Totally-closed immersed liquid cooling device and manufacturing method

The invention provides a totally-closed immersed liquid cooling device and a manufacturing method. The totally-closed immersed liquid cooling device comprises a totally-closed trough body, the interior of the totally-closed trough body is hollowed out, an opening is formed in the top of the totally-closed trough body, a heat conductor is fixed to the opening of the top of the totally-closed troughbody, a condenser is connected to the lower part of the heat conductor, a cooling device is connected to the upper part of the heat conductor, an operation mainboard is fixed to the bottom of the totally-closed trough body, the totally-closed trough body contains cooling liquid, and the cooling liquid submerges the operation mainboard; a power connector is arranged on the totally-closed trough body, and the power connector is correspondingly connected with the operation mainboard and an external power supply; and the arrangement height of the power connector is higher than the top surface height of the cooling liquid