Key Laboratory of Core Technology of High Specific Energy Battery and Key Materials for Petroleum and Chemical Industry, College of Energy, Soochow University, Suzhou, 215006, China.
College of Chemistry and Chemical Engineering, Nantong University, Seyuan 9, Nantong, 226000, China.
Nat Commun. 2023 Apr 20;14(1):2267. doi: 10.1038/s41467-023-37995-8.
Biphasic self-stratified batteries (BSBs) provide a new direction in battery philosophy for large-scale energy storage, which successfully reduces the cost and simplifies the architecture of redox flow batteries. However, current aqueous BSBs have intrinsic limits on the selection range of electrode materials and energy density due to the narrow electrochemical window of water. Thus, herein, we develop nonaqueous BSBs based on Li-S chemistry, which deliver an almost quadruple increase in energy density of 88.5 Wh L as compared with the existing aqueous BSBs systems. In situ spectral characterization and molecular dynamics simulations jointly elucidate that while ensuring the mass transfer of Li, the positive redox species are strictly confined to the bottom-phase electrolyte. This proof-of-concept of Li-S BSBs pushes the energy densities of BSBs and provides an idea to realize massive-scale energy storage with large capacitance.
双相自分层电池 (BSB) 为大规模储能提供了电池理念的新方向，成功降低了成本并简化了氧化还原液流电池的结构。然而，由于水的电化学窗口较窄，当前的水性 BSB 在电极材料和能量密度的选择范围上存在固有限制。因此，在此，我们基于 Li-S 化学开发了非水 BSB，与现有的水性 BSB 系统相比，能量密度几乎提高了四倍，达到 88.5 Wh·L。原位光谱表征和分子动力学模拟共同阐明，在确保 Li 的传质的同时，正氧化还原物质严格限制在底相电解质中。Li-S BSB 的这一概念验证推动了 BSB 的能量密度，并为实现具有大电容的大规模储能提供了思路。
