BATTERY SYSTEM

Disclosed is a battery system that is easy to install or expand and has improved safety. The battery system according to an aspect of the present disclosure includes a plurality of battery containers, each including a battery rack, a container housing accommodating the battery rack in an internal space, and a first power line configured to transmit charge power and discharge power, wherein the first power lines of the battery containers are connected to each other; and a control cabinet including a control module configured to control the plurality of battery containers, a cabinet housing accommodating the control module in an internal space, and a second power line configured to be connected to the first power line of one of the plurality of battery containers.