An accelerated aging test procedure for lithium-ion battery based on a dual-temperature approach

Lithium-ion batteries (LiBs) are essential for diverse applications, but their degradation—driven by aging mechanisms such as solid electrolyte interface (SEI) formation, lithium plating, and electrode particle cracking—limits their performance and lifespan. These mechanisms result in degradation modes such as lithium inventory loss and active material depletion. Understanding these processes requires extensive aging tests, which are time-consuming and costly. Accelerated aging tests aim to expedite this process while preserving the same aging mechanisms observed under normal conditions. Among stress factors, temperature is widely used, as higher temperatures accelerate SEI growth, while lower temperatures promote lithium plating. However, conventional accelerated tests often achieve limited acceleration or unintentionally alter aging mechanisms. To address this, we propose a novel accelerated cycle aging procedure using dual-temperature conditions—charging at 20 °C and discharging at 40 °C. This approach balances SEI growth and lithium plating stress, replicating normal aging at 25 °C while achieving an acceleration factor of more than 5 or even 8. The method was validated through experiments comparing the proposed test with a reference non-accelerated aging test on identical batteries. The results suggest that this approach effectively preserves aging mechanisms, offering a reliable and efficient pathway for battery aging studies.