Chen Jinhang, Onah Obinna E, Cheng Yi, Silva Karla J, Choi Chi Hun Will, Chen Weiyin, Xu Shichen, Eddy Lucas, Han Yimo, Yakobson Boris I, Zhao Yufeng, Tour James M
Department of Chemistry, Rice University, 6100 Main Street, Houston, TX, 77005, USA.
Applied Physics Program and Smalley-Curl Institute, Rice University, 6100 Main Street, Houston, TX, 77005, USA.
Small Methods. 2025 Jan;9(1):e2400680. doi: 10.1002/smtd.202400680. Epub 2024 Sep 9.
Lithium iron phosphate (LiFePO, LFP) batteries are widely used in electric vehicles and energy storage systems due to their excellent cycling stability, affordability and safety. However, the rate performance of LFP remains limited due to its low intrinsic electronic and ionic conductivities. In this work, an ex situ flash carbon coating method is developed to enhance the interfacial properties for fast charging. A continuous, amorphous carbon layer is achieved by rapidly decomposing the precursors and depositing carbon species in a confined space within 10 s. Simultaneously, different heteroatoms can be introduced into the surface carbon matrix, which regulates the irregular growth of cathode-electrolyte interphase (CEI) and selectively facilitates the inorganic region formation. The inorganic-rich, hybrid conductive CEI not only promotes electron and ion transport but also restricts parasitic side reactions. Consequently, LFP cathodes with fluorinated carbon coatings exhibited the highest capacity of 151 mAh g at 0.2 C and 96 mAh g at 10 C, indicating their excellent rate capability over commercial LFP (58 mAh g at 10 C). This solvent-free, versatile surface modification is shown for other electrode materials, providing an efficient platform for electrode-electrolyte interphase engineering through a surface post-treatment.
磷酸铁锂（LiFePO，LFP）电池因其出色的循环稳定性、经济性和安全性而广泛应用于电动汽车和储能系统。然而，由于其固有的低电子和离子电导率，LFP的倍率性能仍然有限。在这项工作中，开发了一种非原位快速碳涂层方法来增强界面性能以实现快速充电。通过在前体快速分解并在10秒内在受限空间内沉积碳物种，获得了连续的无定形碳层。同时，可以将不同的杂原子引入表面碳基体，这调节了阴极-电解质界面（CEI）的不规则生长并选择性地促进无机区域的形成。富含无机成分的混合导电CEI不仅促进电子和离子传输，还限制寄生副反应。因此，具有氟化碳涂层的LFP阴极在0.2 C时表现出最高容量为151 mAh g，在10 C时为96 mAh g，表明其倍率性能优于商用LFP（在10 C时为58 mAh g）。这种无溶剂的通用表面改性方法也适用于其他电极材料，通过表面后处理为电极-电解质界面工程提供了一个有效的平台。
