Organic chemical fire suppressant for a battery pack

A fire extinguisher comprising:

• a pressure vessel;
• an organic compound inside the vessel, wherein the organic compound is 1,1,1,2,2,4,4,5,5,5-nonafluoro-4-(trifluoromethyl)-3-pentanone;
• carbon dioxide pressurized as a liquid inside the vessel;
• and
• an inert gas pressurizing the vessel;
• wherein a ratio of a mass of the organic compound to a mass of the carbon dioxide is between 1:4 and 4:1.

A method of cooling a battery cell in a battery pack, the method comprising:

• releasing a fire suppressant out of a pressure vessel in response to a detected fire event, wherein the fire suppressant is a mixture of an organic compound and carbon dioxide, and wherein the carbon dioxide is a liquid when pressurized inside of the pressure vessel;
• cooling the organic compound with the carbon dioxide by depressurizing and vaporizing the carbon dioxide;
• flowing the fire suppressant into and throughout a battery pack containing the battery cell;
• cooling the battery cell with the fire suppressant, wherein the organic compound evaporates to cool the overheating battery cell;
• and
• removing evaporated organic compound and evaporated carbon dioxide from the battery pack.