The transition to electric vehicles (EVs) would require access to significant quantities of technology metals, essential for the manufacture of EV components, such as electric powertrains and batteries. It is vital to understand different types of electric vehicles, electric traction motors and their composition of technology metals because the changing composition of electric vehicles over time creates challenges for end-of-life management and monitoring the flows and stocks.
Figure 1: Types of electric vehicles
Source: https://chargewizard.com/news/what-are-the-different-types-of-electric-vehicle
Hybrid electric vehicles (HEVs) and Plug-in hybrid electric vehicles (PHEVs) are powered by both an electric traction motor and a combustion engine. HEVs can only be charged through regenerative braking. PHEVs can be charged not only through regenerative braking, but also through external power sources (a home charge point or a public charging station). Battery electric vehicles (BEVs) are zero-emissions vehicles powered by rechargeable batteries and electric traction motors without petrol or diesel engine. Instead of being powered by electricity stored in a battery, another new type of EV is the hydrogen Fuel Cell electric vehicle (FCEV) which relies on the electrochemical reaction between hydrogen and oxygen in a fuel cell stack to produce electricity.
Electric traction motors used in EVs can be classified into direct current motors (DC) and alternating current motors (AC) (see Figure 2). Permanent magnet motors, induction motors, and wound rotor motors are the main electric traction motors that dominate the EV market. Different model series of electric vehicles use different types of motors due to the cost of materials, power density, torque density and efficiency. Permanent magnet motors containing rare earth elements are the most commonly used motor, and their market share has been increasing in the past few years. In 2022, permanent magnet electric traction motors rose to 86% of the global EV market share over 84% in 2021 (IDTechEx, 2022).
Figure 2: Classification of electric traction motors in EVs
Note: Types of electric traction motors that contain permanent magnets are highlighted in light blue colour
Table 1 shows the amount of key technology metals in terms of mass in grams by different types of electric vehicles. The composition of different types of EVs varies due to the different drivetrains and batteries used in the EVs.
Table 1 : Composition of key technology metals in EVs
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