The new battery manufacturing process is environmentally friendly

Switching from gas-powered cars to electric cars is one way to reduce carbon emissions, but manufacturing the lithium-ion batteries that power these electric cars can itself be an energy-intensive and polluting process. Now researchers at Dalhousie University have developed a manufacturing process that is cheaper and greener.

“Manufacturing lithium-ion cathode materials consumes a lot of energy and water and produces waste. This material has the greatest impact on the environment, especially CO2.₂ Battery footprint.

We wanted to see if there were more environmentally friendly, sustainable and less expensive ways to make these materials.

Most electric vehicle batteries use lithium nickel nickel cobalt oxide (NMC), the elements of which are mixed in the crystal structure of the cathode. They are usually made by dissolving the elements in water and then using the crystals that form when the elements solidify.

This process requires a lot of water – which must then be treated to clean it – and energy, which is the main source of the batteries’ cost and carbon footprint. Using the Canadian Light Source (CLS) at the University of Saskatchewan, Obrovac and his team investigated whether they could use a completely dry process to achieve the same results while saving energy, water and money.

Their work has been published in two papers, in ACS Omega And Journal of Electrochemical Society.

“We wanted to see if you could take the dry ingredients and combine them with simple processes that you would find in any large factory and heat them up, could you get the same quality?” he says. “And under what conditions can you do this to obtain trade materials while cutting off water and waste?”

Cathodes made from dry materials are sometimes not as homogeneous as cathodes made in water, so the team tried different methods using different oxides and thermal regimes at different temperatures and pressures to determine what worked best.

They used the Brockhouse beamline at CLS to look inside the furnace and performed various experiments to see exactly what was happening during the process. “What we found was important information about how we can improve the process so that what comes out is a higher-grade NMC-type cathode material,” says Obrovac.

The highest quality cathodes currently available are made of single crystals with particles about 5 microns in diameter. By fine-tuning the raw materials and furnace conditions, the Obrovac team was able to reproduce those qualities using a completely dry process, comparing the cathode materials to the best materials on the market today.

Obrovac has partnered with Nova Scotia-based battery company NOVONIX, which uses dry processes to produce cathode materials at the company’s test facility in Dartmouth. The facility is capable of producing 10 tons of cathode material per year, with methods that have 30% lower capital costs than conventional (wet) methods, 50% lower operating costs, and 25% lower energy consumption, while requiring no process. . Zero water and waste generation.

“These are big numbers, it’s a very big change in the production of these battery materials,” says Obrovac. “In general, lower-cost batteries should have significantly lower global warming footprints.”