Method for operating a battery system

A method for operating a battery system, which includes multiple strings connected to one another in parallel, each of the strings including at least one battery module in which multiple battery cells are interconnected in a series connection and/or in a parallel connection, the strings being switchable on and off from one another, and individual battery cells of the battery cells and/or individual battery cell packets which each include multiple battery cells of the battery cells interconnected in parallel, being switchable on and off from one another and being able to be bypassed, the method comprising the following steps:

• recognizing a fault of a battery cell of the battery system;
• switching off and bypassing the faulty battery cell and/or a faulty battery cell packet in which the faulty battery cell is located;
• switching off a faulty string which includes the faulty battery cell and/or the faulty battery cell packet;
• comparing a string voltage of the faulty string to a string voltage of intact strings of the strings in which no fault was recognized;
• and
• discharging the intact strings when voltage differences between the strings exceed a voltage threshold value.

A battery system which includes multiple strings connected to one another in parallel, each of the strings including at least one battery module in which multiple battery cells are interconnected in a series connection and/or in a parallel connection, the strings being switchable on and off from one another, and individual battery cells of the battery cells and/or individual battery cell packets which each include multiple battery cells of the battery cells interconnected in parallel, being switchable on and off from one another and being able to be bypassed, the battery system configured to:

• recognize a fault of a battery cell of the battery system;
• switch off and bypass the faulty battery cell and/or a faulty battery cell packet in which the faulty battery cell is located;
• switch off a faulty string which includes the faulty battery cell and/or the faulty battery cell packet;
• compare a string voltage of the faulty string to a string voltage of intact strings of the strings in which no fault was recognized;
• and
• discharge the intact strings when voltage differences between the strings exceed a voltage threshold value.

A vehicle, comprising:

• a battery system which includes multiple strings connected to one another in parallel, each of the strings including at least one battery module in which multiple battery cells are interconnected in a series connection and/or in a parallel connection, the strings being switchable on and off from one another, and individual battery cells of the battery cells and/or individual battery cell packets which each include multiple battery cells of the battery cells interconnected in parallel, being switchable on and off from one another and being able to be bypassed, the battery system configured to:
• recognize a fault of a battery cell of the battery system,
• switch off and bypass the faulty battery cell and/or a faulty battery cell packet in which the faulty battery cell is located,
• switch off a faulty string which includes the faulty battery cell and/or the faulty battery cell packet,
• compare a string voltage of the faulty string to a string voltage of intact strings of the strings in which no fault was recognized, and
• discharge the intact strings when voltage differences between the strings exceed a voltage threshold value.