In this work, based on First-principle plane wave pseudo-potential method, we have carried out an in-depth study on the possible dead lithium phase of Sn-Zn alloy as anode materials for lithium ion batteries. Through ...In this work, based on First-principle plane wave pseudo-potential method, we have carried out an in-depth study on the possible dead lithium phase of Sn-Zn alloy as anode materials for lithium ion batteries. Through investigation, we found that the phases LixSn4Zn4(x = 2, 4, 6, 8) contributed to re-versible capacity, while the phases LixSn4Zn8-(x-4)(x = 4.74, 7.72) led to capacity loss due to high forma-tion energy, namely, they were the dead lithium phases during the charge/discharge process. And we come up with a new idea that stable lithium alloy phase with high lithiation formation energy (dead lithium phase) can also result in high loss of active lithium ion, besides the traditional expression that the formation of solid electrolyte interface film leads to high capacity loss.展开更多
基金Supported by the National Natural Science Foundation of China (Grant No. 50771046)Natural Science Foundation of Guangdong Province (Grant No.05200534)+1 种基金Key Projects of Guangdong Province and Guangzhou City (Grant Nos. 2006A10704003 and 2006Z3-D2031)China Postdoctoral Science Foundation (Project No. 20080440764)
文摘In this work, based on First-principle plane wave pseudo-potential method, we have carried out an in-depth study on the possible dead lithium phase of Sn-Zn alloy as anode materials for lithium ion batteries. Through investigation, we found that the phases LixSn4Zn4(x = 2, 4, 6, 8) contributed to re-versible capacity, while the phases LixSn4Zn8-(x-4)(x = 4.74, 7.72) led to capacity loss due to high forma-tion energy, namely, they were the dead lithium phases during the charge/discharge process. And we come up with a new idea that stable lithium alloy phase with high lithiation formation energy (dead lithium phase) can also result in high loss of active lithium ion, besides the traditional expression that the formation of solid electrolyte interface film leads to high capacity loss.
