Articles ＆ files | Energies | Energy efficiency | Energy storage | Electric vehicles
Batteries are a key enabling technology for clean transportation. One of the major trends shaping the booming battery market is costs. As battery costs continue to come down, they will gradually address the grid's backup power needs. Liten's battery research addresses both sides of the equation, with advances that are boosting energy and power densities and, as result, performance. Safety is also an integral part of Liten's battery research. The institute is constantly striving to improve its knowledge of the factors that influence battery safety during operation and battery lifespans, two issues that have a direct impact on the long-term viability of the industry.
To increase performance, Liten researchers are developing new chemistries and investigating new battery packs and systems for different use cases.
In terms of chemistry, the future generations of batteries currently on the drawing board leverage solvent-free electrode fabrication processes and integrate hybrid and solid electrolytes combined with metal lithium negative electrodes. And, as Liten researchers work to control metal lithium, they are also intensively investigating NMC, Ni-rich, and Li-rich lamellar oxides, rock-salt-type materials for the positive electrode, and silicon-based composites for the negative electrode.
In addition to lithium batteries, and to meet the needs of specific applications, Liten is exploring several alternative technologies: These include hybrid potassium superconductors, Na-ion batteries, organic materials for redox flow batteries, and lithium-sulfur and magnesium-ion.
In terms of systems, the primary objective is to achieve optimal dimensioning for the target application. The dimensioning process is based on performance testing at the cell and pack scales and on Liten's deep knowledge of multi-physics, multiscale modeling.
Safety issues like thermal runaway and the propagation phenomena that sometimes occur as a result are also addressed, with the goal of making the best cell choices (chemistry, format, size). Safety can also be enhanced through mechanical and thermal integration supported by a BMS (Battery Management System).
A pedagogical and practical report has recently been published to inform stakeholders of the risks and solutions. It provides a summary of four years work carried out by a group of civil and fire safety experts, scientists and industrialists, which was specifically created on the initiative of the French Directorate General for Civil Security and Crisis Management and the Fire Department of Savoie-France (SDIS73).
A new composite packaging with flexible sensors ensures continuous increased safety while shaving 15% off battery pack weight. The system, which has potential for a wide range of other uses, leverages structural electronics, battery, and signal processing research.
As the number of IoT devices increases, so does the number of spent batteries that have to be dealt with. Making battery lifespans longer is one of the responses to this major environmental and societal challenge. The CEA Tech institutes are developing technologies and contributing to research and development projects to do just that.
Transportation and Mobility
CEA is a French government-funded technological research organisation in four main areas: low-carbon energies, defense and security, information technologies and health technologies. A prominent player in the European Research Area, it is involved in setting up collaborative projects with many partners around the world.