Battery cell design for improved safety

A safety cell comprising:

• a cell housing (1);
• a lid assembly (3) comprising a shorting structure (7-1), the lid assembly (3) connected to the cell housing (1) via a vent (2) and an electrical isolator (7);
• an electrode assembly (5) housed within the cell housing (1), and comprising a first electrode separated from a second electrode by a separator, wherein:
• the first electrode is electrically connected to the cell housing (1);
• the second electrode is electrically connected to the shorting structure (7-1);
• the first electrode, the second electrode and the separator are wound together;
• and
• wherein the safety cell comprises a non-venting configuration and a venting configuration, wherein:
• the non-venting configuration is characterized by the vent (2) connecting the lid assembly (3) to the cell housing (1) such that the internal safety cell pressure is maintained at a pressure above atmospheric;
• and
• the venting configuration is characterized by the steps of:
• (A) the vent (2) releasing the cell housing (1) from the lid assembly (3) when a predetermined internal pressure within the safety cell is exceeded;
• (B) venting the internal pressure;
• (C) the venting of the internal pressure dislodging the lid assembly (3) such that the shorting structure (7-1) makes electrical contact with the cell housing (1), discharging the safety cell;
• and
• (D) the venting of the internal pressure at least partially unwinding the electrode assembly (5) such that the first electrode makes electrical contact with the lid assembly (3), discharging the safety cell.

A safety cell comprising:

• a cell housing (1);
• a lid assembly (3) connected to the cell housing (1) via a vent (2);
• an electrode assembly (5) housed within the cell housing (1), and comprising a first electrode separated from a second electrode by a separator, wherein:
• the first electrode, the second electrode and the separator are wound together;
• and
• the second electrode is electrically connected to the lid assembly (3);
• wherein the safety cell comprises a non-venting configuration and a venting configuration, wherein:
• the non-venting configuration is characterized by the vent (2) connecting the lid assembly (3) to the cell housing (1) such that the internal safety cell pressure is maintained at a pressure above atmospheric;
• and
• the venting configuration is characterized by the steps of:
• (A) the vent (2) releasing the cell housing (1) from the lid assembly (3) when a predetermined internal pressure within the safety cell is exceeded;
• (B) venting the internal pressure;
• and
• (C) the venting of the internal pressure at least partially unwinding the electrode assembly (5) such that the first electrode makes electrical contact with the second electrode and/or the lid assembly (3), discharging the safety cell.

A safety cell comprising:

• a cell housing (1) with a vent;
• a lid assembly (3) connected to the cell housing (1);
• an electrode assembly (5) housed within the cell housing (1), and comprising a first electrode separated from a second electrode by a separator, wherein:
• the first electrode, the second electrode and the separator are wound together;
• and
• the first electrode is electrically connected to the cell housing (1);
• wherein the safety cell comprises a non-venting configuration and a venting configuration, wherein:
• the non-venting configuration is characterized by the vent (2) in a closed configuration such that the internal safety cell pressure is maintained at a pressure above atmospheric;
• and
• the venting configuration is characterized by the steps of:
• (A) the vent (2) opening to vent the internal pressure when a predetermined internal pressure within the safety cell is exceeded;
• and
• (B) the venting of the internal pressure at least partially unwinding the electrode assembly (5) such that the second electrode makes electrical contact with the first electrode and/or the cell housing (1), discharging the safety cell.