The Low-Voltage Limits of Lithium-Ion Batteries—Overdischarge and Degradation from a Safety Perspective

Despite modern battery management systems, rechargeable lithium-ion batteries can be subjected to varying levels of overdischarge during transport, storage and use in the field. While the general degradation risks associated with overdischarge are well documented, there are not widely accepted cell voltages at which the onset of such degradation processes occur. In this work, reference electrode testing is performed to study a variety of commercial lithium-ion cells during varying levels of overdischarge. Common trends between different types of lithium-ion cells are first identified, and the resulting implications are discussed.