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Silicon carbide-free graphene growth on silicon for lithium-ion battery with high volumetric energy density.

Son IH, Hwan Park J, Kwon S, Park S, Rümmeli MH, Bachmatiuk A, Song HJ, Ku J, Choi JW, Choi JM, Doo SG, Chang H - Nat Commun (2015)

Bottom Line: However, the large volume change of silicon over charge-discharge cycles weakens its competitiveness in the volumetric energy density and cycle life.Here we report direct graphene growth over silicon nanoparticles without silicon carbide formation.The graphene layers anchored onto the silicon surface accommodate the volume expansion of silicon via a sliding process between adjacent graphene layers.

View Article: PubMed Central - PubMed

Affiliation: Energy Material Lab, Material Research Center, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803, Republic of Korea.

ABSTRACT
Silicon is receiving discernable attention as an active material for next generation lithium-ion battery anodes because of its unparalleled gravimetric capacity. However, the large volume change of silicon over charge-discharge cycles weakens its competitiveness in the volumetric energy density and cycle life. Here we report direct graphene growth over silicon nanoparticles without silicon carbide formation. The graphene layers anchored onto the silicon surface accommodate the volume expansion of silicon via a sliding process between adjacent graphene layers. When paired with a commercial lithium cobalt oxide cathode, the silicon carbide-free graphene coating allows the full cell to reach volumetric energy densities of 972 and 700 Wh l(-1) at first and 200th cycle, respectively, 1.8 and 1.5 times higher than those of current commercial lithium-ion batteries. This observation suggests that two-dimensional layered structure of graphene and its silicon carbide-free integration with silicon can serve as a prototype in advancing silicon anodes to commercially viable technology.

No MeSH data available.


Related in: MedlinePlus

The volumetric energy density of 5 wt%-Gr–Si.(a) The volumetric capacities of pure Si film (calculation, cal.), theoretically packed Si NP film (calculation), 5 wt%-Si–Gr electrode (experimental) and graphite electrode (experimental). The value of theoretically packed Si NP film (calculation) was obtained by consideration of the gravimetric theoretical capacity of Si at room temperature (3,580 mAh g−1), the density of Si (2.2 g cm−3), the void portion in the theoretical particle packing (body centred, 0.32) and the binder content (∼20 wt%). (b) Cross-sectional SEM images of the 5 wt%-Gr–Si and commercial graphite electrodes (left). Top (right) and front (blue inset box) views of the 5 wt%-Gr–Si//LiCoO2 and graphite//LiCoO2 full cells with the same total energy (9.0 Wh). Both cells were wound into 18650 cylindrical cases with an identical winding tension. (c) The cycling performance of the 5 wt%-Si–Gr//LiCoO2 and graphite//LiCoO2 full cells. The 5 wt%-Gr–Si electrode in b and c is the one with 3.0 mAh cm−2 shown in Fig. 4c.
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f5: The volumetric energy density of 5 wt%-Gr–Si.(a) The volumetric capacities of pure Si film (calculation, cal.), theoretically packed Si NP film (calculation), 5 wt%-Si–Gr electrode (experimental) and graphite electrode (experimental). The value of theoretically packed Si NP film (calculation) was obtained by consideration of the gravimetric theoretical capacity of Si at room temperature (3,580 mAh g−1), the density of Si (2.2 g cm−3), the void portion in the theoretical particle packing (body centred, 0.32) and the binder content (∼20 wt%). (b) Cross-sectional SEM images of the 5 wt%-Gr–Si and commercial graphite electrodes (left). Top (right) and front (blue inset box) views of the 5 wt%-Gr–Si//LiCoO2 and graphite//LiCoO2 full cells with the same total energy (9.0 Wh). Both cells were wound into 18650 cylindrical cases with an identical winding tension. (c) The cycling performance of the 5 wt%-Si–Gr//LiCoO2 and graphite//LiCoO2 full cells. The 5 wt%-Gr–Si electrode in b and c is the one with 3.0 mAh cm−2 shown in Fig. 4c.

Mentions: The volumetric capacity of Gr–Si was elucidated in comparison with those of the theoretical and commercial cases (Fig. 5a). The volumetric capacity of 5 wt%-Gr–Si (for the electrode with 3.0 mAh cm−2 in Fig. 4c) ranges from 2,500 to 3,000 mAh cm−3, which is close to the theoretical value (4,284 mAh cm−3) of the pristine Si particles on the assumption of their ideal packing (details in figure caption). The present values are far higher than that (550 mAh cm−3) of the current commercial graphite-based anodes. To further assess the practical viability of 5 wt%-Gr–Si, full cell performance was examined by pairing with a commercial cathode, LiCoO2. By consideration of the average cell voltage of 3.5 V, the areal capacity of 3.0 mAh cm−2, and a total electrode thickness of 108 μm (electrode+separator+current collector, Gr–Si thickness=15 μm), the volumetric energy density of the present full cell reaches 972 Wh l−1. This value is remarkable since it is 1.8 times as large as that (550 Wh l−1) of widely used current commercial LIBs calculated based on the same metric( http://www.samsungsdi.com/lithium-ion-battery/overview).


Silicon carbide-free graphene growth on silicon for lithium-ion battery with high volumetric energy density.

Son IH, Hwan Park J, Kwon S, Park S, Rümmeli MH, Bachmatiuk A, Song HJ, Ku J, Choi JW, Choi JM, Doo SG, Chang H - Nat Commun (2015)

The volumetric energy density of 5 wt%-Gr–Si.(a) The volumetric capacities of pure Si film (calculation, cal.), theoretically packed Si NP film (calculation), 5 wt%-Si–Gr electrode (experimental) and graphite electrode (experimental). The value of theoretically packed Si NP film (calculation) was obtained by consideration of the gravimetric theoretical capacity of Si at room temperature (3,580 mAh g−1), the density of Si (2.2 g cm−3), the void portion in the theoretical particle packing (body centred, 0.32) and the binder content (∼20 wt%). (b) Cross-sectional SEM images of the 5 wt%-Gr–Si and commercial graphite electrodes (left). Top (right) and front (blue inset box) views of the 5 wt%-Gr–Si//LiCoO2 and graphite//LiCoO2 full cells with the same total energy (9.0 Wh). Both cells were wound into 18650 cylindrical cases with an identical winding tension. (c) The cycling performance of the 5 wt%-Si–Gr//LiCoO2 and graphite//LiCoO2 full cells. The 5 wt%-Gr–Si electrode in b and c is the one with 3.0 mAh cm−2 shown in Fig. 4c.
© Copyright Policy - open-access
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4491181&req=5

f5: The volumetric energy density of 5 wt%-Gr–Si.(a) The volumetric capacities of pure Si film (calculation, cal.), theoretically packed Si NP film (calculation), 5 wt%-Si–Gr electrode (experimental) and graphite electrode (experimental). The value of theoretically packed Si NP film (calculation) was obtained by consideration of the gravimetric theoretical capacity of Si at room temperature (3,580 mAh g−1), the density of Si (2.2 g cm−3), the void portion in the theoretical particle packing (body centred, 0.32) and the binder content (∼20 wt%). (b) Cross-sectional SEM images of the 5 wt%-Gr–Si and commercial graphite electrodes (left). Top (right) and front (blue inset box) views of the 5 wt%-Gr–Si//LiCoO2 and graphite//LiCoO2 full cells with the same total energy (9.0 Wh). Both cells were wound into 18650 cylindrical cases with an identical winding tension. (c) The cycling performance of the 5 wt%-Si–Gr//LiCoO2 and graphite//LiCoO2 full cells. The 5 wt%-Gr–Si electrode in b and c is the one with 3.0 mAh cm−2 shown in Fig. 4c.
Mentions: The volumetric capacity of Gr–Si was elucidated in comparison with those of the theoretical and commercial cases (Fig. 5a). The volumetric capacity of 5 wt%-Gr–Si (for the electrode with 3.0 mAh cm−2 in Fig. 4c) ranges from 2,500 to 3,000 mAh cm−3, which is close to the theoretical value (4,284 mAh cm−3) of the pristine Si particles on the assumption of their ideal packing (details in figure caption). The present values are far higher than that (550 mAh cm−3) of the current commercial graphite-based anodes. To further assess the practical viability of 5 wt%-Gr–Si, full cell performance was examined by pairing with a commercial cathode, LiCoO2. By consideration of the average cell voltage of 3.5 V, the areal capacity of 3.0 mAh cm−2, and a total electrode thickness of 108 μm (electrode+separator+current collector, Gr–Si thickness=15 μm), the volumetric energy density of the present full cell reaches 972 Wh l−1. This value is remarkable since it is 1.8 times as large as that (550 Wh l−1) of widely used current commercial LIBs calculated based on the same metric( http://www.samsungsdi.com/lithium-ion-battery/overview).

Bottom Line: However, the large volume change of silicon over charge-discharge cycles weakens its competitiveness in the volumetric energy density and cycle life.Here we report direct graphene growth over silicon nanoparticles without silicon carbide formation.The graphene layers anchored onto the silicon surface accommodate the volume expansion of silicon via a sliding process between adjacent graphene layers.

View Article: PubMed Central - PubMed

Affiliation: Energy Material Lab, Material Research Center, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803, Republic of Korea.

ABSTRACT
Silicon is receiving discernable attention as an active material for next generation lithium-ion battery anodes because of its unparalleled gravimetric capacity. However, the large volume change of silicon over charge-discharge cycles weakens its competitiveness in the volumetric energy density and cycle life. Here we report direct graphene growth over silicon nanoparticles without silicon carbide formation. The graphene layers anchored onto the silicon surface accommodate the volume expansion of silicon via a sliding process between adjacent graphene layers. When paired with a commercial lithium cobalt oxide cathode, the silicon carbide-free graphene coating allows the full cell to reach volumetric energy densities of 972 and 700 Wh l(-1) at first and 200th cycle, respectively, 1.8 and 1.5 times higher than those of current commercial lithium-ion batteries. This observation suggests that two-dimensional layered structure of graphene and its silicon carbide-free integration with silicon can serve as a prototype in advancing silicon anodes to commercially viable technology.

No MeSH data available.


Related in: MedlinePlus