Sodium Squarate (Na2C4O4) Powder as Cathode Pre-Sodiation Additive for Sodium-Ion Battery, 10 g/bottle, CSIBCPSASS

Sodium squarate (Na2C4O4), also known as disodium squarate, is an emerging organic sacrificial sodium salt used for the pre-sodiation of sodium-ion batteries (SIBs) and sodium-ion capacitors (SICs). It is considered a "green" and high-efficiency alternative to inorganic supplements because it decomposes during the first charge into environmentally benign gaseous byproducts (CO or CO2) and sodium ions, leaving behind virtually no dead weight or metal residues. The key features of Na2C4O4 as sodium pre-sodiation additive are: (1) High Theoretical Capacity: It offers a high specific capacity of 339 mAh/g, which is significantly higher than many inorganic sodium-rich additives. (2) Oxidation Potential: It decomposes irreversibly at approximately 3.6 V (vs. Na/Na⁺). This potential is low enough to be compatible with standard sodium-ion electrolytes, preventing side reactions. (3) Gaseous Byproducts: Upon decomposition, the squarate anion {(C4O4)2-} primarily converts into Carbon Monoxide (CO) and Carbon Dioxide (CO2). These gases are easily removed during the battery's degassing phase.

Part Number	CSIBCPSASS (C-SIB-CPSA-SS)
Appearance	Pristine Na2C4O4: White Na2C4O4/Carbon Composite: Grey or Black
Chemical Formula/Structure	Na2C4O4
Additive Types	(1) Pristine Na2C4O4 (2) Na2C4O4/Carbon composite (carbon content is 5 wt%)
Purity	>99%
pH	7.5-8.5
Addition Amount	2.5-5.0 wt%
Package Size	10 g/bottle

Notes: Please try to store the Na2C4O4 powder in a dry place (glovebox is the best option). 

References: 

1. L. Sbrascini, et al. ffect of Presodiation Additive on Structural and Interfacial Stability of Hard Carbon | P2-Na0.66Mn0.75Ni0.2Mg0.05O2 Full Cel, Batteries & Supercaps, 2024, 7, e202400207.
2. S. Lin, et al. Research Progress and Perspectives on Pre-Sodiation Strategies for Sodium-Ion Batteries, Adv. Funct. Mater.. 2024, 34, 2409628.