An active material comprises a core particle containing LiCo(1-x)MxO2 and/or Li(Mn(1-y)My)2O4, and a coating part covering at least part of a surface of the core particle, while the coating part contains LiVOPO4. Here, M is at least one element selected from the group consisting of Al, Mg, and transition elements, 0.95>=x>=0, 0.2>=y>=0, and V in LiVOPO4 may partly be substituted by at least one element selected from the group consisting of Ti, Ni, Co, Mn, Fe, Zr, Cu, Zn, and Yb. The invention also relates to an electrode using the above active material (5) and a battery using the electrode. Moreover the invention also relates to a method for manufacturing the active material (5).