Influence of Particle Morphologies of LiFePO4 on Water- and Solvent-Based Processing and Electrochemical Properties
Influence of Particle Morphologies of LiFePO4 on Water- and Solvent-Based Processing and Electrochemical Properties
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DOI：
10.3390/su9060888
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发表时间：
2017-06-01
期刊：
影响因子：
3.9
通讯作者：
Pettinger, Karl-Heinz
中科院分区：
文献类型：
--
作者：
Starke, Benjamin;Seidlmayer, Stefan;Pettinger, Karl-Heinz
LiFePO4（LFP）初级颗粒和次级团聚体已被加工成水基和溶剂基阴极。通过中子和X射线衍射，它被发现，没有结构变化的LiFePO4发生在水基和溶剂基浆料制备。电化学表征进行了全电池和颗粒形态的明显影响是可观察的。初级颗粒的水基加工导致电化学性能的缺陷，而次级附聚物在加工期间对水不敏感。在水的存在下，浆料制备期间的高机械应力导致碳涂层的部分脱离。然而，对于二次附聚物，这种影响可以忽略不计，因为只有表面颗粒暴露于机械应力。由于较长的扩散路径和二次团聚体在阴极中表现出微观不均匀性的事实，二次团聚体的C速率能力略低于一次颗粒的C速率能力。本文表明，对于任何高能量的应用与中等的C率，二次团聚体具有很大的潜力，环境友好和成本效益的水基阴极生产。
LiFePO4 (LFP) primary particles and secondary agglomerates have been processed into water-and solvent-based cathodes. By means of neutron and X-ray diffraction it was found that no structural changes of LiFePO4 occurred upon water-and solvent-based slurry preparation. Electrochemical characterization was carried out with full-cells and a distinct influence of particle morphology was observable. Water-based processing of primary particles leads to deficits in electrochemical performance while secondary agglomerates are non-sensitive to water during processing. In the presence of water, high mechanical stress during slurry preparation causes a partial detachment of carbon coating. However, this effect is negligible for secondary agglomerates since only surface particles are exposed to mechanical stress. Due to longer diffusion paths and the fact that secondary agglomerates represent a micro-heterogeneity in the cathode, the C-rate capability of secondary agglomerates is slightly lower than that of primary particles. This paper demonstrates that for any high energy application with moderate C-rates, secondary agglomerates hold a great potential for environmentally friendly and cost-efficient water-based cathode production.