Discovering high-efficiency cathode presodiation additives for Na-ion batteries via high-throughput screening.

Abstract

Presodiation represents a crucial strategy for compensating the capacity loss and boosting energy density in practical Na-ion batteries. Through high-throughput screening, we identify 52 promising candidates as potential presodiation additives. Experimental validation confirms that several screened compounds, including Na₄FeO₄ (NFO), Na₄TiO₄, Na₅FeO₄, and Na₅NiO₄, exhibit high compensating capacities up to 537 milliampere-hours per gram (mAh g^-1). Notably, NFO delivers an irreversible capacity of 451 mAh g^-1, and, critically, 94.5% of its capacity is delivered below 4 volts. The presodiation mechanism of NFO is comprehensively studied by multiscale investigations combining DFT, DEMS, and synchrotron XRD/XAS. Full-cell tests of NFO demonstrate its universal efficacy across diverse Na-ion cathode chemistry, exhibiting boosted energy density and cycle stability. In particular, the incorporation of NFO increases the initial discharge capacity of the O3-NFM full cell from 109.4 to 141.3 mAh g^-1, with 83% retention after 200 cycles. This work not only establishes several highly effective cathode presodiation additives but also provides a variety of promising candidates for future research avenues.