PNNL

Abstract

The pouch-type Li-air batteries operated in ambient condition are reported in this work. The battery used a heat sealable plastic membrane as package material, O2¬ diffusion membrane and moisture barrier. The large variation in internal resistance of the batteries is minimized by a modified separator which can bind the cell stack together. The cells using the modified separators show improved and repeatable discharge performances. It is also found that addition of about 20% of 1,2-dimethoxyethane (DME) in PC:EC (1:1) based electrolyte solvent improves can improve the wetability of carbon electrode and the discharge capacities of Li-air batteries, but further increase in DME amount lead to a decreased capacity due to increase electrolyte loss during discharge process. The pouch-type Li-air batteries with the modified separator and optimized electrolyte has demonstrated a specific capacity of 2711 mAh g-1 based on carbon and a specific energy of 344 Wh kg-1 based on the complete batteries including package.