Due to the falling price of silicon solar cells, as well as their manageable size, the sight of solar panels on household rooftops has become a familiar one. However, solar energy, as many other sustainable forms of energy, is intermittent. At peak moments, such as on sunny summer days, the grid is flooded with solar energy, while during the evening and in winter, when energy tends to be most in demand, supply is less. In order to secure energy availability on demand, storage needs to be integrated into the grid.

The pumped hydroelectric storage plant is one example of widespread technology for storing energy by pumping water from a lower reservoir to a higher one, and electricity is generated on demand by letting the water flow back through turbines. The expansion of these plants, however, is limited by the amount of suitable geographical sites. A technology that does not bear these constraints is the electrochemical battery. Lithium-ion batteries present in everyday electronics are examples of these. On a larger scale, companies are starting to invest in large batteries supporting the grid. The dominant technology for such large batteries is currently lithium iron phosphate (LFP). A report by the International Energy Agency (IEA) predicts lithium demand to multiply by more than 40 times in 2040 compared to 2020, largely caused by this need. Lithium mining, however, comes with considerable geopolitical and humanitarian concerns. If lithium mining has a significantly negative impact on........

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