This article is part of the series IFFM&AFM2011 .

Open Access Nano Express

LiNi0.4Co0.3Mn0.3O2 thin film electrode by aerosol deposition

Icpyo Kim1, Tae-Hyun Nam1, Ki-Won Kim1, Jou-Hyeon Ahn2, Dong-Soo Park3, Cheolwoo Ahn3, Byong Sun Chun5, Guoxiu Wang14 and Hyo-Jun Ahn1*

Author Affiliations

1 School of Materials Science and Engineering, ERI, Gyeongsang National University, Jinju, 660-701, South Korea

2 Department of Chemical and Biological Engineering, Gyeongsang National University, Jinju, 660-701, South Korea

3 Functional Materials Division, Korea Institute of Materials Science, Changwon, 641-831, South Korea

4 Centre for Clean Energy Technology, Department of Chemistry and Forensic Science, University of Technology Sydney, Broadway, Sydney, NSW 2007, Australia

5 ReSEAT Program, KISTI, Daejeon, 305-806, South Korea

For all author emails, please log on.

Nanoscale Research Letters 2012, 7:64  doi:10.1186/1556-276X-7-64


The electronic version of this article is the complete one and can be found online at: http://www.nanoscalereslett.com/content/7/1/64


Received:19 September 2011
Accepted:5 January 2012
Published:5 January 2012

© 2012 Kim et al; licensee Springer.

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

LiNi0.4Co0.3Mn0.3O2 thin film electrodes are fabricated from LiNi0.4Co0.3Mn0.3O2 raw powder at room temperature without pretreatments using aerosol deposition that is much faster and easier than conventional methods such as vaporization, pulsed laser deposition, and sputtering. The LiNi0.4Co0.3Mn0.3O2 thin film is composed of fine grains maintaining the crystal structure of the LiNi0.4Co0.3Mn0.3O2 raw powder. In the cyclic voltammogram, the LiNi0.4Co0.3Mn0.3O2 thin film electrode shows a 3.9-V anodic peak and a 3.6-V cathodic peak. The initial discharge capacity is 44.6 μAh/cm2, and reversible behavior is observed in charge-discharge profiles. Based on the results, the aerosol deposition method is believed to be a potential candidate for the fabrication of thin film electrodes.

Keywords:
thin film; aerosol deposition; battery

Introduction

Batteries can be applied to microelectronic and portable devices as power sources [1-3]. Also, many endeavors have been made to develop batteries for high power and energy for electric vehicles [4,5]. Although lithium-ion batteries, among all other batteries, are the most promising type owing to their large energy storage density, commercial lithium-ion batteries contain a flammable liquid electrolyte, which has induced safety concerns. In order to mitigate the safety issue, an all-solid-state battery is a viable candidate as it is composed of thin film electrodes and a solid electrolyte. Moreover, the thin film electrode usually is composed of an active material without a binder. Owing to these advantages, many studies have been conducted to fabricate all-solid-state batteries through various methods, such as pulsed laser deposition [6-13], electrostatic spray deposition [14-16], and sputtering deposition [17-26]. Although these methods are very efficient for the preparation of thin film electrodes, they have several disadvantages, such as their complex fabrication processes, difficulty in controlling the composition of the thin film, and their low deposition rate.

Aerosol deposition method was recently developed that differs from aerosol flame deposition in which the materials are prepared through a hydrolysis reaction of aerosol precursor solutions by flame [27]. The aerosol deposition method can be used for various applications, such as biomaterial and ceramic sensors [28-30]. In the aerosol deposition method, powder is mixed with gas to make an aerosol, and this aerosol is ejected onto the substrate to form a thin film. In other words, the aerosol deposition is a room-temperature impact-consolidation method. Thus, the aerosol deposition method has excellent advantages. These include its room temperature process, high deposition rate, high adhesion strength, easy control of the composition of the thin film, and its simple process. Furthermore, the aerosol deposition method does not require high vacuum devices, and the bare powder can be used directly without a pretreatment.

LiNi0.4Co0.3Mn0.3O2 in the LiNixCoyMnzO2 system was chosen as an active material on the account of its low cost, low toxicity, thermal stability, high capacity, and good cycle life [31,32]. Xie et al. [25] recently reported a LiNi0.33Mn0.33Co0.33O2 thin film electrode prepared via a sputtering method. The LiNi0.33Mn0.33Co0.33O2 thin film electrode presented excellent results such as a high discharge capacity of more than 120 mAh/g. However, there was no report on the LiNi0.4Co0.3Mn0.3O2 thin film electrode. A complex conventional procedure was undertaken to deposit this thin film in their study. The aerosol deposition method was believed to have the ability to simplify this complex procedure, and no report has been made on using this method for the preparation of the thin film electrode.

In this study, a LiNi0.4Co0.3Mn0.3O2 thin film was prepared by aerosol deposition, and its electrochemical property was characterized. From these results, the feasibility of aerosol deposition as a new preparation method for thin film electrodes was discussed.

Experimental details

We prepared LiNi0.4Co0.3Mn0.3O2 thin film electrodes from the LiNi0.4Co0.3Mn0.3O2 raw powder, which was purchased from DAEJUNG EM in Buchun-City, Korea and was used without any special pretreatment using the aerosol deposition apparatus (built in-house) as shown in Figure 1. Stainless steel (SUS304) was used as a substrate. The detailed AD procedure was described in our previous report [33].

thumbnailFigure 1. Schematic diagram of aerosol deposition.

To investigate the crystal structures, the LiNi0.4Co0.3Mn0.3O2 powder and thin film electrodes were analyzed by an X-ray diffractometer (D8 Bruker; Karlsruhe, Germany) employing Cu Kα radiation. A field emission scanning electron microscope [FESEM] (Philips XL30S FEG; Philips, Amsterdam, Netherlands) was used for clarifying the surface morphologies. For the measurement of electrochemical properties, a Swagelok-type cell was employed. The thin film electrodes were used as working electrodes, and a lithium metallic foil was designated as counter electrode. The electrolyte solution was 1 mol LiPF6 in EC + DEC (1:1 (v/v)). The assemblies of the cells were conducted in an Ar-filled glove box. Potentiostatic tests were carried out at a sweep rate of 0.1 mV/s between 2.5 and 4.2 V for the thin film electrode, and galvanostatic tests were performed at a constant current density of 1 μA/cm2 in the same voltage range.

Results and discussions

In the aerosol deposition method, particle size of the starting powder was an important experimental factor, which was measured by WINDOX 5 (HELOS Particle Size Analysis; Sympatec Inc., Lawrenceville, NJ, USA). Figure 2 presents the cumulative distribution of the particle size of LiNi0.4Co0.3Mn0.3O2 raw powder, which ranged from the submicron to 11 μm. The average particle size was 1.9 μm. Figure 3 shows FESEM images of the LiNi0.4Co0.3Mn0.3O2 raw powder and thin film electrode. The LiNi0.4Co0.3Mn0.3O2 powder presented an agglomeration of small particles. This LiNi0.4Co0.3Mn0.3O2 powder was deposited uniformly, and the thin film had a rough and flat surface in low magnification. In high magnification, the thin film electrode consisted of fine particles of less than several hundred nanometers. During the aerosol deposition process, the original particles could be crushed into fine particles upon the moment of impact on the substrate. These fractured fine particles strongly attached to the substrate, as explained in a previous report [34]. Thus, based on the particle size analysis result, the original particles that were considered became small by more than half of the original size. The thickness of the thin film was about 2.6 μm as measured by α-step measurements, and 1 min was consumed for the deposition. Thus, the deposition rate of the thin film could be about 2.6 μm/min, which was much faster than that of conventional deposition methods.

thumbnailFigure 2. The cumulative distribution of particle size of LiNi0.4Co0.3Mn0.3O2 raw powder.

thumbnailFigure 3. SEM micrographs. LiNi0.4Co0.3Mn0.3O2 (a) raw powder and thin film electrode at a magnification of (b) ×1,000 and (c) ×40,000.

Because aerosol deposition is a shock-loading deposition method, it can induce severe strain or a change in the crystal structure of the thin film. In particular, it is well known that a LiNi0.33Co0.33Mn0.33O2-based material has a layered structure of α-NaFeO2 (R-3m) and that lithium ions lithiate/delithiate between these layers [32]. Thus, the crystal structure of the thin film can strongly affect its electrochemical properties. To investigate changes in the crystal structure of the LiNi0.4Co0.3Mn0.3O2 thin film, X-ray diffraction [XRD] measurements were conducted. Figure 4 shows the XRD patterns of the LiNi0.4Co0.3Mn0.3O2 raw powder and thin film electrode. The XRD patterns of the LiNi0.4Co0.3Mn0.3O2 raw powder confirmed the α-NaFeO2 (R-3m) structure, replicating the findings of a previous report [32,35]. However the XRD patterns of the thin film showed only one visible peak for LiNi0.4Co0.3Mn0.3O2 at 18° with three other peaks corresponding to the stainless steel substrate. This phenomenon has been reported for various thin films, and the preferred orientation of the thin film was suggested as an origin [9,25,36]. The same reason might be applied to our X-ray diffraction result. Moreover, the peak of the thin film was slightly broader than that of the raw powder, which may originate from the strain of the crystal structure or the small particle size as shown in Figure 3c.

thumbnailFigure 4. XRD patterns of the (a) LiNi0.4Co0.3Mn0.3O2 raw powder and (b) thin film electrode.

Figure 5 introduces the cyclic voltammogram [CV] of the thin film electrode. The LiNi0.4Co0.3Mn0.3O2 thin film electrode showed a 3.88-V oxidation peak and a 3.6-V reduction peak in the first cycle. Since there has been no previous study on CV of the LiNi0.4Co0.3Mn0.3O2 thin film, previous results on LiNi1/3Co1/3Mn1/3O2 bulk electrodes by Shinova et al. and He et al. [37,38] were taken into account, and from comparison, a similarity of redox peak voltages was observed. The thin film electrode is believed to have electrochemical properties corresponding to those of the LiNi0.4Co0.3Mn0.3O2 bulk electrode, coinciding with the XRD result in Figure 4. In the second cycle, the reduction peak shifted slightly, but the oxidation peak appeared at 3.80 V and moved to a high voltage in the third cycle. This demonstrates that the rechargeable LiNi0.4Co0.3Mn0.3O2 thin film electrode can be fabricated for rechargeable all-solid-state batteries by aerosol deposition method. However, the redox peaks were broad, and the peak voltages shifted. The aerosol deposition method is based on the impact adhesion of particles, which means that the particles yield a large strain in itself from the impact. Thus, the broadness and the voltage shifts of redox peaks are believed to be attributed to the severe strain of particles.

thumbnailFigure 5. Cyclic voltammogram of the LiNi0.4Co0.3Mn0.3O2 thin film electrode at a scan rate of 0.1 mV/s.

The charge-discharge curves of the LiNi0.4Co0.3Mn0.3O2 thin film electrode are presented in Figure 6. The thin film electrode yielded the first charge and discharge capacities, 42.8 and 44.7 μAh/cm2, respectively. In the second cycle, the charge capacity increased to 45.4 μAh/cm2, and the discharge capacity decreased to 43.5 μAh/cm2. Rechargeability of the thin film electrode was introduced in accordance with the CV result. In the previous report on amorphous Li[Ni1/3Co1/3Mn1/3]O2 positive electrode by Xie et al. [25], an irreversible capacity was presented at the first cycle, but the LiNi0.4Co0.3Mn0.3O2 thin film electrode exhibited this at the second cycle. The plateau voltages of the charge and discharge curves decreased in the second cycle. As described above, aerosol deposition is based on shock-loading solidification. Therefore, a large strain can be introduced into the thin film, which is released during initial cycles and induces the partial collapse or change of the crystal structure of the thin film; thus, the capacity and potential can be affected. The sloped flat region of the discharge curves could be attributed to several factors such as current density and crystal structure of the active material, but the current density of 1 μA/cm2 was quite low compared to the capacity of 44.7 μAh/cm2. Thus, we believe that the damaged crystal structure also contributed the discharge behavior of the thin film electrode.

thumbnailFigure 6. The charge and discharge curves of the LiNi0.4Co0.3Mn0.3O2 thin film electrode.

Conclusions

The feasibility of the aerosol deposition method for the fabrication of thin film electrodes was investigated. LiNi0.4Co0.3Mn0.3O2 thin film electrode was prepared within 10 min and had a flat surface composed of fine particle with the α-NaFeO2 crystal structure. According to cyclic voltammogram measurement, the thin film electrode showed a 3.9-V anodic peak and a 3.6-V cathodic peak. The discharge capacity was 44.7 μAh/cm2 with a 3.6-V plateau region. Based on these results, the aerosol deposition method is a good candidate for the fabrication of thin film electrodes, which can be used in all-solid-state rechargeable batteries.

Competing interests

The authors declare that they have no competing interests.

Authors' contributions

IK carried out the electrochemical experiments and drafted the manuscript. THN participated in the crystallographic studies, and KWK and JHA did the electrochemical studies. DSP and CA carried out the deposition of the thin film. BSC participated by proofreading the manuscript. GW participated in the analysis of the materials. HJA conceived the study and participated in its design and coordination. All authors read and approved the final manuscript.

Acknowledgements

We gratefully acknowledge the financial supports from the KIMS Internal Program 'Development of Advanced Powder Materials Technology for New Growth Engine and Its Transfer to Industry' and the World Class University (WCU) program through the National Research Foundation of Korea (grant number; R32-2008-000-20093-0).

References

  1. Ohtsuka H, Sakurai Y: Characteristics of Li/MoO3-x thin film batteries.

    Solid State Ionics 2001, 144:59-64. Publisher Full Text OpenURL

  2. Souquet JL, Duclot M: Thin film lithium batteries.

    Solid State Ionics 2002, 148:375-379. Publisher Full Text OpenURL

  3. Yamamoto K, Iriyama Y, Asaka T, Hirayama T, Fujita H, Fisher CAJ, Nonaka K, Sugita Y, Ogumi Z: Dynamic visualization of the electric potential in an all-solid-state rechargeable lithium battery.

    Angew Chem Int Ed 2010, 49:4414-4417. Publisher Full Text OpenURL

  4. Liu J, Xue D: Hollow nanostructured anode materials for Li-Ion batteries.

    Nanoscale Res Lett 2010, 5:1525-1534. PubMed Abstract | Publisher Full Text | PubMed Central Full Text OpenURL

  5. Nam SH, Kim YS, Shim H-S, Kim JG, Kim WB: Copper nanofiber-networked cobalt oxide composites for high performance Li-ion batteries.

    Nanoscale Res Lett 2011, 6:292. PubMed Abstract | BioMed Central Full Text | PubMed Central Full Text OpenURL

  6. Iriyama Y, Inaba M, Abe T, Ogumi Z: Preparation of c-axis oriented thin films of LiCoO2 by pulsed laser deposition and their electrochemical properties.

    J Power Sources 2001, 94:175-182. Publisher Full Text OpenURL

  7. Iriyama Y, Kurita H, Yamada I, Abe T, Ogumi Z: Effects of surface modification by MgO on interfacial reactions of lithium cobalt oxide thin film electrode.

    J Power Sources 2004, 137:111-116. Publisher Full Text OpenURL

  8. Kuwata N, Kawamura J, Toribami K, Hattori T, Sata N: Thin-film lithium-ion battery with amorphous solid electrolyte fabricated by pulsed laser deposition.

    Electrochem Commun 2004, 6:417-421. Publisher Full Text OpenURL

  9. Sauvage F, Baudrin E, Gengembre L, Tarascon J-M: Effect of texture on the electrochemical properties of LiFePO4 thin films.

    Solid State Ionics 2005, 176:1869-1876. Publisher Full Text OpenURL

  10. Yada C, Iriyama Y, Jeong SK, Abe T, Inaba M, Ogumi Z: Electrochemical properties of LiFePO4 thin films prepared by pulsed laser deposition.

    J Power Sources 2005, 146:559-564. Publisher Full Text OpenURL

  11. Xia H, Lu L, Ceder G: Li diffusion in LiCoO2 thin films prepared by pulsed laser deposition.

    J Power Sources 2006, 159:1422-1427. Publisher Full Text OpenURL

  12. Baskaran R, Kuwata N, Kamishima O, Kawamura J, Selvasekarapandian S: Structural and electrochemical studies on thin film LiNi0.8Co0.2O2 by PLD for micro battery.

    Solid State Ionics 2009, 180:636-643. Publisher Full Text OpenURL

  13. Chen CH, Kelder EM, Jak MJG, Schoonman J: Electrostatic spray deposition of thin layers of cathode materials for lithium battery.

    Solid State Ionics 1996, 86-88:1301-1306. OpenURL

  14. Yu Y, Shui JL, Jin Y, Chen CH: Electrochemical performance of nano-SiO2 modified LiCoO2 thin films fabricated by electrostatic spray deposition (ESD).

    Electrochim Acta 2006, 51:3292-3296. Publisher Full Text OpenURL

  15. Shui JL, Jiang GS, Xie S, Chen CH: Thin films of lithium manganese oxide spinel as cathode materials for secondary lithium batteries.

    Electrochim Acta 2004, 49:2209-2213. Publisher Full Text OpenURL

  16. Liao C-L, Fung K-Z: Lithium cobalt oxide cathode film prepared by rf sputtering.

    J Power Sources 2004, 128:263-269. Publisher Full Text OpenURL

  17. Yamaki J, Ohtsuka H, Shodai T: Rechargeable lithium thin film cells with inorganic electrolytes.

    Solid State Ionics 1996, 86-88:1279-1284. OpenURL

  18. Bates JB, Dudney NJ, Neudecker BJ, Hart FX, Jun HP, Hackney SA: Preferred orientation of polycrystalline LiCoO2 films.

    J Electrochem Soc 2000, 147:59-70. Publisher Full Text OpenURL

  19. Bates JB, Dudney NJ, Neudecker B, Ueda A, Evans CD: Thin-film lithium and lithium-ion batteries.

    Solid State Ionics 2000, 135:33-45. Publisher Full Text OpenURL

  20. Whitacre JF, West WC, Brandon E, Ratnakumar BV: Crystallographically oriented thin-film nanocrystalline cathode layers prepared without exceeding 300°C.

    J Electrochem Soc 2001, 148:A1078-A1084. Publisher Full Text OpenURL

  21. Park HY, Lee SR, Lee YJ, Cho BW, Cho WI: Bias sputtering and characterization of LiCoO2 thin film cathodes for thin film microbattery.

    Mater Chem Phys 2005, 93:70-78. Publisher Full Text OpenURL

  22. Schwenzel J, Thangadurai V, Weppner W: Developments of high-voltage all-solid-state thin-film lithium ion batteries.

    J Power Sources 2006, 154:232-238. Publisher Full Text OpenURL

  23. Hayashi M, Takahashi M, Sakurai Y: Preparation of positive LiCoO2 films by electron cyclotron resonance (ECR) plasma sputtering method and its application to all-solid-state thin-film lithium batteries.

    J Power Sources 2007, 174:990-995. Publisher Full Text OpenURL

  24. Xie J, Imanishi N, Matsumura T, Hirano A, Takeda Y, Yamamoto O: Orientation dependence of Li-ion diffusion kinetics in LiCoO2 thin films prepared by RF magnetron sputtering.

    Solid State Ionics 2008, 179:362-370. Publisher Full Text OpenURL

  25. Xie J, Imanishi N, Zhang T, Hirano A, Takeda Y, Yamamoto O: An amorphous LiCo1/3Mn1/3Ni1/3O2 thin film deposited on NASICON-type electrolyte for all-solid-state Li-ion batteries.

    J Power Sources 2010, 195:5780-5783. Publisher Full Text OpenURL

  26. Cho GB, Song MG, Bae SH, Kim JK, Choi YJ, Ahn HJ, Ahn JH, Cho KK, Kim KW: Surface-modified Si thin film electrode for Li ion batteries (LiFePO4/Si) by cluster-structured Ni under layer.

    J Power Sources 2009, 189:738. Publisher Full Text OpenURL

  27. Cho KH, Oh JW, Lee TW, Shin DW: Effect of P2O5 in Li2O-P2O5-B2O3 electrolyte fabricated by aerosol flame deposition.

    J Power Sources 2008, 183:431-435. Publisher Full Text OpenURL

  28. Hahn BD, Lee JM, Park DS, Choi JJ, Ryu JH, Yoon WH, Lee BK, Shin DS, Kim HE: Aerosol deposition of silicon-substituted hydroxyapatite coatings for biomedical applications.

    Thin Solid Films 2010, 518:2194-2199. Publisher Full Text OpenURL

  29. Ryu JH, Hahn BD, Choi JJ, Yoon WH, Lee BK, Choi JH, Park DS: Porous photocatalytic TiO2 thin films by aerosol deposition.

    J Am Ceram Soc 2010, 93:55-58. Publisher Full Text OpenURL

  30. Ryu JH, Choi JJ, Hahn BD, Yoon WH, Lee BK, Choi JH, Park DS: Pb(Zr, Ti)O3-Pb(Mn1/3Nb2/3)O3 piezoelectric thick films by aerosol deposition.

    Mater Sci Eng B 2010, 170:67-70. Publisher Full Text OpenURL

  31. Kang SH, Abraham DP, Yoon WS, Nam KW, Yang XQ: First-cycle irreversibility of layered Li-Ni-Co-Mn oxide cathode in Li-ion batteries.

    Electrochim Acta 2008, 54:684-689. Publisher Full Text OpenURL

  32. Lee K-S, Myung S-T, Amine K, Yashiro H, Sun Y-K: Structural and electrochemical properties of layered Li[Ni1-2xCoxMnx]O2 (x = 0.1-0.3) positive electrode materials for Li-Ion batteries.

    J Electrochem Soc 2007, 154:A971-A977. Publisher Full Text OpenURL

  33. Ryu J, Choi JJ, Hahn BD, Park DS, Yoon WH: Ferroelectric and piezoelectric properties of 0.948(K0.5Na0.5)NbO3-0.052LiSbO3 lead-free piezoelectric thick film by aerosol deposition.

    Appl Phys Lett 2008, 92:012905. Publisher Full Text OpenURL

  34. Akedo J: Room temperature impact consolidation (RTIC) of fine ceramic powder by aerosol deposition method and applications to microdevices.

    J Thermal Spray Technol 2008, 17:181-198. Publisher Full Text OpenURL

  35. Sun YK, Kim DH, Yoon CS, Myung ST, Prakash J, Amine K: A novel cathode material with a concentration-gradient for high-energy and safe lithium-ion batteries.

    Adv Funct Mater 2010, 20:485-491. Publisher Full Text OpenURL

  36. Matsumura T, Imanishi N, Hirano A, Sonoyama N, Takeda Y: Electrochemical performances for preferred oriented PLD thin-film electrodes of LiNi0.8Co0.2O2, LiFePO4 and LiMn2O4.

    Solid State Ionics 2008, 179:2011-2015. Publisher Full Text OpenURL

  37. He YS, Pei L, Liao XZ, Ma ZF: Synthesis of LiNi1/3Co1/3Mn1/3O2-zFz cathode material from oxalate precursors for lithium ion battery.

    J Fluorine Chem 2007, 128:139-143. Publisher Full Text OpenURL

  38. Shinova E, Stoyanova R, Zhecheva E, Ortiz GF, Lavela P, Tirado JL: Cationic distribution and electrochemical performance of LiCo1/3Ni1/3Mn1/3O2 electrodes for lithium-ion batteries.

    Solid State Ionics 2008, 179:2198-2208. Publisher Full Text OpenURL