Patent ID: 8278869

Claim:
A battery system, comprising: a plurality of battery packs; a plurality of terminal blocks to which the plurality of battery packs are connected; and a control circuit for controlling an operation of the battery packs connected to the terminal blocks, wherein each battery pack includes a first battery power supply terminal, a second battery power supply terminal, and a battery ID terminal, wherein a power supply voltage having a predetermined voltage is applied between the first battery power supply terminal and the second battery power supply terminal, wherein the battery ID terminal divides the power supply voltage into a first voltage to be applied between the first battery power supply terminal and the battery ID terminal, and a second voltage to be applied between the second battery power supply terminal and the battery ID terminal, when the battery pack is connected to one of the terminal blocks, wherein a voltage dividing ratio expressed as a ratio of the first voltage with respect to the power supply voltage or a ratio of the second voltage with respect to the power supply voltage is made to be different among the plurality of battery packs depending on the terminal blocks, such that the control circuit determines the terminal blocks to which the battery packs are connected by detecting the voltage dividing ratio.