@article{Ma2026, 
author = {Wenqing Ma and Mingjuan Gao and Jianping Ma and Haiyang Gao and Xianhong Li and Yuyan Wang and Lihan Cai and Longhua Ding and Aizhu Wang and Xin Yu and Xizheng Liu},
title = {A kinetic window framework governing depth of discharge-dependent charging in Li–CO2 batteries},
year = {2026},
journal = {Nano Research},
keywords = {Kinetic window, Depth of discharge, Constant-voltage charging, Li–CO2 battery, Discharge product evolution},
url = {https://www.sciopen.com/article/10.26599/NR.2026.94909261},
doi = {10.26599/NR.2026.94909261},
abstract = {The sluggish decomposition kinetics of insulating discharge products impose large charging overpotentials and limit the practical application of Li–CO2 batteries. While constant-voltage charging has shown promise in overcoming kinetic barriers, the optimal charging voltage and its evolution with depth of discharge remain unclear. Here we establish, for the first time, a kinetic-window framework that identifies the depth of discharge (DOD) as the master variable governing the feasible voltage range for reversible operation in a model Ru@rGO cathode with 1 M LiTFSI/TEGDME electrolyte. The lower bound of this window rises progressively with increasing depth of discharge, driven by continuous accumulation of crystalline Li2CO3 and carbon that thickens the passivation layer, whereas Li2C2O4 persists at a quasi-steady level through a dynamic cycle of formation, disproportionation, and regeneration. Guided by this framework, we demonstrate that the shallow-optimized 4.0 V protocol fails at deeper discharge, while 4.2 V supports 87 stable cycles at 500 μAh cm–2. At 1000 μAh cm–2, even 4.4 V fails to sustain long-term operation, as the required driving force exceeds the electrolyte stability limit. This work establishes DOD as the master variable for protocol design and offers a universal, boundary-governed principle that can be extended to other metal–gas batteries facing similar polarization-accumulation challenges.}
}