BATTERY SYSTEM

PROBLEM TO BE SOLVED: To provide a battery system which determines in a simple composition the wiring connection state of each battery cell of battery cells constituting a battery pack.SOLUTION: The battery system comprises: a first battery cell including a first electrode terminal of first polarity and a second electrode terminal of second polarity; a second battery cell including a third electrode terminal of first polarity and a fourth electrode terminal of second polarity; a first switch which can electrically connect a first and a second joint via a first resistive element; a second switch which can electrically connect a second and a third joint via a second resistive element; a first signal wiring which is electrically connected to the first electrode terminal through the first joint; a second signal wiring which is electrically connected to the second and the third electrode terminals through the second joint; third signal wiring which is electrically connected to the fourth electrode terminal through the third joint; and a control device.