| 1. |
- Jiao, Xingxing, et al.
(författare)
-
Highly Energy-Dissipative, Fast Self-Healing Binder for Stable Si Anode in Lithium-Ion Batteries
- 2021
-
Ingår i: Advanced Functional Materials. - : Wiley. - 1616-3028 .- 1616-301X. ; 31:3
-
Tidskriftsartikel (refereegranskat)abstract
- A double-wrapped binder has been rationally designed with high Young's modulus polyacrylic acid (PAA) inside and low Young's modulus bifunctional polyurethane (BFPU) outside to address the large inner stress of silicon anode with drastic volume changes during cycling. Harnessing the "hard to soft" gradient distribution strategy, the rigid PAA acts as a protective layer to dissipate the inner stress first during lithiation, while the elastic binder BFPU serves as a buffer layer to disperse residual stress, and thus avoids structural damage of rigid PAA. Moreover, the introduction of BFPU with fast self-healing ability can dynamically recover the microcracks arising from large stress, further ensuring the integrity of silicon anode. This multifunctional binder with smart design of double-wrapped structure provides enlightenment on enlarging the cycling life of high-energy-density lithium-ion batteries that suffer enormous volume change during the cycling process.
|
|
| 2. |
- Liu, Yangyang, et al.
(författare)
-
Insight into the Critical Role of Exchange Current Density on Electrodeposition Behavior of Lithium Metal
- 2021
-
Ingår i: Advanced Science. - : Wiley. - 2198-3844 .- 2198-3844. ; 8:5
-
Tidskriftsartikel (refereegranskat)abstract
- Due to an ultrahigh theoretical specific capacity of 3860 mAh g−1, lithium (Li) is regarded as the ultimate anode for high-energy-density batteries. However, the practical application of Li metal anode is hindered by safety concerns and low Coulombic efficiency both of which are resulted fromunavoidable dendrite growth during electrodeposition. This study focuses on a critical parameter for electrodeposition, the exchange current density, which has attracted only little attention in research on Li metal batteries. A phase-field model is presented to show the effect of exchange current density on electrodeposition behavior of Li. The results show that a uniform distribution of cathodic current density, hence uniform electrodeposition, on electrode is obtained with lower exchange current density. Furthermore, it is demonstrated that lower exchange current density contributes to form a larger critical radius of nucleation in the initial electrocrystallization that results in a dense deposition of Li, which is a foundation for improved Coulombic efficiency and dendrite-free morphology. The findings not only pave the way to practical rechargeable Li metal batteries but can also be translated to the design of stable metal anodes, e.g., for sodium (Na), magnesium (Mg), and zinc (Zn) batteries.
|
|
