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As the electrification of the transport sector progresses, an abundance of lithium-ion batteries inside electric vehicles (EVs) will reach their end-of-life (EoL). The cells inside battery packs will age differently depending on multiple factors during their use. Currently, there is limited publicly available research on the degradation of the individual cells recovered from real-world EV usage. Once they have been recovered from the vehicle, large-format pouch cells are challenging to characterise, measure their internal structure and determine state-of-health (SoH). Here, large-format (261 x 216 x 7.91 mm) Nissan Leaf cells are harvested from an EV and four complementary non-destructive techniques are used to distinguish the ageing of cells arranged in varying orientations and locations within the pack. The measurement suite includes infrared thermography, ultrasonic mapping, X-ray computed tomography, and synchrotron X-ray diffraction, and represents a unique combination of characterisation techniques. We found that each of the non-destructive diagnostic techniques corroborated each other yet provide different complementary insights. The influence of orientation and location of the cells is significant, with the rotated/vertically aligned cells differing significantly from the flat/horizontally aligned cells in mode and degree of ageing. These insights provide new information on cell degradation that can help to influence pack design and illustrates how rapid and relatively inexpensive technology can provide sufficient information for practical assessment compared to costly synchrotron studies. Such an approach can inform decision support at EoL and more efficient battery production reducing the wastage of raw materials.

Nickel-antimony doped tin oxide (NATO) catalyst has greatly considered its capability to treat high organic matter and eliminate colour in wastewater as palm oil mill wastewater with electrochemical ozone generation. This study presents the optimal Ni content of NATO and its properties to enhance ozone generation. The NATO anodes were fabricated by dip-coating, varying the Ni content between 0.5% and 5%. The key findings show that all anodes showed a single phase of rutile structure with the cracked mud on the surface. The binding energies of the Sb3d3/2 peak at 540.48 eV and 541.58 eV agree with Sb3+ and Sb5+, respectively. The optimal ozone current efficiency of 37% at the current density of ca. 0.22 A cm-2 in 0.5 M H2SO4 at 2.7V was obtained on the NATO anode with 2% Ni content calcined at 700 oC. The palm oil mill wastewater treatment result showed that decolourisation TOC and COD removal efficiency increased with increasing electrolysis time. The colour removal efficiency achieved was more than 85% for a reaction time of 15 min. The efficiency of TOC and COD removal was reached ca. 80% in 20 min. The overall results appeared that NATO with electrochemical ozone generation could be employed to treat palm oil mill wastewater with high efficiency due to •OH and O3.

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.

Lithium-ion batteries (LiBs) are found in all aspects of our lives - from small portable electronic devices through electric vehicles (EVs) to battery energy storage systems (BESS). LiBs are perceived as crucial to support the wide adoption of renewable energy sources as these do require BESS to manage the intermittency in their power supply for a reliable operation of the electricity grid. The application of LiBs in electric traction has initiated a revolution in the automotive industry that is motivated to decarbonise the transport sector and reduce local air pollution.This surge in demand for batteries will require a concomitant increase in production and, down the line, large numbers of LiBs reaching end-of-life (EoL). Hence, that will cause an ever-increasing battery waste that needs to be managed accordingly. However, many types of batteries currently do end up in landfills or are incinerated, primarily due to the lack of adequate standards; enforcement of regulatory controls and/or inefficient, or absence of, national battery collection and recycling schemes. As a result, human health and that of the environment could be placed at risk as a wide range of pollutants could be released like heavy metals or hydrofluoric acid (HF).This work presents the hazards that are resealed from abused and spent LiBs. The former incorporates nail penetration experiments carried out at various Stage of Charge (SoC). Initially, the thermal runaway was visible by the evolution of a thick, white vapour via the pyrolysis of the electrolyte. This vapour is comprised of H2, SO2, NO2, HF, HCl, CO, CO2, droplets of organic solvent and a large range of small chain alkanes and alkenes. For SOCs, >50%, this vapour inevitably ignites in less than 1 min. However, at low SOCs, ≤50%, the vapour may not ignite without sufficient air. Therefore, this phenomenon could lead to flash fire, fireballs developing, or in extreme cases, even a vapour cloud explosion in a confined space. Despite the explosion hazard, there is also the toxicity of the white vapour that must be faced by first responders wherever large LiBs are present in an enclosed space and one or more cells are in thermal runaway. That leads to concern for warehouses, battery manufacturing plants, electric vehicle assembly plants, road, rail and sea transportation of EVs/battery packs, hybrid electric ships and ferries using LiBs.The latter investigates the post-mortem release of contaminants from burnt LiBs. Depending on the disposal practice that may discharge various hazardous materials such as heavy metals, Volatile Organic Compounds or Polycyclic Aromatic Hydrocarbons etc. That may lead to a serious negative impact on the environment and human health.

Li-ion batteries (LiBs) in electric vehicles (EVs) finish their life with a significant amount of capacity left in them (about 80% of the nominal capacity), which provides a promising avenue for reusing the spent EV-batteries in less demanding second-life applications, such as grid-scale energy storage for peak shaving, EV charging, storage for intermittent energy sources (solar or wind power), backup storage for industries and property owners, and less demanding vehicle propulsion (ferries or forklifts) [1, 2]. However, reusing spent EV batteries in second-life applications is not as straightforward as taking a battery pack from an EV then installing it directly into a second-life application. One must consider the state-of-health (SoH) of the battery packs and hence the modules and cells to avoid any mismatch in terms of capacity, state-of-charge/depth-of-discharge (SoC/DoD). Even within the batteries suitable for reuse, cells must be sorted by similar remaining capacity and identical degradation state, or else the second-life system performance would suffer. The SoH needs careful assessment and ageing conditions evaluated to send heavily degraded batteries to recycling facilities. Whilst assessing the SoH is straightforward [3], identifying the ageing condition is complex, as ageing and degradation of LiBs over time are caused by various factors, including charging/discharging rate (C-rate), operating temperature, lifetime, SoC, and cycling [2]. Moreover, pack design, configuration, cooling methods as well as cell/module’s orientation in a pack can influence the battery degradation. In the present study, the effect of cell orientation on battery ageing and degradation has been investigated that can have an impact on the life of a battery in second-life applications. Eight large-size pouch batteries from two differently orientated modules from a dismantled first-generation Nissan Leaf retired battery pack have been analysed utilising infrared (IR) thermography and electrochemical impedance spectroscopy (EIS) techniques along with a brand-new second-generation Nissan Leaf battery which has almost the same geometry as batteries from the retired pack. Temperature derivative maps over the battery surface during discharging have been analysed, which show a direct correlation with the battery’s heat generation rates. Obtained results show that the thermal behaviour of brand-new batteries in orientations mimicking aged battery's orientation in the pack during EV life are very similar showing that the temperature derivative map’s hot spot is more towards the edge opposite to gravity vector (Figure 1 left). Also, EIS results (RCT+RSEI, charge transfer and solid electrolyte interphase layer resistances) show a wider range over SoCs for rotated-aged than flat-aged cells (Figure 1 right). It is worth noting that cells aged in flat orientation retained higher capacity compared to the cells aged in rotated orientation. These results show that different LiB orientations in EV batteries cause ageing non-uniformities over the battery surface, which would impact their second-life applications [4]. Non-uniform ageing is found to be more pronounced for the rotated module compared with the flat orientation inside the battery pack (Figure 1). Based on the present results, it is clear that avoiding different orientations in the battery pack can be a sustainable design for future EV battery back if reusing of spent EV batteries is envisaged. This work was part of the ReLiB project (https://relib.org.uk) and was supported by the Faraday Institution (https://www.faraday.ac.uk; grant numbers FIRG005 and FIRG027). References [1] ReLiB: Reuse and Recycling of Lithium-ion Batteries, accessed 12 December 2021, . [2] P.S. Attidekou, Z. Milojevic, M. Muhammad, M. Ahmeid, S. Lambert, P.K. Das, “Methodologies for large-size pouch lithium-ion batteries end-of-life gateway detection in the second-life application,” Journal of the Electrochemical Society, vol. 167, pp. 160534, 2020, DOI: 10.1149/1945-7111/abd1f1. [3] M. Muhammad, M. Ahmeid, P. Attidekou, Z. Milojevic, S. Lambert, P. Das, “Assessment of spent EV batteries for second-life application”, 2019 IEEE 4th International Future Energy Electronics Conference (IFEEC), IEEE, pp. 1-5, 2019, DOI: 10.1109/IFEEC47410.2019.9015015. [4] Z. Milojevic, P.S. Attidekou, M. Muhammad, M. Ahmeid, S. Lambert, P.K. Das, “Influence of orientation on ageing of large-size pouch lithium-ion batteries during electric vehicle life,” Journal of Power Sources, vol. 506, pp. 230242, 2021, DOI: 10.1016/j.jpowsour.2021.230242 Figure 1

In the electric vehicle (EV) battery packs, large-size lithium-ion pouch batteries (LiBs) are mostly used and to miniaturise the battery pack's volume, some manufacturers put the LiBs in different orientations. It is well established that temperature gradients over large-size LiBs surface cause ageing non-uniformities, but the influence of the LiBs orientation on the ageing has to date received little attention. Here, we present an analysis of orientation influence on the large-size pouch LiB's ageing on eight batteries from two differently orientated modules from the dismantled first-generation Nissan Leaf retired battery pack. The influence of orientation is also analysed for brand-new second-generation Nissan Leaf battery which has almost the same geometry as batteries from the retired pack. By utilising infrared (IR) thermography and electrochemical impedance spectroscopy (EIS) techniques, the influence of orientation on the LiBs ageing non-uniformity is detected. Whilst temperature maps analysis shows different LiBs' thermal behaviour depends on their orientation, EIS measurements show that ageing non-uniformity can be identified by analysing the solid-electrolyte-interphase and charge-transfer resistances. Presented results show that different LiBs orientation in EV battery packs should be avoided because it can cause ageing non-uniformities over the battery surface and their second-life applications should be applied with caution.

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.

Quality control in the production of automotive Li-ion cells is essential for both safety and economic reasons. At present, as part of the production process, it is common practice to store Li-ion cells for up to two weeks to analyze self-discharge performance and to subject sample cells to months of cycling to assess lifetime performance. This paper presents a new state-of-the-art nondestructive testing technique for automotive scale, Li-ion batteries. Importantly, the test can discriminate between viable and nonviable cells in less than one minute. This is significantly quicker than many industrially applied techniques. The proposed method, developed in partnership with three independent original equipment manufacturer automotive Li-ion cell manufacturers, uses empirical data gathered off-line for benchmarking cell response followed by a unique targeting process to reduce the test time to a level compatible with industrial manufacturing processes. The technique used is a targeted form of electrochemical impedance spectroscopy (EIS) using a commercially available potentiostat with EIS capability. The novel aspect of the research is the treatment of off-line empirical data, the construction of an empirical library database, and the development of a reliable and robust in-line test procedure. For reasons of commercial sensitivity, no knowledge of the underlying chemistry of the cells is available for use. This demonstrates the functionality of the proposed method across a range of different cell technologies and its applicability to multiple battery technologies.

Electric vehicle (EV) batteries typically retained around 70- 80% of their initial capacity at the end of their automotive life. The first batches EV batteries are hitting their retirement age and around 3 million used battery packs will be coming out from EV annually which represent around 108 GWh. Automotive companies and OEM have announced numerous projects and business models for second-life batteries, such as the stationary energy storage system (ESS) to extract additional services and revenue in post automotive life with cross-cutting benefits. The potential of second-life batteries lies in their state of health (SoH) or remaining useful life. To enable this market for second use batteries, it is necessary to demonstrate the capability of such batteries in real-world scenarios and validating the longevity of these batteries in this application is critical. This paper characterises three selected Nissan Leaf Cells/Modules disassemble from 24 KW Nissan Leaf pack that reach an end of life (EoL). The modules are tested individually to provide insight into the variation in degradation across a single battery pack and also establish the available energy at EoL via Hybrid pulse power characterization (HPPC). The result shows three data points of capacity and Ohmic resistance. Furthermore, the batteries achieved the power density of 700 W/Kg/300 W/Kg during discharge/regen in the working regions from 100% to 30% and /80% to 20% DOD respectively. Besides, the HPPC micro cycle discriminates between the strong and weak battery in 120 s.

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.

Electric vehicles (EV) typically have around 80% of their initial capacity at the end of the battery life. It is widely anticipated that these EV batteries will retain significant capacity remaining and potentially operate for additional years in their second life. Finding ways to repurpose the batteries in home, industrial and grid-scale energy storage system (ESS) is becoming more urgent. Establishing or verifying battery performance in comparison to these targets is a principal objective. Non-availability of onboard diagnostics data and accurate assessments of the automotive and second use battery degradation stand out in particular. This paper characterises the energy and power density of a cell using a hybrid pulse power characterisation (HPPC) test. Experimental results from five randomly selected cells from disassemble Nissan leaf pack that reach end of life (EoL) shows that all the cells satisfied the ESS performance targets of electric vehicle (EV) of 700 W/Kg, 300 W/Kg during discharge/regen respectively. The paper further proposes the used of HPPC micro cycle based on offline data for feature extraction to distinguish between power and energy density of the cell in 80 s, which is significantly quicker.

This paper reports thermal (burner) and mechanical (blunt trauma and nail penetration) abuse experiments on electric vehicle lithium ion modules comprising eight 56.3 Ah lithium nickel manganese cobalt (NMC) pouch cells. The aim of project part of which is described in this paper was to study the problem of thermal runaway in lithium ion batteries under different abuse conditions and at different SOC and to bridge the current gap in the literature between cell level studies and research at pack and system level. These experiments were part of an ongoing research programme leading up to studies at pack and system level. The responses of the cells to the various forms of abuse were monitored with optical and thermal cameras, thermocouples and by measuring cell voltage. Draeger gas sensors were also employed where possible. The nail penetration experiments were carried out at (nominally) 96.5%, 75% and 50% SOC, and at 96.5% SOC as a function of penetration location: the experiments strongly suggest that low SOC is as hazardous as high SOC, in contrast to a general perception in the literature, as the likely hazards are simply different and include the possibility of violent vapour cloud explosion. Thus, in all experiments, the first obvious indication of thermal runaway was the ejection of white vapour: if this ignited, the obvious hazard was that of fire. If, however, the vapour did not ignite, it posed an entirely different hazard in terms of high toxicity and the potential for a violent vapour cloud explosion: this is the first mention of such a phenomenon linked to lithium ion batteries in the academic literature. The experiments showed that cell voltage cannot be employed as a reliable warning of thermal runaway. Finally, the data obtained support a wholly novel theory, yet to be adopted across the community, in which thermal runaway can involve the direct solid-state electrochemical reaction between anode and cathode at temperatures ≥250 ˚C following venting of the electrolyte.

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.

A theoretical equivalent circuit model of two 40 Ah commercial batteries supplied by Saft was formulated to interpret electrochemical impedance spectra as a function of temperature at zero state-of-charge. The batteries were chosen to represent viable and non-viable products from the Saft production line. This paper is the first contribution from a project in Newcastle to develop a rapid, non-destructive analytical method for quality control on the battery production line. Using the model, it proved straightforward to discriminate between viable and non-viable batteries based on the temperature dependence of the electrochemical reaction kinetics at the electrodes, the average diffusion coefficients and the charge transfer resistances. Furthermore, as well as marked differences, for example, between the time constants, activation energies, polarisation resistances of the viable and non-viable batteries, the individual contributions of the anodes and cathodes in the batteries were de-convoluted and interpreted through the model framework.

Ordered mesoporous rutile and anatase TiO2 samples are prepared using mesoporous silica SBA-15 as template and freshly synthesized titanium nitrate and titanium chloride solutions as precursors. The rutile material formed from the nitrate solution is monocrystalline and contains minimal amounts of Si with a Si:Ti ratio of 0.031(4), whereas the anatase material formed from the chloride solution comprises nanocrystals and contains a higher content of Si with a Si:Ti ratio of 0.18(3). It is found that control of temperature and selection of Ti-containing precursor play important roles in determining the crystal phase and crystallinity. A possible formation mechanism of porous crystalline TiO2 is suggested. Characterization of these porous materials is performed by XRD, HRTEM, and nitrogen adsorption/desorption. SBA-15-templated mesoporous rutile TiO2 exhibits a higher Li ion insertion capability than KIT-6-templated TiO2 due to its larger surface area. Likewise mesoporous anatase TiO2:SiO2 composite has a better photoactivity than bulk TiO2 or TiO2-loaded SBA-15 for bleaching methylene blue.

Mesoporous monocrystalline rutile TiO2 has been fabricated at low temperature using mesoporous silicas SBA-15 and KIT-6 as hard templates. The key step of the synthetic process was introducing titanium nitrate complex into the template pores and allowing it to dry, dehydrate, decompose, and finally, form TiO2 crystals in the pores. It was found that the reaction temperature and concentration of HNO3 in the used precursor had great effects to the crystallization of TiO2. Removal of the silica templates after the TiO2 crystallization has been investigated. Crystallization of TiO2 in cage-containing mesoporous silicas, FDU-12 and SBA-16 was not successful, further confirming the previous speculation about strong interaction between the crystals and the wall of silica cages. The porous titanium oxide specimens were characterized by using various techniques, including XRD, HRTEM, and nitrogen adsorption/desorption. Proton conductivity and Li-ion insertion property of the samples were also examined. The highest...

The synthesis of La1+xBa2−xMn2O6 (0.2 ≤ x ≤ 0.4) under reducing conditions is reported. Neutron powder diffraction studies indicate an A-site ordered, oxygen deficient bilayer Ruddlesden–Popper structure. La3+ ions preferentially occupy oxygen vacant layers within the perovskite bilayers, leading to a structure analogous to the cuprate superconductor La1.85Ba0.15CaCu2O6+γ, with “MnO2” layers constructed from corner-linked square pyramidal MnO5 units. Magnetic measurements suggest that no long range magnetic order exists in this mixed Mn2+/Mn3+ system. Significantly, the low temperature oxidation of this phase leads to the synthesis of La1+xBa2−xMn2O6.95, which constitutes the first isolation of a complete barium analogue of La1+xSr2−xMn2O7, the important low field colossal magnetoresistive material. Neutron diffraction data confirm the retention of A-site order and a change in Jahn–Teller distortion. Low temperature neutron data and magnetic susceptibility suggest canted A-type antiferromagnetic order.