Thermal runaway prevention

A battery assembly comprising:

• a first battery comprising a first terminal;
• a second battery comprising a second terminal;
• a conductive connector comprising a first end and a second end, wherein the conductive connector electrically connects the first terminal to the second terminal;
• a spring mechanically coupled to the conductive connector;
• and
• a sacrificial block, distinct from the electrical connector, disposed on a surface of the conductive connector, wherein the sacrificial block forces the spring into an energy-storing configuration, wherein, when the spring is forced into the energy-storing configuration, the first end of the conductive connector is electrically and physically coupled to the first terminal and the second end of the conductive connector is electrically and physically coupled to the second terminal;
• wherein the sacrificial block is configured to melt when a battery assembly temperature exceeds a threshold temperature value such that, when the sacrificial block melts, the spring relaxes from the energy-storing configuration and mechanically displaces the conductive connector to break the electrical and physical coupling between the first end of the conductive connector and the first terminal and to break the electrical and physical coupling between the second end of the conductive connector and the second terminal.