Abstract
The inhomogeneous Li electrodeposition of lithium metal electrode has been a major impediment to the realization of rechargeable lithium metal batteries. Although single ion conducting ionomers can induce more homogeneous Li electrodeposition by preventing Li + depletion at Li surface, currently available materials do not allow room-Temperature operation due to their low room temperature conductivities. In the paper, we report that a highly conductive ionomer/liquid electrolyte hybrid layer tightly laminated on Li metal electrode can realize stable Li electrodeposition at high current densities up to 10â €‰mAâ €‰cm â '2 and permit room-Temperature operation of corresponding Li metal batteries with low polarizations. The hybrid layer is fabricated by laminating few micron-Thick Nafion layer on Li metal electrode followed by soaking 1â €‰M LiPF 6 EC/DEC (1/1) electrolyte. The Li/Li symmetric cell with the hybrid layer stably operates at a high current density of 10â €‰mAâ €‰cm â '2 for more than 2000â €‰h, which corresponds to more than five-fold enhancement compared with bare Li metal electrode. Also, the prototype Li/LiCoO 2 battery with the hybrid layer offers cycling stability more than 350 cycles. These results demonstrate that the hybrid strategy successfully combines the advantages of bi-ionic liquid electrolyte (fast Li + transport) and single ionic ionomer (prevention of Li + depletion).
| Original language | English |
|---|---|
| Article number | 14458 |
| Journal | Scientific Reports |
| Volume | 5 |
| DOIs | |
| State | Published - 28 Sep 2015 |
Bibliographical note
Funding Information:This research was supported by two grants from the National Research Foundation of Korea funded by the Korean Government (MEST) (NRF-2009-0094219 and NRF-2014R1A1A2056199).