An overcurrent protection device for a circuit to be monitored, having at least one trigger unit, which is configured for an interruption of the circuit in at least one trigger situation and which includes at least one conductor section which is configured for a conduction of a current to be monitored, at least one conductive trigger element, which includes at least one thermo magnetically-shiftable material configured for a magnetic property change in dependence on the temperature induced by a current that flows through the conductor section, a conductive magnetic module, a conductive magnetic core, the conductive magnetic module being movable between a first position faced against the conductive trigger element permitting the conduction of the current through the conductor section and a second position faced against said conductive magnetic core breaking the conduction of the current through the conductor section.

A battery system includes a first electrical interface and safety switch connected to the first electrical interface and including a shape memory alloy element configured to deform from an unactuated configuration to an actuated configuration in response to reaching an activation temperature. A second electrical interface is connected to the safety switch, and the connection between the first electrical interface, the safety switch, and the second electrical interface enables electrical current to flow through a LIB cell. When the shape memory alloy element is the unactuated configuration, the safety switch directly engages the first electrical interface and the second electrical interface and enables electrical current to flow through the LIB cell. When in the actuated configuration, the safety switch disconnects from at least one of the first electrical interface and the second electrical interface and disables electrical current from flowing through the LIB cell.

A battery system includes a first electrical interface and safety switch connected to the first electrical interface and including a shape memory alloy element configured to deform from an unactuated configuration to an actuated configuration in response to reaching an activation temperature. A second electrical interface is connected to the safety switch, and the connection between the first electrical interface, the safety switch, and the second electrical interface enables electrical current to flow through a LIB cell. When the shape memory alloy element is the unactuated configuration, the safety switch directly engages the first electrical interface and the second electrical interface and enables electrical current to flow through the LIB cell. When in the actuated configuration, the safety switch disconnects from at least one of the first electrical interface and the second electrical interface and disables electrical current from flowing through the LIB cell.