User talk:John M. Evjen
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Thermal Runaway - Lithium Ion Rechargeable batteries
[edit]Thermal Runaway is described in the Lithium Ion article as if it were a completely chemical process. In the case of the Lithium Ion batteries in Boeing aircraft, I do not believe that to be true. The reactions that are shown are certainly present, but the positive feedback which causes thermal runaway to proceed to destruction is the presence of a charging voltage (current) being applied to the battery. When that charging voltage (current) is independent of the thermal result of the heating process taking place in the battery, thermal runaway is made possible. The heating resulting from the chemical process causes a reduction of the Electro-chemical voltage ("back voltage") of the cells (battery). This results in an increase in charging current resulting in further increase in the chemical reaction. That is the true feedback element that causes thermal runaway. The diagram should therefor show the presence of this electrical current.