The concept of repurposing retired electric vehicle (EV) batteries for industrial applications has gained traction as a sustainable solution to extend battery life while reducing waste. Second-life batteries, which no longer meet the demanding energy and power requirements of EVs, often retain sufficient capacity for less intensive applications such as forklifts, airport ground support equipment (GSE), and other industrial machinery. This approach not only delays battery recycling but also offers economic advantages by lowering upfront costs compared to new battery systems.
Industrial machinery such as forklifts and GSE have distinct performance requirements that make them suitable candidates for second-life battery deployment. Forklifts, for instance, require high peak power capability for lifting and moving heavy loads, along with cyclic workload tolerance to endure frequent charge and discharge cycles during shift operations. Airport GSE, including baggage tugs and aircraft pushback tractors, demand reliable energy delivery under variable load conditions. Second-life batteries must be carefully evaluated to ensure they meet these operational demands.
Performance assessments of second-life batteries in industrial applications focus on key metrics such as remaining capacity, internal resistance, and cycle life. Studies indicate that EV batteries retired at 70-80% of their original capacity can still provide adequate performance in forklift applications, where energy density requirements are lower than in EVs. However, peak power capability remains critical, as industrial equipment often requires short bursts of high current. Battery management system (BMS) recalibration is essential to adapt second-life batteries to their new use cases. The BMS must be reprogrammed to account for reduced capacity and updated safety thresholds to prevent over-discharge or overheating.
Total cost of ownership (TCO) analysis reveals that second-life batteries can offer significant savings compared to traditional power sources such as lead-acid batteries or new lithium-ion systems. While lead-acid batteries have lower upfront costs, their shorter lifespan and higher maintenance requirements result in higher long-term expenses. Second-life lithium-ion batteries, by contrast, benefit from the remaining cycle life of repurposed cells, reducing replacement frequency. A comparative TCO breakdown for a typical forklift fleet might show the following:
Battery Type | Initial Cost | Cycle Life | Maintenance Cost | Replacement Frequency
Lead-Acid | Low | 500-1000 cycles | High | 2-3 years
New Li-ion | High | 2000-3000 cycles | Low | 5-7 years
Second-Life Li-ion | Moderate | 1000-1500 cycles | Low | 3-5 years
Safety standards for industrial environments impose strict requirements on battery systems, particularly concerning thermal stability and mechanical robustness. Second-life batteries must comply with regulations such as UL 2580 for industrial equipment and IEC 62619 for stationary storage. Key safety considerations include reinforced casing to withstand vibrations and impacts, as well as enhanced thermal monitoring to detect potential faults early. Flame-retardant additives and improved separator materials may be incorporated to mitigate thermal runaway risks.
The integration of second-life batteries into industrial machinery also involves logistical challenges, including battery sorting, testing, and reconfiguration. Grading systems categorize retired EV batteries based on remaining capacity and health status, ensuring only suitable units are redeployed. Standardized testing protocols assess performance under simulated industrial conditions, including peak load testing and cyclic endurance evaluations.
In conclusion, second-life batteries present a viable and sustainable alternative for powering industrial machinery, offering a balance between performance, cost, and environmental benefits. By recalibrating battery management systems and adhering to stringent safety standards, industries can effectively utilize repurposed EV batteries in applications such as forklifts and airport GSE. The total cost of ownership analysis supports the economic feasibility of this approach, particularly when compared to traditional lead-acid systems. As battery recycling and repurposing infrastructure continues to mature, second-life applications are expected to play an increasingly important role in industrial energy storage.