Energy consumption is reduced by 90%, gas emissions are reduced by 75%, and lithium battery recycling research has achieved breakthroughs

Lithium Grid News: A research project conducted by nano-engineers at the University of California, San Diego, focused on researching the recycling technology of cathode batteries made of lithium iron phosphate. By reducing heavy metals such as nickel and cobalt, these types of batteries can help avoid the degradation of the landscape and water sources of the mining area, and at the same time prevent workers from being exposed to dangerous conditions during mining.

Most of today's lithium batteries use the rare and expensive metal cobalt as part of the cathode, but mining this material will bring a huge price to the environment. Therefore, scientists have been working to find more environmentally friendly alternative materials, and lithium phosphate is one of them. According to reports, the latest research can further improve its environmental performance, once it is used up, it can be restored to its original state with a little energy.

The increasing awareness of cobalt-related issues is driving changes in the industry. Many people are looking for alternative battery designs, including large companies such as IBM and Tesla. . This year, Tesla started selling Model 3 with lithium iron phosphate batteries. These batteries are safer, have a longer life, and are cheaper to produce, but one of the disadvantages is that once they are used up, the cost of recycling is high.

'Recycling them is not cost-effective,' said Zheng Chen, professor of nanoengineering at the University of California, San Diego. 'This is the same as the dilemma of plastics-materials are cheap, but the method of recycling them is not cheap. 'The breakthroughs in this research are mainly focused on several mechanisms behind the performance degradation of lithium iron phosphate batteries. When they are recycled, this process will promote structural changes. With the loss of lithium ions, vacancies are created in the cathode, and iron and lithium ions will also exchange positions in the crystal structure. This will trap lithium ions and prevent them from circulating in the battery.

The research team used commercially available lithium iron phosphate batteries and consumed half of the storage capacity. Then, they disassembled the battery, soaked the resulting powder in a solution containing lithium salt and citric acid, then washed it, dried it, and heated it at a temperature of about 60 to 80°C. The powder was then made into a new cathode and tested in button batteries and pouch batteries. The research team found that its performance had returned to its original state.

The researchers pointed out that this is because this recycling technology can not only supplement the battery’s lithium ion reserve, but also return the lithium ions and iron ions to their original positions in the cathode structure. This is due to the addition of citric acid, which provides electrons for iron ions and reduces the positive charge that prevents iron ions from moving to their original positions. The result of all this is that lithium ions can be released and recycled through the battery again. According to this study, compared with the current method of recycling lithium phosphate batteries, this technology consumes 80% to 90% less energy and emits about 75% less greenhouse gases. Although this is a good start, the research team said that further research is needed to determine the overall environmental footprint of collecting and transporting large numbers of such batteries.

'The next challenge will be to figure out how to optimize these processes,' Zheng Chen said. 'This will bring this recycling process closer to industry adoption.'