Journal
NATURE MATERIALS
Volume 19, Issue 9, Pages 1006-+Publisher
NATURE RESEARCH
DOI: 10.1038/s41563-020-0667-y
Keywords
-
Categories
Funding
- Research Grant Council of the Hong Kong Special Administrative Region, China [CUHK14307318]
Ask authors/readers for more resources
Developing low-cost and eco-friendly aqueous electrolytes with a wide voltage window is critical to achieve safe, high-energy and sustainable Li-ion batteries. Emerging approaches using highly concentrated salts (21-55 m (mol kg(-1))) create artificial solid-electrode interfaces and improve water stability; however, these approaches raise concerns about cost and toxicity. Molecular crowding is a common phenomenon in living cells where water activity is substantially suppressed by molecular crowding agents through altering the hydrogen-bonding structure. Here we demonstrate a 'molecular crowding' electrolyte using the water-miscible polymer poly(ethylene glycol) as the crowding agent to decrease water activity, thereby achieving a wide electrolyte operation window (3.2 V) with low salt concentration (2 m). Aqueous Li4Ti5O12/LiMn2O4 full cells with stable specific energies between 75 and 110 W h kg(-1) were demonstrated over 300 cycles. Online electrochemical mass spectroscopy revealed that common side reactions in aqueous Li-ion batteries (hydrogen/oxygen evolution reactions) are virtually eliminated. This work provides a path for designing high-voltage aqueous electrolytes for low-cost and sustainable energy storage. Developing cheap and sustainable aqueous electrolytes with a wide voltage window is key to achieving safe and high-energy Li-ion batteries. An electrolyte using the polymer poly(ethylene glycol) as a crowding agent to decrease water activity achieves a wide operation window at low salt concentration.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available