Full‐Cell Presodiation Strategy to Enable High‐Performance Na‐Ion Batteries

Abstract

As promising alternatives to lithium‐ion batteries, sodium‐ion batteries suffer from low coulombic efficiency, which stems from Na‐deficiency and unstable interfaces for both cathode and anode materials. Exhibiting a favorable solvation structure, Na‐naphthalene/tetrahydropyran (Na‐NP/THP) is screened and selected as a full‐cell presodiation solution for hard carbon (HC) anodes and a P‐2 type Na0.67Fe0.1Al0.1Mn0.8O2 (NFAM) cathode, which are both Na‐deficient. Through a wealth of characterizations, it is revealed that the proposed presodiation agent not only boosts the initial coulombic efficiency of both HC and NFAM electrodes effectively, but also facilitates robust solid–electrolyte interphase (SEI) and cathode–electrolyte interphase (CEI) on both electrodes. Consequently, the long‐term cycling and rate performance are greatly improved thanks to the stabilized structures of electrode materials. Furthermore, a proof‐of‐concept NFAM||HC pouch cell based on this presodiation strategy is assembled, showing a high reversible capacity and superior cycling performance. By offering a remedy to a full cell system subjected to severe Na‐deficiency, this work conceptually demonstrates a feasible strategy to fully tap the potential of high‐energy‐density materials in sodium‐ion batteries.

Lignin molecular sieving engineering enables high-plateau-capacity hard carbon anodes for sodium-ion batteries

“…This is consistent with the work reported by Wang et al , that hard carbon has unsatisfactory cycling performance at low current density. 46…”

Energy Band-Modulated SnO Anodes with Improved Rate Capacity and Initial Coulombic Efficiency for Sodium-Ion Batteries

“…It is obvious that the SnO@Bi@C-2 anode exhibits a much higher ICE of 80.67%, which is a significant increase compared to 57.38% for the SnO@C anode. Such a high ICE increment ∼23.29% is the largest one ever reported (seen in Figure g), except for the presodiation. , In addition, the SnO@Bi@C-2 anode also shows a relatively high sodiation voltage compared to the SnO@C anode, especially in the first discharge process shown in Figure a, suggesting the fast sodiation reaction kinetics. Particularly, in the desodiation process, different samples display similar voltage terraces at ∼0.60 and ∼0.77 V, demonstrating the low polarization in the fabricated anodes.…”

Sodium Acetate as Residual-Free Presodiation Additive for Enhancing the Energy Density of Sodium-Ion Batteries

“…This process significantly diminishes the available active sodium resource. Consequently, the initial Coulombic efficiency (ICE) and energy density of SIBs are adversely affected, posing challenges to the advancement and widespread adoption of SIBs. − To counterbalance the depletion of active sodium, a common practice involves incorporating an excess of cathode materials into the full cell. However, this approach notably diminishes the utilization efficiency of cathode materials and the overall energy density of the cell.…”