Laser induced molybdenum sulphide loading on doped graphene cathode for highly stable lithium sulphur battery

Richard Field,Qian Chen,Yudong Peng,Zhu Liu,Guangyu Zhu,Monika S. Walczak,Yihe Huang,Hu Zhao,Lin Li

doi:10.1038/s42004-019-0240-2

Richard Field, Qian Chen + Show 7 more

Open Access

https://doi.org/10.1038/s42004-019-0240-2

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Abstract

Lithium sulphur (Li-S) batteries are known to have much higher charge capacity than the currently widely used lithium-ion batteries with graphite anodes. However, maintaining high charge cycle stability is a key challenge for Li-S batteries due to the shuttle effect. Here we show highly stable characteristics with 100% charge capacity of Li-S batteries with 500 charge/discharge cycles at 0.5 C, 1 C, 2 C and 3 C charge rates. This was made possible by the combination of laser synthesised sulfur (S) and nitrogen (N) doped graphene electrodes (without a binder) with molybdenum sulphide (MoS2) nanoparticle loading. The N/S doped porous graphene structure presented enhanced interface adsorption by the production of –SO2, which suppressed diffusion of polysulfide into the electrolyte through promoting oxygen-containing functional groups chemically bonding with sulfur. A low electrolyte resistance, interphase contact resistance and charge-transfer resistance accelerate electrons and Li+ transport by laser induced N/S doped graphene.

Highlights

Lithium sulphur (Li-S) batteries are known to have much higher charge capacity than the currently widely used lithium-ion batteries with graphite anodes
Energy density of 550–600 Wh/kg is a target for practical Lithium sulfur (Li–S) batteries, which is
As the 355 nm UV laser wavelength has a photon energy of 3.49 eV, which is higher than the C–S bond energy (2.8 eV) from the dimethyl sulfoxide (DMSO) and the C–N bond energy (3.14 eV) of PBI, it would enable both photochemical and photothermal processes to occur when interacting with the PBI ink to enable customized sulfur and nitrogen doping at low laser powers and avoid thermal damages to the substrate[33,34,35]

Summary

Introduction

Lithium sulphur (Li-S) batteries are known to have much higher charge capacity than the currently widely used lithium-ion batteries with graphite anodes. As the current density increased from 0.1 to 1 C, the heteroatom doped porous graphene with nano-MoS2 implant electrode displayed recoverable and stable capacities from 1310 mAhg−1 for 0.1 C to 600 mAhg−1 for 1 C charge rate.

Results

Conclusion