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A fuel cell in development for use in unmanned aerial vehicles is simulated and presented. The fuel primarily cell tackles the issue of weight for unmanned aerial vehicle applications. The balance of plant is also significantly reduced by this fuel cell which reduces weight and makes the fuel cell system more compact. Simulations include fluid flow, electrochemical effects, concentrated species transport, and heat distribution. The polarization plot produced by the simulation is in good agreement with experimental results.

Current-sensing Atomic Force Microscopy (CS-AFM) and Nano-scale Impedance Spectroscopy (NIS) are key characterization tools in the research and development of diverse materials systems. These have been used in fuel cell research to distinguish between various sources of cell losses; for example, ohmic losses in the electrodes and electrolytes, activation over-potentials due to reaction kinetics, and mass transport effects. Proton transport and water diffusion phenomena are locally observed to determine the ionic channel structure and mechanism.

The PEMFC (Polymer Electrolyte Membrane Fuel Cell) and DMFC (Direct Methanol Fuel Cell) are very similar in their concept and design however, their outputs are very different. The PEMFC is more expensive because current technology does not allow for easy access of hydrogen gas. It has a much higher power output than the DMFC. This makes it more suitable for tasks like powering a vehicle or being used as a UPS. It has even been proposed to power remote areas that don’t have easy access to the grid. The DMFC has a lower power output but, a higher energy density. This means that although it cannot put out a lot of power at one time, it can do it for an extended period. This fuel cell has been proposed for tasks such as a cell phone battery, laptop battery, etc. One of advantages of DMFC is its ability to rapidly recharge and it is a very attractive portable battery.

The mechanical benefits gained from using carbon nanotubes in liquid thermosetting resins gives stereolithograhy 3-D printing a promising future in the world of additive manufacturing. There are some challenges faced with obtaining consistent results in this area of research, however. The primary reason is due to the unique aspect ratio of the carbon nanotubes which leads to uneven distribution during the preparation of the polymer matrix composite. Furthermore, it is also difficult to achieve complete photo-polymerization of the part due to the carbon nanotubes interference with the UV light during the curing process. Here the effect of MWCNT filler on mechanical strength and stiffness of 3-D printed polymer-matrix composite using stereolithography printer is studied. MWCNTs were de-agglomerated in Toluene and introduced into photopolymer resin at various weight loadings. 3-D printing was performed with the composite resin followed by uniaxial tensile testing to obtain data to analyze for possible mechanical stress and strength benefits. This work concluded that the addition of .005 weight % of MWCNT showed an improvement of 24.8 % and 9.6 % for stress failure and Young’s Modulus respectively compared to neat sample. The addition of 0.01 and 0.02 weight % had adverse effects of lowering the Young’s Modulus and causing stress failure.

There has been a significant rise in the use of stainless steel structures, especially because of its improved corrosion resistance properties in natural water when compared to carbon steels. However, also there has been reports of corrosion failures in these steels especially at weld points and other heat affected zones, some of which can have large scale socio-economic consequences. Coatings with nanomaterials have been proposed to stabilize the surface and prevent the failure. 2 dimensional (2D) materials e.g. graphene has recently elicited a lot of interest due to their improved corrosion resistance properties. This work investigates the corrosion resistance properties of a commercial grade stainless steel in 3.5 wt. % aqueous NaCl solution, coated with 3 different types of 2D nanomaterials; molybdenum disulfide (MoS2), boron nitride (BN) and tungsten disulfide (WS2). Coatings of these materials on the tested stainless steel were made via drop casting method from a previously prepared slurry of each. The electrochemical behavior of the coated stainless steel was studied with bare stainless steel as control, using open circuit potential and Tafel plots. The MoS2 coated stainless steel displayed a superior corrosion resistance than the BN and WS2 coated stainless steel samples. Scanning electron microscopy (SEM) images demonstrate uniform coating for the MoS2 coated stainless steel sample, which provides a reduced number of defect sites for diffusion of corrosive ions and explains its superior corrosion resistance compared to the other coated samples It is postulated that MoS2 showed a higher corrosion resistance vis-à-vis the bare sample due to its higher open circuit potential as well as a lower corrosion rate.

With the existing drawbacks of the Li ion batteries (LIBs) in terms of expenditure and safety, there is an increasing research focus on Na ion batteries (NIBs) as a viable replacement especially for large scale grid storage applications. Considering the rather bulky Na ion and the challenges it would pose for efficient reversibility, choice of optimum electrode materials is of significance. Among the various types of materials being considered for applications as the negative electrode, 2-dimensional (2D) transition metal dichalcogenides (TMDs) have elicited interest due to their layered structure and existing in a range of compositions. Among the various TMDs that have been studied, MoS2 has received the most focus due to its excellent cyclability as well as stability, however, others in the TMD family have not received as much focus. In this work, we study the sodium recycling properties of exfoliated TMD (MoSe2, WSe2 and MoTe2)- reduced graphene oxide (rGO) composite. Electrochemical analysis was performed by using the TMDs in coin cells with Na foil being the counter electrode in organic electrolyte within a cycling window of 2.25 V – 10 mV. Cell cycling results have indicated that WSe2 electrode performed the best and provided a reversible capacity more than 250 mAhg-1 whereas pristine rGO demonstrated only about 80 mAhg-1. Also, all the TMD/rGO composite electrodes demonstrated a first cycle efficiency greater than 50 %. Similarly, capacity retention results demonstrate a similar pattern, with WSe2 exhibiting about 80 % capacity retention followed by MoSe2 (∼60 %) and MoTe2 (∼45%). Results in aqueous media exhibit similar trends. In conclusion, it can be said that different 2D layered TMDs have shown promise for application as negative electrodes in NIBs in organic and aqueous environment. This provides hope in their extensive application as stable, high reversible capacity negative electrode materials in NIBs.

1. Introduction – Secondary Li ion batteries, regarded as the current benchmark for new battery technologies, are under extensive development throughout the world [1]. However, their requirement that organic electrolytes be used limits the rate capacity and specific power the cell can achieve and present several safety hazards and cost limitations that prevent their application in medium to large-scale storage systems [1, 2]. Here, aqueous rechargeable lithium ion batteries (ARLBs) utilizing mesoporous spinel metal oxide cathodes are investigated, due to their high capacity, cycling stability and high rate capability [3, 4]. 2. Fabrication procedures – LiMn2O4 (LMO) anode is fabricated by solid state reaction of 5 mmol Li2CO3 and 10 mmol Mn2O3 at 750 °C for 24 hrs. Activated carbon (AC, Kureha BAC) is utilized as received. Electrochemical testing was performed on Teflon sealed CR2032 coin cells utilizing type 304 S.S. mesh as electrode substrates. 6 M LiNO3 in D.I. water is used as the electrolyte, with addition of 0.01 M HNO3 and LiOH to create acidic and basic electrolytes, respectively. 3. Experimental setup and results – Average mass loadings of 5 mg cm-2 are utilized. Charge and discharge is done at a rate of 2 mA cm-2 between potentials of 0 and 2 V. HiRes TEM images, EDX spectrum and discharge capacity results of three LMO based cells are shown in Figure 1(a-d). Evidence of the pH dependence of the development of a porous nanoscale layer of Fe2O3 is shown in Figure 1(a-c), and is reflected in the superior performance of the basic cell, as shown in Figure 1(d). Capacity fading characteristic of the development of mixed material phases and Jahn-Teller distortion is observed in the two cells that do not show the development of this porous Fe2O3 layer (acidic and neutral), while the introduction of the new coating creates a capacity increase of ~ 50 % with high stability up to 500 cycles. 4. Conclusions – Influence of the creation of a porous nanoscale Fe2O3 layer on the LMO cathode is directly responsible for observed increases in cell discharge capacity and the stabilization of material capacity fade, greatly increasing the performance of both functional indicators. Future work aims to develop an inexpensive and efficient way to create mesoporous and nanoporous microstructures of Fe2O3 and other spinel metal oxides with high porosity and active surface area, thereby increasing material capacity and rate capability of ARLBs required by medium and large scale energy storage. 5. References – [1] G.X. Wang, S. Zhong, D.H. Bradhurst, S.X. Dou, H.K. Liu, Journal of Power Sources, 74 (1998) 198-201. [2] X. Zeng, Q. Liu, M. Chen, L. Leng, T. Shu, L. Du, H. Song, S. Liao, Electrochimica Acta, 177 (2015) 277-282. [3] W. Tang, S. Tian, L.L. Liu, L. Li, H.P. Zhang, Y.B. Yue, Y. Bai, Y.P. Wu, K. Zhu, Electrochemistry Communications, 13 (2011) 205-208. [4] J. Zhang, T. Huang, Z. Liu, A. Yu, Electrochemistry Communications, 29 (2013) 17-20. Figure 1

1. Introduction – Lithium manganese oxides (LMO) based spinels are important cathode materials for Lithium ion batteries (LIBs). However the primary problem of these electrodes are that they suffer structural deformation owing to the Jahn-Teller distortion[1]. This reduces their lifetime and the efficiency of the battery greatly reduces with cycling. However, some improvement have been obtained by adding transition metals and/or modifying the surface area of the electrode materials. This abstract focuses on developing novel porous Ni and Al based LMO microstructures for LIB applications[2]. 2. Experimental fabrication – The LMO fabrication is done from their precursors. Initially MnCO3 microspheres are obtained from NaHCO3 and MnSO4.H2O precursors. This reaction is done in the liquid phase and once the two precursors are mixed, immediate formation of a white precipitate is noticed. Once this is obtained, the MnCO3 hollow spherical precursors are then reacted with LiOH by solid state reaction technique in stoichiometric amounts to obtain the LiAl0.1Mn1.9O4 (LAMO) and LiAl0.1Ni0.1Mn1.8O4 (LANMO) microspheres. 3. Results –Charge-discharge analysis have been performed at a constant current density of 0.5 mAcm-2by an Arbin instrument up to 4.5 V and discharged to 2V. The discharge curves follow the characteristic pattern of the LMO spinel based compounds. A phase changes is noticed during the discharge process, at ~ 4.1 V and ~ 2.75 V corresponding to the kink in the discharge. The second phase change at ~ 2.75 V is due to theJahn-Teller effect which produces a permanent deformation of the crystal lattice and steady loss of capacity. The maximum discharge capacity of the LAMO sample is 122.51 mAhg-1 and 75th cycle discharge capacity is 42.22 mAhg-1. The LANMO sample provides a 1st cycle discharge capacity of 140.49 mAhg-1 and a 75th cycle discharge capacity of 66.24 mAhg-1. The LANMO system is seen to be superior in performance as compared to the LAMO system. This is due to the stabilizing role that the added Ni has provided to the crystal lattice, improving the cathodes ability to perform stable intercalation. The performance of these electrodes is demonstrated in Figure 1(a-c). 4. Conclusions – This research provides an insight in to the study of spinels at relatively low voltages which is not so prevalent in the literature. Also a novel technique is used to produce highly porous LMO based spinel spheres which serve to have enhanced electrochemical capacity and cell performance. References: [1] B.J. Hwang, R. Santhanam, D.G. Liu, Y.W. Tsai, Journal of Power Sources, 102 (2001) 326-331. [2] R. Thirunakaran, B.R. Babu, N. Kalaiselvi, P. Periasamy, T.P. Kumar, N.G. Renganathan, M. Raghavan, N. Muniyandi, Bulletin of Material Sciences, 24 (2001) 51-55 Figure 1

1. Introduction – Secondary Li ion batteries, regarded as the current benchmark for new battery technologies, are under extensive development throughout the world [1]. However, their requirement that organic electrolytes be used limits the rate capacity and specific power the cell can achieve and present several safety hazards and cost limitations that limit their application in large-scale storage systems [1, 2]. Here, aqueous Li ion cells utilizing LiMn2O4 spinel compound anodes is investigated, due to its ample capacity, cycling stability and high rate capability [3]. 2. Fabrication procedures – LiMn2O4 (LMO) anode is fabricated by solid state reaction of 5 mmol Li2CO3 and 10 mmol Mn2O3 at 750 °C for 20 hrs. Li2Mn4O9 cathode is fabricated by solid state reaction of 10 mmol LiOH·H2O and 20 mmol MnCO3 at 380 °C for 24 hrs. LiMn2O4 solid microspheres were prepared by calcination of LiOH·H2O and MnCO3 microspheres at 650 °C for 3 hrs in air. MnCO3 solid microspheres were prepared as follows: 1 mmol MnSO4·H2O and 1 mmol NaHCO3 were dissolved separately in 70 ml of distilled water. 7 ml of ethanol was added to the MnSO4 solution under stirring. Direct mixing of the NaHCO3 and MnSO4 solutions is done, and precipitate is allowed to form overnight. MnCO3 microspheres were obtained from multiple centrifugation and washing cycles. Obtained product was allowed to dry overnight at 100 °C in air. Activated carbon (AC, Kureha BAC) is utilized as received. 3. Experimental setup and results – XRD spectra of the solid state LiMn2O4 anode (LMO¬_SS) and LiMn2O4 solid microspheres (LMO_Sμ) are shown in Figure 1(a). SEM image of the LMO solid microspheres is shown in Figure 1(b). Cycling performance of LMO_SS vs. Li2Mn4O9 in 6M LiCl (pH 12, 0.01 M LiOH) is shown in Figure 2. 1st discharge capacities and charge voltage plateaus of cells utilizing LMO_SS vs. AC in 6M LiCl with varying pH is shown in Figure 3. Charge currents of 1.5 mA cm-2 and discharge currents of 0.25 mA cm-2 are used for all cell tests. 4. Conclusions – An initial decrease in discharge capacity of the LiMn2O4 and Li2Mn4O9 cell is observed from the 1st to 20th discharge cycle. The discharge capacity of the cell is observed to asymptotically approach 60 mAh/g by the 100th cycle. Discharge voltage and capacity of the LMO and AC cell is observed to be greatly dependent on electrolyte pH. A voltage plateau during is observed during charging that did not contribute to cell discharge capacity. Future work aims to investigate the processes occurring at the anode during the observed charge voltage plateau as well as the change in charge transfer kinetics and cell capacity when employing both solid and hollow LiMn2O4 microspheres as the active anode. Due to the dissolution tendencies of Mn in aqueous electrolyte, methods of increasing cell cycling stability are also of interest. 5. References – [1] G.X. Wang, S. Zhong, D.H. Bradhurst, S.X. Dou, H.K. Liu, Journal of Power Sources, 74 (1998) 198-201. [2] X. Zeng, Q. Liu, M. Chen, L. Leng, T. Shu, L. Du, H. Song, S. Liao, Electrochimica Acta, 177 (2015) 277-282. [3] W. Tang, S. Tian, L.L. Liu, L. Li, H.P. Zhang, Y.B. Yue, Y. Bai, Y.P. Wu, K. Zhu, Electrochemistry Communications, 13 (2011) 205-208. Figure 1

1. Introduction – Transition metal oxides are considered to be promising as anode materials for sodium ion batteries (SIB) [1, 2]. Among them tin oxide has attracted attention because of its high theoretical capacity, however the capacity drops steadily in the subsequent cycles due to large volume change [3]. A novel solvoplasma technique to produce SnO2 NWs as anode for SIBs is studied. 2. Fabrication procedures – A novel solvoplasma based technique is used to produce the SnO2 NWs. The precursor materials are a 1:1 ratio of micro-sized SnO2 particles and KOH pellets thoroughly ground together. The paste is held for about 2 minutes in a plasma arc which is operates at a power of 1000 W – 2000 W and an a.c. frequency of 2.5 GHz. SnO2 NWs such obtained are impure (containing K2SnO3) and need to be further purified. The purification is done by repeated centrifugation with DI water, thoroughly ground and finally treated with 50 ml of 0.1 M HCl for an hour. Once this is done, the NWs are retrieved and calcined in an oven at 550 ᵒC for 12 hours. The SnO2 NWs are tested against a Na metal foil and NaClO4 electrolyte mixed with ethylene carbonate and propylene carbonate (EC and PC ratio being 1:1). 3. Results – XRD spectra of the impure SNO2 and pristine SnO2 are shown in Figure 1 below. As can be seen, the impure or as-made SnO2 sample contains some K2SnO3 peaks as well. However, the purification process is effective and the pure sample contains no K2SnO3 impurity. The SEM image of the impure and the pristine SnO2 samples are shown in Figure 2(a) and (b) respectively. As can be seen from the images, very well defined nanowires are obtained by the solvoplasma process. Figure 2(b) shows the NWs to be slightly bulged in morphology, this can be attributed to the cleaning process. The first discharge cycle for the two electrodes are shown in Figure 3 below. As can be seen the pristine SnO2 performs much better than the impure SnO2 sample, providing a specific capacity of 280.48 mAh/g as against 160.29 mAh/g of the impure sample. The cleaning process helps to remove the K+ ions and free up the pores for Na intercalation to take place. 4. Conclusions – A novel scalable technique is described to produce pristine and highly crystalline SnO2 NWs starting from rather inexpensive and easily available precursors. However the SnO2 NWs produced are impure and have K2SnO3 which are removed via an HCl based cleaning process which frees up the interstices of the SnO2 NWs from the K+ ions and improves Na+ intercalation. The manifestation of this is seen in the galvanometric discharge cycles where the pristine SnO2 shows a much higher capacity. The goal of the work remains to show that these NWs will provide a great degree of stability and not suffer from considerable capacity fading due to their crystallinity and purity. 5. References – [1] L. Wang, K. Zhang, Z. Hu, W. Duan, F. Cheng, J. Chen, Nano Research, 7 (2014) 199-208. [2] D. Su, G. Wang, ACS Nano, 7 (20133) 11218-11226. [3] Y. Wang, D. Su, C. Wang, G. Wang, Electrochemistry Communications, 29 (2013) 8-11. Figure 1

1. Introduction – Sodium batteries are being studied to overcome the drawbacks of Li ion based batteries viz. cost, poor cycle life of Li etc. [1]. Layered compounds are finding applications as anodes and cathodes as these are able to intercalate the large sized Na+ ion better [2]. Prussian blue and layered transition metal oxides are the compounds of choice to facilitate easy intercalation, increase cell performance and provide higher specific capacities [3, 4]. The TiO2 based anodic system is analyzed from different aspects to obtain the optimum system in this case. 2. Fabrication procedures – Fabrication process for the prussian blue cathode involves dissolution of 3 m mol of Na4Fe(CN)6.10H2O in 40 ml of 0.1 M conc. HCl solution followed by vigorous stirring at 500 rpm for 5 minutes. Once this is done, the resulting solution is dried at 80 °C for 20 hours. For the anode, the crystalline TiO2 anatase and the amorphous TiO2 rutile powder are used as obtained. Na2Ti3O7 is obtained by heating 1g of TiO2 and 0.36 g of NaOH at 750 °C for 20 hours, after they were mechanically milled for 4 hours. 3. Experimental steps and results – The various characterization procedures are as follows: (i) Analysis of the phase of the TiO2 and Na2Ti3O7 anode. Figure 1 shows the XRD data of TiO2 (blue, bottom) and Na2Ti3O7 anodes (orange, top). The main peaks are seen and no impurities peaks are noticed, especially in the Na2Ti3O7 sample which indicate phase formation is complete. (ii) Analysis of the Prussian blue cathode before and after the cell cycling to show the degradation of the cathode. The graph in figure 2 represents the XRD data of the pristine Na-PB cathode (bottom, in blue) and the cathode after 10 cycles of operation (top, in orange). The post cycling XRD graph shows the presence of the peaks in the same position indicating very little structural damage. (iii) Cell cycling is performed in a 2 electrode set-up within in an aqueous electrolyte in a voltage range 0 V to 0.7 V. Figure 3 gives the specific capacity with respect to the voltage for the 1st, 2nd, 5th and 10th cycles respectively. The open circuit voltages can be seen to be approximately around slightly higher than 0.55 V and a maximum specific capacity of 76.52 mAh/g. It is also seen that the graphs are very close to one another which indicate very little capacity fading. (vii) Comparison of the stability behavior of different TiO2 anodes. Figure 4 shows the stability characteristic of the different TiO2 based anode systems. As can be seen, the Na2Ti3O7 system is the most stable whereas the amorphous system demonstrates the least stability. 4. Conclusion & future work – Sodium rich prussian blue system has been tried out as a positive electrode versus a transition metal oxide e.g. TiO2 as the negative electrode. The TiO2 system has been tried from different aspects (crystalline, amorphous, heat treated and heat treated) and the imporrtant structural aspects and cell performances have been discussed. Future work would involve analysis if the corrosion mechanism at the electrode-electrolyte interface and study of the Prussian blue cathode in greater detail. References: [1] M.S. Islam, C.A.J. Fisher, Chemical Society Reviews, 43 (2014) 185-204. [2] D. Kim, E. Lee, M. Slater, W. Lu, S. Rood, C.S. Johnson, Electrochemistry Communications, 18 (2012) 66-69. [3] A.A. Karyakin, Electroanalysis, 13 (2001) 813-819. [4] Y. Yue, A.J. Binder, B. Guo, Z. Zhang, Z.-A. Qiao, C. Tian, S. Dai, Angewandte Communications, 53 (2014) 3134-3137. Figure 1

1. Introduction – Lithium-ion batteries are regarded as the current benchmark for new battery designs. While lithium-ion batteries offer both high energy densities and large cell potentials, they also possess many inherent disadvantages such as flammability and high material costs [1, 2]. Potassium-ion (K+) batteries can be of great environmental and economic importance. Potassium possesses an oxidation/ reduction potential closest to lithium among all alkali metals, only 0.12 V lower than that of lithium [3]. Furthermore, nanoscale coatings of transition metal oxides are known to behave as inhibitors to cell capacity degradation [4]. 2. Fabrication procedures – Prussian blue (Fe4[Fe(CN)6]3) cathode is fabricated by dissolution of 4 mmol K4Fe(CN)6•3H2O in 50 ml of 0.1 M HCl solution followed by vigorous mixing at 500 rpm at 80 °C overnight until dry. Resulting powder is ground, washed and separated by centrifugation and at 80 °C overnight. α MoO3 anode is fabricated by titration of 0.7 mmol (NH4)6Mo7O24•4H2O in 10 ml of 5 M (NH4)2CO3 with Nitric acid until a white precipitate is formed. Solution is aged overnight, dried at 80 °C, washed with HCl solution and separated by centrifugation, and then annealed at 500 °C for 20 hrs. Electrolyte of 0.5 M aqueous KPF6 is used. Atomic Layer Deposition technique is used to deposit thin TiO2 films of 5 and 10 nm on the Prussian blue cathode surface. 3. Experimental setup and results –XRD and SEM is done to study the crystallinity and morphology of both pristine and TiO2 coated cathodes. XRD spectrum of Prussian blue cathode and α-MoO3 anode is shown in Figure 1. Cycling performance is studied using a charge/discharge current of 2 mA and 0.5 mA respectively and voltage range of 0 to 1 V. Discharge capacity and capacity retention performance of aqueous cells of pristine, 5 nm and 10 nm TiO2 coated Prussian blue cathodes and α MoO3 anode is shown in Figures 2 and 3 respectively. 4. Conclusions and future work – A decrease in initial discharge capacity and increase in capacity retention is observed for cells utilizing a TiO2 coated cathode. Initial discharge capacities of the 5 nm and 10 nm TiO2 coated cathodes are observed to be less than that of the pristine cathode. After 10 cycles all three cell configurations are observed to approach approximately the same discharge capacity. Both TiO2 coated cathode materials show considerable increase in capacity retention with respect to the pristine cathode. Future work aims to increase cell capacity by post-fabrication modification of anode and cathode. Post-cycling changes in electrode structure and morphology are also of interest. 5. References – [1] D. Lisbona, T. Snee, Process Safety and Environmental Protection, 89 (2011) 434-442. [2] M.D. Slater, D. Kim, E. Lee, C.S. Johnson, Advanced Functional Materials, 23 (2013) 947-958. [3] A. Eftekhari, Journal of Power Sources, 126 (2004) 221-228. [4] X. Li, J. Liu, X. Meng, Y. Tang, M.N. Banis, J. Yang, Y. Hu, R. Li, M. Cai, X. Sun, Journal of Power Sources, 247 (2014) 57-69. Figure 1

1. Introduction – Solid state batteries overcome many of the essential drawbacks of liquid electrolyte batteries, such as liquid electrolyte and leakage issues [1]. Another major issue is the degradation of the Li based cathode from continuous cycling due to a change in its microstructure [2]. Nanoscale coatings are thought to prevent the degradation of the cathode by acting as a protective layer on its surface [3, 4]. This paper studies the performance of lithium cobalt oxide (LCO) based cathodes with and without protective coatings of Al2O3 and TiO2. 2. Fabrication procedures – Fabrication procedures entail the following stages: (i) Making the liquid lithium lanthanum tantalite (LLTO) electrolyte by a sol gel technique from its precursors and then vaporizing the liquid by exposing it to elevated temperature. The paste left behind is thoroughly dried and finely ground and is included as the solid state electrolyte. (ii) The cathode is made by thoroughly grinding lithium cobalt oxide (LCO) powders and then making slurry by mixing them thoroughly with PTFE binder, carbon powder, and alcohol. Pasted on to a stainless steel foil, this whole system acts as the cathode. (iii) The Atomic Layer Deposition (ALD) technique is used to deposit thin films (~6 nm) on the surface of the LCO cathodes to compare them with the pristine cathodes. (iv) The anode includes Li metal foil. Once this is complete, the three separate components are assembled into a coin cell. 3. Experimental steps and results – The characterization procedures are as follows: (i) XRD and SEM study to check the phase of the solid state LLTO electrolyte, pristine LCO cathode, and cathodes with Al2O3 and TiO2 coatings and the surface morphology. Figure 1 shows the XRD data of the LCO cathode with TiO2 deposition. The main Al2O3 peaks are seen and no TiO2 peaks are obtained, indicating the amorphous nature of the deposition. (ii) TEM and XPS analysis to study the nature and actual thickness of the coating. This will give an idea about the actual depth of the deposition as well as the nature of electronic bonding at the surface. From Figure 3 it may be seen that reduction potential shifts more to the right for the TiO2 coated cathode. The greater ΔV value exhibited by the coated cathode indicates greater energy needed for the reduction reaction owing to the deposition, and TiO2 has the highest ΔV value. Figure 2 represents the XPS data of the LCO cathode coated with Al2O3, showing clearly the Al 2s and 2p and the O 1s peaks. (iii) Cyclic voltammetry is performed within a voltage range of 3 V to 4.5 V and the applied current is 5 mA/s. (iv) Cyclical performance of the cell. Figure 4 shows that open circuit voltages are obtained of slightly less than 3 V for a current density of 10 mA/cm2, compared with 3.259 V and 3.312 V, respectively, for i = 30 mA/cm2 and 40 mA/cm2 for the LCO pristine cathode. 4. Conclusion – Amorphous transition metal oxide coatings have been tried out. XPS data have shown the formation of the thin film. A rightward shift in the reduction potential demonstrated by the CV data indicates greater energy necessary which is a measure of the protective nature of the coating. Future work includes studies of the cycling performance of the cell with the coated cathodes. References: [1] M.V. Tyufekchiev, S. Hur, Developing a Low-Cost Methodology for Fabricating All-Solid-State Lithium-Ion Battery, in: Chemical Engineering, Worcester Polytechnic Institute, 2013. [2] M. Ogawa, K. Yoshida, K. Harada, Environment, Energy and Resources, 88-90. [3] X. Li, J. Liu, X. Meng, Y. Tang, M.N. Banis, J. Yang, Y. Hu, R. Li, M. Cai, X. Sun, Journal of Power Sources, 247 (2014) 57-69. [4] H. Zhao, L. Gao, W. Qiu, X. Zhang, Journal of Power Sources, 132 (2004) 195-200.

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