Layer-by-Layer Deposition of Organic–Inorganic Hybrid Multilayer on Microporous Polyethylene Separator to Enhance the Electrochemical Performance of Lithium-Ion Battery

Abstract

A simple layer-by-layer (LbL) self-assembly process of poly(acrylic acid) (PAA) and ZrO2 was applied to construct functional ultrathin multilayers on polyethylene (PE) separators without sacrificing the excellent porous structure of separators. Such PAA/ZrO2 LbL-modified PE separators possess good electrolyte wettability, excellent electrolyte uptake, high ionic conductivity and large Li(+) transference number. More importantly, the top layer of LbL self-assembly would affect the dissociation of electrolyte and the formation of solid electrolyte interphase (SEI) layer in half-cells. Compared with the pristine and (PAA/ZrO2)1PAA-modified PE separators, (PAA/ZrO2)3-modified PE separator shows a larger Li(+) transference number (0.6) and a faster tendency to form a stable SEI layer, endowing half-cells with excellent capacity retention at high C-rates and superior cycling performance. These fascinating characteristics will provide the LbL self-assembly with a promising method to improve the surface property of PE separators for high performance lithium-ion batteries.

Advanced Separators for Lithium‐Ion and Lithium–Sulfur Batteries: A Review of Recent Progress

“…A ZrO 2 /poly(acrylic acid) (PAA) coating was assembled onto a plasma‐activated PE separator through a layer‐by‐layer process . The ZrO 2 /PAA coating was crosslinked with the PE substrate by carbodiimide crosslinking.…”

Functional metal–organic framework boosting lithium metal anode performance via chemical interactions

“…In the literature there have been reports on modified separators that induce increased Li + transference numbers. 56–58 Amine groups are regarded as strongly interactive with ions, thereby facilitating dissociation of ion pairs and promoting Li + transport. 58,59 However, the exact interaction mechanism has still yet to be revealed.…”

Magnesium Borate Fiber Coating Separators with High Lithium‐Ion Transference Number for Lithium‐Ion Batteries

“…[18] For example, Wang et al deposited ZrO 2 with Lewis acid sites onto the separator to absorb Lewis base species in the electrolyte, PF À 6 and increase t Li + by electrostatic interaction. [12,19] The ZSM-5 molecular sieve with amounts of Lewis acid sites based on SiÀ O and AlÀ O backbones was also used as the coating layer on the separator to absorb PF À 6 thus the t Li + increases from 0.28 to 0.44. [11] In addition, it has been reported that electron-deficient functional group such as boron atoms in the borate ester polymers can also adsorb anions to increase the t Li + .…”