Battery rack, power storage device, and power generation system

A battery rack comprising:

• a plurality of battery modules;
• a plurality of rack cases stacked in upward and downward directions and accommodating the plurality of battery modules;
• an injection pipe on each of the plurality of rack cases, each injection pipe comprising:
• a main body portion including an inlet through which an extinguishing agent is injected and the main body portion extending along an arrangement of the plurality of battery modules;
• and
• a distributor extending toward each of the plurality of battery modules from the main body portion and including an outlet inserted into each of the plurality of battery modules;
• a flexible pipe to be bendable and comprising:
• a first coupler located at a first end of the flexible pipe to be connectable to a supply pipe for supplying the extinguishing agent;
• and
• a second coupler located at a second end of the flexible pipe to be connectable to the inlet of the injection pipe;
• and
• an intermediate pipe to connect between an injection pipe provided on a rack case located on a relatively upper portion and an injection pipe provided on a rack case located on a relatively lower portion, the rack cases being from among the plurality of rack cases, and to have a bendable form.