Limachi Claudia, Rogala Klaudia, Broszkiewicz Marek, Cabello Marta, Niedzicki Leszek, Armand Michel, Wieczorek Władysław
Faculty of Chemistry, Warsaw University of Technology, 00-664 Warsaw, Poland.
Centre for Cooperative Research on Alternative Energies (CIC energiGUNE), Basque Research and Technology Alliance (BRTA), Alava Technology Park, Albert Einstein 48, 01510 Vitoria-Gasteiz, Spain.
Molecules. 2024 Oct 4;29(19):4698. doi: 10.3390/molecules29194698.
Environmental impacts and resource availability are significant concerns for the future of lithium-ion batteries. This study focuses on developing novel fluorine-free electrolytes compatible with aqueous-processed cobalt-free cathode materials. The new electrolyte contains lithium 1,1,2,3,3-pentacyanopropenide (LiPCP) salt. After screening various organic carbonates, a mixture of 30:70 wt.% ethylene carbonate and dimethyl carbonate was chosen as the solvent. The optimal salt concentration, yielding the highest conductivity of 9.6 mS·cm at 20 °C, was 0.8 mol·kg. Vinylene carbonate was selected as a SEI-stabilizing additive, and the electrolyte demonstrated stability up to 4.4 V vs. Li+/Li. LiFePO and LiMnFePO were identified as suitable cobalt-free cathode materials. They were processed using sodium carboxymethyl cellulose as a binder and water as the solvent. Performance testing of various cathode compositions was conducted using cyclic voltammetry and galvanostatic cycling with the LiPCP-based electrolyte and a standard LiPF6-based one. The optimized cathode compositions, with an 87:10:3 ratio of active material to conductive additive to binder, showed good compatibility and performance with the new electrolyte. Aqueous-processed LiFePO and LiMnFePO achieved capacities of 160 mAh·g and 70 mAh·g at C/10 after 40 cycles, respectively. These findings represent the first stage of investigating LiPCP for the development of greener and more sustainable lithium-ion batteries.
环境影响和资源可用性是锂离子电池未来面临的重大问题。本研究重点在于开发与水相加工的无钴正极材料兼容的新型无氟电解质。新型电解质包含1,1,2,3,3 - 五氰基丙烯锂（LiPCP）盐。在筛选了各种有机碳酸酯后，选择了质量比为30:70的碳酸乙烯酯和碳酸二甲酯的混合物作为溶剂。在20°C下产生最高电导率9.6 mS·cm的最佳盐浓度为0.8 mol·kg。碳酸亚乙烯酯被选作一种稳定固体电解质界面的添加剂，该电解质在相对于Li⁺/Li高达4.4 V的电压下表现出稳定性。磷酸铁锂（LiFePO）和锰铁磷酸锂（LiMnFePO）被确定为合适的无钴正极材料。它们使用羧甲基纤维素钠作为粘合剂、水作为溶剂进行加工。使用基于LiPCP的电解质和标准的基于LiPF₆的电解质，通过循环伏安法和恒电流循环对各种正极组合物进行性能测试。活性材料、导电添加剂与粘合剂比例为87:10:3的优化正极组合物与新型电解质表现出良好的兼容性和性能。水相加工的LiFePO和LiMnFePO在40次循环后，在C/10倍率下分别实现了160 mAh·g和70 mAh·g的容量。这些发现代表了研究LiPCP以开发更绿色、更可持续锂离子电池的第一阶段。
