A highly stable pre-lithiated SiO_x anode coated with a “salt-in-polymer” layer

Abstract

Micron-sized pre-lithiated SiOx (Li-MSiOx) anode materials have shown promises for building high-energy-density lithium-ion batteries due to their high theoretical capacity, high initial Coulombic efficiency and low cost. Nevertheless, the huge...

An Elastic Cross-Linked Binder for Silicon Anodes in Lithium-Ion Batteries with a High Mass Loading

“…The popularity of portable electronic products and electric vehicles around the world has led to a flourishing age of lithium-ion batteries (LIBs) over the last decades. , With ever-growing demand for longer duration and range, it is vital to develop advanced LIBs with a higher energy density. , To boost the energy density, applying novel materials with a high specific capacity is one of the most effective approaches. , For anode, silicon (Si) is considered as a promising candidate to replace the commercial graphite because of its ultrahigh theoretical capacity (3579 mAh g –1 , Li 3.75 Si), moderate operate potential (∼0.4 V vs Li/Li + ), and high earth reserves. − However, the mechanical stress caused by huge volume changes of Si (>300%) during cycling leads to active material shedding, electrode pulverization, and repeated formation of the solid electrolyte interphase (SEI) layer, resulting in rapid capacity fading. − To settle the above issues, several strategies based on nanoengineering and morphology design have been proposed, such as Si nanotubes, porous Si, and yolk–shell structure . Besides, doping and surface engineering are also fascinating, including lithium/boron co-doping, magnesium doping, and artificial SEI . Although these strategies can mitigate huge volume changes and improve the cycling performance of Si, the manufacturing process is usually complex and expensive.…”

“…16 Besides, doping and surface engineering are also fascinating, including lithium/boron co-doping, 17 magnesium doping, 18 and artificial SEI. 19 Although these strategies can mitigate huge volume changes and improve the cycling performance of Si, the manufacturing process is usually complex and expensive. Thus, there is still a lack of desirable approaches with industrial scalability and low cost to promote practical use of Si-based anodes.…”

Body Armor-Inspired Double-Wrapped Binder with High Energy Dispersion for a Stable SiOx Anode

“…To further promote the commercialization of SiO x anodes, numerous efforts have been devoted to designing ingenious nanostructures, tailoring the component in a solid electrolyte interface (SEI) layer , and exploring electrolyte additives. , Besides, developing a more advanced binder has also been deemed to be an auspicious strategy due to the merits of convenience, high efficiency, and cost-effectiveness. − As is well known, proper mechanical properties are crucial for a binder to maintain the cycling stability of Si-based anodes . It is widely accepted that a polymer binder’s intrinsic molecular configuration, and intramolecular and intermolecular interactions highly determine the mechanical property of the binder. , Generally, because of the intrinsic hard polymer backbone or covalent 3D network cross-linked configuration, a stiff binder is short of sufficient toughness to endure the structural damage caused by repeated volume change. , In comparison with the stiff binder, an elastic binder consisting of a soft polymer chain or flexible interaction could adapt to the huge volume expansion and contraction of SiO x particles .…”

“…To further promote the commercialization of SiO x anodes, numerous efforts have been devoted to designing ingenious nanostructures, tailoring the component in a solid electrolyte interface (SEI) layer 17,18 and exploring electrolyte additives. 19,20 Besides, developing a more advanced binder has also been deemed to be an auspicious strategy due to the merits of convenience, high efficiency, and cost-effectiveness.…”

Carboxymethyl Three-Dimensional Cross-Linked Biopolymer Binder for High-Performance Silicon Anodes in Lithium-Ion Batteries

“…Nanotechnology of silicon materials effectively avoids the cracking and pulverization of anode electrodes. Nanostructural silicon architectures reduce the particle size, which could shorten the ion transmission distance, reduce polarization, and release stress during the delithiation process. , But this small-size nanosilicon material results in large agglomeration, low compaction density, and high cost. , Another strategy to address the volume expansion issue is to fabricate interfacial confinement outside silicon particles, for instance, artificial SEI and carbon shells. − The internal void space endures the silicon volume expansion and deforming SEI film, while the carbon shell affords interfacial stability. However, an intricate preparation process and inadequate robust surface coating layer make these strategies impractical for silicon-based anodes of lithium-ion batteries. − Actually, a small proportion of binders plays a significant role in improving the cycle performance of silicon anodes to bind active materials, conductive agents, and current collectors together during continuous charge–discharge cycles.…”