Lithium dendrite formation

The addition of some metal ions, such as Mg2+,Zn2+, In3+,orGa3+, and some organic additives, such as 2-thiophene, 2-methylfuran, or benzene, to propylene carbonate-LiC104 improved the coulombic efficiency for lithium cycling [112]. Lithium deposition on a lithium surface covered with a chemically stable, thin and tight layer which was formed by the addition of HF to electrolyte can suppress the lithium dendrite formation in secondary lithium batteries [113]. 

The simulated short-circuit test was developed to characterize the response of the separator to a short circuit without the complications of battery electrodes. The separator was spirally wound between lithium foils and placed in an AA-size can. To avoid lithium dendrite formation, an alternating voltage was applied to the cell. The cell current and can temperature were monitored. Figure 6 shows the behavior of Celgard membranes. 

In lithium rechargeable batteries carbon materials are used that function as a lithium reservoir at the negative electrode. Reversible intercalation, or insertion, of lithium into the carbon host lattice avoids the problem of lithium dendrite formation and provides a large improvement in terms of cycleability and safety (111). 

According to the measurement of differential scanning calorimeter (DSC), exothermic reaction of polymer electrolytes with lithium metal is lower compared with the liquid electrolyte. Polymer electrolytes also are effective for preventing lithium dendrite formation. This fact means that lithium metal can be used as the negative electrode by using polymer electrolytes. Furthermore, the polymer electrolyte is expected to function as separator because it has the sufficient high mechanical strength. 

CO2 should also be removed from the air and a lithium dendrite formation-free interlayer or an alternative lithium electrode, such as Li44Si [74], should be developed. 

Liu S, Imanishi N, Zhang T, Hirano A, Takeda Y, Yamamoto O, Yang J (2010) Lithium dendrite formation in Li/polyethylene oxide-lithium bis(trifluoromethanesulfonyl)imide and N-methy-N-propylpiperidinum bis(trifluoromethanesulfonyl)imide/Li cells. J Electrochem Soc 157 A1092... 

In lithium and lithium-ion batteries, several types of lithium intercalation materials are investigated. The most efficient anode material would be lithium metal, which shows by far the highest energy density, theoretically 3860 mAh-g. However, its main problems are the poor cyclability and safety problems due to lithium dendrite formation on the surface [304-306]. Metallic lithium dendrites can grow toward the cathodic side, which causes a short circuit in the cell, a drastic increase in temperature, uncontrolled reactions, and cell destruction. 

Tatsuma T, Taguchi M, Oyama N (2001) Inhibition effect of covalently cross-linked gel electrolytes on lithium dendrite formation. Electrochim Acta 46(8) 1201-1205, http //dx.doi. org/10.1016/S0013-4686(00)00706-4... 

The other negative electrode materials mainly include Al-based alloys, Pb-based alloys, and its oxides. Of course, Li metal can also be used as a negative electrode. However, the lithium metal rechargeable battery will not be discussed here, although great progress has been made, especially with the inhibition of lithium dendrite formation. 

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