The invention discloses a high-efficiency power generation device by utilizing automobile
tail gas. The device mainly comprises an air suction
pipe, a
spark plug, a device for preparing
carbon dioxide by
tail gas, a motion cylinder, a sliding body, a spring, a
crank link mechanism, a power generator, a thermoelectric power generation sheet, a
tail gas gathering chamber, a
liquid carbon dioxide
cooling chamber and the like. According to the invention, the flow rate of the high-temperature tail gas at the position of a horn at the connecting end of an
exhaust pipe and the motion cylinder is accelerated, and negative pressure is caused, thus the air suction
pipe sucks
fresh air, a
mixed gas is formed, and enters the motion cylinder; the
spark plug is ignited continuously for secondary
combustion, high-temperature and high-pressure tail gas is generated, the sliding body is pushed to move forward, and simultaneously, after the high-temperature tail gas generated by the secondary
combustion enters the tail gas gathering chamber through small holes at the bottom of the motion cylinder, pressure is reduced, the power generator is driven by a
crank shaft and a
crank link mechanism to generate
electricity through the reciprocating pulling effect which is formed by the reversal motion of the sliding body by the spring, at the same time,
electric power is generated through
temperature sensing of the
temperature difference of the tail gas gathering cavity and the
liquid carbon dioxide cooling cavity by utilizing the thermoelectric power generation sheet, and the
electricity energy is stored in an automobile battery.