用于钾基能源存储的石墨材料研究进展

WANG Deng-ke; ZHANG Jia-peng; DONG Yue; CAO Bin; LI Ang; CHEN Xiao-hong; YANG Ru; SONG Huai-he

doi:10.1016/S1872-5805(21)60039-2

用于钾基能源存储的石墨材料研究进展

doi: 10.1016/S1872-5805(21)60039-2

北京化工大学化工资源有效利用国家重点实验室，材料电化学过程与技术北京市重点实验室，北京 100029

基金项目: 国家自然科学基金项目(U1610252)

详细信息

通讯作者:
宋怀河，教授. E-mail：songhh@mail.buct.edu.cn

中图分类号: TQ127.1⁺1
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出版历程
- 收稿日期: 2021-03-30
- 修回日期: 2021-04-28
- 网络出版日期: 2021-05-06
- 刊出日期: 2021-06-01

Progress on graphitic carbon materials for potassium-based energy storage

State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Electrochemical Process and Technology for Materials, Beijing University of Chemical Technology, Beijing 100029, China

More Information

Author Bio:
王登科，博士研究生. E-mail：1185767646@qq.com

Corresponding author: SONG Huai-he, Professor. E-mail: songhh@mail.buct.edu.cn

摘要

摘要: 由于钾离子电池成本低和其电化学性能与锂离子电池相当，钾离子电池和钾基双离子电池成为非常有潜力的新兴储能器件。另外，石墨作为已成功商业化应用的锂离子电池负极材料，也可容纳半径较大的钾离子和一些阴离子的插层并表现出较高的理论容量。但是，石墨材料在钾基能源存储器件中的应用依然面临一些挑战，如半径较大的离子插层会造成较大的体积膨胀（K⁺>61%；阴离子>130%），导致在循环过程中石墨层间滑移，电池容量衰减；同时由于石墨材料有限的层间距，半径较大的离子会表现出缓慢的插层反应动力学而导致较差的倍率性能。因此，针对存在的问题，本文总结了近年来石墨材料应用于钾基能源存储的研究进展，分析了插层机理并揭示了电化学性能与石墨结构，电解液和黏结剂之间的关系。最后，总结并展望了石墨材料在钾基能源存储中应用的发展方向。
- 石墨 /
- 钾离子电池 /
- 钾基双离子电池
Abstract: Potassium ion batteries (KIBs) and potassium-based dual ion batteries (KDIBs) are newly-emerging energy storage devices that have attracted considerable attention owing to the low-cost of potassium resources and their comparable performance to lithium-ion batteries (LIBs). Graphite materials, as the successful commercialized anode materials of LIBs, can also be used as anodic and cathodic host materials for the intercalation of the large potassium cations and other anions, respectively. However, there are still some challenges hindering the practical application of graphite materials in the anode for KIBs and the cathode for KDIBs. The huge volume changes after intercalation (61% for K and 130% for anions) result in graphite interlayer slipping and structural collapse, causing capacity fade and a short cycle life. Moreover, the intercalation of large K⁺ and anions have poor kinetics due to the small graphite interlayer spacing, restricting the rate capability. To solve these issues of the use of graphite materials, this review attempts to provide a better understanding of the intercalation mechanisms for K⁺ and anions, and to correlate the electrochemical performance of KIBs and KDIBs to the microstructure of graphite, and the physicochemical properties of electrolytes and binders. Finally, research prospects are provided to guide the future development of graphite materials for potassium-based energy storage.
- Graphite /
- Potassium ion battery /
- Potassium-based dual ion battery

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FIG. 667. FIG. 667.

FIG. 667..

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Figure 1. The advantages, challenges and the designing strategies of graphite for potassium storage.

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Figure 2. Charge/discharge potential profiles and corresponding XRD patterns (ex or in situ) with different graphite electrodes. (a-b) Commercial graphite at C/10 (1 C=279 mAh g⁻¹) (Copyright 2015, American Chemical Society^[36]), (c) graphite at C/14 (1st and 2nd cycle) ( Reproduced with permission, Copyright 2019, Willey^[37), (d) graphite foam at C/20 (1st cycle) and (e) the discharging curve and corresponding intercalation compounds at each stage (Reproduced with permission, Copyright 2019, Willey^[38]).

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Figure 3. (a) The ex-situ XRD patterns of an expanded graphite cathode with the different intercalation/de intercalation stages (Reproduced with permission, Copyright 2017, Willey^[42]), (b) the in-plane structure of C₂₄PF₆(Reproduced with permission, Copyright 2014, Willey^[43]) and (c-d) schematics of the staging mechanism of intercalation of FSI^- anion into the graphite and the in-situ XRD of the graphite electrode during the first two cycles^[44].

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Figure 4. Schematic diagram of various structured graphite electrodes that have been reported for the potassium-based energy storage.

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Figure 5. (a) The rate retentions and capacities of the CNC anode at different current densities, (b) schematic illustration of structural variations of CNC and MG electrodes during potassium storage (Reproduced with permission, Copyright 2019, Willey^[48]).

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Table 1. The overview of three ions (cation and anion) for potassium-based energy storage.

Cation/ anion	Ion radius/ dimensions (Å)	GIC stoichiometry	Volume change	Specific capacity/ mAh g⁻¹
K⁺	1.38	KC₈	61%	279
PF₆^-	3.5×3.5	C₂₄PF₆	136%	93
FSI^-	5.4×2.6	C₆[FSI]_0.5	134%	186
Note: Å- 0.1 nm

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Table 2. Electrochemical performance of different graphite anodes in KIBs (1 C=279 mAh g⁻¹).

Materials	Electrolyte	Binder	Initial coulombic efficiency	Initial charge capacity (mAh g⁻¹)	Cyclability	Rate performance (mAh g⁻¹)	Refs.
Graphite	0.5 M KPF₆ in EC/DEC=1∶1	PVDF	74.3%	208 at 5 mA g⁻¹		141 at 200 mA g⁻¹	[23]
Natural graphite powder (particle size 3 μm)	1 M KFSI in EC:DEC = 1∶1	PANa	79%	~240 at C/10	~250 at C/10 after 50 cycles		[31]
		CMCNa	89%	~230 at C/10	~240 at C/10 after 8 cycles
		PVDF	59%	~225 at C/10	~230 at C/10 after 20 cycles
Commercially available synthetic graphite	0.8 M KPF₆ in EC:DEC = 1∶1	PVDF	57.4%	273 at C/40	100 at C/2 after 50 cycles	80 at 1 C	[36]
KS4 graphite	1 M KPF₆ in EC:PC = 1∶1	Na-alginate	66.5%	246 at 20 mA g⁻¹	220 at 20 mA g⁻¹ after 200 cycles	~0 at 500 mA g⁻¹	[45]
	1 M KPF₆ in EC:PC = 1∶1	PVDF	44.5%	~240 at 20 mA g⁻¹	200 at 20 mA g⁻¹ after 15 cycles
	1 M KPF₆ in EC:DEC = 1∶1	Na-alginate	47.0%	~240 at 20 mA g⁻¹	200 at 20 mA g⁻¹ after 100 cycles
	1 M KPF₆ in EC:DMC = 1∶1		42.7%	~240 at 20 mA g⁻¹	~0 at 20 mA g⁻¹ after 140 cycles
Activated carbon from the graphite	0.8 M KPF₆ in EC:DEC = 1∶1	PVDF		260 at 50 mA g⁻¹	100.3 at 200 mA g⁻¹ after 100 cycles	30 at 1000 mA g⁻¹	[46]
Commercial graphite	1 M KFSI in EC:DEC = 1∶1	CMC	80.83%	163 at 50 mA g⁻¹	61 at 50 mA g⁻¹ after 200 cycles	44 at 200 mA g⁻¹	[47]
Commercial expanded graphite	1 M KFSI in EC:DEC = 1∶1	CMC	81.56%	218 at 50 mA g⁻¹	228 at 50 mA g⁻¹ after 100 cycles	175 at 200 mA g⁻¹	[47]
Mesophase graphite	1 M KFSI in EC:PC = 1∶1	3 wt.% CMC and 6 wt.% PAA		248 at 0.2 C	154 at 0.2 C after 50 cycles	30 at 1 C	[48]
Graphitic Carbon Nanocage	1 M KFSI in EC:PC = 1∶1	3 wt.% CMC and 6 wt.% PAA	40%	212 at 0.2 C	195 at 0.2 C after 100 cycles	99 at 1 C 56 at 3 C	[48]
Ball-milled graphite	0.8 M KPF₆ in EC:DEC = 1∶1	PVDF	61%	211 at 25 mA g⁻¹	100 at 25 mA g⁻¹ after 200 cycles		[49]
Graphite	0.8 M KPF₆ in EC:EMC, 1∶1	CMC			20 at C/3 after 300 cycles		[37]
Graphite	KFSI:EMC, 1:2.5, molar ratio			~170 at C/3	255 at C/3 after 2000 cycles		[37]
Carbon nanotubes-interweaved layer on graphite flakes	0.8 M KPF₆ in EC:PC, 1∶1	CMC-Na	40.7%	293.8 at 200 mA g⁻¹	245 at 200 mA g⁻¹ after 600 cycles	222.3 at 4000 mA g⁻¹	[50]
Graphite	1 M KPF₆ in DME	CMC	87.4%	~95 at 1 C	80 at 1 C after 700 cycles	90 at 0.5 C 82 at 10 C	[51]
Graphite	1 M KPF₆ in EC/DMC = 1∶1	CMC	69.6%	~95 at 1 C	17 at 1 C after 700 cycles	220 at 0.5 C 8 at 10 C	[51]
Polynanocrystalline Graphite	0.8 M KPF₆ in EC:DEC = 1∶1	CMC	54.1%	224 at 20 mA g⁻¹	~70 at 100 mA after 300 cycles	99 at 200 mA g⁻¹ 13.6 at 1000 mA g⁻¹	[52]
Graphitic Nanocarbon	0.8 M KPF₆ in EC:DEC = 1∶1	CMC-Na		369 at 50 mA g⁻¹	189 at 200 mA g⁻¹ after 200 cycles	152 at 1000 mA g⁻¹	[53]
Note: M- mol L⁻¹

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Table 3. Electrochemical performance of KDIBs.

Cathode	Anode	Electrolyte	Voltage window (V)	Energy density (Wh kg⁻¹)	Cyclability (mAh g⁻¹)	Rate performance (mAh g⁻¹)	Refs.
Available synthetic flake-type graphite	Available synthetic flake-type graphite	ionic liquid (Pyr14TFSI + 0.3 M KTFSI + 2 wt% ES)	3.4–5.0		47 at 50 mA g⁻¹ after 100 cycles	42 at 250 mA g⁻¹	[32]
Nanographite	Nanographite	0.8 M KPF₆ in EC:DMC =1∶1	3.0–5.0		62 at 100 mA g⁻¹ after 60 cycles	45 at 250 mA g⁻¹	[64]
Expanded graphite	Metal foil	1 M KPF₆ in EC+DMC+ EMC = 4∶3∶2	3.0–5.0	116	66 at 50 mA g⁻¹ after 300 cycles	52 at 300 mA g⁻¹g	[65]
Expanded graphite	Mesocarbon microbead	1 M KPF₆ in EC+DMC+ EMC = 4∶3∶2	3.0–5.2		61 at 100 mA g⁻¹ after 100 cycles	52 at 300 mA g⁻¹	[42]
Expanded graphite	Porous carbon	1 M KPF₆ in EC+DMC+ EMC = 4∶3∶2	1.0–3.8	117	63 at 1000 mA g⁻¹ after 2000 cycles	82 at 3000 mA g⁻¹	[69]
KS6 graphite	Natural graphite	0.8 M KPF₆ in EC:DEC =1∶1	2.4–5.4	158.3	50.5 at 100 mA g⁻¹ after 400 cycles	16.3 at 300 mA g⁻¹	[66]
Note: M- mol L⁻¹

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