Monitoring device for a battery, a lithium-ion battery, and method for the monitoring of a battery

A method for the monitoring of a battery (1) with a plurality of cell composites (2, 3, 4), which are connected by means of electrical cell couplers (20, 30, 40, 50), comprising a number of mutually parallel-connected battery cells (21, 22, 23;

• 31, 32, 33;
• 41, 42, 43), and temperature sensors (100, 200) arranged between the cell composites (2, 3, 4), wherein the voltage across each battery cell (21, 22, 23;
• 31, 32, 33;
• 41, 42, 43) in each cell composite (2, 3, 4) is measured,
• that the method comprising:
• measuring a voltage drop (Udrop) across at least one of the battery cells (21, 22, 23;
• 31, 32, 33;
• 41, 42, 43) on the electrical cell couplers (20, 30, 40, 50);
• measuring a temperature with at least one of the temperature sensors (100, 200);
• when the measured voltage drop exceeds a predetermined value, and simultaneously the measured temperature exceeds a predetermined temperature, generating a fault signal by the association of the two defective values;
• and
• in response to the fault signal, isolating the affected battery cell(s) from the cell composite (2, 3, 4).