Toward Practical High‐Energy Batteries: A Modular‐Assembled Oval‐Like Carbon Microstructure for Thick Sulfur Electrodes

Abstract

The modular assembly of microstructures from simple nanoparticles offers a powerful strategy for creating materials with new functionalities. Such microstructures have unique physicochemical properties originating from confinement effects. Here, the modular assembly of scattered ketjen black nanoparticles into an oval-like microstructure via double "Fischer esterification," which is a form of surface engineering used to fine-tune the materials surface characteristics, is presented. After carbonization, the oval-like carbon microstructure shows promise as a candidate sulfur host for the fabrication of thick sulfur electrodes. Indeed, a specific discharge capacity of 8.417 mAh cm at 0.1 C with a high sulfur loading of 8.9 mg cm is obtained. The large-scale production of advanced lithium-sulfur battery pouch cells with an energy density of 460.08 Wh kg @18.6 Ah is also reported. This work provides a radically different approach for tuning the performance of a variety of surfaces for energy storage materials and biological applications by reconfiguring nanoparticles into desired structures.

Recent progress on biomass‐derived ecomaterials toward advanced rechargeable lithium batteries

“…The randomly distributed pores without interconnected and perforative structure give rise to a long ion diffusion distance or decreased ion transport channel, which lead to high ion migration resistance . Especially in electrodes with high loading, this adverse effect will be amplified owing to the higher response to ion transportation . Therefore, the oriented design of interconnected architecture with low tortuosity electrode should be strongly encouraged.…”

Structural Design of Lithium–Sulfur Batteries: From Fundamental Research to Practical Application

“…The assembled Li-S soft package delivered a high capacity of 18.6 Ah and an average voltage of 2.05 V with a low E/S ratio of 2.7. Furthermore, the soft package can run steadily for 7 cycles with a high practical energy density of 460 W h kg −1 [165]. Recently, as shown in Fig.…”

“…One of the most popular strategies to utilize nanocarbon is the integration of primary nanoparticles into microsized secondary structures [22, [164][165][166][167]. As shown in Fig.…”

“…Reprinted with permission from Ref. [165], copyright 2017, Wiley-VCH. f The photograph of 550 W h kg −1 Li-S rechargeable soft package [349].…”

“…Recently, Chen et al [165] designed an oval-like microstructures (OLCMs) via assembling the KB nanoparticles into microstructure on the basis of a double "Fischer esterification" mechanism. Benefiting from the "omnidirectional" and isotropic electron transportation and internal pinholes, which facilitate the electron transfer and Li + diffusion, the batteries assembled with a high sulfur loading of 8.9 mg cm −2 sulfur-loaded OLCMs could deliver a high areal capacity of 8.417 mA h cm −2 at 0.1 C. Furthermore, the large-scale production of advanced lithium-sulfur battery pouch cells with an energy density of 460.08 W h kg −1 @18.6 Ah were also observed to operate for seven cycles.…”