Long-life, high-energy-density acidic Zn-air batteries

Physical Sciences : Materials and Compounds

Available for licensing

Inventors

  • Arumugam Manthiram, Ph.D. , Mechanical Engineering
  • Longjun Li , University of Texas at Austin

Background/unmet need

Low-cost, high-energy-density batteries are being intensively pursued in recent years to electrify transportation and facilitate the efficient use of renewable energy sources. Metal-air batteries are receiving worldwide attention as they are powered by a high-energy metal anode and an inexhaustible, low-cost air cathode. Zn-air batteries (ZAB) are regarded as more practical metal-air battery system due to their low cost, safety, rechargeability, and good stability of Zn in aqueous solutions. However, the current ZABs suffer from CO2 ingression, dendrite problems at the Zn anode, zincate loss, low cell voltage (1.65 V), and high polarization and short cycle life of the air cathodes.

Invention Description

Inventors at UT Austin have developed acidic Zn-air batteries with decoupled air electrodes, which are promising to eliminate the problems of conventional ZABs. The ZAB prototype is composed of Zn metal anode, an alkaline anode electrolyte disposed adjacent the Zn metal anode, a decoupled air cathode including an oxygen reduction reaction (ORR) component and an oxygen evolution reaction (OER) component, wherein the ORR component and OER component are physically separate, an acidic catholyte disposed adjacent the decoupled air cathode, and a solid electrolyte disposed between the alkaline anode electrolyte and the acidic catholyte. The theoretical cell voltage is 2.5, which is 0.85 V higher than the conventional alkaline ZAB. In addition, the cell can be cycled for hundreds of hours without significant degradation.

Benefits/Advantages

  • Higher cell voltage
  • Longer cycle life
  • Incorporation of a solid electrolyte as the separator blocks Zn dendrites and eliminates zincate loss
  • CO2 compatible operation

Features

  • Higher voltage
  • The soluble zincate is stored and trapped in the anode chamber, improving the utilization of active materials.
  • Solid electrolyte will block Zn dendrites.
  • High cell efficiency

Market potential/applications

Battery manufacturers, energy storage markets

Development Stage

Lab/bench prototype

IP Status

  • 1 U.S. patent application filed