Electrochemical and in situ x-ray diffraction studies of the reaction of lithium with tin oxide composites
Electrochemical and in situ x-ray diffraction studies of the reaction of lithium with tin oxide composites
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DOI：
10.1149/1.1837740
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发表时间：
1997-06-01
影响因子：
3.9
通讯作者：
Dahn, JR
中科院分区：
文献类型：
--
作者：
Courtney, IA;Dahn, JR
我们报道了各种氧化锡基化合物的电化学和原位x射线衍射实验；在可充电锂离子硬币电池中，作为相对于锂金属的阴极的SnO， SnO3， LiSnO3和SnSiO3玻璃。这些材料的放电容量约为1000 mAh/(g Sn)，符合每Sn原子4.4 Li原子或991 mAh/(g Sn)的合金容量限制。这些材料还显示出显著的不可逆容量，范围从200 mAh/（g活性）到700 mAh/（g活性）。对这些材料进行的原位x射线衍射实验表明，通过引入锂，首先形成氧化锂和锡，然后形成各种Li-Sn合金相。当锂被移除时，原始材料不会重新形成。最后的成分是金属锡，可能与无定形氧化锂混合。原料中氧化锡中的氧与锂不可逆结合，形成无定形的Li2O基质。锂锡合金化过程是完全可逆的；也许是由于这种锂“基质”的形成，它有助于保持电极颗粒的机械连接在一起。
We report our electrochemical and in situ x-ray diffraction experiments on a variety of tin oxide based compounds; SnO, SnO3, LiSnO3, and SnSiO3 glass, as cathodes opposite lithium metal in a rechargeable Li-ion coin cell. These materials, demonstrate discharge capacities on the order of 1000 mAh/(g Sn), which is consistent with the alloying capacity limit of 4.4 Li atoms per Sn atom, or 991 mAh/(g Sn). These materials also demonstrate significant irreversible capacities ranging from 200 mAh/(g active) to 700 mAh/(g active). In situ x-ray diffraction experiments on these materials show that by introducing lithium, lithium oxide and tin form first, which is then followed by the formation of the various Li-Sn alloy phases. When lithium is removed the original material does not reform. The ending composition is metallic tin, presumably mixed with amorphous lithium oxide. The oxygen from the tin oxide in the starting material bonds irreversibly with lithium to form an amorphous Li2O matrix. The Li-Sn alloying process is quite reversible; perhaps due to the formation of this lithia ''matrix'' which helps to keep the electrode particles mechanically connected together.