Lithium Nickel Oxide Research Articles

Achieving high performance and stable inverted planar perovskite solar cells using lithium and cobalt co-doped nickel oxide as hole transport layers

Herein, we demonstrate that lithium and cobalt co-doped NiOx hole transport layers can greatly enhance the device performance of inverted planar heterojunction perovskite solar cells.

Lithium and Silver Co-Doped Nickel Oxide Hole-Transporting Layer Boosting the Efficiency and Stability of Inverted Planar Perovskite Solar Cells.

In this work, a lithium and silver co-doping strategy has been successfully implied to prepare NiO x films for high performance inverted planar perovskite solar cells (PSCs). Compared to the pristine and single-doped NiO x, the Li and Ag co-doping approach exhibits the synergistic effect and can endow NiO x films with higher electrical conductivity, higher hole mobility and better interface energy band alignment with perovskite active layers. Moreover, the perovskite film with enhanced crystallinity can be obtained induced by the Li,Ag:NiO x film. The PSC with Li,Ag:NiO x HTL shows a high power conversion efficiency (PCE) up to 19.24% and less hysteresis effect, which outperforms the devices with the pristine NiO x or single-doped NiO x HTLs. Meanwhile, the Li,Ag:NiO x device can retain 95% of its initial PCE after storage at the relative humidity of 30 ± 2% in 30 days without encapsulation. Our work demonstrates that lithium and silver co-doping is a promising route for realizing efficient p-type NiO x HTL, which provides a simple way to boost the efficient and stable of inverted planar PSCs.

Coupled LiPF6 Decomposition and Carbonate Dehydrogenation Enhanced by Highly Covalent Metal Oxides in High-Energy Li-Ion Batteries

The (electro)chemical reactions between positive electrodes and electrolytes are not well understood. We examined the oxidation of a LiPF6-based electrolyte with ethylene carbonate (EC) with layered lithium nickel, manganese, and cobalt oxides (NMC). Density functional theory calculations showed that the driving force for EC dehydrogenation on oxides, yielding surface protic species, increased with greater Ni content in NMC. Ex situ infrared and Raman spectroscopy revealed experimental evidence for EC dehydrogenation on charged NMC surfaces. Protic species on charged NMC surfaces from EC dehydrogenation could further react with LiPF6 to generate less-coordinated F species such as PF3O-like and lithium nickel oxyfluoride species on charged NMC particles and HF and PF2O2– in the electrolyte. Larger degree of salt decomposition was coupled with increasing EC dehydrogenation on charged NMC with increasing Ni or lithium deintercalation. An oxide-mediated chemical oxidation of electrolytes was proposed, providi...

Unexpectedly high energy density of a Li-Ion battery by oxygen redox in LiNiO2 cathode: First-principles study

Conventionally neglected mechanism of reversible redox reactions by oxygen ions in lithium-nickel oxide materials (LNO; Li2xNi2-2xO2, 0 < x < 1) is proposed as a primary cause of unexpectedly high energy density of Li-ion battery. Using first-principles density functional theory calculations, cluster expansion theory, and Monte Carlo simulations, we unveil the underlying mechanism that is ascribed to the phase transition between layered and rocksalt structures initiated by cation disordering of Li and Ni at certain Li composition. At x = 0.5, the oxygen ions are put under specific chemical bondings of straight-linear type LiOLi configuration. They enable an active oxygen redox reaction involving peroxo (O22−) and superoxo (O2−) ions, shown to dramatically increase the energy density of the LNO cathode. Using Monte Carlo simulations, we identify the proportional information to find the LiOLi configurations around the synthetic temperature of LNO materials. Our results indicate that the cation-disorder is a driving force for the oxygen redox via formation of the specific bondings. On the basis of our study, it is expected to provide useful guidelines for the design of Li-ion batteries with high energy densities beyond conventional ones.

Matthey advances new battery material

Johnson Matthey will build a 1,000-metric-ton-per-year facility at its site in Clitheroe, England, to produce sample quantities of its enhanced lithium nickel oxide (eLNO) electric-vehicle battery ...

Studies on the local structures for the trigonal Ni3+ centers in cathode materials LiAly Co1-y O2 (y=0, 0.1, 0.5, and 0.8).

The local angular distortions Δθ are theoretically studied for the various Ni3+ centers in LiAly Co1-y O2 at different Al concentrations (y=0, 0.1, 0.5, and 0.8) based on the perturbation calculations of electron paramagnetic resonance g factors for a trigonally distorted octahedral 3d7 cluster with low spin (S=1/2). Due to the Jahn-Teller effect, the [NiO6 ]9- clusters are found to experience the local angular distortions (Δθ≈5°-9°) along the C3 axis. The variation trend of Δθ with y is in accordance with that of anisotropy (Δg=g|| -g⊥ ). As the substitutions can weaken bond strengths between transition metal and oxygen and the structural stability plays an important role in cathode performances, detailed investigations on the structural properties of the cathode materials LiAly Co1-y O2 can be practically helpful to understand the performances of these materials. The oxy-redox properties of LiAly Co1-y O2 systems are comprehensible in the framework of Ni3+ /Ni4+ couples, and the trigonally compressed octahedral [NiO6 ]9- clusters are applicable to the clarification of the electrochemical properties of lithium nickel oxide batteries. It appears that LiAl0.8 Co0.2 O2 with the largest Al concentration may correspond to the smallest distortion among the mixing systems.

Electrochemical Water Splitting by Pseudo‐spinel, Disordered and Layered Lithium Nickel Oxides: Correlation between Structural Motifs and Catalytic Properties

AbstractIn this work, three different structures of lithium nickel oxide (LNO) synthesized by simple methods as inexpensive and efficient electrocatalyst for OER were presented. The catalytic activities of LNO catalysts for OER were pseudo‐spinel (PS‐LiNiO2) &gt; disordered (DO‐LiNiO2) &gt; layered (L‐LiNiO2) lithium nickel oxide. Particularly, PS‐LiNiO2 demonstrated much lower tafel slope of 62 mV dec−1 with the highest durability whereas the layered LNO catalysts exhibited the higher tafel slope of 88 mV dec −1, respectively. To elucidate the origin of high activities of LNO catalysts, three structures of LNO were studied by EXAFS measurements and DFT theoretical calculation. Compared to L‐LiNiO2, PS‐LiNiO2, including Ni4O4 cubane structural motifs, exhibited higher valent states and lower Ni d‐band center to drive the catalytic reaction. Thus, our results demonstrated that the activities of LNO can be optimized by controlling the value states, chemical and local electronic structure of Ni via novel design approaches.

The Coupling between Mechanics and Intercalation Chemistry in Layered Battery Materials

In addition to a change in lattice parameters, many materials also experience complex structural transformations upon intercalation. For example, many layered lithium and sodium oxides transform between the O3/O1/P3 stacking sequences, and Ni and Mn oxides often undergo transformations associated with collective Jahn-Teller distortions. Many questions remain about how these structural transformations affect battery performance, and in particular, how they affect cycle life limitations arising from fracture and mechanical damage. Here we present new models to capture the coupling between intercalation chemistry and mechanics arising from stacking-sequence changes and Jahn-Teller distortions. This includes first-principles simulations and mesoscale models to elucidate the thermodynamics and kinetics of stacking sequence changes, as well as analyses of how these transformations might result in irreversible changes to microstructure. Regarding the mechanics of Jahn-Teller distortions, we have developed anharmonic vibrational models to explore the transition from a collective distortion to a dynamic one in layered materials such as lithium nickel and manganese oxides (as well as their sodium analogues). Numerical simulations reveal how the interplay between the shape of the Jahn-Teller energy landscape and rigidity of the crystal impact the local structure and thermodynamic properties of the dynamically distorted phase.

Influence of Temperature on the Performance of LiNi1/3Co1/3Mn1/3O2 Prepared by High‐Temperature Ball‐Milling Method

Aiming at the preparation of high electrochemical performance LiNi1/3Co1/3Mn1/3O2 cathode material for lithium‐ion battery, LiNi1/3Co1/3Mn1/3O2 was prepared with lithium carbonate, nickel (II) oxide, cobalt (II, III) oxide, and manganese dioxide as raw materials by high‐temperature ball‐milling method. Influence of ball‐milling temperature was investigated in this work. It was shown that the fine LiNi1/3Co1/3Mn1/3O2 powder with high electrochemical performance can be produced by the high‐temperature ball‐milling process, and the optimal ball‐milling temperature obtained in the current study was 750°C. Its initial discharge capacity was 146.0 mAhg−1 at the rate of 0.1 C, and over 50 cycles its capacity retention rate was 90.2%.

First-Principles Simulation of the (Li–Ni–Vacancy)O Phase Diagram and Its Relevance for the Surface Phases in Ni-Rich Li-Ion Cathode Materials

Despite several reports on the surface phase transformations from a layered to a disordered spinel and a rock-salt structure at the surface of the Ni-rich cathodes, the precise structures and compositions of these surface phases are unknown. The phenomenon, in itself, is complex and involves the participation of several contributing factors. Of these factors, transition metal (TM) ion migration toward the interior of the particle and hence formation of TM-densified surface layers, triggered by oxygen loss, is thermodynamically probable. Here, we simulate the thermodynamic phase equilibria as a function of TM ion content in the cathode material in the context of lithium nickel oxides, using a combined approach of first-principles density functional calculations, the cluster expansion method, and grand canonical Monte Carlo simulations. We developed a unified lattice Hamiltonian that accommodates not only rock-salt like structures but also topologically different spinel-like structures. Also, our model prov...

Understanding the Degradation Mechanism of Lithium Nickel Oxide Cathodes for Li-Ion Batteries.

The phase transition, charge compensation, and local chemical environment of Ni in LiNiO2 were investigated to understand the degradation mechanism. The electrode was subjected to a variety of bulk and surface-sensitive characterization techniques under different charge-discharge cycling conditions. We observed the phase transition from the original hexagonal H1 phase to another two hexagonal phases (H2 and H3) upon Li deintercalation. Moreover, the gradual loss of H3-phase features was revealed during the repeated charges. The reduction in Ni redox activity occurred at both the charge and the discharge states, and it appeared both in the bulk and at the surface over the extended cycles. The degradation of crystal structure significantly contributes to the reduction of Ni redox activity, which in turn causes the cycling performance decay of LiNiO2.

Thermal stability of ethylene carbonate reacted with delithiated cathode materials in lithium-ion batteries

Confinement tests are implemented for measuring exothermic behaviors of eight delithiated or non-lithiated cathode materials mixed with ethylene carbonate (EC) which are commonly used in lithium-ion batteries. Eight delithiated and non-lithiated cathode materials, namely lithium cobalt oxide (LixCoO2), nickel oxide (NiO2), lithium nickel oxide (LixNiO2), lithium nickel cobalt oxide (LixNi0.8Co0.2O2), manganese oxide (Mn2O4), lithium manganese oxide (LixMn2O4), cobalt oxide (Co3O4) and iron phosphate (FePO4)are mixed with EC under a programmed rate of heating, respectively. Trajectories of temperature and pressure are measured simultaneously in the confined apparatus. Characteristics of thermal runaway such as onset temperature, maximum temperature, maximum pressure, maximum self-heat rate, etc., are assessed. The ranking of thermal stabilities of delithiated cathode and non-lithiated materials with EC is discussed and compared.

Development of Lithium-Ion Battery with New Shutdown System Using Redox-Shuttle Compound

Lithium ion batteries (LIB) have been adopted for the power supply of electric vehicles, and higher energy density and larger capacity cells are now in demand. Complying with these demands means that cells under abnormal conditions could become less safe. In particular, the amount of heat due to cathode decomposition could increase if overcharged. Therefore, technology is necessary to improve the safety in overcharging conditions. A redox-shuttle compound is known as an effective protection technology for overcharging cells. A redox-shuttle compound can be reversibly oxidized and reduced at a defined potential slightly higher than the full-charge potential of the surface of cathode active materials. The oxidized redox-shuttle molecules that diffuse through the electrolytes would be reduced to their neutral state on the surface of anode active materials. Neutral molecules would then diffuse back to the cathode and be oxidized again. This shuttle reaction can convert excess energy during overcharging into heat, thereby protecting the cells by limiting the potential of the cathode to less than or equal to the oxidation potential of the shuttle molecules. However, when the overcharge current is bigger than the maximum rate of the shuttle reaction, the redox-shuttle compound cannot fully consume the current, and cathode active materials will be damaged. We designed and studied a new shutdown system that is a combination of a redox-shuttle compound and shutdown separator. In this system, the redox-shuttle compound will protect cathode active materials from overcharging, and at the same time, the separator will shut down because of the heat generated by the redox-shuttle reaction. First of all, we studied the rate of redox reaction and the temperature of the cell heated by the reaction of the redox-shuttle compound. We selected 1,4-di-tert-butyl-2,5-dimethoxybenzene as the redox-shuttle compound. The reaction potential of this material is about 3.9 V vs. Li/Li+ (From the point of view of the principle verification, we selected the redox-shuttle compound of a lower reaction potential to reduce the extra reaction while the redox-shuttle compound was reacting). The redox-shuttle compound was dissolved up to 0.15 M with a common electrolyte, EC/DEC (3/7 by volume)/ 1.0 M LiPF6 and used as a redox-shuttle electrolyte. Graphite and a mixture of lithium manganese oxide and lithium nickel oxide were used as the anode and cathode active material, respectively. Porous polypropylene (PP) and PP/polyethylene (PE)/PP stacked film were used as the separator. The melting points of PP and PE are 160°C and 130°C, respectively. Cells that varied in capacity from 3.5 to 10 Ah were prepared by changing the number of stacked layers (the size of the electrode was fixed). Each cell was charged at the rate of 0.1 to 1 C, and the cell voltage and the temperature on the surface of the cell were measured. As a result, as the cells were charged, a plateau was observed around 3.8 V of cell voltage, and the temperature of the cells increased at the same time. These results indicate that the redox-shuttle compound consumed current and converted it into heat. The increase in temperature of the cells heated by the redox-shuttle compound had a linear relationship with the charged current value (See figure 1). From this relational expression, when the charge current is higher than 10 A, the temperature of the cell can exceed 160°C (higher than the melting point of PP and PE), and ion diffusion will be protected. These results and equation suggest that the new shutdown system is capable of keeping the high energy density cells safe. On the meeting day, we will report the details of the new shutdown system and the results of the experiment using 10-Ah class cells. In particular, we will focus on the influence of the redox-shuttle reaction rate and the properties of the electrode and separator in this system.Fig. 1 Relationship between the charging current and the highest and equilibrium temperature on the surface of the cell. Figure 1

VANADIUM BASED LITHIUM NICKEL ALUMINIUMOXIDE SYSTEM WITH GOOD PERFORMANCE IN LITHIUM-ION BATTERIES

LiNixV1-x-y AlyO2, are cathode materials for lithium ion batteries which have been synthesized via carbon combustion method. Lithium nickel oxide derivatives are considered by the battery manufacturers to be very promising for application in 4V lithium-ion batteries. The objective of this study is, to successfully synthesize a lithium nickel vanadium aluminum oxide cathode which can show intercalation and de-intercalation process during cyclic voltammetry testing and a discharge capacity of above 50mAh/g. LiNi1-x-yVxAlyO2were synthesized by the carbon combustion method using acetylene carbon black as a binder. X-Ray Diffraction (XRD) reveals extra peaks related to Vanadium metal when it is added into LiNiAlO2. The intensity peak of the spectrum increased when the V content is increased. Scanning Electron Microscopy (SEM) shows the grain particles become non-spherical and flakes when more vanadium substituted for nickel in the sample. Fourier Transform Infrared (FTIR) spectroscopy analysis and Energy dispersive analysis of X-Ray (EDAX) confirmed that NO3- impurities are not present and composition in samples Galvanostatic charge/discharge data obtained illustrates a discharge capacity of 80.57mAh/g LiNi0.8V0.1Al0.1O2 and an average of 80.55mAh/g for 10 cycles whereas LiNi0.6V0.3Al 0.1O2 highest discharge capacity is 80.52mAh/g and also an average of 80.53mAh/g for 10 cycles. Voltammographs of the LiNi0.8V0.1Al0.1O2, LiNi0.7V0.2Al0.1O2 and LiNi0.6V0.3Al0.1O2 materials showed good oxidation and reduction loop at 0.05mV/s and 1 mV/s scan rate.

Inhomogeneous distribution of chemical species in lithium nickel oxide cathode of lithium ion battery

The spatial distribution of the oxidation state for the nickel species in the LiNiO2 cathode was analyzed by means of the in-situ XAFS imaging technique during the charging and discharging processes. The inhomogeneous reaction for the LiNiO2 cathode was observed under the operating condition. The pattern in the 2-dimensional map of the oxidation state of the active material in the discharging process was similar to that in the charging process. It means that the areas preceding the discharging reaction agree with the areas delaying the charging reaction. It was suggested that the diffusion of Li+ was restricted by the surface product of the LiNiO2 electrode, and the concentration gradient of Li+ delayed the charging reaction at the reaction channel of the discharging reaction.

Use of sacrificial lithium nickel oxide for loading graphitic anode in Li-ion capacitors

The use of non-stoichiometric lithium nickel oxide, being a part of the activated carbon positive electrode in lithium-ion capacitors, is presented as an alternative to the use of metallic lithium for graphite pre-lithiation. During the first cycle, lithium ions are irreversibly extracted from the Li0.65Ni1.35O2 host structure and intercalated into the graphite negative electrode. Once extraction and pre-lithiation are completed, activated carbon becomes the only active material for electrical double-layer storage at the positive electrode, while reversible lithium intercalation occurs at the graphite negative one. Since the lithium ions extraction occurs at a potential of 4.2V vs. Li/Li+, electrolyte oxidation is prevented, and the cell displays a good cyclability in the potential range from 2.2V to 3.8V.

Safety Characteristics of Chemically Delithiated Cathode Active Materials

1. Introduction Lithium ion batteries are utilized for various applications, from small size battery for mobile phones and computers, to large scale energy source for automobile and stationary energy supply. It is necessary for lithium ion battery to be charged and discharged safely under any circumstance and usage, and various kinds of active materials have been studied for this purpose. Especially for large scale energy storage, thermal and structural stability of active materials is quite important. In this study, cathode active materials in their charged state are obtained by chemical extraction of lithium using NO2BF4 oxidizer, and by using those samples, we can evaluate the thermal and structural stability of cathode active materials alone without any interference of other electrode components such as carbon and binder additives. 2. Experimental Lithium has been chemically extracted from lithium nickel oxide (LiMeO2, Me = Ni0.80Co0.15Al0.05, NCA) with NO2BF4 in acetonitrile (1, 2). Chemical extraction of lithium has been carried out in a dry nitrogen-filled glove box in which the atmosphere is kept low levels of oxygen(～10 ppm) and water (dew point lower than – 55℃), respectively. LiMeO2 + NO2BF4 → Li(1-x)MeO2 + x LiBF4 + x NO2↑ Li(1-x)MeO2 with various values of lithium content can be obtained by controlling the reaction time with NCA and NO2BF4. The products after the reaction were washed by dry acetonitrile under same dry nitrogen atmosphere to remove LiBF4, and dried under vacuum at ambient temperature. The lithium concentration in the Li(1-x)MeO2 oxides were determined by atomic absorption. Thermal decomposition of the obtained samples is evaluated by monitoring oxygen generated during raising sample temperature by TPD-MS(temperature programmed desorption MS), and structural characterizations were also carried out with in situ X-ray diffraction and Raman spectroscopy. 3. Results anddiscussions Figure 1 shows the X-ray diffraction patterns of Li(1-x)MeO2 with different lithium content ( x= 0.23, 0.60, 0.63, 0.67, 0.70). The observed diffraction patterns can be indexed based on the R-3m space group and are consistent with the layered rock salt structure of a-NaFeO2. Diffraction peak of (003) shifts lower when the lithium extraction proceeds from x= 0.23 to 0.63, and shifts higher for the sample x = 0.67 and 0.70, which is the same tendency as electrochemically charged NCA (3). Oxygen generation behaviors of Li(1-x)MeO2 are shown in Figure 2. From all the samples, oxygen generation is detected around 270 ℃ and 400 ℃, and oxygen generation temperature decreases with increasing amount of lithium extraction from NCA. Oxygen generation at 270 ℃ is due to the structural change from the layered rock salt structure to spinel structure, and 400 ℃ is due to the structural change from spinel to rock salt structure. Addition to it, new peak of oxygen generation around 300 ℃ is observed for the sample x = 0.63 and 0.70. Large amount of lithium extraction possibly generates unstable structure, and the origin will be discussed in the presentation. References (1) I. Belharouak, W. Lu, D. Vissers, K. Amine., Electrochemistry Communications 8 (2006) 329–335 (2) S. Venkatraman, A. Manthiram., Solid State Ionics 176 (2005) 291–298 (3) Won-Sub Yoon a, Kyung Yoon Chung b, James McBreen a, Xiao-Qing Yang, Electrochemistry Communications 8 (2006) 1257–1262 Figure 1

Direct Dry Synthesis of LiNi0.8Co0.2O2 Thin Film for Lithium Ion Battery Cathodes

In recent years, a number of cathode materials have been investigated for lithium ion battery applications. Transition metal oxides like LiCoO2 [1-2], LiNiO2 [3-4] and LiMn2O4 [5-6] have attracted much attention from researchers due to their stability and capacity to intercalate Li. LiCoO2 is commonly employed in commercial batteries as an intercalation compound because of its easiness in synthesis, high theoretical specific capacity and good reversibility. However, high toxicity and high cost are associated with the use of Co. Lithium nickel oxide and lithium manganese oxide are two feasible replacement materials for lithium cobalt oxide, but they come with challenges and limitations as well. LiMn2O4 reacts with the electrolyte when the temperature exceeds 55 °C, leading to dissolution of manganese and the loss of capacity [7]. In the case of LiNiO2 cathodes, its capacity is irreversibly lost when nickel oxide transforms from the hexagonal to the cubic phase during the lithium deintercalation process [8]. This phase transformation can be prevented by partially replacing nickel with cobalt, thus LiNixCo1− xO2 (0 < x < 1) could enhance the stability while adding the benefits of higher reversibility and lower cost [9-10]. It is also found from literature that when x is approximately 0.2, this material demonstrates better cycling properties than other materials mentioned above [11-13]. While solid state reactions and sol-gel methods have been widely used to synthesize LiNi0.8Co0.2O2 powders, there are many problems associated with these processes, such as structural inhomogeneity, multiple time consuming steps, irregular morphology and poor control of the particle size [14-16]. Reactive spray deposition technology (RSDT), a one-step flame based deposition method, offers a convenient solution to electrode fabrication by direct deposition of LiNi0.8Co0.2O2 nanoparticles. Films can be grown directly on the current collector. RSDT has the capability to tailor the electrochemical properties of synthesized cathode materials by manipulating the several key processing conditions. The size, morphology, and composition of particles can be controlled by changing the reactant concentration in the solvent, the heat enthalpy of solvent, the flow rate of precursor solution, and the flow rate of oxidant gases. Precursor solution for flame combustion is prepared by dissolving acetylacetonates of lithium, cobalt and nickel into organic solvents like methanol. X-ray diffraction (XRD), transmission electron microscopy (TEM) and inductively coupled plasma (ICP) are used to characterize the chemical composition, crystal structure, and structural morphology of the synthesized LiNi0.8Co0.2O2 nanoparticles. Electrochemical properties of as-deposited LiNi0.8Co0.2O2 thin film are evaluated with typical 2032 coin half-cell using lithium foil as the counter electrode. As the particle size of cathode material is in the nanometer range, the diffusion length of lithium ions is small, which enables a fast charge and discharge rate. The large surface area of the nanoparticles can also reduce the resistance of charge transfer.

Electrochemical Behavior of Some Sodium Nickel Oxides for a Sodium-Ion Battery

Sodium-ion batteries have been considered as a cheap alternative to lithium-ion batteries. Electrode materials for a sodium-ion battery and a lithium-ion battery have interesting similarities and differences in materials characteristics and electrochemical properties. Layered lithium nickel oxide, LiNiO2 has been developed to achieve a high capacity battery, but it shows interslab cation mixing and poor thermal stability. Li2NiO2 has also been studied mainly as a cathode additive to compensate the lithium loss at the anode side owing to the SEI formation. It can provide a large irreversible charging capacity at the first cycle, but it exhibits a significant oxygen evolution upon charging. In this study, we report electrochemical properties of their sodium analogues for a sodium-ion battery. The materials were prepared via solid state reactions and characterized with powder XRD and SEM. Electrochemical properties of them are examined with coin half- and full-cells, and further characterized with ex-situ electrode XRD analysis. The experimental data was correlated to DFT+U calculations. Details on the materials and electrochemical properties will be presented at the meeting.

Direct Dry Synthesis of LiNi0.8Co0.2O2 Thin Film for Lithium Ion Battery Cathodes

In recent years, a number of cathode materials have been investigated for lithium ion battery applications. Transition metal oxides like LiCoO2 [1-2], LiNiO2 [3-4] and LiMn2O4 [5-6] have attracted much attention from researchers due to their good recharge capabilities. LiCoO2 is commonly employed in commercial batteries as intercalation compound because of its easiness in synthesis, high theoretical specific capacity and good reversibility. However, high toxicity and high cost are associated with this material. Lithium nickel oxide and lithium manganese oxide are two feasible replacement materials for lithium cobalt oxide, but they come with challenges and limitations as well. LiMn2O4 reacts with electrolyte when the temperature exceeds 55 °C, leading to the loss of capacity from the dissolution of manganese [7]. In the case of LiNiO2 cathode, its capacity can be irreversibly lost when nickel oxide transforms from hexagonal to cubic phase during the lithium deintercalation process [8]. This phase transformation can be prevented by partially replacing nickel with cobalt, thus LiNixCo1− xO2 (0 < x < 1) is proposed with the aim of improving the stability of cathode material, while adding the benefits of high reversibility and low cost [9-10]. It is also found from literature that when x is approximately 0.2, this material performs the best electrochemically [11-13]. While solid state reactions and sol-gel methods have been widely used to synthesize LiNi0.8Co0.2O2 powders, there are many problems associated with these processes, such as inhomogeneity, multiple time consuming steps, irregular morphology and poor control of the particle size [14-16]. Reactive spray deposition technology, a one-step flame based deposition method in ambient environment, offers a convenient solution to electrode fabrication by direct deposition of LiNi0.8Co0.2O2 nanoparticles onto the current collector to form a thin film. This technique has the capability to tailor the electrochemical properties of synthesized cathode materials by manipulating the processing conditions. The size, morphology, and composition of particles can be controlled via deposition parameters, including the reactant concentration in the solvent, the heat enthalpy of solvent, the flow rate of precursor solution, and the flow rate of oxidant gases. Precursor solution for the flame combustion is prepared by dissolving acetylacetonates of lithium, cobalt and nickel into organic solvent like methanol. X-ray diffraction (XRD), transmission electron microscopy (TEM) and inductively coupled plasma (ICP) are used to characterize the chemical composition, crystal structure, and structural morphology of the synthesized LiNi0.8Co0.2O2 nanoparticles. Electrochemical properties of as-deposited LiNi0.8Co0.2O2 thin film are evaluated with typical 2032 coin half-cell using lithium foil as the counter electrode. As the particle size of cathode material is in the nanometer range, the diffusion length of lithium ions is small, which enables a fast charge and discharge rate. The large surface area of the nanoparticles can also reduce the resistance of charge transfer. In order to further investigate the electrochemical performance of the material, a coin full-cell using graphite as the anode is tested.