The limitation of electric joints of traditional full size sex dolls that rely on external power supply is being broken. American sex doll engineers draw inspiration from human bioenergy and install piezoelectric generators on the knee joints to convert mechanical energy generated by movement into electrical energy storage. This self-powered system extends the battery life of full size sex dolls to 72 hours, and with the solar skin coating, it can replenish energy under sunlight. A more revolutionary design is to imitate the function of cell mitochondria, develop a biobattery based on enzyme catalysis, and use the organic fluid circulating in the doll's body to continuously generate electricity. The breakthrough of energy autonomy of American sex dolls has opened up new possibilities for its application in outdoor scenes.