where x=−0.100 to 0.100, y=0.001 to 0.005, z=0.001 to 0.100, A is selected from one or more of Zn, Al, Na, K, Mg, Mo, W, Ti, V, Zr, Fe, Ni, Co, Ga, Sn, Sb, Nb and Ge, and R is selected from one or more of B, Si, N and S;
• the shell includes a first coating layer coating the inner core and a second coating layer coating the first coating layer, wherein
• the first coating layer includes pyrophosphate of MP2O7 and phosphate of XPO4, wherein M and X are each independently selected from one or more of Li, Fe, Ni, Mg, Co, Cu, Zn, Ti, Ag, Zr, Nb or Al;
• and
• the second coating layer includes carbon;
• and
• the conductive undercoat layer includes a first polymer, a first water-based binder, and a first conductive agent, wherein
• the first polymer comprises
• a first monomer unit represented by formula 1;
• a second monomer unit selected from at least one of a group consisting of a monomer unit represented by formula 2 and a monomer unit represented by formula 3;
• a third monomer unit selected from at least one of a group consisting of a monomer unit represented by formula 4 and a monomer unit represented by formula 5;
• and
• a fourth monomer unit represented by formula 6, in which R1, R2, and R3 each independently represent H, a carboxyl, an ester group, and groups of substituted or unsubstituted C1-C10 alkyl, C1-C10 alkoxy, C2-C10 alkenyl, and C6-C10 aryl, and R4 represents H, and groups of substituted or unsubstituted C1-C10 alkyl, C1-C10 alkoxy, C2-C10 alkenyl, and C6-C10 aryl;