The carbon negative electrode produces an exothermic reaction at about 100 °C–140 °C. Although it releases less heat than that from the positive electrode, it could still make the temperature of the battery reach 220 °C. In the meantime, oxygen would be released from the lithium metal oxide, resulting in TR of the battery.
Lithium metal oxide in the positive electrode could be the most dangerous component, and it exotherms more than 500 J/g above 200 °C. The carbon negative electrode produces an exothermic reaction at about 100 °C–140 °C.
Therefore, improving the thermal stability of SEI is also an appropriate way to improve the safety of negative electrode. Mild oxidation, deposition of metals and metal oxides, coating of polymers and other types of carbon modification methods have enhanced the surface structure of the graphite anode [ 93 ].
The development of large-capacity or high-voltage positive-electrode materials has attracted significant research attention; however, their use in commercial lithium-ion batteries remains a challenge from the viewpoint of cycle life, safety, and cost.
Very often, it comes directly from the name of the positive electrode active material. To compare these options, the characteristics used in the previous figure are generally used (specific power, specific energy, cost, life, safety). For the battery life, two main characteristics are to be considered : Cycle life: aging in use.
In the first place, the effects of carbon materials as electrodes on battery safety performance and electrochemical properties were summarized. Subsequently, the roles of each component during TR and the process were introduced, the importance of carbon materials was highlighted.