Nickel mining, processing and refining carry significant environmental impacts, and LCA quantifies both the direct emissions and the embodied impacts of the energy, chemicals, reagents and transport involved, which matters most for reagent- and energy-heavy routes. LCA is increasingly the standard way to compare the environmental performance of different routes to a similar product, and regulation is accelerating its adoption: the EU Battery Regulation is the first legislation to embed LCA at its core, and that pressure on battery makers is flowing upstream to nickel sulphate producers. Decarbonisation options differ by ore. Sulphide operations hold an intriguing possibility, the ultramafic minerals in their tailings (brucite, serpentine, olivine) can react with CO₂ to form stable carbonates, potentially sequestering carbon, though the process is energy-intensive and may simply shift emissions from Scope 1 to Scope 2. Laterite operations face the difficulty of integrating renewable energy in remote, often tropical or mountainous regions where infrastructure is limited and the high-temperature, high-pressure processing needs continuous power. In both cases, LCA is what reveals the real trade-offs and guards against shifting emissions from one part of the chain to another.