Technology and economic analysis of second-life batteries as stationary energy storage: A review

With global warming on the rise, the push for zero emission transportation continues to grow. The transportation sector's solution to these increasing concerns introduced society to electric vehicles (EVs) as a replacement for traditional internal combustion engine (ICE) vehicles. Although the objective of EVs seems obvious, the problem is more complex than it seems. EVs come with an undeniable problem, battery decommission and disposal. However, this possibly offers a unique opportunity if research continues in its current direction. An exclusive characteristic to EV batteries is their requirement to deliver power in such a way that the vehicle can accelerate quickly and drive extended distances. These demanding applications mean the battery has to be at a sufficient state of health (SOH) to deliver satisfactory results. Once a battery's SOH reduces to a level that is no longer adequate, it must be retired from the EV. The EV population has grown significantly and is forecasted to continue growing exponentially, thus coming with the accumulation of retired batteries. Serious concerns are drawn to the handling of such batteries. However, research shows that there is promising repurposing that can give retired EV batteries a second life, referring to them as second life batteries (SLBs). Research in this area is ongoing to realize concerns about performance and cost compared to using new batteries in various applications, under a variety of conditions. This review paper outlines these topics, providing an brief, overall comparison of SLBs to new batteries.