SungEelHiTech

Lithium-ion batteries are a popular energy source for green technologies such as electric vehicles, as they can store energy in small spaces and remain efficient after hundreds or even thousands of charge cycles. These batteries are a key part of current efforts to replace petrol cars, which emit greenhouse gases. These same capabilities also make batteries suitable for power storage on the electric grid. However, this comes at a price, as the manufacturing process for batteries and their components produces CO₂ emissions.

The manufacturing process

The production of lithium-ion batteries for electric vehicles is more material-intensive than for conventional internal combustion engines, and the demand for battery materials is growing. At present, most lithium is still extracted from mines or underground salt deposits, and much of the energy used to extract and process it comes from carbon-emitting fossil fuels. In particular, deep mining releases 15 tonnes of CO₂ into the atmosphere for every tonne of lithium extracted.

The synthesis of the materials needed for production requires temperatures between 800 and 1,000 degrees Celsius - temperatures that can only be achieved cost-effectively by burning fossil fuels, which also increases CO₂ emissions.

The amount of CO₂ emitted during the long process of battery production depends largely on what materials are used, how they are sourced and what energy sources are used in the production process. The vast majority of lithium-ion batteries are produced in China, where coal is the primary energy source (coal emits roughly twice as much greenhouse gas as natural gas, which can also be used in high-temperature production).

As an example, the Tesla Model 3 has an 80 kWh lithium-ion battery. The CO₂ emissions from battery production range from 2.4 to 16 tonnes. How much is a tonne of CO₂? That's what a typical petrol car emits in just about 4000 km of driving!

Usability

Despite the environmental footprint of lithium-ion battery production, this technology is much more climate-friendly than alternatives.

In Hungary, the electric grid (a mix of fossil fuels and low-carbon energy sources such as wind, solar, hydro and nuclear) is cleaner than burning petrol, so driving an electric car emits less CO₂ than a petrol car. The fuel consumption equivalent of an electric vehicle powered by electricity generated in a coal-fired power plant is about 4 litres/100 km. So the dirtiest electric vehicle is roughly the same as the best petrol-powered vehicles available today.

And an electric vehicle powered by electricity generated from renewable energy sources can be significantly cleaner, with a fuel consumption equivalent in Hungary up to 2 litres/100 km.

When calculated on a full life cycle basis (i.e. including the initial emissions associated with battery production), electric cars still emit less CO₂ than petrol cars. This is a key feature as the transport sector produces a very significant share of greenhouse gas emissions.