What value can be gained from end-of-life EV and hybrid rotor permanent magnet recycling?
Dr Michelle Lynch, member of the European Chapter Board of Directors International Precious Metals Institute (IPMI), provides us with her knowledge of how there is much to be gained from EOL EVs and Hybrids and it seems that magnets found within their rotors are a source of this value.
Permanent magnets are used in a variety of audio-visual equipment, electric motors, smartphones, power generation and other industrial applications. The main types are neodymium-iron-born (NdFeB), samarium-cobalt (SmCo), and ferrite.
NdFeB magnets are the strongest in existence and they are seeing exceptional growth in the automotive industry and wind power sector. These magnets also contain small quantities of valuable europium and terbium. They are arranged, for instance, as a set of 12 trapezoid-shaped magnets in a carousel which rotates relative to a conducting coil of wire, in doing so, inducing electricity – The typical composition and appearance of an EV NdFeB permanent magnet are shown in Figure 1.
Figure 1. Composition and Arrangement of a NdFeB EV Permanent Magnet
Many hybrids and full EV have NdFeB permanent magnets in their rotors. A selection is shown in Table 1. Hybrids such as the Toyota Prius contain smaller magnets whereas medium-sized, full BEV such as the Tesla Model 3 and the BMWi3 have magnets in the region of 1.5-2.0 kg.
Table 1. Selected PHEV and BEV with Magnet Sizes and Descriptions
|Vehicle Make/Model||Power/kW||Magnet/kg||Magnet Details|
|BMWi3||170||2.0||Permanent magnet AC synchronous electric, NdFeB sintered, two-pattern, parallel formation. 72 x 21.8 g (L) and 72 x 6.1g (S)|
|Chevy Bolt||200||1.57||Permanent magnet AC synchronous electric Double V formation, 256 x 6.1 g NdFeB sintered|
|Jaguar iPace||394||3.44||Permanent magnet AC synchronous electric, NdFeB sintered 168 x 11 g|
|Tesla Model 3||258||1.8||T3R Magnet Inner 96 x 9.1 g NdFeB sintered magnets and T3R Magner Outer 96 x 9.5 g NdFeB sintered magnets|
|Toyota Prius||90||0.50||Permanent magnet AC synchronous electric. 40 x 11g magnets per rotor Single V formation NdFeB sintered|
Source: Adapted from Bell, 2019
REE consumption in magnets was 37,000 tonnes in 2017 (Shaw and Constantinides 2017) and demand for NdFeB magnets alone is forecast to be almost 50,000 tonnes by 2030 (Bell, 2019). In addition, there is a significant market for these magnets in wind turbines. The current bid price of neodymium oxide is $50 per kg and praseodymium oxide is $55 per kg. Other REE are even more expensive – e.g., the dysprosium bid price is $266 per kg and terbium $517 per kg (Kitco 2019). Therefore, the amount of inherent value in the magnet population runs to the order of $ billions.
Figure 2. Permanent Magnet Strategic Metals Price History
As with EV batteries, in the next few years the major source of scrap will be from production rejects, swarf and residue, then further ahead, significant volumes from the end-of-life (EOL) material will be available. The issue, however, is whether an efficient recycling process can be developed in order to recover this value. To date, much permanent magnet scrap, mainly in portable electronics has unfortunately been lost to landfill. Recovery is further complicated by the fact that to protect the brittle magnet material from crumbling, they are covered either in plastic or a layer of Ni-Cu.
Supply and collection infrastructure aside, recycling technologies are also much less mature for magnets than for other valuable metal streams. However, pre-consumer material (swarf and residue) makes up 20-30% of the starting alloy (Worrell and Reuter, 2014).
The recovery route in this instance consists of roasting the “cutting sludge” to effect complete oxidation followed by standard refining techniques (solvent extraction, precipitation, and calcination). This allows Nd and Pr to be worked up as oxides or fluorides. Separation of the two elements then necessitates additional electrolysis or thermal treatment. This process is reportedly practised by Hitachi Metals who manufacture NEOMAX© NdFeB magnets; however, it is not widely practised, and it is thought that only 1% of pre-consumer magnet scrap is recycled (Liu and Chinnasamy, 2012).
There are few companies with mature commercial processes or capacity for post-consumer EOL permanent magnets. Green Cycle Systems – a subsidiary of Mitsubishi Electric in Japan has a recycling plant at Chiba that was set up in 2012 as part of a ¥ 5 billion government initiative to lower Japan’s dependence on Chinese supply of rare earths. (Japan Times, 2012). However, globally, the recycling rate of permanent magnets is very low. Some of the difficulties relate to removing the Ni-Cu plated coatings applied as part of the magnet finishing process, the brittle nature of the materials and the difficulty in identifying the compositions.
An effort is underway to come up with workable solutions to improving the future supply of CRM for magnets. Several initiatives have been running including The EU’s Horizon 2020 project SUSMAGPRO (Sustainable Recovery, Reprocessing, and Reuse of Rare-Earth Magnets in a Circular Economy) and the EU’s REE4EU project (2015-2019). (EU Cordis, 2019 and REE4EU, 2019). Stena Recycling, part of Stena Metall Group, headquartered in Sweden, is a participant looking to develop REE recycling and is involved in several projects.
Géoméga, based in Boucherville, Quebec, has been developing a proprietary magnet recycling process through its innovation arm (Innord). The process, called ISR, is organic solvent-free, does not create acid waste and recovers four high-price REE (i.e., neodymium, praseodymium, dysprosium, and terbium) from permanent magnets.
The chemical process requires the material to be ground up to fine powder which avoids the issue of removing the Ni-Cu and other types of coatings. The company claims that over 95% of the main reagents are recovered which makes the process effluent free while the main waste product, iron, is produced as a high purity by-product for sale.
This low-cost process is what allows the company to move towards further scaling up even in the current low-price environment for rare earth elements which are preventing new mine development. The company is nearing construction of a demonstration plant which will produce 450 kg per day of rare-earth oxides (REO) from 1.5 tonnes per day of NdFeB, SmCo manufacturing scraps as well as EOL scrap magnets.
The company expects to generate cash flow from this plant (Mugerman, 2020). It has raised US$1.2 million and has been at the stage of looking for offtake agreements and further funding based on its pilot plant results (Argus 2019).
A press release in February 2020 announced that the company had secured project debt financing of $1.72 m from the Quebec Government. The money will be used towards building a $3.2 m rare earth magnet recycling demonstration plant in St-Bruno-de-Montarville (Géoméga, 2020). Various other initiatives are ongoing for permanent magnet recycling (Lynch, 2019).
What the supply chain needs as these capabilities grow is to look to develop an efficient collection, first from OEM plants and any established smaller collection schemes and second from EOL EVs.
Considering the billion-dollar value in these magnets, it is likely that collectors can cash in on offering their services as upstream partners to companies such as Géoméga and other recyclers in Europe and North America developing REE recovery processes. These partnerships while profiting, also lower the ecological footprint of the EV supply chain which is a key strategic goal for the automotive industry.
The danger of not recycling is that producers will move to engineer-out the more expensive REE altogether – for instance, Toyota has developed a Nd-reduced magnet free of Tb and Dy. Instead, the formulation contains more of the low-cost rare earths – lanthanum and cerium (Toyota, 2019). While this balances supply and demand, it changes the recycling economics.
As ever, recyclers are faced with having to carefully catalogue different feed types and to have highly flexible business models. Reuse also has to be considered as an option when recycling margins are poor – and as with batteries, innovation for reuse of EV and energy magnets could prove to be a lucrative business opportunity.
Bell J.F., (2019); “Magnets in EV/HEV traction motors. Designs and state of the art manufacturing”; Baotou Tianhe Magnetics Technology Co Ltd.; The 16. International Rare Earth Conference of Metal Events Ltd.; 6th-8th November 2019
Diehl, O. et al; (2016); “Efficient Recycling of Rare Earth Permanent Magnets”; Laboratoryjournal.com, 25th Jan 2016
EU Cordis, (2019). “Sustainable Recovery, Reprocessing and Reuse of Rare-Earth Magnets in a Circular Economy (SUSMAGPRO).”
Japan Times (2012). “¥5 billion set for rare earth projects”, 9th February 2012
Géoméga (2020); “Geomega secures project debt financing of $1.72M from the Quebec Government”; Press Release, 9th Feb 2020
Liu J and Chinnasamy C. (2012). “Rare Earth Magnet Recycling.” Rare Earth Elements Workshop, 10th May 2012
Lynch M.K. (2019); “Recovery of Critical Materials from Recycling of EV Batteries, Fuel Cells and Renewable Power Systems — CRM Supply-Demand Challenges”; The Catalyst Review, September 2019
Mugerman, K. (2020). Private Communication
REE4EU. (2019). “Rare Earth Recycling Project for Europe.”
Shaw S. and Constantinides S. (2012). “Permanent Magnets: The Demand for Rare Earths.” Presented at the 8th International Rare Earths Conference; 13th–15th November (Hong Kong)
Toyota (2019); “Toyota develops new magnet for electric motors, aiming for 50 per cent reduction in use of critical rare-earth elements”; Press Release, 20th February 2019
About the author
Dr Michelle Lynch is Managing Director at Enabled Future Limited. She is a PhD in Chemicals and Catalysis and Fellow of the Royal Society of Chemistry (FRSC). She is a member of the IPMI European Chapter Board of Directors. Her 23 years of postdoctoral experience span catalyst R&D, precious metals market research, patent analysis and consulting. She is currently the Managing Director of Enabled Future Limited (EFL) – a consultancy which works on the safe and sustainable production, use and recycling of catalysts, advanced materials, renewable energy and power systems. Prior to setting up EFL, Michelle worked with IHS-Markit, Nexant and Johnson Matthey. She is passionate about sustainability, pollution abatement and helping to create high impact solutions to tackle climate change.
To contact Dr Lynch, please email her at email@example.com
If you would like to find out more about Enabled Future Ltd, please visit: www.enabledfuture.com