Thermal study of organic electrolytes with fully charged cathodic materials of lithium-ion batteries

We systematically investigated thermal effects of organic electrolytes/organic solvents with fully charged cathodic materials (Li0.5CoO2) of Li-ion battery under rupture conditions by using oxygen bomb calorimeter. In the six studied systems, both the amount of combustion heat and heat release rates showed a pronounced increase with the increase in mass ratios of cathodic materials to electrolytes/solvents. More importantly, synergistic effects not simply physical mixtures have firstly been observed between cathodic materials and electrolytes/solvents in the complete combustion reactions. The results have been further analyzed by X-ray diffraction spectra, which revealed that Co3O4, CoO, and LiCoO2 were the main solid products for the combustion reactions of studied systems. And there are more CoO and less LiCoO2 products for the higher ratio of cathodic materials system and more amount of heat generated. It means that the combustion reaction, which produced CoO, generated more amount of heat than LiCoO2.