
Page | 001 Lithium Ion Battery Fire and Explosion QINGSONG WANG, JINHUA SUN, and GUANQUAN CHU State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230026, P.R. China ABSTRACT With the extensive applications of lithium ion batteries, many batteries fire and explosion accidents were reported. Base on the combustion triangle theory, the combustion triangle contributions of lithium ion battery were analysed. By using C80 micro calorimeter, the thermal behavior studies on the materials show that the flammable electrolyte, oxygen generated by charged cathode and anode decomposition, and exothermic reaction heats form the combustion triangle together. The thermal runaway of working materials in lithium ion battery system was studied with common used battery materials, and the no return temperature TNR was calculated is 75oC and the self-accelerating decomposition temperature (SADT) is 66.5oC. Further analysis shows that the lithium ion battery reaction chain according with Domino effect, therefore, the lithium ion battery fire and explosion developing sequences was drawn by Domino chain. The Domino chain explains the fire and explosion developing process perfectively, and then the countermeasures can be taken by breaking the Domino chain for the safety of lithium ion battery. KEYWORDS: lithium ion battery, explosion, fire, combustion triangle, thermal runaway, domino effect INTRODUCTION In 1991, Sony commercialized the Lithium ion battery and it is extensively used in many fields at present [1], such as many kinds of portable electronic equipments and electric vehicle or hybrid electric vehicle. When lithium ion batteries replaced nickel metal hydride, researchers increased the energy density, eliminated the memory effect, and made batteries lighter. But despite those merits gain, there is one big drawback: lithium ion batteries are flammable. Lithium ion batteries in most cases use cobalt oxide, which has a tendency to undergo "thermal runaway". When the material is heated up, it can reach an onset temperature that begins to self-heat and progresses into fire and explosion. The organic electrolytes in many lithium ion batteries are highly flammable when heated. A bulletin from Island Tel of Prince Edward Island reported two cases of Cellular Phone Batteries being shorted out and causing a fire hazard. It also was reported that two researchers were hurt by lithium ion battery explosion in November 11, 2004 Shanghai, as well as many cases were reported before. The safety problem of lithium ion batteries have become one key handicap in theirs popularization, many researches have been carried out in the thermal decomposition of electrolyte, anode and cathode [2-4]. However, the fire and explosion theory of lithium ion battery is few reported and needed further studies to ensure the safe use of lithium ion batteries. FIRE SAFETY SCIENCE–PROCEEDINGS OF THE EIGHTH INTERNATIONAL SYMPOSIUM, pp. 375-382 COPYRIGHT © 2005 INTERNATIONAL ASSOCIATION FOR FIRE SAFETY SCIENCE 375
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