Electrochemical accumulators possess several desirable features, including pollution-free operation, high round-trip efficiency, flexible power and energy characteristics to meet different grid functions, compact size and long cycle life. Among all the possible types of electrochemical accumulators, this work focuses on lithium-ion accumulators, as they have a vast operating range and are of great importance, especially for the new sustainable mobility trend, which requires high-efficient batteries for electric automobility. All in all, security issues with these devices are yet to be faced due to occasional accidents and explosions, and the development of new, safer constituent materials is a key point of their future.