Tellurium
A brittle metalloid recovered almost entirely as a byproduct of copper electrolytic refining. Used in thermoelectrics, free-machining steels and specialty semiconductors relevant to automotive thermal management and electronics.
Overview
Tellurium (symbol Te, atomic number 52) is a brittle, silvery-white metalloid with a density of about 6.24 g/cm³ and a melting point near 449.5°C. Global supply is structurally constrained because tellurium is not mined as a primary ore; it is recovered from anode slimes generated during copper electrorefining, with secondary contributions from lead refining. In automotive and mobility contexts, tellurium underpins bismuth telluride (Bi2Te3) thermoelectric modules used for localised cooling of ADAS cameras, LiDAR, battery packs and seat climate systems. Small tellurium additions improve machinability in free-cutting steels and copper alloys used for fittings and connectors. Cadmium telluride (CdTe) photovoltaics are programme-adjacent for plant and infrastructure solar rather than the vehicle BOM. Because output tracks copper refining rates and refining capacity is geographically concentrated, tellurium sits on critical-materials lists and can experience sharp price spikes when thermoelectric or solar demand rises.
Automotive Applications
Similar Materials
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Rare Earth Element
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Samarium
Rare Earth Element
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Antimony
Metalloid
A lustrous, brittle grey metalloid primarily used as an alloying agent to harden lead and as a chemical synergist in flame retardants.
Germanium
Metalloid
A brittle, silvery-grey metalloid recovered mainly as a byproduct of zinc and coal processing. Critical for infrared optics, fibre optics and compound semiconductors used in ADAS, LiDAR and night-vision systems.
Properties
Category
Type
Metalloid
Available Colors
Available Forms
Key Properties
- Key constituent of Bi2Te3 thermoelectrics
- Brittle metalloid; diamond-like and layered allotropes
- Almost exclusively a copper-refining byproduct
- Improves machinability in steels and copper alloys at low additions
- Supply inelastic vs primary copper output
- Critical raw material with volatile pricing
Technical Specifications
Density
6.24 g/cm³
Tensile Strength
Not typically used as a structural metal (brittle metalloid)
Temperature Resistance
Melts at ~449.5°C; Bi2Te3 thermoelectric modules typically operate from roughly -40°C to ~200°C depending on design
Sustainability
Sustainability Rating
Tellurium availability is tied to copper electrorefining anode-slime recovery. Manufacturing scrap from thermoelectric module production can be recycled, but end-of-life recovery from dispersed automotive coolers remains immature. Co-product economics and refining concentration elevate supply risk versus demand growth in thermoelectrics and CdTe solar.