Stability of conductive carbon additives in 5?V-class Li-ion batteries
Stability of conductive carbon additives in 5?V-class Li-ion batteries
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5V级锂离子电池中导电碳添加剂的稳定性
DOI：
10.1016/j.carbon.2019.11.051
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发表时间：
2020
期刊：
影响因子：
10.9
通讯作者：
Yamada Atsuo
中科院分区：
文献类型：
--
作者：
Ko Seongjae;Yamada Yuki;Lander Laura;Yamada Atsuo
为了实现具有更高能量密度的高压(5V级)锂离子电池，电极组件，特别是导电碳添加剂的高氧化稳定性是至关重要的。在本工作中，通过分析乙炔黑在氧化稳定性高的高浓度电解液中高达5.5 V(vs.Li+/Li)的氧化反应产生的容量(即电量)，研究了乙炔黑的氧化稳定性。1200℃的热处理可以通过减少表面活性位的数量来提高其在4.8℃以下的氧化稳定性。然而，由于渐进石墨化引起的电化学阴离子插层，进一步提高热处理温度会显著降低在较高电位(>；4.8 nV)下的稳定性。这项工作建议，对于5V级电池，应优化导电碳添加剂，同时将表面活性中心和过度石墨化降至最低。
A high oxidation stability of electrode components, especially of conductive carbon additives, is of importance in order to realize high-voltage (5 V-class) Li-ion batteries with higher energy densities. In this work, the oxidation stability of acetylene blacks is studied by analyzing the capacity (i.e., quantity of electricity) arising from their oxidation reactionsviachronopotentiometry up to 5.5 V (vs. Li+/Li) in a highly concentrated electrolyte with high oxidation stability. Annealing at 1200 °C can improve their oxidation stability below 4.8 V by reducing the amounts of surface active sites. However, further raising the annealing temperature significantly degrades the stability at higher potentials (>4.8 V) due to the electrochemical anion intercalation induced by progressive graphitization. This work suggests that, for 5 V-class batteries, conductive carbon additives should be optimized to simultaneously minimize surface active sites and excessive graphitization.