Material balance in the O₂ electrode of Li–O₂ cells with a porous carbon electrode and TEGDME-based electrolytes

Abstract

The material balance in the O2 electrode of a Li–O2 cell with a Ketjenblack-based porous carbon electrode and a tetraethylene glycol dimethyl ether-based electrolyte under more practical conditions of less electrolyte amount and high areal capacity.

Lithium-Ion-Conducting Ceramics-Coated Separator for Stable Operation of Lithium Metal-Based Rechargeable Batteries

“…During the discharge process, the cell exhibited a voltage plateau at approximately 2.6 V. In the initial and middle parts of the charging process, a stable voltage plateau appeared at approximately 3.5–3.6 V, and the voltage gradually increased to 4.0 V at the end of the charging process. These results are characteristic of the charging profile of LOB cells containing LiNO 3 and LiBr as redox mediators [ 44 , 45 ]. However, such stable discharge/charge voltages were only maintained up to the 3rd cycle, and the overpotential increased at the end of charging in the 4th~6th cycles.…”

Overlooked Factors Required for Electrolyte Solvents in Li–O2 Batteries: Capabilities of Quenching 1O2 and Forming Highly‐Decomposable Li2O2

“…Importantly, the performance of the LOB with the DMA‐based electrolyte was evaluated under a condition of the rate of 0.4 mA cm −2 , the capacity of 4 mAh cm −2 , and the electrolyte volume of 31.8 μL cm −2 . Notably, this condition is relatively strict than those used in most of the previous related studies, and the feasibility of large gravimetric energy density can be verified in this test condition [26] …”

“…The performance of LOBs with amide‐based electrolytes was compared with that of LOBs with G4‐based electrolytes. In the present study, an electrolyte containing Br − /Br 3 − and NO 2 − /NO 2 redox couples as mediators (0.5 M LiNO 3 –0.5 M lithium bis(trifluoromethylsulfonyl)azanide (LiTFSA)–0.2 M LiBr/G4) was selected as the sample for comparison unless otherwise specified because an electrolyte with this composition has shown better performance than electrolytes without a redox mediator [26] . Hereinafter, these G4‐based electrolytes with and without the redox mediators are referred to as G4/RM and G4, respectively.…”

“…In fact, the best cyclability was obtained for the electrolyte based on DMA, which is considered the least tolerant against O 2 − among the examined amides. Importantly, although many previous studies have not sufficiently examined the cycle test conditions with an awareness of the large gravimetric energy density that is inherently expected for LOBs, [26] we evaluated the performance of the LOB with the DMA‐based electrolyte under a condition where the feasibility of large gravimetric energy density can be verified [3] . The results demonstrate that the capabilities of quenching 1 O 2 and forming highly decomposable Li 2 O 2 during discharging inherent to DMA can be the critical reasons for the superior performance under the conditions for the present work.…”

“…In the present study, an electrolyte containing Br À /Br 3 À and NO 2 À /NO 2 redox couples as mediators (0.5 M LiNO 3 -0.5 M lithium bis(trifluoromethylsulfonyl)azanide (LiTFSA)-0.2 M LiBr/ G4) was selected as the sample for comparison unless otherwise specified because an electrolyte with this composition has shown better performance than electrolytes without a redox mediator. [26] Hereinafter, these G4-based electrolytes with and without the redox mediators are referred to as G4/RM and G4, respectively. Importantly, the performance of the LOB with the DMA-based electrolyte was evaluated under a condition of the rate of 0.4 mA cm À 2 , the capacity of 4 mAh cm À 2 , and the electrolyte volume of 31.8 μL cm À 2 .…”