How a liquid that acts like a solid could prevent plane fires

first_img By Randall HymanAug. 22, 2018 , 5:00 AM Recent car crashes and airline fires have made it abundantly clear: Lithium-ion batteries, which power most portable devices and electric vehicles, are dangerous. If crushed and twisted, the porous plastic membrane that separates the electrodes inside can instantly shred and cause a short circuit, igniting the battery’s highly flammable lithium electrolyte.Now, taking a page from children’s author Dr. Seuss, chemist Gabriel Veith and colleagues at Oak Ridge National Laboratory in Tennessee may have found a solution: oobleck. The liquid mixture of cornstarch and water (which gets its name from a classic American children’s book) acts like a solid if hit with sufficient force. While mixing up some oobleck for his children, Veith got an idea worthy of a cat in a hat with a vat: Replace the cornstarch with silica and mix it into the electrolyte of a lithium-ion battery to produce a variation that transforms from flammable fluid to inert solid when impacted. In chemical terms, it’s called a shear thickening fluid.The trick was finding the right kind of silica. Other labs had tried irregularly shaped and rod-shaped silica particles, but, as they described earlier this year in Applied Materials & Interfaces, Veith’s team turned to a decades-old technique called the Stöber process to produce perfectly round nanoparticles of silica—often used to deliver medicine inside human cells. Such round particles are able to organize themselves into stronger barriers—and they’re easier to produce, Veith says. “You don’t have to reinvent the battery processing line because it’s compatible with present manufacturing technology.” Country * Afghanistan Aland Islands Albania Algeria Andorra Angola Anguilla Antarctica Antigua and Barbuda Argentina Armenia Aruba Australia Austria Azerbaijan Bahamas Bahrain Bangladesh Barbados Belarus Belgium Belize Benin Bermuda Bhutan Bolivia, Plurinational State of Bonaire, Sint Eustatius and Saba Bosnia and Herzegovina Botswana Bouvet Island Brazil British Indian Ocean Territory Brunei Darussalam Bulgaria Burkina Faso Burundi Cambodia Cameroon Canada Cape Verde Cayman Islands Central African Republic Chad Chile China Christmas Island Cocos (Keeling) Islands Colombia Comoros Congo Congo, the Democratic Republic of the Cook Islands Costa Rica Cote d’Ivoire Croatia Cuba Curaçao Cyprus Czech Republic Denmark Djibouti Dominica Dominican Republic Ecuador Egypt El Salvador Equatorial Guinea Eritrea Estonia Ethiopia Falkland Islands (Malvinas) Faroe Islands Fiji Finland France French Guiana French Polynesia French Southern Territories Gabon Gambia Georgia Germany Ghana Gibraltar Greece Greenland Grenada Guadeloupe Guatemala Guernsey Guinea Guinea-Bissau Guyana Haiti Heard Island and McDonald Islands Holy See (Vatican City State) Honduras Hungary Iceland India Indonesia Iran, Islamic Republic of Iraq Ireland Isle of Man Israel Italy Jamaica Japan Jersey Jordan Kazakhstan Kenya Kiribati Korea, Democratic People’s Republic of Korea, Republic of Kuwait Kyrgyzstan Lao People’s Democratic Republic Latvia Lebanon Lesotho Liberia Libyan Arab Jamahiriya Liechtenstein Lithuania Luxembourg Macao Macedonia, the former Yugoslav Republic of Madagascar Malawi Malaysia Maldives Mali Malta Martinique Mauritania Mauritius Mayotte Mexico Moldova, Republic of Monaco Mongolia Montenegro Montserrat Morocco Mozambique Myanmar Namibia Nauru Nepal Netherlands New Caledonia New Zealand Nicaragua Niger Nigeria Niue Norfolk Island Norway Oman Pakistan Palestine Panama Papua New Guinea Paraguay Peru Philippines Pitcairn Poland Portugal Qatar Reunion Romania Russian Federation Rwanda Saint Barthélemy Saint Helena, Ascension and Tristan da Cunha Saint Kitts and Nevis Saint Lucia Saint Martin (French part) Saint Pierre and Miquelon Saint Vincent and the Grenadines Samoa San Marino Sao Tome and Principe Saudi Arabia Senegal Serbia Seychelles Sierra Leone Singapore Sint Maarten (Dutch part) Slovakia Slovenia Solomon Islands Somalia South Africa South Georgia and the South Sandwich Islands South Sudan Spain Sri Lanka Sudan Suriname Svalbard and Jan Mayen Swaziland Sweden Switzerland Syrian Arab Republic Taiwan Tajikistan Tanzania, United Republic of Thailand Timor-Leste Togo Tokelau Tonga Trinidad and Tobago Tunisia Turkey Turkmenistan Turks and Caicos Islands Tuvalu Uganda Ukraine United Arab Emirates United Kingdom United States Uruguay Uzbekistan Vanuatu Venezuela, Bolivarian Republic of Vietnam Virgin Islands, British Wallis and Futuna Western Sahara Yemen Zambia Zimbabwe Email But the new goo couldn’t be injected into a battery like a normal liquid electrolyte, because the mere act of squirting turned it solid. Veith’s team found a workaround by prepositioning the silica particles within the plastic separation membrane and then injecting the liquid electrolyte afterward. Not only did his “oobleck” turn solid when impacted, it was also easier to manufacture and stronger than previously tested varieties.Like all shear-thickening fluids, though, the Oak Ridge oobleck—patented under the name Safe Impact Resistant Electrolyte—turns back into a liquid a few seconds after impact and can still allow a fiery reaction between electrodes. Veith’s team is working on a version that turns into a brick and stays that way. He notes it could be used in military jackets that transform from wearable batteries to life-saving armor when struck by bullets. After regulatory review, the Oak Ridge team expects its technology will be implemented in batteries within a few years, starting with the least “risk averse” applications. Thing One and Thing Two would be proud. Click to view the privacy policy. Required fields are indicated by an asterisk (*) How a liquid that acts like a solid could prevent plane fires Joseph Kaczmarek/AP Photo Sign up for our daily newsletter Get more great content like this delivered right to you! Countrylast_img read more