Scientists from Singapore’s Nanyang Technological University have developed a new technology that transforms waste paper into an important component of lithium-ion batteries.
The technology converts paper into pure carbon through a process called carbonization. Nanyang Technological University researchers turned the paper’s fibers into electrodes that could be made into rechargeable batteries to power mobile phones, medical devices and electric vehicles.
To carbonize the paper, the team exposed the paper to high temperatures, reducing it to pure carbon, water vapor and oil. Since carbonization takes place in the absence of oxygen, the amount of carbon dioxide emitted is negligible, and the process is more environmentally friendly than disposing of kraft paper through incineration, which produces large amounts of greenhouse gases.
Carbon anodes produced in this way also exhibit excellent durability, flexibility, and electrochemical properties. Laboratory tests have shown that the anode can be charged and discharged 1,200 times, which is at least twice as durable as the anode of current mobile phone batteries. Batteries using NTU-made anodes are also able to withstand more physical stress than comparable products, absorbing stress five times better than similar products.
The method developed at NTU also uses less energy-intensive processes and heavy metals than current industrial methods for making battery anodes. Since the anode accounts for 10% to 15% of the total cost of a lithium-ion battery, this latest method, using low-cost scrap, is also expected to reduce the cost of making the battery.
The findings were published in the scientific peer-reviewed journal Rapid Manufacturing in October.
Data shows that paper waste, including discarded paper bags, cardboard, newspapers and other paper packaging, accounted for nearly one-fifth of the waste generated in Singapore in 2020.
