This study presents a novel method for fabricating self-poled piezoelectric polymer composites through melt-state energy implantation. The approach enables the creation of polyvinylidene difluoride/barium titanate (PVDF/BTO) composites with a high piezoelectric coefficient (d33) of ~51.20 pC/N at a low density of ~0.64 g/cm³. The method involves applying dynamic pressure during fabrication, which induces structural changes in both PVDF and BTO, leading to self-poling. The resulting porous material serves as a highly sensitive pressure sensor with a high output of ~20.0 V and sensitivity of ~132.87 mV/kPa, and as a high-output mechanical energy harvester, achieving a power density of ~58.7 mW/m² under 10 N pressure with long-term durability. The study also demonstrates that the material can be used as a self-powered human motion sensor, with output voltages varying from -40 V to -90 V depending on the motion type. The method avoids the need for electrical poling, offering a sustainable and efficient way to fabricate piezoelectric materials. The results show that the proposed method achieves a high performance lightweight, flexible piezoelectric polymer composite, with a high d33 value of -51.20 pC/N, and a high figure of merit (FOM) and g33 value, outperforming other reported piezoelectric materials. The mechanism of energy implantation-induced self-poling is attributed to the formation of β-phase PVDF and the crystalline orientation and lattice expansion of BTO. The study highlights the potential of this method for fabricating high-performance piezoelectric materials and expanding their applications in flexible and lightweight devices.This study presents a novel method for fabricating self-poled piezoelectric polymer composites through melt-state energy implantation. The approach enables the creation of polyvinylidene difluoride/barium titanate (PVDF/BTO) composites with a high piezoelectric coefficient (d33) of ~51.20 pC/N at a low density of ~0.64 g/cm³. The method involves applying dynamic pressure during fabrication, which induces structural changes in both PVDF and BTO, leading to self-poling. The resulting porous material serves as a highly sensitive pressure sensor with a high output of ~20.0 V and sensitivity of ~132.87 mV/kPa, and as a high-output mechanical energy harvester, achieving a power density of ~58.7 mW/m² under 10 N pressure with long-term durability. The study also demonstrates that the material can be used as a self-powered human motion sensor, with output voltages varying from -40 V to -90 V depending on the motion type. The method avoids the need for electrical poling, offering a sustainable and efficient way to fabricate piezoelectric materials. The results show that the proposed method achieves a high performance lightweight, flexible piezoelectric polymer composite, with a high d33 value of -51.20 pC/N, and a high figure of merit (FOM) and g33 value, outperforming other reported piezoelectric materials. The mechanism of energy implantation-induced self-poling is attributed to the formation of β-phase PVDF and the crystalline orientation and lattice expansion of BTO. The study highlights the potential of this method for fabricating high-performance piezoelectric materials and expanding their applications in flexible and lightweight devices.