Page | 007 thus, increasing the severity of the off-site consequences. If one of the Domino events is moved from the chain, then the e fire and explosion can be avoided, so the relative countermeasures can be taken to move or avoid the occurrence of the chain event, e.g., in order to decrease the battery temperature, the good thermal conductive materials can be designed as battery shell. As to the energy and gas cumulation, a safety valve should be designed in the battery and can open automatically when the inner pressure exceed the certain level, by this way, to ensure the battery safety.
Fig. 6. Domino effect of lithium ion battery fire and explosion.
Crush, mutilate, nail penetrate or disassemble will damaged the battery fatally, the consequence is more dangerous. The above abuses are easy cause to the short circuit and then bring to the Domino effect, and furthermore, the flammable electrolyte exposed to air is dangerous hazard too.
CONCLUSIONS
Lithium ion batteries have a very high energy density and have wide applications. While the flammable, high energy and active material increase their dangers of fire and explosion. The fuel, oxygen and energy can exist in the battery system, which provide the necessary contributions to the combustion triangle, thus there is the possibility of fire and explosion. The Li0.5CoO2 positive electrode and Li0.86C6 negative electrode decompose with the temperature rising up, at 170oC and 74oC respectively. The reaction oxygen products and large mount of exothermic heat are contributed to the combustion triangle.
The charged lithium ion battery materials are reactive substance with high activity, based
on Semenov theory, the lithium ion battery materials will undergo the thermal runaway
process at elevated temperature, and the SADT is 66.5oC, and no return temperature TNR
is 75oC for the (−)C | LiPF − EC + DEC | LiCoO (+) battery. For larger lithium ion 62
batteries, both SADT and TNR should be lower.
In the thermal runaway process, a large mount of reaction occur and form the reaction chain till to fire and explosion, which illuminates the Domino effect. Then, measures can be taken to break the Domino chain to prevent the accident, such as safety valve.
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