Periodic Reporting for period 1 - iBEMS-SeLiBat (Integrated Battery and Energy Management System for Second-Life Battery energy storage)
Berichtszeitraum: 2022-12-01 bis 2023-08-31
This project improves the way battery energy storage systems (BESS) are operated by bringing together the BMS, which traditionally performs battery pack state estimation, and the EMS, which controls the (dis)charging of the BESS, into iBEMS, an integrated battery & energy management system.
The iBEMS has access to all raw battery cell measurements normally only accessible by the BMS. The energy management and optimisation function of the iBEMS is performed leveraging the plethora of useful data from the battery cells. Traditionally, an EMS only sees the state of charge of the battery pack and this data would have been lost. The data is available in Octave’s battery cloud, which opens multiple improvements in operating the BESS, such as delivering an optimized service, building a digital twin of the cells, applying machine learning, extending the lifetime, improving monitoring and enabling predictive maintenance, all which are of particular importance for second-life battery systems.
We have designed and build two different second-life Battery Energy Storage systems, using two different types of used Electric Vehicle (EV) battery modules, one 75kWh system with a 30kVA inverter and another one a 120kWh system with a 92kVA inverter. Both systems have been operational and running for several months, demonstrating multiple energy management applications and generating very granular data about the second-life battery cells. We are currently in the process of refining and optimising this design for easier assembly, quicker installation and safer maintenance.
We have setup a state-of-the art cloud infrastructure which is able to process these detailed second-life battery cell measurements coming from the battery systems operated in the field. As an example, we process cell voltage and temperature measurements of each individual cell in a battery energy storage system, which holds up to 216 cells, and with a granularity of 1 second.
We have developed the first algorithms using this granular data for state estimation and increased safety of second-life batteries. We have also created multiple dashboards to remotely monitor the systems in real time and with high granularity, allowing us to detect issues remotely and almost instantaneously.
We have also demonstrated multiple energy management applications with these second-life battery energy storage systems. Local applications, such as self-consumption and reactive power control have been demonstrated, as well day-ahead energy market price arbitraging.
We have demonstrated a first prototype of our second-life Battery Energy Storage System with the developed integrated Battery and Management System. Two systems have been developed and tested, containing two types of EV battery modules at two different sites. We have submitted a patent on the mechanical design to allows for multiple types of EV batteries to be used for stationary energy.
We have demonstrated three different applications with second-life batteries: maximising self-consumption, performing reactive power control and performing day-ahead arbitraging. The batteries have been shown to perform all these objectives without major issues.
We have develop our Battery Cloud to process detailed data generated from these second-life battery systems in the field. We have implemented first state estimation algorithms. The generated data of the demonstration systems will, together with new data from new systems installed in the remainder of the project, be used to further improve the algorithms and advance the state of the art. We are in the process of applying advanced artificial intelligence to improve our understanding of second-life batteries, their safe operation and maximize their value for stationary energy storage
Third party review on certifications and norms for the developed second-life Battery Energy Storage System has been started with first positive results obtained.