Rate capability of graphite materials as negative electrodes in lithium-ion capacitors

Sivakkumar, S. R.; Nerkar, Jawajar; Pandolfo, Anthony

doi:10.1016/j.electacta.2010.01.059

Cited by 288 publications

(189 citation statements)

References 27 publications

Supporting

Mentioning

172

Contrasting

Unclassified

Order By: Relevance

“…Thus, more significant capacity loss in some graphite samples at high C-rate could indicate greater polarization due to a thicker and more resistive SEI layer. 41 EIS measurements were also conducted on anodes both after formation and aging cycles to evaluate the impedance growth (Figure 4). Note that the impedance obtained from each graphite after aging cycles was much smaller than that of the corresponding cathode ( Figure S6b), further proving that the cathode is the main contributor to the full cell impedance after the aging cycles.…”

Section: Resultsmentioning

confidence: 99%

Selecting the Best Graphite for Long-Life, High-Energy Li-Ion Batteries

Mao

Wood

David

et al. 2018

J. Electrochem. Soc.

View full text Add to dashboard Cite

Most lithium-ion batteries still rely on intercalation-type graphite materials for anodes, so it is important to consider their role in full cells for applications in electric vehicles. Here, we systematically evaluate the chemical and physical properties of six commerciallyavailable natural and synthetic graphites to establish which factors have the greatest impact on the cycling stability of full cells with nickel-rich LiNi0.8Mn0.1Co0.1O2 (NMC811) cathodes. Electrochemical data and post-mortem characterization explain the origin of capacity fade. The NMC811 cathode shows large irreversible capacity loss and impedance growth, accounting for much of full cell degradation. However, six graphite anodes demonstrate significant differences with respect to structural change, surface area, impedance growth, and SEI chemistry, which impact overall capacity retention. We found long cycle life correlated most strongly with stable graphite crystallite size. In addition, graphites with lower surface area generally had higher coulombic efficiencies during formation cycles, which led to more stable long-term cycling. The best graphite screened here enables a capacity retention around 90% in full pouch cells over extensive long-term cycling compared to only 82% for cells with the lowest performing graphite. The results show that optimal graphite selection improves cycling stability of high energy lithium-ion cells. With the booming demands for electric vehicles and electronic devices, high energy density lithium-ion batteries with long cycle life are highly desired. Despite the recent progress in Si 1 and Li metal 2 as future anode materials, graphite still remains the active material of choice for the negative electrode. 3,4 Lithium ions can be intercalated into graphite sheets at various stages like Li x C 12 and Li x C 6 , providing a high specific capacity of 372 mAh/g (∼2.5 times higher than LiCoO 2 ) and high volumetric capacity (similar to LiCoO 2 ) corresponding to LiC 6 . 5,6 In addition to its low cost and non-toxicity, graphite has a lowest average voltage (150 mV vs. Li/Li + ) and the flat voltage profile, rendering a high overall cell voltage. 7 Graphite also displays a very low voltage hysteresis, which in turn results in high energy efficiency. 8 For applications in lithium-ion batteries, many properties of the graphite powders must be optimized including crystallinity, particle size, morphology, and surface chemistry. However, most research effort has been placed on the development and characterization of high performance cathodes, while the impact of the graphite anode on full cell performance has been largely unexplored.Compared to widely used battery cathodes such as LiCoO 2 (140 mAh/g), LiFePO 4 (160 mAh/g), LiNi 1/3 Mn 1/3 Co 1/3 O 2 (160 mAh/g), and LiNi 0.5 Mn 0.3 Co 0.2 O 2 (175 mAh/g), 9-11 nickel-rich LiNi 0.8 Mn 0.1 Co 0.1 O 2 (NMC811) is delivers a higher specific capacity (180-220 mAh/g), which increases the battery life on a single charge. 12,13 The high capacity arises because Ni is the main red...

show abstract

Section: Resultsmentioning

confidence: 99%

Selecting the Best Graphite for Long-Life, High-Energy Li-Ion Batteries

Mao

Wood

David

et al. 2018

J. Electrochem. Soc.

View full text Add to dashboard Cite

show abstract

“…[1][2][3] In line with this ongoing global effort, various hybrid devices of rechargeable battery and supercapacitor are becoming a particular interest of many researchers around the world. [3][4][5][6][7][8][9][10] Although having the same or similar research objectives and methodology, i.e., combination of the technical merits of supercapacitor (high power density and long cycle life) and rechargeable battery (high energy density), the current literature lacks clearly a generic and logical term for these hybrid devices. Very different names have been used, such as "redox capacitor", "pseudocapacitor", "Li-ion capacitor", "Na-ion capacitor", "hybrid electrochemical capacitor" and "hybrid supercapacitor".…”

Section: Introductionmentioning

confidence: 99%

“…Very different names have been used, such as "redox capacitor", "pseudocapacitor", "Li-ion capacitor", "Na-ion capacitor", "hybrid electrochemical capacitor" and "hybrid supercapacitor". [5][6][7][8][9][10] However, there is a particular concern on the latter four hybrid devices which are, strictly speaking, no longer capacitor or supercapacitor because their charge storage mechanisms are partly the same as that in a rechargeable battery. This situation in the current literature is not helpful to focus the diverse research interests on materials designs, synthesis and characterizations.…”

Section: Introductionmentioning

confidence: 99%

Fundamental Consideration for Electrochemical Engineering of Supercapattery

Akinwolemiwa¹

2018

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

Supercapattery is the generic name for various electrochemical energy storage (EES) devices combining the merits of battery (high energy density) and supercapacitor (high power density and long cycling life). In this article, the principle and applications of EES devices are selectively reviewed as the background for supercapattery development. The focus is on the engineering aspects for fabrication of two types of supercapattery: (i) by coupling a battery electrode with a supercapacitor electrode, or (ii) from materials that possess both the Nernstian and capacitive charge storage capacities. Fundamental rationales are discussed in relation with the designs, such as why the device is always asymmetrical, and what materials are suitable for making supercapattery. Whilst the key is how to optimize device performance in terms of energy capacity, power capability and cycle life, cost is also discussed on resource rich materials such as nanostructured composites and redox electrolytes.

show abstract

“…They are being both utilized and considered for numerous power source applications, such as auxiliary power sources for hybrid electric vehicles and short term power sources for mobile electronic devices [1][2][3]. Recently, electrochemically active materials and metal oxides, such as Sn, Si, cobalt oxide (Co 3 O 4 ), have attracted much attention as materials for supercapacitors.…”

Section: Introductionmentioning

confidence: 99%

Preparation and capacitance behaviors of cobalt oxide/graphene composites

Park¹,

Kim²

2012

Carbon letters

View full text Add to dashboard Cite

In this study, cobalt oxide (Co 3 O 4 )/graphene composites were synthesized through a simple chemical method at various calcination temperatures. We controlled the crystallinity, particle size and morphology of cobalt oxide on graphene materials by changing the annealing temperatures (200, 300, 400 o C). The nanostructured Co 3 O 4 /graphene hybrid materials were studied to measure the electrochemical performance through cyclic voltammetry. The Co 3 O 4 /graphene sample obtained at 200 o C showed the highest capacitance of 396 Fg -1 at 5 mVs -1 . The morphological structures of composites were also examined by scanning electron microscopy and transmission electron microscopy (TEM). Annealing Co 3 O 4 /graphene samples in air at different temperatures significantly changed the morphology of the composites. The flower-like cobalt oxides with higher crystallinity and larger particle size were generated on graphene according to the increase of calcination temperature. A TEM analysis of the composites at 200 o C revealed that nanoscale Co 3 O 4 (~7 nm) particles were deposited on the surface of the graphene. The improved electrochemical performance was attributed to a combination effect of graphene and pseudocapacitive effect of Co 3 O 4 .

show abstract

Rate capability of graphite materials as negative electrodes in lithium-ion capacitors

Cited by 288 publications

References 27 publications

Selecting the Best Graphite for Long-Life, High-Energy Li-Ion Batteries

Selecting the Best Graphite for Long-Life, High-Energy Li-Ion Batteries

Fundamental Consideration for Electrochemical Engineering of Supercapattery

Preparation and capacitance behaviors of cobalt oxide/graphene composites

Contact Info

Product

Resources

About