Considering　the　large　demand　for　electricity　in　the　era　of　artificial　intelligence　and　big　data,　there　is　an　urgent　need　to　explore　novel　energy　storage　media　with　higher　energy　density　and　intelligent　temperature　self-check　functions.　High-entropy　(HE)　ceramic　capacitors　are　of　great　significance　because　of　their　excellent　energy　storage　efficiency　and　high　power　density　(PD).　However,　the　contradiction　between　configurational　entropy　and　polarization　in　traditional　HE　systems　greatly　restrains　the　increase　in　energy　storage　density.　Herein,　the　contradiction　is　effectively　solved　by　regulating　the　octahedral　tilt　and　cationic　displacement　in　ABO3-type　perovskite　HE　ceramics,　i.e.,　(1-x)[0.6(Bi0.47Na0.47Yb0.03Tm0.01)TiO3-0.4(Ba0.5Sr0.5)TiO3]-xSr(Zr0.5Hf0.5)O3　(BNYTT-BST-xSZH).　Combining　the　tape-casting　process　and　cold　isostatic　pressing,　the　optimal　BNYTT-BST-0.06SZH　ceramic　displays　a　large　recoverable　energy　storage　density　(10.46　J　cm-3)　at　685　kV　cm-1　and　a　high　PD　(332.88　MW　cm-3).　More　importantly,　due　to　Tm/Yb　codoping,　abnormal　fluorescent　negative　thermal　expansion　and　excellent　real-time　temperature　sensing　are　developed,　thus　the　application　of　fault　detection　and　warning　in　high-voltage　transmission　line　systems　is　conceptualized.　This　study　provides　an　effective　strategy　for　enhancing　the　polarization　of　energy-storing　HE　ceramics　and　offers　a　promising　material　for　overcoming　the　problems　of　insufficient　capacitor　density　and　thermal　runaway　in　terminal　communication.　Herein,　octahedral　tilt　and　cationic　displacement　are　observed　in　high　entropy　(HE)　BNT-　based　ceramics.　On　the　basis　of　tape-casting　process　and　cold　isostatic　pressing,　the　optimal　ceramics　display　a　large　Wrec　(10.46　J　cm-3)　at　685　kV　cm-1　and　a　high　power　density　(332.88　MW　cm-3).　Importantly,　Tm/Yb　codoping　endows　the　ceramics　with　fluorescent　temperature　self-check　feature.　image