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Johnson Matthey Technol. Rev., 2020, 64, (3), 287
doi: 10.1595/205651320X15783059820413

Battery Materials Technology Trends and Market Drivers for Automotive Applications

Challenges for science and industry in electric vehicles growth

  • Sarah Ball, Joanna Clark, James Cookson*
  • Johnson Matthey, Blounts Court, Sonning Common, Reading, RG4 9NH, UK
  • *Email: james.cookson@matthey.com

Article Synopsis

With the electric vehicle (EV) market set to grow rapidly over the coming years, the industry faces a challenging ramp-up of volume and material performance demands. From the current trend towards high-energy high-nickel cathode materials, driven in-part by consumer range anxiety, to the emergence of solid-state and beyond lithium-ion technologies, herein we review the changing requirements for active materials in automotive Li-ion battery (LIB) applications, and how science and industry are set to respond.

Introduction

Outdoor air pollution is linked to an estimated 4.2 million deaths each year worldwide (1). Tailpipe emissions from conventional internal combustion engine (ICE) vehicles are a major contributor to urban air pollution, and as such have been subject to ever tighter legislation for decades, requiring increasingly innovative improvements and catalytic emissions controls. We have now reached the point where a move away from the ICE is required to continue air quality improvements, with several countries going so far as banning new purely ICE vehicles in the coming years. This is where EVs will play their part – both pure EV and hybrid systems powered by LIB technologies, as well as fuel cell technologies, are set to see increased uptake and demand as we strive for cleaner air. In this article, we will add to the automotive-focused literature (2–4) and review what technologies are required to drive the uptake of pure EVs, and what the industry is doing now to respond to consumer requirements as this market rapidly grows.

There are several characteristic battery parameters that it is important to consider and contrast with consumer behaviours and expectations for automotive applications: perhaps most significant, the energy or capacity of the cell equates to the ‘miles in your tank’, and is an area where EVs have lagged behind the ICE in previous years. This is evolving, with the most successful EVs on the market now having an average range of 350 km (5). Range anxiety, equating to energy density, is a major theme for the battery materials industry, with contributions from and innovations required in three areas: the cathode, anode and electrolyte. Cost is also an important factor; as well as the material costs for the active components, analysis has shown that the electrode thickness within the cell is a major contributor to automotive cell costs (6) – materials with increased volumetric energy density are therefore additionally attractive from this perspective. There is also the practical cost benefit afforded by developing systems that can operate at higher voltage cut-offs (7), owing to the usable advantages, towards which multiple cell components can be developed and optimised. Herein, we review one topic of significant industry focus from each area: high-Ni cathode materials, with lithium nickel manganese cobalt oxide (NMC) 811 and beyond being commercialised within the next three years; high energy silicon anode technologies, expected to be at commercial scale in the next three to five years; and solid-state electrolytes, with significant progress expected from the next five years and beyond.

High Energy Cathode Advancements

Whilst the cathode active material technology landscape remains diverse, with no one material that will meet all EV requirements, the general trend for passenger EVs is using high-Ni NMC, and lithium nickel cobalt aluminium oxide (NCA) materials. The layered Li Ni oxide (LNO), has been studied for the past 25 years, ever since the commercial application of the isostructural Li Co oxide (LCO) by Sony, Japan, in 1991; the relative low cost of Ni compared to Co was an initial driver for this work – and continues to be a factor today (8–12). Until relatively recently, automotive industry uptake was focused on lower Ni NMC variants, such as LiNi1/3Mn1/3Co1/3O2 (NMC 111), and lower energy chemistries such as Li Mn oxide (LMO), and Li iron phosphate (LFP). Tesla, USA, bucked the trend; as an early adopter of higher‐Ni NCA materials, it was ahead in the EV mileage stakes. Now, driven by consumer demand for more range, high-Ni is in vogue – the key for research and industry alike is to innovate-out the technical problems associated with LNO regarding its stability.

LNO tends towards non-stoichiometry, owing to the relative instability of Ni3+ compared to Ni2+, and the similar ionic radii of Ni2+ (0.69 Å) and Li+ (0.73 Å) (12, 13). It has been shown that synthesis conditions are key to prevent the formation of Ni2+ anti-site defects, with near-stoichiometric LNO requiring control of calcination temperature, atmosphere and Li content (12, 14). LNO is also known to undergo several phase transformations on electrochemical cycling; whilst a capacity of over 200 mAh g–1 can be achieved, these transformations lead to significant capacity fade over the first cycles (15). Early research showed the benefits of incorporating relatively small amounts of other metals, most notably Co, Al and Mn, into the structure to impart stability and significantly improve capacity retention. Owing to the isostructural nature of its end members, all compositions in the series LiNi1–x Cox O2 (x = 0–1) can be formed; Co3+ imparts stability by hindering the formation of Ni2+ anti-site defects (16). Conversely, doping Mn into the LNO structure has been shown to detrimentally effect the reversible capacity but to impart thermal stability benefits – a key property for battery safety (17, 18). The beneficial effect of Al substitution at low levels is two-fold: an improvement in capacity retention by minimising detrimental phase transformations and an increase in thermal stability (18, 19). There is, however, a limitation to the amount of Al that can be usefully incorporated into the structure; the addition of high-levels of an electrochemically inactive dopant will result in a reduction in capacity, and Al3+ has been shown to segregate and create localised defects within the lattice, due to the different ionicity of Al–O and Ni–O bonds (20).

This combined work has ultimately led to continued focus on the multiple metal dopant strategies found in NCA and NMC, where greater benefits are observed than in single dopant systems. Whilst not as catastrophic as those in LNO, NCA and high-Ni NMC materials (such as NMC 811) undergo significant structural changes on cycling, which their lower Ni counterparts (for example NMC 622, NMC 111) do not (Figure 1): at high states of charge, a transformation from the second hexagonal phase (H2) to the third hexagonal phase (H3) occurs in high-Ni materials that is associated with c lattice contraction and capacity fade (21–23). The addition of dopants to the bulk structure of LNO such as cobalt, manganese, aluminium, magnesium, titanium and combinations thereof has been shown to influence stability by affecting the volume change on cycling associated with the H2/H3 phase transformation (24–26).

Fig. 1.

Differential capacity vs. cell voltage of NMC-graphite cells recorded at a 0.1 C-rate (3rd cycle). The peaks are assigned to their corresponding phase transitions with H1, H2 and H3 representing the three hexagonal phases and M the monoclinic one. C6 → LiCx indicates the lithiation of graphite (21) Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 (CC BY-NC-ND)

Coating strategies have been employed to high‐Ni NCA and NMC systems, providing benefits in two key areas: handling and performance. The handling and processability of high-Ni materials is a well-known challenge, with surface reactivity towards the ambient resulting in the formation of Li hydroxide and Li carbonate impurities, and the resultant propensity of electrode slurries to gel: this creates obvious challenges before materials have even reached the cell (27–29). Once in the cell, these surface impurities contribute to resistance growth and side reactions resulting in gassing (30, 31). Moreover, the high-Ni surface itself is known to undergo phase changes upon cycling, with the formation of the rock salt phase Ni oxide also contributing to instability and capacity fade (32, 33). In its simplest sense, the application of an inactive coating such as Al oxide passivates the surface with respect to these undesirable side reactions, creating more benign materials that are easier to handle; but only so much of this type of coating can be applied before either significant capacity loss or resistance gains are observed (34). As such, the move toward active coatings, where the removal of an inherent risk of capacity loss does not limit the amount or depth of coating that can be applied, is very attractive. A notable example in this area is the extensive work by the Sun group, who have developed several generations of active coatings and complex morphologies for high-Ni materials (Figure 2): starting with a core@shell strategy, a low-Ni NMC was applied to the surface of a high-Ni NMC, creating a system that combined a high-energy core with a high-stability surface and building a system that was electrochemically active throughout (35). The drawback of this system was the observation that the shell layer broke away from the core on cycling, due to the mismatched volume changes within the core and shell NMC layers. To counteract this, the group developed a gradient coating strategy, whereby a lattice expansion or contraction mismatch was avoided by creating a continuous region of gradual compositional change, thus removing a core@shell interface (38). The Sun group further extended this work to look at deeper and multi-component gradients and their potential benefits (36, 37, 39). Such gradient systems can be viewed as a sophisticated hybrid between bulk doping and surface coating strategies, helping to mitigate the trade-offs associated with each strategy alone.

Fig. 2.

Development of core@shell and gradient NMC materials: (a) scanning electron microscopy image of Ni-rich core and Mn-rich shell, showing interfacial cracking after cycling, reprinted with permission from (35), Copyright 2005 American Chemical Society; (b) schematic diagram of full gradient material, reprinted with permission from (36), copyright 2012 Springer Nature; (c) electron probe microanalysis (EPMA) line scan of the integrated atomic ratio of transition metals as a function of the distance from the particle centre to the surface for the precursor; and (d) EPMA line scan of the integrated atomic ratio of transition metals as a function of the distance from the particle centre to the surface for the lithiated gradient material, reprinted with permission from (37), copyright 2015 John Wiley and Sons

These gradient systems demonstrate the importance of considering morphology and process alongside composition in materials engineering. Another area of interest is the mitigation of microcrack formation through the control of primary particle shape, size and interfaces; fewer cracks means a more stable cathode electrolyte interface (CEI) layer, alleviating resistance growth and gas-generating side reactions (33, 40, 41). Most recently, this has led to particular interest in single crystalline morphologies, which promise greater long-term cycling stability compared to their polycrystalline counterparts by minimising the number of interfaces where microcracks can occur. The majority of published research in this area has focused on lower-Ni NMCs (i.e. NMC 622 or less), where reduction in gassing has been observed compared to polycrystalline counterparts, albeit at the cost of rate capability (42, 43). This lower Ni focus is in part due to the challenging nature of high Ni synthesis at the typically elevated temperatures required to form single crystalline materials compared to those used to generate polycrystalline materials. There are examples demonstrating similar advantages for a single crystalline morphology with up to 80% Ni content and efforts are clearly growing in this area: single crystalline NMC 811 has been shown to exhibit less gassing than its polycrystalline counterpart during high temperature storage (30). Zhu et al. undertook a broad study looking at NMCs from NMC 111 to NMC 811 prepared by multiple approaches and demonstrated the need to tune synthesis conditions to Ni content (44).

The engineering opportunities to overcome the challenges presented by high Ni materials continue to grow. As the automotive industry strives for higher energy, the drive to increase the Ni content of NCA and NMC type materials is clear – the common theme across the industry is to move from NMC 622 to NMC 811 and toward 90% Ni content to meet energy requirements, but also to reduce the Co content required, due to sourcing and cost challenges. Ultimately, a combination of the strategies reviewed above are required to develop and commercialise materials with a Ni content of 80% and above to meet the energy and stability requirements of the automotive industry.

High Energy Anode Advancements

Aligned with the drive toward higher energy cathode materials, there is a requirement to enhance and optimise LIB anode materials toward greater energy density, improved cycle life, lower cost per kilowatt hour and improved gravimetric and volumetric densities (3, 46). In particular, the use of higher energy cathode materials allows increased ampere hour per geometric area and volume of active cathode which is important to retain realistic active material loadings and thicknesses and achieve battery EV (BEV) cell and pack targets. A commensurate improvement in storable energy per area and volume of anode electrode is therefore also required. Cell manufacturers and original equipment manufacturers (OEMs) are increasingly moving beyond todays natural and synthetic graphite materials (or combinations of these) toward blending graphite with a higher energy density Si or Si oxide component to enhance cell level energy gravimetric and volumetric density (47). Table I illustrates examples of such Si containing materials (48).

Table I

Comparison of Anode Materialsa

Anode material C Si SiOx
Volume change % during lithiation 12 280 160
Lithiated phase LiC6 Li15Si4 Lix Si, Li2O, Li4SiO4
Initial theoretical specific capacity, mAh g–1 372 3579 3172
Typical initial coulombic efficiency, % 90–95 77.5–84 65–95

aReproduced from Chen et al. and references therein (48)

The high natural abundance of Si and low operating voltage (0.2 V discharging potential compared to Li/Li+) single out Si as a highly promising anode material for LIBs (49). However, Si containing materials as battery anodes exhibit a number of challenges, with the greatest of these being significant volume expansion during the lithiation process (see Table I). Particle cracking or fragmentation, loss of electrical contact, ongoing parasitic reactions between electrolyte and ‘fresh’ surfaces, cell swelling and gassing all contribute to cycle life issues (see Figure 3 and Figure 4) (46). Various approaches can be deployed to address the volume change issue for pure Si anodes, including nano-engineering of the Si electrode structure (nanowires and nanoparticles, formation of secondary agglomerates) along with advanced binder combinations to create a flexible electrode structure (46, 50, 51). The addition of carbon dioxide into pouch cells has also been trialled to limit parasitic reactions (52). Formation of nanocomposites of Si–C via mechanical or chemical deposition processes, addition of other alloying components or the choice of a SiOx material (where first cycle lithiation allows an irreversible reaction creating stabilising LiOx and Li silicate components within the structure) can all bring improvements (50, 53). Incorporation of conductive carbon also addresses the challenge posed by the intrinsic low conductivity of Si containing materials (54).

Fig. 3.

Schematic of the changes occurring at the surface during electrochemical cycling of bulk Si, illustrating how large volumetric changes result in cracking, fragmentation and loss of electrical contact to active material, reprinted with permission from (46), copyright 2017 American Chemical Society

Fig. 4.

Illustration of the evolution of Si particle solid electrolyte interface (SEI) with repeated cycles, reprinted with permission from (46), copyright 2017 American Chemical Society

A strategy of blending Si containing materials with existing graphite types is already in progress to achieve moderate capacity increase and lessen volume change, as illustrated by cell level calculations for this approach (for example Si:C 1:3 with capacity of 1100 mAh g–1 by Andre et al.) (3, 47). Table I illustrates an additional challenge present in Si containing anodes in the form of lower first cycle efficiency (FCE) vs. graphite, related to reactions consuming Li between the electrolyte and anode, the formation of the SEI and associated reduction in useful Li inventory in the working cell, reducing effective watt hour per kilogram. Pre-lithiation approaches, where sacrificial Li containing materials are added to the Si anode during electrode fabrication or strategies such as electrochemical pre-lithiation of formed electrodes ahead of cell assembly are possible (55, 56) along with chemical pretreatments ‘artificial SEI formation’ (57, 58). However, these all represent additional steps and cost in a cell manufacturing process, also pre-lithiated materials and electrodes and Si nanoparticles require careful handling due to the reactivity of the materials with moisture and air (48).

Careful optimisation of the liquid electrolyte additives is also crucial to achieve prolonged cycle life and good FCE, with fluorinated additives, especially fluoroethylene carbonate (FEC), showing benefit (59). The discharge and charge voltage profile of Si containing anodes is slightly different to graphite-only examples, leading to reduced chance of Li plating during charging in Si anodes, but typically slightly lower discharge voltage with graphite, thus adjustments to cell balancing and understanding of the operational state of charge window in the usable voltage range are important for full cell (60).

Assessment of the sustainability of changing to Si containing anode components and advanced higher energy cell chemistries is also vital as electrification of the power train advances worldwide (61).

Higher Energy Through Solid-State Electrolytes

A further driver to increase the energy density of cells is to replace existing anode materials with metallic Li. Li metal was used as the first anode material in rechargeable Li-ion cells due to its very high energy density (3860 mAh g–1) and low electrochemical potential (–3.040 V vs. the standard hydrogen electrode). However, numerous challenges prevented its widespread adoption, including low cycle life predominating from issues such as the formation of dendrites and unstable solid-electrolyte interfaces. Recently, there has been increasing investigations into using solid-state electrolytes to mitigate the challenges of using metal anodes, whilst maintaining their advantages.

In addition to potentially enabling the use of Li metal anodes, the evolution to solid state batteries has other advantages to conventional Li-ion cells (62). The primary reason is the displacement of the highly flammable cocktail of organic electrolytes that is used currently. This both reduces the risk of unwanted thermal events in the instance of cell misuse or damage, but it also results in a simpler packaging, further increasing the energy density (63) (Figure 5). In addition, solid state materials could offer increased electrochemical stability windows in comparison to existing organic electrolytes; potentially enabling alternative materials, such as higher voltage cathode materials, to be deployed.

Fig. 5.

What is the advantage in energy density of a cell? Reprinted with permission from (64), copyright 2018 Springer Nature

Polymer Gels

The use of polymers as electrolytes in batteries was first pioneered in the 1970s (64, 66). This enables cells with high degrees of safety to be manufactured in various form factors. Polymer-based systems such as polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), polyacrylonitrile and polymethyl methacrylate (PMMA) based electrodes have all been widely studied as polymer electrolytes (67). PEO-based polymer electrolytes have been studied the most due to their advantageous properties including lower cost, ability to solvate a wide variety of ions, relatively high chemical stability and the use of their moderate mechanical strength (~106 Pa) to supress the growth of dendrites (68, 69). However, the low conductivity (~10–7 S cm–1) of the electrolyte systems, due to the crystallinity of the polymer chains, has been a limitation (70). Overall, the general uptake of polymer gel cells has been restricted by their lower energy densities and poor electrochemical stability compared to liquid electrolytes.

All Solid-State Batteries

More recently, researchers have explored a range of solid inorganic materials, which allow ionic mobility through the solid. Numerous classes of these are currently being explored, all possessing different advantages and disadvantages (63, 71, 72). A summary of these are highlighted in Table II.

Table II

Selected Parameters for Key Classes of Solid-State Electrolytes

Type Example composition Ionic conductivity at room temperature (RT), S cm–1 Electrochemical stability to Li
Sulfide Li10GeP2S12 (73) 1 × 10–2 Stable
Garnet Li7La3Zr2O12 (74) 3 × 10–4 Stable
Sodium superionic conductor (NASICON) Li1.3Al0.3Ti1.7(PO4)3 (75) 7 × 10–4 Unstable
Perovskite Li0.34La0.51TiO2.94 (76) 2 × 10–5 Unstable
Lithium phosphorous oxynitride (LiPON) LiPON (77) 6 × 10–6 Stable
Anti-Perovskite Li3OCl (78, 79) 9 × 10–4 Stable
Argyrodite Li6PS5Cl (80) 1 × 10–3 Stable

Researchers have looked to examine inorganic electrolyte materials with high ionic conductivities, such as Li10GeP2S12, which exhibits high conductivity at RT (73). However, sulfide-based solid electrolytes are generally expensive, more challenging to synthesise and are sensitive to moisture, potentially releasing toxic gases. This brings challenges in their handling and subsequent fabrication.

Although most solid electrolytes have been shown to react with Li metal, garnet materials (such as Li7La3Zr2O12 (LLZO)), have shown the greatest stability (74, 75). In addition, they have relatively low costs and a wide electrochemical window (~6 V vs. Li metal) potentially enabling the use of higher voltage cathode materials; and are therefore attracting increasing investigations (74). The cubic phase of LLZO is found to offer greater ionic conductivity than the tetragonal phase. A typical strategy to promote this is to dope elements such as Al, tantalum and gallium into the structure thus stabilising the highly conductive cubic phase at RT (76).

Despite these advantages, a challenge in using LLZO remains its instability in the ambient atmosphere, due to CO2 and moisture (77). This results in increased complexity upon subsequent material handling and processing. Further challenges include poor interfacial compatibility of LLZO with electrodes. To overcome this, methods to increase the wettability of the electrolyte have been explored, such as the atomic layer deposition of Al2O3 to reduce interfacial resistance by the formation of a desirable Li-Al-O layer (73); or alloying Li with other elements (such as Si, Al, Ge) to increase compatibility (72).

In addition to the preparation of materials capable of high levels of Li-ion conductivity, it is vital that these materials can be manufactured at an industrial scale at a reasonable cost. While there has been considerable interest in the use of oxides for an all solid electrolyte, their brittleness and fragility impose new challenges for mass production (78, 80). As a result the scale up of such activities is being explored using a variety of different processing technologies (Figure 6). Mature slurry-based technologies have been shown to provide dense layers using high throughput techniques. However, subsequent high temperature sintering inhibits the co-firing of solid electrolytes and cathode particles.

Fig. 6.

Technology readiness of current solid-state electrolyte processing options: (a) technical feasibility – solid electrolyte fabrication; (b) technical feasibility – cathode composite fabrication; and (c) technology readiness – solid electrolyte fabrication, reprinted with permission from (78), copyright 2019 Royal Society of Chemistry

When using Li metal as an anode material it is vitally important to prepare dense electrolyte layers in the absences of holes. It has been suggested that a critical relative density of >93% are required to eliminate the formation of dendrites in LLZO electrolytes (79); with short circuits believed to propagate through voids and grain boundaries (81). To obtain highly sintered garnet-based solid electrolytes by conventional sintering techniques, generally high temperatures (>1200°C) and long sintering times (>30 h) are required. Such conditions can result in the decomposition of the solid electrolytes and loss of Li from the structure.

To overcome these challenges, alternative processes such as hot pressing, field-assisted sintering and spark plasma synthesis have been investigated to fabricate the optimal dense ceramic layer (82–85). To that end further evaluation of deposition and sintering technologies will be required to provide an economically viable solution.

Beyond Lithium-Ion

There are also multiple technologies (such as Li‐sulfur and Li-air chemistry) that have the potential to deliver significant advances in performance, such as increased energy density (86). For example, Li-S chemistry benefits from the low cost and high abundance of S and an energy density significantly higher than current Li-ion cells (~2500 Wh kg–1) (87, 88). However, these technologies currently suffer from technical challenges that limit their uptake. To fully maximise the benefit of these technologies, it is necessary to overcome the challenges of working with a Li metal anode. The use of solid-state electrolytes is a recent area where people have been exploring with the aim of enabling the technology via anode protection.

Summary

The demand for cleaner air is accelerating and this is giving rise to increased electrification in the automotive drivetrain. There is also a growing acceptance of vehicles with varying degrees of electrification, and this trend looks set to continue. Current concerns for increased energy density to counter consumer’s ‘range anxiety’ are leading to material developments to meet this. In particular, the careful design and manufacturing of cathode materials with high amounts of Ni and anode materials with increasing Si content are steadily improving these key parameters. Furthermore, significant exploration into next generation technologies, such as solid-state electrolytes, opens the possibility of redesigning the cell. While options to the type of material used and their processing remain; the replacement of conventional liquid electrolytes promises to deliver further improvements in energy density as well as other benefits, such as safety performance. These three examples highlight the major trends being investigated and introduced into automotive cells to meet the demands of society.

References

  1. 1.
    ‘Air Pollution’, World Health Organisation, Geneva, Switzerland: https://www.who.int/airpollution/en/ (Accessed on 20th April 2020)
  2. 2.
    D. Andre, H. Hain, P. Lamp, F. Maglia and B. Stiaszny, J. Mater. Chem. A, 2017, 5, (33), 17174 LINK https://doi.org/10.1039/c7ta03108d
  3. 3.
    D. Andre, S.-J. Kim, P. Lamp, S. F. Lux, F. Maglia, O. Paschos and B. Stiaszny, J. Mater. Chem. A, 2015, 3, (13), 6709 LINK https://doi.org/10.1039/c5ta00361j
  4. 4.
    S.-T. Myung, F. Maglia, K.-J. Park, C. S. Yoon, P. Lamp, S.-J. Kim and Y.-K. Sun, ACS Energy Lett., 2017, 2, (1), 196 LINK https://doi.org/10.1021/acsenergylett.6b00594
  5. 5.
    P. Harrop, R. Collins, L. Gear, N. Jiao, D. Wyatt and J. Edmondson, “Electric Vehicles 2020-2030: Markets, Technology, Manufacturers, Opportunities. Land, Water, Air: Unique Detail”, IDTechEx, Cambridge, UK, 2019 LINK https://www.idtechex.com/en/research-report/electric-vehicles-2020-2030/670
  6. 6.
    G. Patry, A. Romagny, S. Martinet and D. Froelich, Energy Sci. Eng., 2015, 3, (1), 71 LINK https://doi.org/10.1002/ese3.47
  7. 7.
    S. Ahmed, S. E. Trask, D. W. Dees, P. A. Nelson, W. Lu, A. R. Dunlop, B. J. Polzin and A. N. Jansen, J. Power Sources, 2018, 403, 56 LINK https://doi.org/10.1016/j.jpowsour.2018.09.037
  8. 8.
    M. Broussely, F. Perton, P. Biensan, J. M. Bodet, J. Labat, A. Lecerf, C. Delmas, A. Rougier and J. P. Pérès, J. Power Sources, 1995, 54, (1), 109 LINK https://doi.org/10.1016/0378-7753(94)02049-9
  9. 9.
    J. R. Dahn, U. von Sacken and C. A. Michal, Solid State Ionics, 1990, 44, (1–2), 87 LINK https://doi.org/10.1016/0167-2738(90)90049-w
  10. 10.
    J. R. Dahn, U. von Sacken, M. W. Juzkow and H. Al-Janaby, J. Electrochem. Soc., 1991, 138, (8), 2207 LINK https://doi.org/10.1149/1.2085950
  11. 11.
    T. Ohzuku, H. Komori, M. Nagayama, K. Sawai, and T. Hirai, Chem. Express 1991, 6, (3), 161
  12. 12.
    T. Ohzuku, A. Ueda and M. Nagayama, J. Electrochem. Soc., 1993, 140, (7), 1862 LINK https://doi.org/10.1149/1.2220730
  13. 13.
    L. Pauling, “The Nature of the Chemical Bond and the Structure of Molecules and Crystals: An Introduction to Modern Structural Chemistry”, 3rd Edn., Cornell University Press, New York, USA, 1960
  14. 14.
    I. Saadoune, M. Dahbi, M. Wikberg, T. Gustafsson, P. Svedlindh and K. Edström, Solid State Ionics, 2008, 178, (31–32), 1668 LINK https://doi.org/10.1016/j.ssi.2007.10.019
  15. 15.
    H. Arai, S. Okada, Y. Sakurai and J. Yamaki, Solid State Ionics, 1997, 95, (3–4), 275 LINK https://doi.org/10.1016/s0167-2738(96)00598-x
  16. 16.
    C. Delmas, M. Ménétrier, L. Croguennec, I. Saadoune, A. Rougier, C. Pouillerie, G. Prado, M. Grüne and L. Fournès, Electrochim. Acta, 1999, 45, (1–2), 243 LINK https://doi.org/10.1016/s0013-4686(99)00208-x
  17. 17.
    M. Guilmard, L. Croguennec and C. Delmas, J. Electrochem. Soc., 2003, 150, (10), A1287 LINK https://doi.org/10.1149/1.1601227
  18. 18.
    M. Guilmard, L. Croguennec, D. Denux and C. Delmas, Chem. Mater., 2003, 15, (23), 4476 LINK https://doi.org/10.1021/cm030059f
  19. 19.
    S. H. Park, K. S. Park, Y. K. Sun, K. S. Nahm, Y. S. Lee and M. Yoshio, Electrochim. Acta, 2001, 46, (8), 1215 LINK https://doi.org/10.1016/s0013-4686(00)00710-6
  20. 20.
    L. Croguennec, Y. Shao-Horn, A. Gloter, C. Colliex, M. Guilmard, F. Fauth and C. Delmas, Chem. Mater., 2009, 21, (6), 1051 LINK https://doi.org/10.1021/cm802954g
  21. 21.
    R. Jung, M. Metzger, F. Maglia, C. Stinner and H. A. Gasteiger, J. Electrochem. Soc., 2017, 164, (7), A 1361 LINK https://doi.org/10.1149/2.0021707jes
  22. 22.
    C. S. Yoon, D.-W. Jun, S.-T. Myung and Y.-K. Sun, ACS Energy Lett., 2017, 2, (5), 1150 LINK https://doi.org/10.1021/acsenergylett.7b00304
  23. 23.
    W.-S. Yoon, K. Y. Chung, J. McBreen and X.-Q. Yang, Electrochem. Commun., 2006, 8, (8), 1257 LINK https://doi.org/10.1016/j.elecom.2006.06.005
  24. 24.
    H. Li, P. Zhou, F. Liu, H. Li, F. Cheng and J. Chen, Chem. Sci., 2019, 10, (5), 1374 LINK https://doi.org/10.1039/c8sc03385d
  25. 25.
    F. Wu, N. Liu, L. Chen, Y. Su, G. Tan, L. Bao, Q. Zhang, Y. Lua, J. Wang, S. Chen, and J. Tan, Nano Energy, 2019, 59, 50 LINK https://doi.org/10.1016/j.nanoen.2019.02.027
  26. 26.
    C. S. Yoon, H.-H. Ryu, G.-T. Park, J.-H. Kim, K.-H. Kim and Y.-K. Sun, J. Mater. Chem. A, 2018, 6, (9), 4126 LINK https://doi.org/10.1039/c7ta11346c
  27. 27.
    D. Aurbach, A. Zaban, A. Schechter, Y. Ein-Eli, E. Zinigrad and B. Markovsky, J. Electrochem. Soc., 1995, 142, (9), 2873 LINK https://doi.org/10.1149/1.2048658
  28. 28.
    D.-H. Cho, C.-H. Jo, W. Cho, Y.-J. Kim, H. Yashiro, Y.-K. Sun and S.-T. Myung, J. Electrochem. Soc., 2014, 161, (6), A 920 LINK https://doi.org/10.1149/2.042406jes
  29. 29.
    K. Tasaki, A. Goldberg, J.-J. Lian, M. Walker, A. Timmons and S. J. Harris, J. Electrochem. Soc., 2009, 156, (12), A1019 LINK https://doi.org/10.1149/1.3239850
  30. 30.
    H. Kobayashi, M. Shikano, S. Koike, H. Sakaebe and K. Tatsumi, J. Power Sources, 2007, 174, (2), 380 LINK https://doi.org/10.1016/j.jpowsour.2007.06.134
  31. 31.
    Y. S. Jung, P. Lu, A. S. Cavanagh, C. Ban, G.-H. Kim, S.-H. Lee, S. M. George, S. J. Harris and A. C. Dillon, Adv. Energy Mater., 2013, 3, (2), 213 LINK https://doi.org/10.1002/aenm.201200370
  32. 32.
    D. P. Abraham, R. D. Twesten, M. Balasubramanian, I. Petrov, J. McBreen and K. Amine, Electrochem. Commun., 2002, 4, (8), 620 LINK https://doi.org/10.1016/s1388-2481(02)00388-0
  33. 33.
    Y. Cho, P. Oh and J. Cho, Nano Lett., 2013, 13, (3), 1145 LINK https://doi.org/10.1021/nl304558t
  34. 34.
    S.-T. Myung, K. Izumi, S. Komaba, Y.-K. Sun, H. Yashiro and N. Kumagai, Chem. Mater., 2005, 17, (14), 3695 LINK https://doi.org/10.1021/cm050566s
  35. 35.
    Y.-K. Sun, S.-T. Myung, M.-H. Kim, J. Prakash and K. Amine, J. Am. Chem. Soc., 2005, 127, (38), 13411 LINK https://doi.org/10.1021/ja053675g
  36. 36.
    Y.-K. Sun, Z. Chen, H.-J. Noh, D.-J. Lee, H.-G. Jung, Y. Ren, S. Wang, C. S. Yoon, S.-T. Myung and K. Amine, Nature Mater., 2012, 11, (11), 942 LINK https://doi.org/10.1038/nmat3435
  37. 37.
    B.-B. Lim, S.-J. Yoon, K.-J. Park, C. S. Yoon, S.-J. Kim, J. J. Lee and Y.-K. Sun, Adv. Funct. Mater., 2015, 25, (29), 4673 LINK https://doi.org/10.1002/adfm.201501430
  38. 38.
    Y.-K. Sun, B.-R. Lee, H.-J. Noh, H. Wu, S.-T. Myung and K. Amine, J. Mater. Chem., 2011, 21, (27), 10108 LINK https://doi.org/10.1039/c0jm04242k
  39. 39.
    J.-W. Ju, E.-J. Lee, C. S. Yoon, S.-T. Myung and Y.-K. Sun, J. Phys. Chem. C, 2014, 118, (1), 175 LINK https://doi.org/10.1021/jp4097887
  40. 40.
    M.-J. Lee, M. Noh, M.-H. Park, M. Jo, H. Kim, H. Nam and J. Cho, J. Mater. Chem. A, 2015, 3, (25), 13453 LINK https://doi.org/10.1039/c5ta01571e
  41. 41.
    Y. Cho, S. Lee, Y. Lee, T. Hong and J. Cho, Adv. Energy Mater., 2011, 1, (5), 821 LINK https://doi.org/10.1002/aenm.201100239
  42. 42.
    H. Li, J. Li, X. Ma and J. R. Dahn, J. Electrochem. Soc., 2018, 165, (5), A 1038 LINK https://doi.org/10.1149/2.0951805jes
  43. 43.
    J. Li, A. R. Cameron, H. Li, S. Glazier, D. Xiong, M. Chatzidakis, J. Allen, G. A. Botton and J. R. Dahn, J. Electrochem. Soc., 2017, 164, (7), A 1534 LINK https://doi.org/10.1149/2.0991707jes
  44. 44.
    J. Zhu and G. Chen, J. Mater. Chem. A, 2019, 7, (10), 5463 LINK https://doi.org/10.1039/c8ta10329a
  45. 45.
    ‘Presentation of Results for the Year Ended 31st March 2019’, Johnson Matthey, London, UK, 30th May, 2019 LINK https://matthey.com/-/media/files/investors/presentation-fy-1819-results.pdf?la=en&hash=5E34C55B76F463BFD9C67BB81C1071FCE29EC3F5
  46. 46.
    A. F. Gonzalez, N.-H. Yang and R.-S. Liu, J. Phys. Chem. C, 2017, 121, (50), 27775 LINK https://doi.org/10.1021/acs.jpcc.7b07793
  47. 47.
    K. Fehrenbacher, ‘Why Tesla’s New Battery Pack is Important’, Fortune, New York, USA, 24th August, 2016 LINK http://fortune.com/2016/08/24/tesla-100kWh-battery-pack
  48. 48.
    T. Chen, J. Wu, Q. Zhang and X. Su, J. Power Sources, 2017, 363, 126 LINK https://doi.org/10.1016/j.jpowsour.2017.07.073
  49. 49.
    X. Su, Q. Wu, J. Li, X. Xiao, A. Lott, W. Lu, B. W. Sheldon and J. Wu, Adv. Energy Mater., 2014, 4, (1), 1300882 LINK https://doi.org/10.1002/aenm.201300882
  50. 50.
    J. K. Lee, C. Oh, N. Kim, J.-Y. Hwang and Y.-K. Sun, J. Mater. Chem. A, 2016, 4, (15), 5366 LINK https://doi.org/10.1039/c6ta00265j
  51. 51.
    T. M. Higgins, S.-H. Park, P. J. King, C. Zhang, N. McEvoy, N. C. Berner, D. Daly, A. Shmeliov, U. Khan, G. Duesberg, V. Nicolosi and J. N. Coleman, ACS Nano, 2016, 10, (3), 3702 LINK https://doi.org/10.1021/acsnano.6b00218
  52. 52.
    L. J. Krause, V. L. Chevrier, L. D. Jensen and T. Brandt, J. Electrochem. Soc., 2017, 164, (12), A 2527 LINK https://doi.org/10.1149/2.1121712jes
  53. 53.
    W. Qi, J. G. Shapter, Q. Wu, T. Yin, G. Gao and D. Cui, J. Mater. Chem. A, 2017, 5, (37), 19521 LINK https://doi.org/10.1039/c7ta05283a
  54. 54.
    M. Ashuri, Q. He and L. L. Shaw, Nanoscale, 2016, 8, (1), 74 LINK https://doi.org/10.1039/c5nr05116a
  55. 55.
    C. R. Jarvis, M. J. Lain, Y. Gao and M. Yakovleva, J. Power Sources, 2005, 146, (1–2), 331 LINK https://doi.org/10.1016/j.jpowsour.2005.03.023
  56. 56.
    X. Yang, Z. Wen, X. Xu, B. Lin and S. Huang, J. Power Sources, 2007, 164, (2), 880 LINK https://doi.org/10.1016/j.jpowsour.2006.11.010
  57. 57.
    Y. H. Jouybari and F. Berkemeier, Electrochim. Acta, 2016, 217, 171 LINK https://doi.org/10.1016/j.electacta.2016.09.040
  58. 58.
    M.-G. Jeong, M. Islam, H. L. Du, Y.-S. Lee, H.-H. Sun, W. Choi, J. K. Lee, K. Y. Chung and H.-G. Jung, Electrochim. Acta, 2016, 209, 299 LINK https://doi.org/10.1016/j.electacta.2016.05.080
  59. 59.
    V. Etacheri, O. Haik, Y. Goffer, G. A. Roberts, I. C. Stefan, R. Fasching and D. Aurbach, Langmuir, 2012, 28, (1), 965 LINK https://doi.org/10.1021/la203712s
  60. 60.
    J. H. Ryu, J. W. Kim, Y.-E. Sung and S. M. Oh, Electrochem. Solid-State Lett., 2004, 7, (10), A 306 LINK https://doi.org/10.1149/1.1792242
  61. 61.
    Y. Deng, L. Ma, T. Li, J. Li and C. Yuan, ACS Sustain. Chem. Eng., 2019, 7, (1), 599 LINK https://doi.org/10.1021/acssuschemeng.8b04136
  62. 62.
    M. Armand and J.-M. Tarascon, Nature, 2008, 451, (7179), 652 LINK https://doi.org/10.1038/451652a
  63. 63.
    F. Zheng, M. Kotobuki, S. Song, M. O. Lai and L. Lu, J. Power Sources, 2018, 389, 198 LINK https://doi.org/10.1016/j.jpowsour.2018.04.022
  64. 64.
    P. Albertus, S. Babinec, S. Litzelman and A. Newman, Nature Energy, 2018, 3, 16 LINK https://doi.org/10.1038/s41560-017-0047-2
  65. 65.
    D. E. Fenton, J. M. Parker and P. V Wright, Polymer, 1973, 14, (11), 589 LINK https://doi.org/10.1016/0032-3861(73)90146-8
  66. 66.
    Fast Ion Transport in Solids: Electrodes and Electrolytes Conference, 21st–25th May 1979, Lake Geneva, USA, eds. M. B. Armand, J. M. Chabagno, M. Duclot, P. Vashista, J. N. Mundy, G. K. Shenoy Elsevier, New-Holland, Amsterdam, 1979
  67. 67.
    W. Liu, N. Liu, J. Sun, P.-C. Hsu, Y. Li, H.-W. Lee and Y. Cui, Nano Lett., 2015, 15, (4), 2740 LINK https://doi.org/10.1021/acs.nanolett.5b00600
  68. 68.
    M. D. Tikekar, L. A. Archer and D. L. Kochk, Sci. Adv., 2016, 2, (7), e1600320 LINK https://doi.org/10.1126/sciadv.1600320
  69. 69.
    W. Zhou, S. Wang, Y. Li, S. Xin, A. Manthiram and J. B. Goodenough, J. Am. Chem. Soc., 2016, 138, (30), 9385 LINK https://doi.org/10.1021/jacs.6b05341
  70. 70.
    Y. Zhao, Z. Huang, S. Chen, B. Chen, J. Yang, Q. Zhang, F. Ding, Y. Chen and X. Xu, Solid State Ionics, 2016, 295, 65 LINK https://doi.org/10.1016/j.ssi.2016.07.013
  71. 71.
    J. C. Bachman, S. Muy, A. Grimaud, H.-H. Chang, N. Pour, S. F. Lux, O. Paschos, F. Maglia, S. Lupart, P. Lamp, L. Giordano and Y. Shao-Horn, Chem. Rev., 2016, 116, (1), 140 LINK https://doi.org/10.1021/acs.chemrev.5b00563
  72. 72.
    L. Fan, S. Wei, S. Li, Q. Li and Y. Lu, Adv. Energy Mater., 2018, 8, (11), 1702657 LINK https://doi.org/10.1002/aenm.201702657
  73. 73.
    X. Han, Y. Gong, K. Fu, X. He, G. T. Hitz, J. Dai, A. Pearse, B. Liu, H. Wang, G. Rubloff, Y. Mo, V. Thangadurai, E. D. Wachsman and L. Hu, Nature Mater., 2017, 16, (5), 572 LINK https://doi.org/10.1038/nmat4821
  74. 74.
    L. E. Marbella, S. Zekoll, J. Kasemchainan, S. P. Emge, P. G. Bruce and C. P. Grey, Chem. Mater., 2019, 31, (8), 2762 LINK https://doi.org/10.1021/acs.chemmater.8b04875
  75. 75.
    Y. Kim, A. Yoo, R. Schmidt, A. Sharafi, H. Lee, J. Wolfenstine and J. Sakamoto, Front. Energy Res., 2016, 4, 20 LINK https://doi.org/10.3389/fenrg.2016.00020
  76. 76.
    C. A. Geiger, E. Alekseev, B. Lazic, M. Fisch, T. Armbruster, R. Langner, M. Fechtelkord, N. Kim, T. Pettke and W. Weppner, Inorg. Chem., 2011, 50, (3), 1089 LINK https://doi.org/10.1021/ic101914e
  77. 77.
    G. Larraz, A. Orera and M. L. Sanjuán, J. Mater. Chem. A, 2013, 1, (37), 11419 LINK https://doi.org/10.1039/c3ta11996c
  78. 78.
    J. Schnell, F. Tietz, C. Singer, A. Hofer, N. Billot and G. Reinhart, Energy Environ. Sci., 2019, 12, (6), 1818 LINK https://doi.org/10.1039/c8ee02692k
  79. 79.
    L. Cheng, W. Chen, M. Kunz, K. Persson, N. Tamura, G. Chen and M. Doeff, ACS Appl. Mater. Interfaces, 2015, 7, (3), 2073 LINK https://doi.org/10.1021/am508111r
  80. 80.
    J. Schnell, T. Günther, T. Knoche, C. Vieider, L. Köhler, A. Just, M. Keller, S. Passerini and G. Reinhart, J. Power Sources, 2018, 382, 160 LINK https://doi.org/10.1016/j.jpowsour.2018.02.062
  81. 81.
    C.-L. Tsai, V. Roddatis, C. V. Chandran, Q. Ma, S. Uhlenbruck, M. Bram, P. Heitjans and O. Guillon, ACS Appl. Mater. Interfaces, 2016, 8, (16), 10617 LINK https://doi.org/10.1021/acsami.6b00831
  82. 82.
    H. Yamada, T. Ito and R. H. Basappa, Electrochim. Acta, 2016, 222, 648 LINK https://doi.org/10.1016/j.electacta.2016.11.020
  83. 83.
    S.-W. Baek, J.-M. Lee, T. Y. Kim, M.-S. Song and Y. Park, J. Power Sources, 2014, 249, 197 LINK https://doi.org/10.1016/j.jpowsour.2013.10.089
  84. 84.
    W. Zha, Y. Xu, F. Chen, Q. Shen and L. Zhang, Solid State Ionics, 2019, 330, 54 LINK https://doi.org/10.1016/j.ssi.2018.12.008
  85. 85.
    Y. Zhang, F. Chen, R. Tu, Q. Shen and L. Zhang, J. Power Sources, 2014, 268, 960 LINK https://doi.org/10.1016/j.jpowsour.2014.03.148
  86. 86.
    A. Manthiram, Y. Fu, S.-H. Chung, C. Zu and Y.-S. Su, Chem. Rev., 2014, 114, (23), 11751 LINK https://doi.org/10.1021/cr500062v
  87. 87.
    F. Li, Q. Liu, J. Hu, Y. Feng, P. He and J. Ma, Nanoscale, 2019, 11, (33), 15418 LINK https://doi.org/10.1039/c9nr04415a
  88. 88.
    Y. Yang, G. Zheng and Y. Cui, Chem. Soc. Rev., 2013, 42, (7), 3018 LINK https://doi.org/10.1039/c2cs35256g
 

The Authors


Sarah Ball is the Applications Innovation Manager, Battery Materials, at Johnson Matthey, UK. She is the technical lead for application testing equipment specification and testing development, working across Johnson Matthey’s new battery application testing facilities in Billingham (County Durham, UK) and Milton Park (South Oxfordshire, UK). She has been involved in work on a range of beyond lithium-ion and lithium-ion batteries projects. Previously she was involved in fuel cell research on novel cathode materials including assessment of electrochemical stability, performance and properties.


Joanna Clark is Head of Product Development, Battery Materials at Johnson Matthey. She obtained her PhD from University of Liverpool, UK. She is responsible for development of new products in the battery materials research group at Johnson Matthey.


James Cookson is a Research Manager at Johnson Matthey, Sonning Common. He obtained a DPhil in Inorganic Chemistry at the University of Oxford, UK. James leads Johnson Matthey’s research activities in battery technologies; exploring both Li-ion as well as next generation technologies.

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