This article'slead sectionmay be too short to adequatelysummarize the key points. Please consider expanding the lead toprovide an accessible overview of all important aspects of the article.(October 2021)
1960s: Much of thebasic research that led to the development of theintercalation compounds that form the core of lithium-ion batteries was carried out in the 1960s byRobert Huggins andCarl Wagner, who studied the movement ofions in solids.[1] In a 1967 report by theUS military, plastic polymers were already used as binders for electrodes and graphite as a constituent for both cathodes and anodes, mostly for cathodes.[2]
1970s: Reversibleintercalation of lithium ions into graphite as anodes[3][4][5] and intercalation of lithium ions into cathodic oxide as cathodes[5][6][7] was discovered during 1974–76 byJürgen Otto Besenhard atTU Munich. Besenhard proposed its application in lithium cells.[8][9] What was missing in Besenhard's batteries is a solvent showing no co-intercalation into graphite, electrolyte decomposition and corrosion of current collectors. Thus, his batteries had very short cycle lives.
1970s: Reversible intercalation of lithium ions into layered cathode materials. British chemistM. Stanley Whittingham, then a researcher atExxonMobil, first reported a charge-discharge cycling with alithium metal battery (a precursor to modern lithium-ion batteries) in the 1970s.[5] Drawing on previous research from his time atStanford University,[10] he used a layeredtitanium(IV) sulfide as cathode andlithium metal as anode.[5][11] However, this setup proved impractical. Titanium disulfide was expensive (~$1,000 per kilogram in the 1970s) and difficult to work with, since it has to be synthesized under completely oxygen- and moisture-free conditions. When exposed to air, it reacts to formhydrogen sulfide compounds, which have an unpleasant odour and are toxic to humans and most animals. For this, and other reasons, Exxon discontinued development of Whittingham's lithium-titanium disulfide battery.[1]
Batteries with metallic lithium electrodes presented safety issues,most importantly the formation of lithiumdendrites, that internally short-circuit the battery resulting in explosions. Also, dendrites often lose electronic contact withcurrent collectors leading to a loss of cyclable Li+ charge.[12]Consequently, research moved to develop batteries in which, instead of metallic lithium, only lithiumcompounds are present, being capable of accepting and releasing lithium ions.
1973:Adam Heller proposed the lithium thionyl chloride battery, still used in implanted medical devices and in defense systems where a greater than 20-year shelf life, high energy density, and/or tolerance for extreme operating temperatures are required.[13] However, this battery employs unsafelithium metal and was not rechargeable.
The log number of publications about electrochemical powersources by year. lithium-ion batteries are shown in red. The magenta line is the inflation-adjusted oil price in US$/liter in linear scale.The number of non-patent publications about lithium-ion batteries grouped by authors' country vs. publication year.
1974: Besenhard was the first to show reversibility of Li-ion intercalation into graphite anodes, using organic solvents, including carbonate solvents.[5][14][3][4][6][7][8][9]
1976:Stanley Whittingham and his colleagues atExxon demonstrated what can be considered the first rechargeable "lithium-ion battery", although not a single component in this design was used in commercial lithium-ion batteries later.[15] Whittingham's cell was assembled in a charged state using lithium aluminum alloy as the negode, LiBPh4 (lithiumtetraphenylborate) indioxolane as the electrolyte and TiS2 as the posode. The battery useful cycle life was no more than 50 cycles. This design was based on Whittigham's earlier Li-metal batteries.[16]
1977: Samar Basu et al. demonstrated irreversible intercalation of lithium in graphite at theUniversity of Pennsylvania.[17][18] This led to the development of a workable lithium intercalated graphite electrode atBell Labs in 1984 (LiC 6)[19] to provide an alternative to the lithium metal electrode battery. However it was only a molten salt cell battery rather than a lithium-ion battery.
1978:Michel Armand introduced the term and a concept of arocking-chair battery,[20] where the same type of ion is de/intercalated into both positive and negative electrode during dis/charge. In the rocking-chair design solution-phase species do not appear in the reactionstoichiometry, which allows for minizing the amount of solvent in the battery, reduces the battery weight and cost.
1979: Working in separate groups, Ned A. Godshall et al.,[21][22][23] and, shortly thereafter,John B. Goodenough (Oxford University) andKoichi Mizushima (Tokyo University), demonstrated limited discharge-charge cycling of a 4 V cell made withlithium cobalt dioxide (LiCoO 2) as the positive electrode and lithium metal as the negative electrode.[24][25] This innovation provided the positive electrode material, which eventually became a component in the first commercial rechargeable lithium-ion battery.LiCoO 2 is a stable positive electrode material which acts as a donor of lithium ions, which means that it can be used with a negative electrode material other than lithium metal.[26] By enabling the use of stable and easy-to-handle negative electrode materials,LiCoO 2 enabled novel rechargeable battery systems. Godshall et al. further identified the similar value of ternary compound lithium-transition metal-oxides such as thespinel LiMn2O4, Li2MnO3, LiMnO2, LiFeO2, LiFe5O8, and LiFe5O4 (and later lithium-copper-oxide and lithium-nickel-oxide cathode materials in 1985)[27] Godshall et al. patentU.S. patent 4,340,652[28] for the use of LiCoO2 as cathodes in lithium batteries was based on Godshall's Stanford University Ph.D. dissertation and 1979 publications.
1980's: The negative electrode has its origins in PAS (polyacenic /polyacetylene semiconductive material) discovered by Tokio Yamabe and later by Shizukuni Yata in the early 1980s.[30][31][32][33] This development was inspired by an earlier discovery ofconductive polymers by ProfessorHideki Shirakawa and his group, and it could also be seen as having started from the polyacetylene lithium-ion battery developed byAlan MacDiarmid andAlan J. Heeger et al.[34]
1983:Rachid Yazami demonstrated the reversible electrochemical intercalation of lithium in graphite at room temperature usingpolyethylene oxide solvent.[35][36][37][38] The organic battery solvents, known at the time, decompose during charging with a graphite negative electrode. For this reason, Yazami used a solid electrolyte to demonstrate that lithium could be reversibly intercalated into graphite via an electrochemical mechanism at room temperature.
1983:Michael M. Thackeray,Peter Bruce, William David, and John B. Goodenough developedmanganesespinel, Mn2O4, as a charged cathode material for lithium-ion batteries. It has two flat plateaus on discharge, with lithium one at 4 V, stoichiometry LiMn2O4, and one at 3 V with a final stoichiometry of Li2Mn2O4.[39]
1985:Akira Yoshino demonstrated a rechargeable Li-ion battery using carbonaceous material (acetylene black), into which lithium ions could be inserted, as the negative electrode (anode) and lithium cobalt oxide (LiCoO2) as the positive electrode (cathode).[40] This dramatically improved safetyLiCoO2 and prepared Sony for commercial launch of a rechargeable lithium-ion battery 5 years later. Yoshino's design in 1985 was different from the final (1990) design in using 0.6 mol of LiClO4 (rather than LiPF6) in propylene carbonate (without ethylene or linear carbonate used currently to passivate the graphite negode) and in usingpolyacrylonitrile rather thanpolyvinylidene difluoride as the binder.
1986 : Around the same time as Akira Yoshino, Auborn and Barberio atBell Laboratory independently demonstrated another true rocking-chair battery assembled in the fully discharged state. Their 1.8 V lithium-ion battery comprised LiCoO2 as the posode, 1M LiPF6 inpropylene carbonate as the electrolyte and MoO2 as the negode.[41]
1986 :Asahi researchers, led by Akira Yoshino, demonstrated rechargeable battery with lithiumtetrafluoroborate (LiBF4) dissolved in a mixture of PC, gamma-butyrolactone (γBL) and ethylene carbonate (EC), as the electrolyte. The fluorinated anion turned out to be effective in passivating the Al current collector and compatible with the solvents, whileethylene carbonate (which is solid at room temperature and is mixed with other solvents to make a liquid) provided the necessarysolid electrolyte interphase on the anode, thus publicly disclosing the final piece of the puzzle leading to the modern lithium-ion battery.[42] This design was practically identical (except for LiBF4 being replaced with LiPF6, which is less reactive with the solvent(s)) to the one used in commercial lithium-ion batteries today.
1989:The recall of Moli Energy cells, comprising lithium metal, abruptly changed researchers’ perception in favor of heavier but safer dual-intercalation (i.e. lithium-ion rather than lithium-metal) batteries.[42]
1989-10-11:Jeff Dahn and two colleagues atMoli Energy inBurnaby (Canada) submit a journal article, proving a reversible intercalation of lithium ions into graphite in the presence ofethylene carbonate solvent (in 50:50 mixture withpropylene carbonate and with 1M LiAsF6 salt), and demonstrating the formation ofsolid electrolyte intephase on the first charge, followed by a reversible battery cycling.[47] This is essentially the composition, which will be used in commercial Li-ion batteries since 1992, except forLiAsF6 having been replaced with cheaper and less toxicLiPF6.
1990: The English term "lithium-ion battery", which was invented as a marketing tool to distinguish the new technology from ill-fatedlithium metal batteries appeared for the first time in a publication.[48] It was used bySony employees.[50]
In 2017 (2 years before the 2019 Nobel Prize in Chemistry was awarded)George Blomgren offered some speculations on whyAkira Yoshino's group produced a commercially viable lithium-ion battery beforeJeff Dahn's group:[51]
The Dahn group tested the carbonaceous positive electrode against lithium instead of a metal oxide. Therefore, they did not observe the severe corrosion of an aluminum positivecurrent collector with theLiAsF6 electrolyte, but Yoshino et al. used ...LiPF6, which was commonly used for primary lithium metal batteries in Japan.
Yoshino et al. also studied various binders including the ultimate winner-polyvinylidene fluoride, while Dahn's group used onlyethylene propylene diene monomer (EPDM), which turned out to be not durable enough for commercial LIBs.
Commercialization in portable applications: 1991-2006
The performance and capacity of lithium-ion batteries increased as development progressed.
1991:Sony andAsahi Kasei started commercial sale of the first rechargeable lithium-ion battery.[52] The Japanese team that successfully commercialized the technology was led by Yoshio Nishi.[53] 1991 ushered the Second Period (commercialization) in the history of lithium-ion batteries, which is reflected asinflection points in the plots "The log number of publications about electrochemical powersources by year" and "The number of non-patent publications about lithium-ion batteries" shown on this page. The battery employedsoft carbon (rather thangraphite) anode andLiCoO2 cathode. Sony's success with the development of lithium-ion battery manufacturing benefited from the company's prior experience with manufacturing monodisperse (20 μm) metal oxide microparticles and with coating processes formagnetic tapes.[54]
1994:iconectiv First commercialization of Li polymer by Bellcore.[55]
1994: The first aqueous Li-ion “rocking chair” chemistry was demonstrated by Dahn et al. It had a VO2 anode and LiMn2O4 cathode in a 5 M LiNO3 electrolyte with 1 mM LiOH.[56]
1996: Goodenough, Akshaya Padhi and coworkers proposedlithium iron phosphate (LiFePO4) and other phospho-olivines (lithium metal phosphates with the same structure as mineralolivine) as positive electrode materials.[57][58]
1996:Sony andNissan announced a partnership to develop a lithium-ion battery powered carFEV II with a 124-mile driving range.[59]
1998: C. S. Johnson, J. T. Vaughey, M. M. Thackeray, T. E. Bofinger, and S. A. Hackney report the discovery of the high capacity high voltage lithium-richNMC cathode materials.[60]
2001:Arumugam Manthiram and co-workers discovered that the capacity limitations of layered oxide cathodes is a result of chemical instability that can be understood based on the relative positions of the metal 3d band relative to the top of the oxygen 2p band.[61][62][63] This discovery has had significant implications for the practically accessible compositional space of lithium-ion battery layered oxide cathodes, as well as their stability from a safety perspective.
2001: Christopher Johnson, Michael Thackeray, Khalil Amine, and Jaekook Kim file a patent[64][65] forlithium nickel manganese cobalt oxide (NMC) lithium rich cathodes based on a domain structure.
2001: Zhonghua Lu andJeff Dahn file a patent[66] for the NMC class of positive electrode materials, which offers safety and energy density improvements over the widely used lithium cobalt oxide.
2002:Yet-Ming Chiang and his group atMIT showed a substantial improvement in the performance of lithium batteries by boosting theLiFePO4 material's conductivity bydoping it[67] withaluminium,niobium andzirconium. The exact mechanism causing the increase became the subject of widespread debate.[68]
2004:Yet-Ming Chiang again increased performance by utilizinglithium iron phosphate particles of less than 100 nanometers in diameter. This decreased particle density almost one hundredfold, increased the positive electrode's surface area and improved capacity and performance. Commercialization led to a rapid growth in the market for higher capacity lithium-ion batteries, as well as a patent infringement battle between Chiang andJohn Goodenough.[68]
2004: The number of non-patent publications about lithium-ion batteries fromPR China surpassed that from theUSA.Japan was the third leading country till 2011, when it was surpassed bySouth Korea.
2005: Y Song, PY Zavalij, andM. Stanley Whittingham report a new two-electron vanadium phosphate cathode material with high energy density[69][70]
Commercialization in automotive applications: 2006-today
2014: Commercial batteries from Amprius Corp. reached 650Wh/L (a 20% increase), using a silicon anode and were delivered to customers.[76]
2016:Koichi Mizushima and Akira Yoshino received the NIMS Award from theNational Institute for Materials Science, for Mizushima's discovery of the LiCoO2 cathode material for the lithium-ion battery and Yoshino's development of the lithium-ion battery.[77]
2016: Z. Qi, and Gary Koenig reported a scalable method to produce sub-micrometer sizedLiCoO 2 using a template-based approach.[78]
Learning curve of lithium-ion batteries: the price of batteries declined by 97% in three decades.[81][82]
Industry produced about 660 million cylindrical lithium-ion cells in 2012; the18650 size is by far the most popular for cylindrical cells. IfTesla were to have met its goal of shipping 40,000Model Selectric cars in 2014 and if the 85 kWh battery, which uses 7,104 of these cells, had proved as popular overseas as it was in the United States, a 2014 study projected that the Model S alone would use almost 40 percent of estimated global cylindrical battery production during 2014.[83] As of 2013[update], production was gradually shifting to higher-capacity 3,000+ mAh cells. Annual flat polymer cell demand was expected to exceed 700 million in 2013.[84][needs update]
Prices of lithium-ion batteries have fallen over time. Overall, between 1991 and 2018, prices for all types of lithium-ion cells (in dollars per kWh) fell approximately 97%.[81] Over the same time period, energy density more than tripled.[81] Efforts to increase energy density contributed significantly to cost reduction.[85]
In 2015, cost estimates ranged from $300–500/kWh.[clarification needed][86] In 2016 GM revealed they would be payingUS$145/kWh for the batteries in the Chevy Bolt EV.[87] In 2017, the average residential energy storage systems installation cost was expected to drop from $1600 /kWh in 2015 to $250 /kWh by 2040 and to see the price with 70% reduction by 2030.[88] In 2019, some electric vehicle battery pack costs were estimated at $150–200,[89] and VW noted it was payingUS$100/kWh for its next generation ofelectric vehicles.[90]
Batteries are used forgrid energy storage andancillary services. For a Li-ion storage coupled with photovoltaics and an anaerobic digestionbiogas power plant, Li-ion will generate a higher profit if it is cycled more frequently (hence a higher lifetime electricity output) although the lifetime is reduced due to degradation.[91]
Several types oflithium nickel cobalt manganese oxide (NCM) andlithium nickel cobalt aluminium oxide (NCA) cathode powders with a layered structure are commercially available. Their chemical compositions are specified by themolar ratio of component metals. NCM 111 (or NCM 333) haveequimolar parts of nickel, cobalt and manganese. Notably, inNCM cathodes, manganese is not electroactive and remains in theoxidation state +4 during battery's charge-discharge cycling. Cobalt is cycled between theoxidation states +3 and +4, and nickel - between +2 and +4. Due to the higher price of cobalt and due to the higher number of cyclable electrons per nickel atom, high-nickel (also known as "nickel-rich") materials (with Ni atomic percentage > 50%) gain considerable attention from both battery researchers and battery manufacturers. However, high-Ni cathodes are prone to O2 evolution and Li+/Ni4+ cation mixing upon overcharging.[92]
As of 2019[update], NMC 532 and NMC 622 were the preferred low-cobalt types for electric vehicles, with NMC 811 and even lower cobalt ratios seeing increasing use, mitigating cobalt dependency.[93][94][89] However, cobalt for electric vehicles increased 81% from the first half of 2018 to 7,200 tonnes in the first half of 2019, for a battery capacity of 46.3 GWh.[95]
In 2010, global lithium-ion battery production capacity was 20 gigawatt-hours.[96] By 2016, it was 28 GWh, with 16.4 GWh in China.[97] Production in 2021 is estimated by various sources to be between 200 and 600 GWh, and predictions for 2023 range from 400 to 1,100 GWh.[98]
^abBesenhard, J.O. & Fritz, H.P. (1974). "Cathodic Reduction of Graphite in Organic Solutions of Alkali and NR4+ Salts".J. Electroanal. Chem.53 (2):329–333.doi:10.1016/S0022-0728(74)80146-4.
^abBesenhard, J. O. (1976). "The electrochemical preparation and properties of ionic alkali metal-and NR4-graphite intercalation compounds in organic electrolytes".Carbon.14 (2):111–115.Bibcode:1976Carbo..14..111B.doi:10.1016/0008-6223(76)90119-6.
^abSchöllhorn, R.; Kuhlmann, R.; Besenhard, J. O. (1976). "Topotactic redox reactions and ion exchange of layered MoO3 bronzes".Materials Research Bulletin.11:83–90.doi:10.1016/0025-5408(76)90218-X.
^abBesenhard, J. O.; Eichinger, G. (1976). "High energy density lithium cells: Part I. Electrolytes and anodes".Journal of Electroanalytical Chemistry and Interfacial Electrochemistry.68:1–18.doi:10.1016/S0022-0728(76)80298-7.
^abEichinger, G.; Besenhard, J. O. (1976). "High energy density lithium cells: Part II. Cathodes and complete cells".Journal of Electroanalytical Chemistry and Interfacial Electrochemistry.72:1–31.doi:10.1016/S0022-0728(76)80072-1.
^Lithium-titanium disulfide rechargeable cell performance after 35 years of storage. 2015. J Power Sources. 280/18-22. N. Pereira, G.G. Amatucci, M.S. Whittingham, R. Hamlen. doi: 10.1016/j.jpowsour.2015.01.056.
^ELECTRICAL ENERGY-STORAGE AND INTERCALATION CHEMISTRY. 1976. Science. 192/4244, 1126-7. M.S. Whittingham. doi: 10.1126/science.192.4244.1126
^Basu, S.; Zeller, C.; Flanders, P. J.; Fuerst, C. D.; Johnson, W. D.; Fischer, J. E. (1979). "Synthesis and properties of lithium-graphite intercalation compounds".Materials Science and Engineering.38 (3):275–283.doi:10.1016/0025-5416(79)90132-0.
^US 4304825, Basu; Samar, "Rechargeable battery", issued 8 December 1981, assigned to Bell Telephone Laboratories
^1978 NATO conference on Materials for Advanced Batteries, Aussios, France. Cited from ISBN 978-1-61249-762-4. page 94.
^Godshall, N.A.; Raistrick, I.D.; Huggins, R.A. (1980). "Thermodynamic investigations of ternary lithium-transition metal-oxygen cathode materials".Materials Research Bulletin.15 (5): 561.doi:10.1016/0025-5408(80)90135-X.
^Godshall, Ned A. (17 October 1979) "Electrochemical and Thermodynamic Investigation of Ternary Lithium -Transition Metal-Oxide Cathode Materials for Lithium Batteries: Li2MnO4spinel, LiCoO2, and LiFeO2", Presentation at 156th Meeting of the Electrochemical Society, Los Angeles, CA.
^Godshall, Ned A. (18 May 1980)Electrochemical and Thermodynamic Investigation of Ternary Lithium-Transition Metal-Oxygen Cathode Materials for Lithium Batteries. Ph.D. Dissertation, Stanford University
^Mizushima, K.; Jones, P. C.; Wiseman, P. J.; Goodenough, J. B. (1980). "Li xCoO 2(0<x<-1): A new cathode material for batteries of high energy density".Materials Research Bulletin.15 (6):783–789.doi:10.1016/0025-5408(80)90012-4.S2CID97799722.
^Godshall, N. A.; Raistrick, I. D. and Huggins, R. A.U.S. patent 4,340,652 "Ternary Compound Electrode for Lithium Cells"; issued 20 July 1982, filed by Stanford University on 30 July 1980.
^CYCLABLE LITHIUM ORGANIC ELECTROLYTE CELL BASED ON 2 INTERCALATION ELECTRODES. 1980. J Electrochem Soc. 127/3, 773-4. M. Lazzari, B. Scrosati. doi: 10.1149/1.2129753
^Yamabe, T. (2015)."Lichiumu Ion Niji Denchi: Kenkyu Kaihatu No Genryu Wo Kataru" [Lithium Ion Rechargeable Batteries: Tracing the Origins of Research and Development: Focus on the History of Negative-Electrode Material Development].The Journal Kagaku (in Japanese).70 (12):40–46. Archived fromthe original on 8 August 2016. Retrieved15 June 2016.
^Novák, P.; Muller, K.; Santhanam, K. S. V.; Haas, O. (1997). "Electrochemically Active Polymers for Rechargeable Batteries".Chem. Rev.97 (1):271–272.doi:10.1021/cr941181o.PMID11848869.
^Thackeray, M. M.;David, W. I. F.; Bruce, P. G.; Goodenough, J. B. (1983). "Lithium insertion into manganese spinels".Materials Research Bulletin.18 (4):461–472.doi:10.1016/0025-5408(83)90138-1.
^US 4668595, Yoshino; Akira, "Secondary Battery", issued 10 May 1985, assigned to Asahi Kasei
^Padhi, A.K., Naujundaswamy, K.S., Goodenough, J. B. (1996) "LiFePO4: a novel cathode material for rechargeable batteries".Electrochemical Society Meeting Abstracts, 96-1, p. 73
^Journal of the Electrochemical Society, 144 (4), p. 1188-1194
^Dennis Normile, "Lithium-ion hits the road". Popular Science 248/4 (April 1996):45.
^C. S. Johnson, J. T. Vaughey, M. M. Thackeray, T. E. Bofinger, and S. A. Hackney "Layered Lithium-Manganese Oxide Electrodes Derived from Rock-Salt LixMnyOz (x+y=z) Precursors" 194th Meeting of the Electrochemical Society, Boston, MA, Nov.1-6, (1998)
^Chebiam, R. V.; Kannan, A. M.; Prado, F.; Manthiram, A. (2001). "Comparison of the chemical stability of the high energy density cathodes of lithium-ion batteries".Electrochemistry Communications.3 (11):624–627.doi:10.1016/S1388-2481(01)00232-6.
^Chebiam, R. V.; Prado, F.; Manthiram, A. (2001). "Soft Chemistry Synthesis and Characterization of Layered Li1−xNi1−yCoyO2−δ (0 ≤ x ≤ 1 and 0 ≤ y ≤ 1)".Chemistry of Materials.13 (9):2951–2957.doi:10.1021/cm0102537.
^Song, Y; Zavalij, PY; Whittingham, MS (2005). "ε-VOPO4: electrochemical synthesis and enhanced cathode behavior".Journal of the Electrochemical Society.152 (4):A721 –A728.Bibcode:2005JElS..152A.721S.doi:10.1149/1.1862265.
^Lim, SC; Vaughey, JT; Harrison, WTA; Dussack, LL; Jacobson, AJ; Johnson, JW (1996). "Redox transformations of simple vanadium phosphates: the synthesis of ϵ-VOPO4".Solid State Ionics.84 (3–4):219–226.doi:10.1016/0167-2738(96)00007-0.
^Qi, Zhaoxiang; Koenig, Gary M. (16 August 2016). "High-Performance LiCoO2Sub-Micrometer Materials from Scalable Microparticle Template Processing".ChemistrySelect.1 (13):3992–3999.doi:10.1002/slct.201600872.
^Lai, Chun Sing; Jia, Youwei; Lai, Loi Lei; Xu, Zhao; McCulloch, Malcolm D.; Wong, Kit Po (October 2017). "A comprehensive review on large-scale photovoltaic system with applications of electrical energy storage".Renewable and Sustainable Energy Reviews.78:439–451.Bibcode:2017RSERv..78..439L.doi:10.1016/j.rser.2017.04.078.
^A review of the degradation mechanisms of NCM cathodes and corresponding mitigation strategies. 2023. J Energy Storage. 73/27. L. Britala, M. Marinaro, G. Kucinskis. doi: 10.1016/j.est.2023.108875.
^"What do we know about next-generation NMC 811 cathode?".Research Interfaces. 27 February 2018.Industry has been improving NMC technology by steadily increasing the nickel content in each cathode generation (e.g. NMC 433, NMC 532, or the most recent NMC 622)
