Published October 16, 2026, The Guardian’s investigation traced nickel ore from two Sulawesi mines through processing routes linked to battery suppliers and automakers. It did not identify a shipment from either mine in a particular car battery.
From Sulawesi ore to battery materials
The investigation traced limonite, a nickel-bearing ore, from the Cahaya and Hengjaya mines to a Morowali facility operated by a Zhejiang Huayou Cobalt subsidiary. There, the ore is processed into mixed hydroxide precipitate (MHP), a feedstock used to make battery cathodes.
Sulawesi Cahaya Mineral (SCM), which operates Cahaya, delivered 11 million tonnes of limonite to Huayou’s smelter in 2024 and nearly 12.5 million tonnes in 2025, according to The Guardian. Huayou confirmed group-level supply to battery maker CATL in response to a 2024 Shanghai Stock Exchange inquiry. The reported routes also connect Huayou to LG through Poland.
Those links describe a path through mining, processing and battery-material supply. They do not identify the contents of an individual vehicle battery.
What the forest analyses estimate
The TreeMap’s spatial analysis, as reported by The Guardian, estimated that nickel mining may account for about two-thirds of forest loss since 2001 within the Cahaya concession and more than half within Hengjaya. The Cahaya concession covers 21,000 hectares.
For 2024, the Indonesian nonprofit Auriga attributed 330 hectares of additional forest clearing to SCM. The Guardian also reported two administrative sanctions over more than 450 hectares cleared beyond permitted limits.
The figures describe different findings: The TreeMap’s estimates cover forest loss within the two concessions over the analysis period, while Auriga’s figure concerns additional clearing attributed to SCM in 2024. Neither turns a reported supplier connection into a match between a mine shipment and a particular car.
How far the supplier links reach
The Guardian named Volkswagen, Volvo Cars, Ford, General Motors, Tesla, BMW, Stellantis and Hyundai as end users of Huayou cathodes or recipients of CATL shipments. It separately linked Mercedes-Benz to Huayou. The companies’ positions in those supply chains differ, and the report did not connect any named automaker’s specific car battery to nickel from Cahaya or Hengjaya.
Renault Group told The Guardian that it had identified a nickel mining site in Sulawesi as an indirect supplier in its battery supply chain and was checking environmental, social and governance information concerning SCM. That statement describes an indirect supply-chain link, not the contents of a particular vehicle battery.
European models point to different outcomes
A separate analysis reported by El País on May 7, 2025, modeled the forest footprint of European vehicle demand across eight metals through 2050. Its scenarios varied battery chemistry and vehicle-use assumptions; they are modeled European outcomes, distinct from the reported forest-loss estimates for Sulawesi.
| Scenario | Battery and vehicle-use assumptions | Modeled forest footprint by 2050 |
| High-deforestation scenario | Sustained sales trends; NMC 811 batteries prevalent | 118,000 hectares |
| LFP-dominant scenario | LFP batteries predominate | 37,300 hectares |
| LFP with shared cars and microcars | LFP predominates; shared cars and microcars are included | Just over 21,300 hectares |
El País’s scenario report shows how different chemistry and use assumptions produce different modeled footprints. NMC 811 is a nickel-containing chemistry; the comparison also models LFP-dominant cases. The European estimates address demand scenarios across eight metals, rather than forest loss at Cahaya or Hengjaya.
