TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Component: The lithium ion conducting layer comprises a lithium ion conductor comprising a compound of formula Li1+yM2-yXz (1). The lithium is included in an amount of 1-1.6 mole%. The M is included in an amount of 1-2 mole%. The X is included in an amount of 2-3 mole%. The lithium ion conducting layer comprises a lithium ion conductor comprising a compound from lithium titanium aluminum phosphate (Li1.3Ti1.7Al0.3(PO4)3), and/or lithium titanium phosphate (LiTi2(PO4)3); and particles with a median particle diameter (d50) of 1-2000 nm. The lithium ion conducting layer is present in an amount of 0.1-10 wt.% based on the total weight of the active material.y= greater than or equal to 0 to less than or equal to 2;z= greater than or equal to 1 to less than or equal to 3;M=alkali metals, alkaline-earth metals, group 13 elements, group 14 elements, transition elements and/or rare earth elements, preferably Na, K, Mg, Ca, Sr, Ni, Co, Si, Ti, B, Al, Sn, Mn, Cr, Fe, V and/or Zr; andX=-(PO4), -(VO4), and/or -(NbO4).Preferred Property: The lithium ion conducting layer has a thickness of 1-1000 nm.    TECHNOLOGY FOCUS - POLYMERS - Preferred Component: The lithium ion conducting layer comprises a lithium ion conductive polymer having a functional group from -SO3H, -SO3N, -COOH, and/or -COON1. The lithium ion conductive polymer is polyalkylene oxides having a functional group from -SO3H, -SO3N1, -COOH and/or -COON1; (EO)i(PO)m(EO)i block copolymers of ethylene oxide (EO) and propylene oxide (PO) including the functional group; poly(etherester)s having the functional group, poly(ethercarbonate)s having the functional group; poly(ethersulfone)s having the functional group; polyvinylchlorides (PVC) having the functional group; acrylonitrile/butadiene/styrene (ABS) polymers having the functional group; acrylonitrile/styrene/acrylester (ASA) polymers having the functional group; mixtures of ASA polymers having the functional group, and alkylene carbonates having the functional group; styrene/acrylonitrile (SAN) copolymers having the functional group; methylmethacrylate/acrylonitrile/butadiene/styrene (MABS) copolymers having the functional group; polythiophenes having the functional group; polypyrrols having the functional group; polyanilines having the functional group; polyparaphenylenes having the functional group; and/or polyacenes having the functional group.N1=an alkali metal; andi, m=1-500. EXAMPLE - Lithium titanium aluminum phosphate (Li1.3Ti1.7Al0.3(PO4)3) (0.5 g) having a median particle diameter of 300 nm was dispersed into ethanol to prepare a composition for a lithium ion conductive layer. Then, lithium cobalt oxide (LiCoO2) (99.5 g) having an average particle diameter of 10 mu m was added to the composition, which was then agitated for 12 hours to surface-treat the LiCoO2. The surface-treated LiCoO2 was dried and heat-treated at 400 degrees C for 5 hours to prepare a positive active material including a lithium ion conductive layer, which included Li1.3Ti1.7Al0.3(PO4)3 on the surface of LiCoO2.