Investigation links Indonesian nickel mines to forest loss and battery supply chains

The story in brief

What you need to know

• The investigation traced ore from Cahaya and Hengjaya to a Huayou-operated smelter in Morowali and then to Chinese processing. It reported further links to battery and car companies, but said public records lack the shipment volumes and timing needed to connect specific ore to particular CATL batteries.1
• TreeMap’s spatial analysis, as reported by the Guardian, attributed around two-thirds of forest loss since 2001 within the Cahaya concession, and more than half within Hengjaya, to nickel mining. These are reported estimates; the underlying analysis was not included in the supplied sources for independent checking.1
• A separate Auriga analysis cited by the Guardian found that Sulawesi Cahaya Mineral contributed to the clearing of 330 hectares of forest in 2024. The investigation also described forest loss in woodlands inhabited by Tolaki people, but the available reporting does not establish the legal status or boundaries of land rights in the specific concessions.1
• A peer-reviewed study of 7,721 Sulawesi villages from 2011 to 2018 found that deforestation nearly doubled in nickel-mining villages. It also reported varied well-being outcomes: some measures, including environmental well-being, deteriorated, while infrastructure and living standards improved in some settings.2
• The carmakers quoted by the Guardian described due-diligence or review processes; Volkswagen said it could not rule out the companies being in its supply chain. The Guardian reported that Tesla, CATL, Huayou and the mine operators did not respond to its requests for comment.1

Conservation context

Why this matters

The reporting brings together forest-loss concerns and possible exposure within battery supply chains, but the evidence does not confirm that nickel from these mines reached any particular carmaker’s battery. A separate assessment of Morowali supply chains likewise describes likely industry links rather than definitive product-level provenance.13

The developing story

What happens next

Questions remain over whether the underlying forest analyses and spatial data will be available for independent review, and whether companies will publish site-audit findings or corrective actions. More detailed shipment records would also be needed to establish mine-to-battery provenance for a named vehicle or manufacturer.13

Established evidence

What we know

• The Guardian investigation describes a possible route from two Sulawesi mines through Indonesian and Chinese processing to battery and car companies.1
• The regional village-level study found increased deforestation in nickel-mining villages and mixed outcomes for community well-being.2
• A 2025 supply-chain assessment reported likely links between Indonesian nickel industries and electric-vehicle battery and car manufacturers, while cautioning that its mapping did not confirm nickel from the operations examined in specific vehicles.3

Open questions

What we don't know

• The available records do not establish whether nickel from Cahaya or Hengjaya entered any particular battery or vehicle.13
• The underlying TreeMap and Auriga analyses, methods and spatial datasets have not been provided in the supplied reporting for independent review.1
• The reporting does not establish customary land boundaries, consent or the specific impacts on Tolaki communities around the two concessions.1
• The available sources do not say whether the named manufacturers have completed site audits or taken corrective action, or whether they will publish findings.1

Source coverage

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