To analyze the effect of fire in electric-vehicle battery on concrete cement structure. A scenario evaluation was conducted for fire occurrence due to external influences on lithium battery cells used in electric vehicles. Visual inspection was conducted at each stage of the battery fire, and the fire duration and temperature were measured. The battery temperature rise curve and temperature during fire have been examined previously. The stability of a cement structure was evaluated via X-ray diffraction and SEM analyses of the reaction-product changes with respect to temperature. The battery temperature rise curve shows that the battery begins to change at 200 °C–300 °C. However, the general stage of battery damage cannot be readily confirmed from the literature. The current experiment and literature review indicate that battery fire can cause the fire temperature to increase beyond 1000 °C within a few seconds. The reaction product changes structurally in cement from 300 °C or higher. Many voids are generated owing to the decomposition of Ca(OH)2 and C-S-H gel. The temperature of an electric-vehicle fire increases rapidly to 1000 °C or higher within a few seconds. High temperatures change the reaction products in cement structures, thus creating internal voids and cracks and reducing the stability of the structure; therefore, the appropriate countermeasures must be identified.

This study analyzed ignition probability about Lithium-polymer batteries of what variously were being produced wearable devices recently. The study analyzed ignition probability by PCM(Protection Circuit Module) operating state and overcharged, over-discharged, exposed to high temperatures of Lithium polymer batteries, analyzing wearable devices on the market. Then it classified experimental results to implement analysis comparison about weight, X-ray imaging, battery decomposition. With these experiments, the study analyzed combustion-possibility and fire patterns. These statistics will be used to measure and verify the cause of a fire when identify wearable devices using Lithium-polymer batteries.