Raising the cycling stability of aqueous lithium-ion batteries by eliminating oxygen in the electrolyte

Nat Chem. 2010 Sep;2(9):760-5. doi: 10.1038/nchem.763. Epub 2010 Aug 8.

Abstract

Aqueous lithium-ion batteries may solve the safety problem associated with lithium-ion batteries that use highly toxic and flammable organic solvents, and the poor cycling life associated with commercialized aqueous rechargeable batteries such as lead-acid and nickel-metal hydride systems. But all reported aqueous lithium-ion battery systems have shown poor stability: the capacity retention is typically less than 50% after 100 cycles. Here, the stability of electrode materials in an aqueous electrolyte was extensively analysed. The negative electrodes of aqueous lithium-ion batteries in a discharged state can react with water and oxygen, resulting in capacity fading upon cycling. By eliminating oxygen, adjusting the pH values of the electrolyte and using carbon-coated electrode materials, LiTi(2)(PO(4))(3)/Li(2)SO(4)/LiFePO(4) aqueous lithium-ion batteries exhibited excellent stability with capacity retention over 90% after 1,000 cycles when being fully charged/discharged in 10 minutes and 85% after 50 cycles even at a very low current rate of 8 hours for a full charge/discharge offering an energy storage system with high safety, low cost, long cycling life and appropriate energy density.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Electric Power Supplies*
  • Electrochemistry
  • Electrodes*
  • Electrolytes / chemistry*
  • Lithium / chemistry*
  • Oxygen / chemistry*

Substances

  • Electrolytes
  • Lithium
  • Oxygen