Batteries have always been a problematic waste stream, which has been exacerbated over the past five years due to the advent of electric vehicles (EVs) and the introduction of Energy Storage Systems for both residential and utility applications. This means that over the next 10 years the level of battery waste that will need reprocessing and recycling will grow significantly in volume. Batteries are complex industrial products, and the mix of materials batteries are made of deliver great benefits – but not without also introducing a number of unique problems. The products that cause most concern are those with a lithium-ion component, which has caused a lot of fires in MRFs and rubbish trucks. These batteries are dangerous due to way in which they combust – that is known as thermal runaway. High volumes of water are required to cool ignited batteries – which is a different strategy than for traditional fires.
There have been a lot of ideas put forward to try and solve the issue around end-of-life batteries, and the level of industry and academic collaboration continues to slowly grow. Then there is the Battery Stewardship Council, which does great work with its B-cycle initiative that includes many collection points around the country.
At the Australian Battery Recycling and Manufacturing Summit held in Sydney recently, another aspect covered was the place research and technology have in the world of battery resource recovery. That research includes the development of efficient processes to both break down modern batteries and to chemically treat waste streams to recover critical minerals.
Chaired by Nicholas Assef, founder and chief executive officer of Battery Pollution Technologies, a panel made up of Professor Deepak Dubal, Academic Lead International and Engagement at Queensland University of Technology; Professor Scott Donne, Professor of Electrochemistry & Energy Storage at the University of Newcastle; and Greg Leach, founder and CEO of Blockhead Technologies, discussed some of the latest technologies and research that can help make batteries part of a circular economy with minimal impact on the environment.
Donne led the discussion by giving a breakdown of what materials make up lithium-ion batteries, which also gave in indication of what can be recovered when they reach end of life.
“The original lithium-ion battery material was lithium titanium disulphide,” he said. “The first commercial system was a lithium cobalt dioxide cathode material. It was originally started with lithium metal as the anode material, but quite quickly morphed into a carbon-based material as the anode system.
A lot of work has since been spent dealing with safety, stability and cyclability issues with various cathode materials.
“Lithium-ion phosphate is a relatively recent development. Within the cobalt dioxide there’s been dilutions with replacing some of the cobalt with nickel and manganese. Some aluminium goes in there as well.
They’re the most common chemistries used. Typically, lithium cobalt dioxide operates at around 3.7 volts in terms of operating voltage, and the capacity of that system is quite a bit more than the lithium-ion phosphate system. A lot of work has gone into the development of lithium-ion phosphate. Its energy density is not so high.”
When it comes to the recycling of the battery material, Donne said his department has several ongoing projects involving corporate sponsors. His team has been doing a lot of work with batteries, capacitors and has recently finished up with some fuel
cell research.
One project has been the development of materials that go into batteries that power implantable pacemakers.
These new materials mean the batteries last longer so the increase in time between surgery to implant a pacemaker has increased by one to
two years.
With such an increase in battery life, it means end of life of the device has been extended, and therefore reduces the amount of waste that will go to landfill from the components that cannot be recovered. But there is more.
“From a recycling point of view, let’s compare recycling with primary metal production,” said Donne. “The ores that you collect out of the ground containing nickel and cobalt, they’re quite dilute. But from a battery material recycling point of view, if you have recycled batteries, they’re very rich in the elements that you want to extract. Very rich in cobalt, very rich in nickel and lithium, way richer than an ore out of the ground. It makes the processing easier because it’s much more concentrated.”
Assef went one step further when explaining the benefits of recycling over virgin feedstock.
“From a recycling perspective, you have a leg up because you’re recycling a more pure material than what Mother Nature is developing, which has been going through a whole series of processes to get to a battery-ready state,” he said.
Although Dubal is a scientist, he thinks breakthrough research should be looking at the issue from a battery recycling perspective. In other words, the industry should be developing a battery recycling process that is efficient and economically feasible and sustainable. The result would be a sustainable battery industry with a reduced environmental footprint.
However, he also feels there has been no real developments in the recycling and recovery process for batteries.
It is a case of crushing it, getting the black mass (or left over) and then leaching and separating it. One of the main problems with trying to separate the different elements is that it’s hard to do because they are all similar in terms of where they sit on the periodic table.
“The cost of separation is hard because it’s very difficult to separate nickel, cobalt and lithium, because all
of them have the same chemistry,” Dubal said. “All of them are from the same row of the periodic table. It means the atomic numbers are very close, which means the chemical properties are very close. It’s very difficult to separate those chemicals or prepare the new precursors.”
Dubal also spoke of a seminar he attended where one of the speakers compared the carbon footprint of manufacturing a new battery to recycling an old one. The speaker gave evidence that indicated that the difference was negligible. This type of example made Dubal think that scientists need to be thinking about issues like this when researching better ways to recycle batteries.
While there is research into how to best dispose of, or recycle and/or reuse batteries, there are also practical considerations that need to be taken into account, according to Assef.
While handling your everyday Eveready, Duracell or Energizer AA or AAA batteries is not seen as too manually intensive, the same can’t be said for the next generation of EV batteries.
“It’s not very easy recycling large-scale lithium batteries as it needs to be efficient,” he said. “[We have to look at] the technology opportunities around automation.
“I mean if you’re sitting in front of these heavy vehicle batteries, how do you physically move those around the floor of a recycling site? How much space do you have to store those batteries? And what is your cycle rate when taking the battery in, and then moving it out?”
This led Assef to bring up robotics, and he queried Dubal about that aspect of recycling batteries. Dubal pointed out again that separating the cathode and anode instead of crushing the whole battery would be ideal. He believes that Australia could lead the way in terms of robotics being a great platform to do so.
“The automation and robotics [could] have a really great role,” he said. “Of course, there is not very much research around this space. But I would say that is a really great opportunity in terms of the Australian context.”
Then there is the ESG (environmental, social and governance) aspects that a lot of companies are now trying to initiate to get social license within local communities.
Leach said one of the keys is metadata – getting information about a product can be helpful when it comes to disposal. Blockhead Technologies does a lot of work with a gold refiner in Sydney. It helps the industry with its ESG by being able to provide provenance of where an ingot of gold comes from, where it has been refined, plus an array of other data. He calls it a gold passport.
The same process can be put together for batteries, said Leach. It would help with auditability of batteries, as well as transparency of what elements are in a product.
And what does the future hold in terms of research, development and new technologies in the battery space?
“As long as there is a demand for improvement in technology, there will always be ongoing R&D to make that happen,” said Donne. “And if that involves the development of new systems, new chemistries associated with battery technologies, then that’s the approach that is going to be needed to address the deficiency that’s perceived in a particular technology. That goes hand-in-hand with the downstream processes that will be required to respond to, for example, the production of batteries. If your cathode material, for example, has to be of a certain composition or physical characteristics, then that process has to adapt to that if it wants to be used and to be sustainable That will have to be the case for a recycling process as well.”
This session concluded with Assef highlighting the need for proactive involvement of government in developing specific narrow grants that can benefit the battery recycling and recycling technology industries – including leading to the development of exportable technologies.