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To boost the circular economy of the electric vehicle battery industry, an accurate assessment of the state of health of retired batteries is essential to assign them an appropriate value in the post automotive market and material degradation before recycling. In practice, the advanced battery testing techniques are usually limited to laboratory benches at the battery cell level and hardly used in the industrial environment at the battery module or pack level. This necessitates developing battery recycling facilities that can handle the assessment and testing undertakings for many batteries with different form factors. Towards this goal, for the first time, this article proposes proof of concept to automate the process of collecting the impedance data from a retired 24kWh Nissan LEAF battery module. The procedure entails the development of robot end-of-arm tooling that was connected to a Potentiostat. In this study, the robot was guided towards a fixed battery module using visual servoing technique, and then impedance control system was applied to create compliance between the end-of-arm tooling and the battery terminals. Moreover, an alarm system was designed and mounted on the robot’s wrist to check the connectivity between a Potentiostat and the battery terminals. Subsequently, the electrochemical impedance spectroscopy test was run over a wide range of frequencies at a 5% state of charge. The electrochemical impedance spectroscopy data obtained from the automated test is validated by means of the three criteria (linearity, causality and stability) and compared with manually collected measurements under the same conditions. Results suggested the proposed automated configuration can accurately accomplish the electrochemical impedance spectroscopy test at the battery module level with no human intervention, which ensures safety and allows this advanced testing technique to be adopted in grading retired battery modules.

In this paper new experimental data are presented on the rate of carbon dioxide absorption from a synthetic flue gas (67 vol% N2, 18 vol% O2 and 15 vol% CO2) in a rotating packed bed. The bed had an inner diameter of 80 mm and an outer diameter of 300 mm and operated at speeds of 600 – 1450 rpm. The packing used was Expamet stainless steel mesh. The novelty of this work is that the gas phase was saturated with water vapour at 40˚C, as would be the case in CO2 capture from flue gas. Other investigations on carbon capture using a rotating packed bed reported in the literature have used dry gases. The solvents used in the experiments were monoethanolamine (MEA) solutions containing 30mass% MEA and 90mass% MEA. The rate of absorption was measured by analysing the CO2 content of the gas phase at the inlet and outlet of the rotating packed bed using an online CO2 meter. The pressure drop, power consumption and temperatures of the gas and liquid phases were measured as well. The measured overall gas phase mass transfer coefficient (KGa) was found to be in agreement with similar measurements from literature and ranged in value from 1.8 - 6.2 s-1. The concentration of MEA was found to have the largest effect on KGa followed by the liquid to gas mass flow ratio and the rotational speed.

In Electric vehicles, the Li-ion battery reaches its end of life when the capacity is decreased to 80% of the initial rated capacity. However, a battery with only 20% used capacity does not mean the battery cannot be used in a secondary application with less current demand, in a controlled and secure environment. This necessitates a comprehensive understanding of the configuration of the end of life (EoL) batteries in module and pack level, in terms of inconsistencies in capacity and impedance of the cells forming the module and hence the battery pack. Accordingly, a safer and longer second life use can be granted. This paper investigates the impact of parallel connection on the impedance and capacity of four, pouch lithium-ion cells forming a battery module in 2P 2S configuration. The energy storage capacity and the AC impedance of each parallel pair and individual cells are recorded and compared. The results highlight that the capacity loss due to the parallel connection is 6% less than the sum of the individual capacity for each cell. With the help of a developed equivalent circuit model, the ohmic resistance of the pair and cell is estimated to demonstrate the contribution of interconnections in increasing the total impedance and hence the perceived loss of capacity in the parallel connection.

This paper reports a systematic study of the codoping of SnO2 with Sb and Ni to identify the mechanism responsible for the electrocatalytic generation of ozone on Ni/Sb-SnO2. On the basis of interpretation of a combination of X-ray diffraction, BET surface area measurements (N2), and thermal analysis, the formation of ozone appears to take place on particle surfaces of composite Sb-SnO2 grains and is controlled by diffusion of OH along internal crystallite surfaces within the grain. Sb-doped SnO2 is inactive with respect to ozone evolution in the absence of Ni, demonstrating a synergic interaction between nickel and antimony. From X-ray photoelectron spectroscopy (XPS) investigations, Sb(V) ions substitute for Sn(IV) in the lattice with a preference for centrosymmetric coordination sites, while the Sb(III) ions occur at grain surfaces or boundaries. Ni was not detected by XPS, being located in the subsurface region at concentrations below the detection limit of the instrument. In addition to identificatio...

Rotating packed beds (RPB) are an intensified alternative to conventional absorption columns. RPBs could substantially reduce costs associated with reactive-absorption processes, such as post-combustion CO2 capture. This study presents internal radial pressure profiles obtained experimentally from inside a rotating packed bed. This approach allows the individual contributions to the overall pressure drop to be investigated in greater detail than previous studies. Experiments examined the effect of rotation speed, gas flow and liquid flow on pressure drop in RPBs. The result illustrated the pressure drop can be described well using a simple 1D pressure drop contribution model. The casing pressure drop is due in part to a free vortex that forms in the RPB eye, along with entrance and exit losses. This result improves understanding of gas pressure drop, and how these factors affect the performance and design of full-scale RPBs.

Nanoparticulate SnO2 produced by a hydrothermal method was characterised by BET, XRD, TGA-MS and in situ variable temperature diffuse reflectance infra red spectroscopy (DRIFTS) to determine the surface behaviour of water. For the (100) facets, hydrogen bonding does not occur, and water adsorption is less strong than for the (111) and (110) facets where hydrogen bonding does occur. Reversible uptake of oxygen was observed. These findings have implications for other surface-gas reactions in which Ni and Sb co-doped SnO2 (NATO) anodes are used for ozone generation. BET showed the relatively high surface area and nanometer scale of the SnO2 particles, whilst XRD confirmed the nano dimension of the crystallites and showed only the cassiterite phase. TGA analysis indicated four temperature regions over which mass loss was observed. These and the in situ DRIFTS studies revealed the existence of various forms of water associated with specific crystal facets of the SnO2, as well as the existence of isolated O-H groups and adsorbed oxygen species. Electronic absorptions were also observed and the data rationalised in terms of the existence of both free electron absorptions, and absorptions from oxygen vacancy states. The role of adsorbed molecular oxygen in electrochemical ozone generation at Ni and Sb co-doped SnO2 (NATO) anodes was strongly suggested by this work.