Power supply device for server

A power supply device that supplies power to a plurality of servers, the power supply device comprising:

• a power distribution unit (PDU) electronically connected to an external alternating current (AC) power source;
• a plurality of power supply units (PSU) corresponding to the plurality of servers, each PSU connecting the PDU to a corresponding server, converting alternating current from the PDU into direct current (DC) and providing the direct current to the corresponding server;
• and
• a stand-by power source electronically connected to the plurality of PSUs, the stand-by power source comprising a plurality of storage units corresponding to the plurality of servers, each storage unit comprising a battery and a switch;
• the battery is electronically connected between a corresponding PSU and the switch, the switch is electronically connected to the PDU and the corresponding server;
• wherein each storage unit is located between two adjacent servers;
• each PSU charges a corresponding battery;
• if the external AC power source stops providing AC power to the PDU, the PDU sends a control signal to close the switch to allow the battery to supply DC power to the corresponding server.