Zhang Shengnan, Li Yuhang, Bannenberg Lars J, Liu Ming, Ganapathy Swapna, Wagemaker Marnix
Section Storage of Electrochemical Energy, Radiation Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft, Netherlands.
Shenzhen Key Laboratory of Power Battery Safety and Shenzhen Geim Graphene Center, Tsinghua Shenzhen International Graduate School, Tsinghua University, Guangdong 518055, China.
Sci Adv. 2024 Jan 19;10(3):eadj8889. doi: 10.1126/sciadv.adj8889. Epub 2024 Jan 17.
Formation cycling is a critical process aimed at improving the performance of lithium ion (Li-ion) batteries during subsequent use. Achieving highly reversible Li-metal anodes, which would boost battery energy density, is a formidable challenge. Here, formation cycling and its impact on the subsequent cycling are largely unexplored. Through solid-state nuclear magnetic resonance (ssNMR) spectroscopy experiments, we reveal the critical role of the Li-ion diffusion dynamics between the electrodeposited Li-metal (ED-Li) and the as-formed solid electrolyte interphase (SEI). The most stable cycling performance is realized after formation cycling at a relatively high current density, causing an optimum in Li-ion diffusion over the Li-metal-SEI interface. We can relate this to a specific balance in the SEI chemistry, explaining the lasting impact of formation cycling. Thereby, this work highlights the importance and opportunities of regulating initial electrochemical conditions for improving the stability and life cycle of lithium metal batteries.
形成循环是一个关键过程，旨在提高锂离子（Li-ion）电池在后续使用过程中的性能。实现高度可逆的锂金属阳极，这将提高电池能量密度，是一项艰巨的挑战。在此，形成循环及其对后续循环的影响在很大程度上尚未得到探索。通过固态核磁共振（ssNMR）光谱实验，我们揭示了电沉积锂金属（ED-Li）与形成的固体电解质界面（SEI）之间锂离子扩散动力学的关键作用。在相对较高的电流密度下进行形成循环后，可实现最稳定的循环性能，从而在锂金属-SEI界面上实现锂离子扩散的最佳状态。我们可以将此与SEI化学中的特定平衡联系起来，解释形成循环的持久影响。因此，这项工作突出了调节初始电化学条件对于提高锂金属电池稳定性和生命周期的重要性和机遇。
