Current interrupter for electrochemical cells

摘要

A current interrupt assembly for electrochemical cells is disclosed. The current interrupter assembly may be a self-contained, sealed unit which may be separately inserted into the cell during cell construction. Several current interrupt assemblies may be inserted in the cell. The current interrupter assembly has particular utility for thin rechargeable cells and when inserted in the cell forms a portion of the electrical pathway between a cell electrode and corresponding terminal. The current interrupt mechanism comprises a thin thermally responsive member preferably comprising a disk of a shape memory metal alloy having a curved surface. When cell temperature exceeds a predetermined value the disk deflects to cause a break in the electrical pathway within the assembly. The assembly may include therein a flexible electrically conductive member which forms a part of the electrical pathway within the assembly and which is physically responsive to deflection of the thermally responsive member. The assembly may also include a pressure actuated diaphragm which may form a portion of the assembly housing. When the cell internal pressure exceeds a predetermined level the diaphragm deflects causing a break in the electrical pathway within the assembly, thereby shutting down the cell.