In lithium-ion batteries, high charging voltages can increase the amount of lithium extracted from the positive electrode, potentially enhancing capacity. However, this also risks degradation of the positive electrode due to multiple pathways. Prior studies have identified degradation mechanisms including particle fracture, surface reconstruction, transition metal dissolution, and electrolyte oxidation. These mechanisms interact in complex ways, making it difficult to pinpoint their individual effects on battery performance and to identify the optimal charging voltage that balances capacity and stability.

Now, Kenneth J. Takeuchi and colleagues in the USA tackle this issue by deconvoluting the degradation mechanisms in commercially relevant graphite/LiNi_0.8Mn_0.1Co_0.1O₂ (NMC) pouch cells. They cycled different batteries across various voltage windows while varying the electrolyte formulation to isolate specific degradation pathways.

在锂离子电池中，高充电电压可以增加从正极提取的锂量，从而有可能提高容量。然而，这也存在由于多种途径而导致正极退化的风险。先前的研究已经确定了降解机制，包括颗粒破裂、表面重建、过渡金属溶解和电解质氧化。这些机制以复杂的方式相互作用，因此很难查明它们对电池性能的影响，也很难确定平衡容量和稳定性的最佳充电电压。

现在，美国的 Kenneth J. Takeuchi 及其同事通过对商业相关的石墨/LiNi _0.8 Mn _0.1 Co _0.1 O ₂ (NMC) 软包电池中的降解机制进行解卷积来解决这个问题。他们在不同的电压范围内循环不同的电池，同时改变电解质配方以隔离特定的降解途径。