Techno-financial investigation of second-life of Electric Vehicle batteries for energy imbalance services in the Irish electricity market

As EVs becoming a viable choice in transportation systems, worries arise about the massive amount of environmentally hazardous electrochemical waste generated at end of life. A sustainable life cycle approach suggests exploring well-defined waste management strategies to deal with the upcoming waste. These strategies either aim at recycling if there is no potential for a second life or repurposing if the end-of-life automobile batteries are sufficiently healthy. However, the health of end-of-life batteries are not the only measure for their feasibility in a second application and it partly depends on the financial viability as well. Second life market alignment, the sensible second-use profit-making considering revenue-cost balance as well as other suppliers' side inertias and preferences for battery secondary supply instead of reuse must be enlightened in a circular waste management system. This work aims to address some of the financial considerations of battery reuse by conducting a marginal revenue-cost analysis for energy services in the Irish electricity market while incorporating the battery technical limitations into the assessment. The marginal analysis shows how much investment in reused batteries would keep the financial balance of the system. Results show that the investment of retired batteries with 90% SOH for arbitrage trading in the imbalance energy market would be profitable when their purchase price is below average 60% of the batteries' original price, while for 85% and 80%, this value is estimated up to 25% and 20%, respectively. However, hybridizing their operation with other non-energy services would make their investment more profitable.