Context:
Sales of electric vehicles in Europe rose by over 20% in 2024 compared with the previous year, reaching almost 3.2 million units. However, the phasing-out of subsidies in some countries, notably Germany, has slowed sales growth, leading to a significant build-up of inventories for certain models. This imbalance between supply and demand, amplified by increased competition and fluctuating raw material prices, creates major challenges for automakers.
Recent studies show that the natural discharge (or calendar aging) of lithium-ion batteries, when vehicles are in storage, can cause significant degradation, often more severe than regular charge and discharge cycles. Stored batteries are subject to factors such as temperature fluctuations, self-discharge, and internal chemical reactions, accelerating capacity loss and increasing internal resistance. These effects are particularly pronounced when batteries are stored in sub-optimal conditions.
Therefore, it is crucial for manufacturers to proactively manage their inventories to minimize the natural degradation of lithium-ion batteries, a situation which can be more damaging when they are simply stored rather than actively used.
