Automatic diagnostic system for second use lithium ion battery for stationary energy storage applications

Energy storage has several beneficial applications in high power electrical systems, however, the costs of new batteries impede large scale deployment. Second use lithium ion batteries have been proven to be technically feasible for energy storage in the grid while being much cheaper than new batteries. This paper presents the design, construction and testing of an automatic test bench for second use lithium ion batteries for stationary energy applications. This automatic test bench cycles a battery while simulating real life conditions, this way it is possible to perform an accelerated life cycle test. The testing of the battery is monitored by the device and the information is stored to further understand the batterie's behavior and determine its viability for stationary energy storage applications. The device gathers data via an array temperature, voltage and current sensors. The battery tested by the system is a lithium ion battery built from heterogeneous second use lithium ion cells recovered form discarded laptop batteries. The results from the device show that the battery has potential for stationary energy storage applications, however, more data is needed to have a better understanding of the evolution of the battery over time. Also, some improvements to the device are mentioned as future work.