Yu Honggang, Jin Haizu, Zhao Fenggang, Li Zhen, Huang Yunhui
State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
Contemporary Amperex Technology Co., Ltd, Ningde 352100, China.
ACS Appl Mater Interfaces. 2024 Oct 23;16(42):57112-57119. doi: 10.1021/acsami.4c07052. Epub 2024 Oct 9.
Lithium-ion battery (LIB) has gained significant recognition for the power cell market owing to its impressive energy density and appealing cost benefit. Among various cathodes, a high-voltage cobalt-poor lithium nickel manganese cobalt oxide cathode (Co-poor NCM cathode) has been considered as a promising strategy to enhance its energy density. Despite these advantages, high-voltage Co-poor NCM cathode-graphite full battery usually suffers from poor rate performance. However, fast charging has been a key indicator for widespread application of power batteries. Although many efforts have been made to improve the charging performance of fresh batteries, few works investigate the charging ability during calendar aging and cycling aging of high-voltage Co-poor NCM cathode-graphite full battery. In this work, we found that the charging ability becomes worse during calendar aging and cycling aging. Results showed that the increasing charge transfer resistance from the cathode is the major obstacle to achieving fast charging during the aging process. To address the problem, high-voltage AlO-coated Co-poor NCM cathode successfully prepared via a simple atomic layer deposition (ALD) method has been developed to reduce the decay of charging performance during calendar aging and cycling aging. AlO-coated NCM cathode can effectively reduce the growth rate of the resistance of cathode, which is benefiting from the conversion of AlO into LiAlO with high ionic conductivity and the restriction formation of rock salt phase. Benefiting from the decreased charge transfer resistance of the NCM cathode, the mismatch of the lithium-ion reaction kinetics is well alleviated, thus effectively reducing the polarization under fast charging. As a result, AlO-coated NCM cathode-graphite full battery shows the slow deterioration of charging performance during the aging process. This work provides a promising strategy for constructing fast-charging batteries during calendar aging and cycling aging.
锂离子电池（LIB）因其令人印象深刻的能量密度和诱人的成本效益在动力电芯市场获得了显著认可。在各种阴极材料中，高压贫钴锂镍锰钴氧化物阴极（贫钴NCM阴极）被视为提高其能量密度的一种有前景的策略。尽管有这些优点，但高压贫钴NCM阴极-石墨全电池通常倍率性能较差。然而，快速充电一直是动力电池广泛应用的关键指标。尽管已经做出了许多努力来提高新电池的充电性能，但很少有研究调查高压贫钴NCM阴极-石墨全电池在日历老化和循环老化过程中的充电能力。在这项工作中，我们发现该全电池在日历老化和循环老化过程中充电能力变差。结果表明，阴极电荷转移电阻的增加是老化过程中实现快速充电的主要障碍。为了解决这个问题，通过简单的原子层沉积（ALD）方法成功制备了高压AlO包覆的贫钴NCM阴极，以减少日历老化和循环老化过程中充电性能的衰减。AlO包覆的NCM阴极可以有效降低阴极电阻的增长速率，这得益于AlO转变为具有高离子电导率的LiAlO以及抑制岩盐相的形成。受益于NCM阴极电荷转移电阻的降低，锂离子反应动力学的不匹配得到了很好的缓解，从而有效降低了快速充电下的极化。结果，AlO包覆的NCM阴极-石墨全电池在老化过程中充电性能的劣化较慢。这项工作为在日历老化和循环老化过程中构建快速充电电池提供了一种有前景的策略。
