LiFePO4 spray drying scale-up and carbon-cage for improved cyclability

JOURNAL OF POWER SOURCES

卷:462

Article

Rigamonti, Marco G.¹  Chavalle, Marc²  Li, He¹  Antitomaso, Philippe³  Hadidi, Lida³  Stucchi, Marta⁴  Galli, Federico¹  Khan, Hayat¹  Dolle, Mickael³  Boffito, Daria C.¹  Patience, Gregory S.¹ 

[1] Polytech Montreal, Dept Chem Engn, CP 6079, Montreal, PQ H3C 3A7, Canada

[2] Ecole Super Phys & Chim Ind Ville Paris, Lab Soft Matter Sci & Engn, 10 Rue Vauquelin, Paris 75005, France

[3] Univ Montreal, Lab Chem & Electrochem Solids, 2900 Boul Edouard Montpetit, Montreal, PQ H3T 1J4, Canada

[4] Univ Milan, Dipartimento Chim, Via Golgi 19, Milan 20133, Italy

关键词: LiFePO4/C cathode material;    Nanoparticle;    Spray drying;    Pyrolysis;    Carbon-cage;    Electrochemical test;   

DOI  :  10.1016/j.jpowsour.2020.228103

来源: Elsevier

【 摘 要 】

The growing market for electrical vehicles requires inexpensive, long-lasting batteries. LiFePO4 (LFP) melt-synthesized from ore concentrate fits this role, but the manufacturing process requires additional steps that includes grinding large ingots into a nanoparticle suspension followed by a dessication step. Spray drying, rather than tray drying, creates a mesopomus powder that enhances wettability. Adding lactose and high-Mw polyvinyl alcohol (PVA) to the suspension of nanostructures followed by pyrolysis, creates a carbon-cage that interconnects the cathode nanoparticles, imparting better capacity (LiFePO4/C: 161 mA h g(-1) at 0.1C), discharge rate (flat plateau, 145 mA h g(-1) at 5C), and cyclability (91% capacity retention after 750 cycles at 1C). Particle size affects battery stability; PVA increases the suspension's viscosity and alters the powder morphology, from spherical to hollow particles. A model describes the non-Newtonian suspension's rheology changing: shear, temperature, LFP and PVA loading. Carbon precursors prevent the nanoparticles from sintering during calcination but lactose gasifies 50% of the carbon, according to the chemical and allotropic composition measurements (CS analyzer, XPS, and Raman). The carbon-cage imparts micmporosity and we correlate the SEM and TEM powder's morphology with N2 physisorption porosimetry. Ultrasonication of the suspension fragments the PVA chain, which is detrimental to the final cathode performance.

【 授权许可】

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