School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States.
Nano Lett. 2012 Sep 12;12(9):5048-54. doi: 10.1021/nl302879t. Epub 2012 Aug 9.
Energy generation and energy storage are two distinct processes that are usually accomplished using two separated units designed on the basis of different physical principles, such as piezoelectric nanogenerator and Li-ion battery; the former converts mechanical energy into electricity, and the latter stores electric energy as chemical energy. Here, we introduce a fundamental mechanism that directly hybridizes the two processes into one, in which the mechanical energy is directly converted and simultaneously stored as chemical energy without going through the intermediate step of first converting into electricity. By replacing the polyethylene (PE) separator as for conventional Li battery with a piezoelectric poly(vinylidene fluoride) (PVDF) film, the piezoelectric potential from the PVDF film as created by mechanical straining acts as a charge pump to drive Li ions to migrate from the cathode to the anode accompanying charging reactions at electrodes. This new approach can be applied to fabricating a self-charging power cell (SCPC) for sustainable driving micro/nanosystems and personal electronics.
能量生成和能量存储是两个截然不同的过程，通常使用基于不同物理原理的两个分离单元来完成，例如压电纳米发电机和锂离子电池；前者将机械能转化为电能，后者将电能存储为化学能。在这里，我们介绍一种将这两个过程直接结合为一体的基本机制，其中机械能直接转化并同时存储为化学能，而无需先转化为电能这一中继步骤。通过用压电聚偏二氟乙烯 (PVDF) 薄膜代替传统锂离子电池的聚乙烯 (PE) 隔膜，由机械应变产生的 PVDF 薄膜的压电电势充当电荷泵，驱动锂离子从阴极迁移到阳极，同时在电极上进行充电反应。这种新方法可用于制造自充电电源单元 (SCPC)，以驱动可持续的微/纳系统和个人电子设备。
