Dry Pouch Cells with NVP + Hard Carbon for Sodium-Ion Battery, 1 Ah/pcs/pack, CSIBAFDPCNVPHC

Assembling Dry Pouch Cells with Na3V2(PO4)3 (NVP) as the cathode and Hard Carbon (HC) as the anode is a premier strategy for developing high-power, long-life Sodium-Ion Batteries (SIBs). NVP is a NASICON-structured (Sodium Super Ionic Conductor) material. Its open 3D framework allows for incredibly fast sodium-ion diffusion, which, when paired with the disordered "house-of-cards" structure of Hard Carbon, creates a battery capable of extremely high C-rates (fast charging/discharging).

For this specific chemistry, the dry assembly phase serves as a vital "dehydration" gate: (1) Eliminating Structural Water: NASICON materials like NVP can trap trace amounts of moisture within their large crystalline channels. Placing the assembled dry pouch in a High-Vacuum Oven (110-120 °C) ensures that this moisture is removed before it can react with the sodium electrolyte. (2) Hard Carbon Degassing: Hard carbon is highly porous. In the dry state, a deep vacuum seal ensures that air trapped within these micropores is removed, facilitating complete "wetting" once the electrolyte is injected.

Testing Processes:

(1) Electrolyte Filling with recommended amount in glovebox.
(2) First Time Aging: 45°C, aging time ≥ 15h in an oven.
(3) Formation conditions: 45°C, 5 min rest; 0.02C constant current charging (10% theoretical capacity or 5 h); 0.1C constant current charging (30% theoretical capacity, 3 h); 5 min rest; total capacity is 40% or 8 h;
(4) Second Time Aging: 45°C, aging time ≥ 24h in a oven
(5) Battery Analyzer for charging and discharging.

References:

1. Y. Jin, et al., Low-solvation electrolytes for high-voltage sodium-ion batteries, Nat. Energy, 2022, 7, 718–725. 
2. B. Liu, et al., Super-wetting interface engineering of space-confined micron-sized alloying anodes for high-performance sodium-based dual-ion batteries, Matter, 2025, 8, 102294.