Abstract
One of the recent challenges in Li–O2 battery technology is the cycle life, which can be severely shortened by cathode passivation induced by discharge product accumulation; this can be eliminated by reducing the amount of discharge products. Herein, we report a feasibility study on the development of a Ga–Sn liquid metal (LM)-functionalized multiwalled carbon nanotubes (MWNTs) cathode. In a comparison of MWNT, LM, m-LM/MWNT (pre-mixed LM and MWNTs), and LM/MWNT (LM-modified MWNTs) cathodes, morphology analysis showed that small Li2O2 flakes rather than large crystals grow on the conductive Ga–Sn LM and MWNTs of the LM/MWNT cathode only. The decomposition of the flaky Li2O2 on the LM/MWNT cathode occurred at lower charge overpotentials, resulting in low polarization; thus, the cathode passivation and the consumption of the Li anode were both alleviated during the cyclic process. The LM/MWNT cathode significantly improved the cycle life, rate performance, and ultimate capacity of Li–O2 batteries.
Original language | English |
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Article number | 100559 |
Number of pages | 7 |
Journal | Materials Today Energy |
Volume | 18 |
Early online date | 12 Oct 2020 |
DOIs | |
Publication status | Published - 1 Dec 2020 |
Keywords
- Li-O2 batteries
- Ga-Sn liquid metal
- flaky Li2O2
- cathode passivation