Novel hard carbon/graphite composites synthesized by a facile<i>in situ</i>anchoring method as high-performance anodes for lithium-ion batteries

Ge, Chuanzhang; Fan, Zhenghua; Zhang, Jie; Qiao, Yu; Wang, Jianming; Ling, Licheng

doi:10.1039/c8ra07170e

Cited by 38 publications

(21 citation statements)

References 39 publications

(42 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As such, Yang et al proposed charging the battery at ∼60 °C and discharging at ambient temperature, finding that a high energy pouch cell (209 Wh kg −1 , Gr/NMC532) could retain 91.7 % of capacity after 2,500 cycles at a 10 min charging rate. In addition, chemical heteroatom doping and physical hybridizing with other anode materials that have higher lithiation potentials or better rate capability compared with the pristine graphite, such as hard carbon, amorphous Si, and SiO, are shown to some extent to alleviate Li plating.…”

Section: Challenges and Strategiesmentioning

confidence: 99%

Challenges and Strategies for Fast Charge of Li‐Ion Batteries

Zhang

2020

ChemElectroChem

View full text Add to dashboard Cite

Long charging time for Li‐ion batteries is a critical obstacle for the widespread adoption of electric vehicles, especially when compared with the rapid refueling of traditional internal combustion engine vehicles. Fast charging results in accelerated performance degradation and low energy efficiency for Li‐ion batteries. The batteries adopted in the present electric vehicle market are mainly based on chemistry consisting of a graphite anode and a layered lithium transition‐metal oxide cathode. The fast‐charging capability of such batteries is limited by Li plating on the graphite anode and structural instability of the layered lithium transition‐metal oxide cathode. In this Minireview, the challenges and possible solutions to these fast charge problems are reviewed at both the materials and cell levels.

show abstract

Section: Challenges and Strategiesmentioning

confidence: 99%

Challenges and Strategies for Fast Charge of Li‐Ion Batteries

Zhang

2020

ChemElectroChem

View full text Add to dashboard Cite

show abstract

“…[ 22–24 ] To improve its electrochemical performance, surface modification such as carbon coating is essential for NG to form a stable solid electrolyte interface (SEI) layer, which can reduce the initial irreversible capacity, enhance the cyclability, and improve the low‐temperature as well as thermal stability. [ 25 ] Besides, the NG can be hybridized with other carbon materials, including carbon nanotube (CNT), [ 26–28 ] carbon nanofiber (CNF), [ 29,30 ] and hard carbon [ 31 ] to further enhance the transport of electrons and Li + , leading to obvious improvements of cyclic stability and rate performance.…”

Section: Introductionmentioning

confidence: 99%

Revisiting the Roles of Natural Graphite in Ongoing Lithium‐Ion Batteries

et al. 2022

View full text Add to dashboard Cite

namely natural graphite (NG) and artificial graphite. NG originates from organics rich in carbon under long-term hightemperature and high-pressure geological environments, while artificial graphite is obtained by artificial carbonization and graphitization of organics under high temperature. The main types of NG include flake graphite (FG) and microcrystalline graphite (MG). NG, such as flake FG, delivers high capacity owing to its larger anisotropic crystalline domains, while the artificial graphite with higher purity and larger fraction of edge planes caused by smaller crystalline size presents excellent electrochemical kinetics, long cycle life, but low initial Coulombic efficiency (ICE). [9,10] NG has drawn great attention as anode material in LIBs due to the outstanding features such as high energy density, excellent processability, and low cost. [11,12] By 2020, NG accounted for 39% of the anode material market compared with 58% of artificial graphite. [13] It should be noted that the market share of NG will continue to grow due to the requirements for reducing CO 2 emission and environmental footprint since the production of artificial graphite is energy-intensive, high cost, and time consuming. [14] China is rich in resources of NG and is the world's largest exporter of NG. [15] FG shows a typical layered and anisotropic structure in which large graphite crystals stack together within orientation. [16] When used as an anode material, FG presents high specific capacity and ICE, but poor cyclic stability due to the structure destruction caused by volume expansion. [17,18] MG presents isotropic structure, consisting of graphitic microcrystals randomly stacked together. The MG anode presents better cyclic stability and outstanding rate performance due to the small volume expansion and shortened lithium ion (Li + ) diffusion distance, but low ICE owing to the large surface area. [16] It should be noted that our group invented NG-based materials as early as 1992, [19][20][21] and introduced such low-cost materials in many aspects of applications, and finally into LIBs as commercial anodes in 1997. [22][23][24] To improve its electrochemical performance, surface modification such as carbon coating is essential for NG to form a stable solid electrolyte interface (SEI) layer, which can reduce the initial irreversible capacity, enhance the cyclability, and improve the low-temperature as well as thermal stability. [25] Besides, the NG can be hybridized with other carbon materials, including carbon nanotube (CNT), [26][27][28] Graphite, commonly including artificial graphite and natural graphite (NG), possesses a relatively high theoretical capacity of 372 mA h g -1 and appropriate lithiation/de-lithiation potential, and has been extensively used as the anode of lithium-ion batteries (LIBs). With the requirements of reducing CO 2 emission to achieve carbon neutral, the market share of NG anode will continue to grow due to its excellent processability and low production energy consumption. NG, which is abundant in Chi...

show abstract

“…Previous studies on the concept of graphite/hard carbon hybrid anodes have been largely limited to surface modifications of the active materials prior to electrode fabrication, such as coating hard carbon onto graphite particle surfaces to improve rate capability [ 33,34 ] or applying graphite micro‐crystallites onto hard carbon particles to improve ICE and reversible capacity. [ 35 ] While mixing of varying carbonaceous materials have been studied for battery systems, [ 36–38 ] the charge rates in these studies have not addressed the DOE and industry fast‐charge targets (10 min charging time).…”

Section: Introductionmentioning

confidence: 99%

Enabling 6C Fast Charging of Li‐Ion Batteries with Graphite/Hard Carbon Hybrid Anodes

Chen

Goel

Namkoong

et al. 2020

Advanced Energy Materials

152

120

View full text Add to dashboard Cite

Li‐ion batteries that can simultaneously achieve high‐energy density and fast charging are essential for electric vehicles. Graphite anodes enable a high‐energy density, but suffer from an inhomogeneous reaction current and irreversible Li plating during fast charging. In contrast, hard carbon exhibits superior rate performance but lower energy density owing to its lower initial coulombic efficiency and higher average voltage. In this work, these tradeoffs are overcome by fabricating hybrid anodes with uniform mixtures of graphite and hard carbon, using industrially‐relevant multi‐layer pouch cells (>1 Ah) and electrode loadings (3 mAh cm−2). By controlling the graphite/hard carbon ratio, this study shows that battery performance can be systematically tuned to achieve both high‐energy density and efficient fast charging. Pouch cells with optimized hybrid anodes retain 87% and 82% of their initial specific energy after 500 cycles of 4C and 6C fast‐charge cycling, respectively. This is significantly higher than the 61% and 48% specific energy retention with graphite anodes under the same conditions. The enhanced performance is attributed to improved homogeneity of the reaction current throughout the hybrid anode, which is supported by continuum‐scale modeling. This process is directly compatible with existing roll‐to‐roll battery manufacturing, representing a scalable pathway to fast charging.

show abstract

Novel hard carbon/graphite composites synthesized by a facilein situanchoring method as high-performance anodes for lithium-ion batteries

Abstract: A facile in situ surface anchoring process is proposed for the fabrication of novel hard carbon/graphite composites. Such unique composites can be used as promising anodes for lithium-ion batteries with high performance.

Cited by 38 publications

References 39 publications

Challenges and Strategies for Fast Charge of Li‐Ion Batteries

Challenges and Strategies for Fast Charge of Li‐Ion Batteries

Revisiting the Roles of Natural Graphite in Ongoing Lithium‐Ion Batteries

Enabling 6C Fast Charging of Li‐Ion Batteries with Graphite/Hard Carbon Hybrid Anodes

Contact Info

Product

Resources

About