Improved Safety in Large Format Lithium-Ion Cells and Batteries

Yardney Technical Products (YTP) has put together a team of industry experts to address the safety of large format, high energy density Li-ion cells and batteries. YTP will utilize Exponent, Inc and their extensive experience in battery failure analysis and Celgard, Inc and their comprehensive electrode level thermal modeling capability. The effort begins with YTP building cells to evaluate a range of cathode materials (Spinels, Layered, and Olivines) in high energy cell chemistries for both available energy and reactivity in failure modes. YTP will also evaluate the practicality of hybrid separator systems in which the separator and/or electrodes are coated with a thin electrically insulating, temperature impervious layer. These layers would leave a residual electrical insulator in place in the result of separator failure from an over temperature condition. This creates a strong barrier to propagation resulting from an internal electrical short. Finally, YTP will model various novel cell geometries that are designed to interrupt the propagation front of a failure event. In summary, Phase I will identify the safest cathodes and anode systems that can meet the energy requirements, evaluate a novel separator system and model or empirically test the ability of novel cell geometries to terminate event propagation.