The Future Of


Episode Summary

Are batteries key to a renewable energy future? Experts Jacques Eksteen and Terry Humphries discuss the future of battery technology and the important role Australia has to play.

Episode Notes

For decades, inefficient batteries prevented a large-scale shift to renewable energy sources like solar and wind, because they couldn’t store enough energy to tide us over when the sun wasn’t shining or the wind wasn’t blowing.

But that’s all changed. Lithium battery technology has evolved to the point where we could feasibly – with progressive leadership – abandon fossil fuels within the next few decades.

Hydrogen storage is another technology that could emerge as a viable alternative to lithium batteries before long, futher fueling the renewable revolution.

David is joined by Professor Jacques Eksteen from the Future Battery Industries Cooperative Research Centre and Dr Terry Humphries, a Curtin research fellow and chemist with a particular interest in hydrogen storage.

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You can read the full transcript of the episode here.

Episode Transcription

Intro (00:00):

This is The Future Of, where experts share their vision of the future and how their work is helping shape it for the better.

David (00:11):

I'm David Blayney. For decades, inefficient batteries prevented a large scale shift to renewable energy sources such as solar and wind because they couldn't store enough energy to tide us over while the sun wasn't shining or the wind wasn't blowing. But now that's all changed. Of course, lithium battery technology has evolved to the point where we could feasibly, with the right leadership, abandon fossil fuels within the next few decades. Hydrogen storage is yet another technology that could emerge as a viable alternative to lithium batteries before long, further fueling the renewable revolution. Today I'm connected to Professor Jacques Eckstein, the chief operating officer for the Future Battery Industries Cooperative Research Centre, and Dr Terry Humphreys, a Curtin research fellow and a chemist with a particular interest in hydrogen storage. Thank you very much for your time, Jacques and Terry.

Professor Jacques Eksteen (01:09):

Thank you David.

David (01:11):

So the battery boom ... it's pretty good news for both the planet and for Western Australia, isn't it?

Professor Jacques Eksteen (01:17):

Yes, I think so. I think we've got - there's a planet story, there's an Australia story and there's a Western Australian story. I think also, one has to separate ... there's also a health story and an environmental story. So well - let's just maybe touch upon these different aspects at the, at the planet level, if it becomes one of the key enablers to really make the renewable energy boom happen in terms of, of our ... particularly our photovoltaic and our wind generation capability. But because of the intermittence as you've mentioned earlier on, it is that they used to be a big problem. Even in Western Australia, we see often that we might have some surplus solar to the point that it actually might even disturb the grid. So what we see therefore, with batteries, is a way to not only store energy but also to regulate the energy in the grid, which is important because anything that's like a high spike or whatever, can also create a lot of problems.

Professor Jacques Eksteen (02:27):

And so the stabilisation of that grid is a very important aspect. But also, I think the other part, what I've mentioned is - and that that relates naturally very well to the whole environmental aspect within how batteries are deployed in terms of, it's linking to the renewable devices that does not generate carbon dioxide. However, when we're talking about batteries, for instance in electric vehicles - which is probably internationally one of the bigger users of batteries - in that case we see actually a health benefit and that health benefit is related to the nitrous oxide gases that come from - and the various other gases - associated with internal combustion engines. And so air quality is a big issue and it was quite notable, for instance, with this whole COVID crisis that we're in at the moment, the COVID-19 crisis, is that if you look at the countries like China and Italy, once they went into lockdown you see this huge reduction in air pollution associated mostly with the various internal combustion engines associated with cars and buses and so on. So a huge health impact. And also worldwide, if we see the number of deaths associated with air pollution, there's that significant health aspect. So I think the two aspects therefore to deal with is health on the one hand which is with electric vehicles, and environment, which is related to renewable energy generation. And they deal with two quite separate aspects, but lead to a huge, massive uptake of batteries in the coming years. When we get down to Australia and particularly Western Australia, we see that firstly we've got all the, basically, the materials that we will require to make batteries.

Professor Jacques Eksteen (04:28):

And that would typically be things like lithium, nickel, manganese and cobalt. And also we have the, not only the, it's not only the extraction, meaning the mining of those things, but also the refining. And so we see refineries, for instance, with BHP having a a Nickel West refinery for nickel and cobalt. And companies, such as TNG and Covalent, Albemarle, all putting up plants that would manufacture lithium hydroxide, which is a refined, lithium chemical going into battery cathodes. So a lot of major industries feeding into battery materials. But also there are other types of batteries and maybe should highlight from the beginning, it's not only lithium ion batteries but also things like zinc, bromine, batteries and vanadium redox flow batteries. Vanadium redox flow battery is an aqueous battery which is also very well suited to grid applications and it's not flammable like a lithium ion battery.

Professor Jacques Eksteen (05:33):

So the nice part is having all that - all those metals that would allow us to produce batteries. But also on the other side is the deployment side. You know, Western Australia - Australia in general - but Western Australia in particular, has lots of open space. It gets a lot of wind and a lot of sun. And also we have access to do things like wave and water power as well. So various power - renewable power sources - that can feed into a grid. And lastly, it's just the application. We've got a huge number of remote, either towns or mines or resource facilities or agricultural areas which can benefit enormously by having micro grids where the micro grid would be enabled with batteries. So lot a lot of diverse applications and so we've got the benefit both on the application deployment side as well as on the, on the materials going into batteries.

David (06:41):

I guess one of the side effects of course of the COVID-19 crisis is of course that since we're all at home, if you've got solar panels, you're actually using the energy that you're generating rather than just sort of feeding it back into the grid. So we do need to consider what ... obviously CO2 emissions are very important, I guess for, as is evident to anyone who's been paying attention to the news for between three and 15 seconds. We do need to consider more than just CO2 emissions though? What are the environmental impacts of of mining materials for batteries? And how does this compare to the impact of of mining and burning fossil fuels?

Professor Jacques Eksteen (07:26):

What we've, what we've seen is a number of lifecycle assessments. So there are some well-published lifecycle assessments in the, in the literature that has made these comparisons and we see that that batteries do compare and compete very well against fossil fuels and and actually fossil fuels is a broad range of sources that would be include coal, oil and gas. So once you compare it - and each of them have got their own footprint - which would be different from one, one type fossil fuel to the next. But in batteries, what we find is that that firstly compares very well with regards to the carbon dioxide footprint right from the point of mining or extraction throughout the production up to the manufacture of the final cells and batteries. However what is important is the opportunities that we've got to also make byproducts and also repurpose a lot of the materials that are viewed as waste materials.

Professor Jacques Eksteen (08:33):

For instance, as an example in lithium refinery, typically in in hard rock that we use that come from, as an example, from Talison Lithium in Greenbushes in Western Australia, it goes into a Tianqi refinery that contains about 6% lithium, lithium oxide in the, in the spodumene, which is the mineral coming into that plant, which means that over 90% of that material is really is waste. But that waste is a, what we call an alumina silicate waste - it's a very particular type of waste - which is very useful in some in production and the manufacture of concrete. So by repurposing the waste it allows use in another industry. And also then provides, instead of material that would have been mined elsewhere, now becomes a useful raw material feeding in those industries. So that's an example for instance, of how waste can be repurposed for commercial use, leading to a far more circular economy, not only in terms of final battery recycling but actually recycling all along the way at the mining stage, when often, your mining waste is used in road aggregate and so on, up to refinery waste, which are often used in things like soil and water amelioration, concrete and cement production and so on.

Professor Jacques Eksteen (10:09):

And then subsequently, also one of the things that we, we as the CRC, or the FBICRC, are looking at, is some of the chemical waste streams as to how do we change that into a way that we can use that as fertiliser in the agricultural industry. So lots of opportunities, but even despite, you know, current opportunities, there are also - if we look at the existing waste production - it is, it is fairly ... the impact of that is fairly small compared to, for instance, if you look at coal mining and coal mining waste and then the waste associated for instance, if you're going to have a coal-based power plant and all the ash generation associated with that. So that's the solid ash. There's also the, the gasseous pollutants that you would have in like sulfur that enters the atmosphere. And then mercury and stuff like that that are typically part of coal as well. And then on top of that, you've got your carbon dioxide. So, so even with coal mining and coal burning, there's a far broader range of pollutants than only the carbon dioxide that has to be dealt with. In the case of batteries, though, we've got a lot of opportunities to repurpose these materials for commercial use and have a true circular economy around most materials going into batteries.

David (11:37):

We've all heard about lithium ion batteries. I mean pretty much everyone has a device which uses them. My phone does, my laptop does, and I'm using both of them right now. But obviously they're not the only technology that exists. Could you tell us about hydrogen fuel cells and what benefits they offer?

Dr Terry Humphries (11:58):

Yeah, so hydrogen fuel cells are basically electrochemical devices that can turn hydrogen gas into electricity. So basically the hydrate goes into the anode and produces electrons. And the only byproduct from this, apart from the electricity, is water and heat. So if we're going to use these fuel cells in cars, for instance we're not releasing any carbon dioxide or NOx gases or anything like that, plus these fuel cells have a greater efficiency than you'll get from the petrol cars. Up to the order of two to three times the efficiency. So these fuel cells have already been implemented into a number of cars throughout the years. And as of 2018, there was three models available: the Toyota Mirai, the Hyundai Nexo and the Honda Clarity. And so these fuel cells have been implemented all over the world as well, not just in cars but trucks, forklifts, there's hydrogen bikes, hydrogen boats, you name it, it's happening. And also the military are starting to use hydrogen fuel cells as well. Just because of their lightweight nature and the fact that they're so scalable. You can build them from just mobile applications all the way up to large scale energy storage as well and energy production. And so that's the main benefits of them, whether it be the clean emissions, the scalability, and also the efficiency compared to fossil fossil fuels.

David (13:44):

No energy source or indeed no technology is without its critics. Part of the argument against ... part of the argument is that that hydrogen energy storage is commonly produced using fossil fuels. Does this present a problem?

Dr Terry Humphries (14:04):

Yeah. Well that is true. I mean, as of 2015, 95% of the global hydrogen production was using fossil fuels, using thermolysis or steam methane reformation. But in recent years, this landscape is dramatically changing. And that's because of the amount of renewable energies coming to play, whether it be solar, wind. I mean here in Perth, there's actually so much energy being produced with solar that it's overloading the grid. So we actually need a way to take some of this electricity off the grid as well. And this can actually be stored as hydrogen. So we would take the excess electricity and we can pass this through an electrolyser, which is basically conducting electrolysis of water and this produces hydrogen, which can either be compressed and stored or used directly in industry. And so the more and more these electrolysers are being introduced into the landscape, they're becoming cheaper, they're getting more scalable. And so that means vast quantities of hydrogen can be produced. And so with this increase in hydrogen production, the cost will be brought down somatically too. So once hydrogen is cheaper to produce and use than fossil fuels, then it'd be more popular to make hydrogen using green electricity rather than fossil fuels.

Professor Jacques Eksteen (15:36):

Terry, if I can maybe add to that. I think one of the things that even with hydrogen from let's say natural gas, the opportunity ... one of the big challenges with hydrogen has been in transport and storage. And by solving, even if we solve those issues and we, and we get well commercialised for applications coming from natural gas and basically piggybacking on a fairly large industry, because this is the key thing, is that often when you want to drive into, when you want to drive a new industry like a hydrogen industry, you have to have a, it's often useful to have a supporting industry. And the gas industry is a large industry that can help to get this thing going and particularly with regards to storage and transport.

Professor Jacques Eksteen (16:27):

And one of the big opportunities is also then transporting this - like we're doing with liquified natural gas - we can also do with hydrogen to transport it into Asian countries where a lot of these Asian countries don't have good quality renewables. So, so for instance, if you're Japan, for instance, you firstly it's a mountainous country where they don't have good quality sunshine across the year, they don't have good quality wind as well, so sustained wind. They don't have huge tidal sources. And so they're quite stuck in terms of their options to generate renewables. So for them, it's there for an option to draw, to basically import, hydrogen from countries such as Australia that firstly can develop it off the back of a national gas industry. And then as the technology progresses, feed in the green hydrogen from the electrolysers into the system. So there's a, there's a sequencing or staging here in terms of economics that's important. And we, we can then facilitate the transition into a hydrogen economy for players to the north of us, the countries to the north of us, which renewable generation using conventional means would be far harder and more difficult to do than for us. So it's - the other thing I think about hydrogen, which is important compared to batteries for instance, is when we're looking at the duration of the type of time that we want to bridge. So for instance, batteries are very good for the shorter time periods, let's say up to - anything up to eight to 12 hours, but not really more than that. Whereas hydrogen allows us to spend months and even seasons. So that, to take out some of the seasonality that we see as well, hydrogen is that buffer that allows us to basically smooth out the fix in, in, in energy across seasons and weeks and months, which is something that batteries can really do that well.

Dr Terry Humphries (18:41):

You're quite correct there. I mean every ... as we go forward, I think that every industry is going to pay an important part. We have to put all of these resources into use together if we're going to make the most of sustainability. I mean, yeah, batteries, fantastic for short term grid usage. We definitely need to be exporting hydrogen as well. And as you mentioned, it's a fantastic opportunity for Australia to start exporting hydrogen. But first of all, yes, we might need to use fossil fuels to produce hydrogen. Predominantly but there's plenty of projects that are going on to use green electricity to produce hydrogen and send this over to Japan and Korea, et cetera. I mean luckily enough at Curtin University we've got a major project going on to be able to use solid state hydrogen storage and to be able to send this off where we'd hopefully mine the raw materials in Australia, send that to Japan, extract the hydrogen from there. Then we would send that back to Australia where we could then recycle that material as well. So there's a number of projects going on and definitely everything needs to be used in tandem if we're going to make the most of it.

Professor Jacques Eksteen (20:11):

Sorry. So the hydrogen economy, we should, we should then, like with batteries, you've got, you know, fairly complex supply or value chains and so on. But hydrogen also has got a, in a sense, a bit of a complex value chain. In the sense you've got the generation aspect of it. You've got the compression aspect or the, you've got the generation, the purification and you've got the compression and storage. And as Terry mentioned, there are a range of storage methods: solid state or maybe in the form of liquified ammonia, or as compressed hydrogen itself. So each have their own benefits from environmental safety and an energy efficiency perspective. But once you store it, then there's the transport, it's the materials construction around these things. And then when we then deploy that in hydrogen's case, it's deploying that through, for instance you know, the fuel cell technologies, which are, which as Terry mentioned, is highly efficient. But I think similarly, batteries have got this fairly complex value chain and all the links in this chain have to work together for it to be an effective alternative economy. You know, at the global scale.

Dr Terry Humphries (21:34):

Yes, I feel that the transport of hydrogen globally is an issue. And especially even within countries in America they've shown that you can use like existing pipelines from gas and to transport the hydrogen as well. Other than that we're faced with having to use trucks to move the hydrogen. So there's a large initiative as well to make a hydrogen highway throughout WA where trucks will be able to refuel at stations and refuel the stations as well. And these stations will also be producing hydrogen on-site from renewable energy sources. So yes, definitely making a network for these materials is definitely important.

David (22:22):

Fossil fuels are still a very lucrative industry. In fact, well, I think that's probably a bit of an understatement. Much of our economy is dependent upon fossil fuels. Meaning there's going to be, it's going to be quite a bit of institutional resistance to moving away from them, isn't there?

Professor Jacques Eksteen (22:43):

Yeah, I would, they would be. I mean, the one thing is that one after realize that the, if you look at there are there are two sides to that. One is the internal energy usage in Australia, but the big, the big aspect really is the export side as the exporter of liquified natural gas and the export of coal. And we can't just switch that off with a flick and then think that, you know, it's not going to have a huge economic impact on the country. So it's a matter of a gradual transition. The other thing is that we must look at alternative usage, for instance, for natural gas. So in the case of natural gas we can produce olefins. So so that's from methane, which is natural gas. You can produce something like ethylene, and which is the, basically the, the building block of your organic chemistry. All the petrochemicals that you can make from that, including, you know, food acids, amino acids that all the parts of the building blocks of proteins and so on and various other chemicals. And which would lead to a value add. And I think that's very important if we can go from, let's say natural gas to olefins and hydrogen because you can actually produce hydrogen and other funds by stripping the hydrogen off the methane and you get ethylene gas or, or various olefins from that. And so that's one big opportunity to say, well, instead of necessarily just exporting to burn it, because we actually then taking it to a very poor end product, we can actually add value to our our some of these fossil fuel sources, particularly natural gas. Coal maybe is a bit more difficult.

Professor Jacques Eksteen (24:31):

If you look at, for instance in South Africa, they, you've got a company like Sasol which manufactures petrochemicals from coal. It is a far more expensive process to do that, but it's still doable. And I think the important message that I'm trying to get across is that we can add value to fossil fuel sources instead of burning them to a very poor quality end product, which is just carbon dioxide. And that's the long game that we should be in that in the end. That said, it's not as, as I say, it's not a matter of just flicking a switch and we go from, from you know, an economy which has got strong support by fossil fuels to an economy which does not have that part in it because the impact that it would have on taxes, the impact that it would have an employment, on the balance of payments in the country and so on would be enormous if it's done too rapidly. And therefore a staged approach would then be more sensible.

Dr Terry Humphries (25:36):

Yes, that's quite correct. I mean, you can't go flicking a switch and there's no discounting that we need the revenue from fossil fuels and all these industries. So for jobs and taxes, but at the same time there has to be a transition. All of these companies recognise that too. And it's the case of all of these materials, as you said, can be value added rather than just burning them. But it's a case of preserving them for the future. It's not just finding an alternative use for them. It's keeping them for the future so that we don't run out of them in the next a hundred, 200, whatever number of years.

Professor Jacques Eksteen (26:22):

Yes, I agree. I mean, this is the key thing of you know - they're all finite resources - and they, it's not really recyclable in the conventional sense, at least the fossil fuels aren't. You know, while batteries can be recycled as an example, you know, when you're burning coal or natural gas, you basically get into, into a product which is not really in a recyclable, you know, recyclable in the conventional sense. So ... and you can try and sequester for instance some of the carbon dioxide, but you're converting into a fairly useless product in the end.

Dr Terry Humphries (27:02):

Yes. Quite correct. Yeah. Yes, sequestering is a a great idea. But end of the day, there's only certain amounts or places that we can actually sequester this carbon dioxide to. So yeah, definitely substitute rather than sweeping under the carpet, is definitely in accord.

David (27:26):

Well more likely underground than sort of the, well, the carpet that we call the ground, I guess. There's an Australian startup which has launched a zinc bromine gel battery. Do you think that could be another player?

Professor Jacques Eksteen (27:44):

Yeah, so maybe we should probably ... there are a range of batteries. And so I think the one thing that we should put aside first is that you've got lithium ion batteries and also solid state lithium batteries. But then we've got companies such as Redflow, which is a zinc bromine, battery. You've got as I've mentioned, vanadium redox flow batteries, which originally was patented in Australia that comes from the University of New South Wales and subsequently a lot of research internationally. And that's an aqueous system using various vanadium salts or ... but there are also some simple batteries like even salt water batteries. So it's often a question rather of fit-for-purpose batteries. So there are different batteries for different types of applications and depending on your power requirements and your storage requirements per unit mass and per unit volume, the longevity of the battery that you would like and the life that you want to get out of that battery, for instance. The things like, you know, can you, does it need to be non-flammable or not? Is that a big issue or not? Are there any gases generated during, during the operation of the battery or not? And so all these things would then determine how it's used, for instance, in a stationary type of storage for, let's say, grid storage and micro grid storage versus electric cars versus batteries for submarines or in aerospace or in agriculture or in buildings. And so there are different needs. I mean, one other area, which is a huge opportunity, is in, back into mining. And for instance, mining or remote operations. It runs underground lines and it's, and it comes with its own particular challenges to do things at the underground level. And so this whole aspect of fit-for-purpose batteries is important.

Professor Jacques Eksteen (29:54):

And so instead of, you know, having a one size fits all type of approach the battery space is you know, got this very particular aspect of having appropriate batteries for specific needs rather than, you know, a general, general approach, a general battery. And so lithium ion batteries even lithium ion batteries are broad range of batteries types that you'll find under lithium ion batteries. And selecting the right battery is very important. And that's hopefully one of the things where the Future Battery Industry CRC can support players in this space, because it seems to be sometimes a challenge to select the appropriate battery for the right application and to design the battery system. I should also add, maybe, when we talk about battery versus cell, so typically you would have a single unit which is a cell. But a battery is typically, a you know, it can be hundreds of thousands of cells that are combined into a module or a pack. And on top of that, there's what we call a battery management system, which controls it's, you know, overcharging, over discharging, keeps the battery safe and cool, that it doesn't overheat. And so a battery pack has got far more to it than the individual cells, you know. So and again, we have to choose the correct cell chemistry on the one hand and then subsequent to that, the correct design for going towards battery packs and the control systems that sit on top of it.

Dr Terry Humphries (31:43):

Yeah. Whilst lithium ion batteries are fantastic for multiple applications, as I mentioned before, we have to use everything in tandem. So whilst there's these different batteries being produced, like the zinc bromine batteries and zinc vanadium batteries, it's good to be able to use different resources from the globe. And so all of these don't become a finite resource as well. Although in some regards they are. But yes, there's so many different types of batteries out there. For a larger scale battery there's even thermal batteries that we can use as well. These can even use hydrogen and carbon dioxide as their fuel as well. And it just takes the heat and then you can use that heat to drive a turbine later on. And you can use renewable energies and store and produce this heat as well. So there's a number of different ways that we can power the globe. And you know, this startup company you mentioned, I think, Redflow, yes. I mean there's multitudes of these companies coming out in Australia and you know, it's a very innovative nation. And so I do feel that Australia can come off the bigger powerhouses in the world.

David (33:08):

Well that's very encouraging. Well it's good to know that we're coming up with some with some useful stuff. One final question before we go and I warn you, this might reveal when we researched the brief for this particular episode - because of course this is back before, back when we were also innocent a few months ago before the world started ending. If you, you might remember the, the Cyber Truck that Elon Musk unveiled a couple of months ago. Yes or no? What do you reckon?

Dr Terry Humphries (33:45):

Well, yeah, it definitely seems a beast of a vehicle. I mean, what is it, the most high performance version apparently is going to reach 100 km/h under three seconds. I mean, that's pretty good going, especially using battery technology.

David (34:06):

Mmm. Jacques?

Professor Jacques Eksteen (34:07):

Yeah, it's, well, it's I think it's for different tastes. I mean, in terms of shape, you know, I guess I would prefer less of a cyberpunk shape. But I mean, in terms of it's capability, it's absolutely, you know, fantastic. So I mean I think it's hot, but I think also, you know, there's probably a specific demographic that would prefer that. And particular, you know, I think a lot of the millennials are probably far more aligned to them than maybe the baby boomers. But I think that's an age thing more than anything else. I'm a Gen-Xer so I'm actually the same age as Elon Musk and and yeah, it's fascinating but I'm not sure I'd necessarily buy one for myself.

Dr Terry Humphries (35:10):

Yeah, well they've definitely got a decent price tag on them. So apparently, I mean you can buy one well in 2021 apparently for about 60,000 American dollars. So that's not too bad going, I'd say, for new technology.

David (35:25):

Well that, that translates to about seven, sorry, about 98,000 Australian dollars. Although bearing in mind, bearing in mind our dollar isn't very good right now, so might not be a great comparison.

Professor Jacques Eksteen (35:36):

I think the important thing with, like most technologies, is how, you know, over time, how the price would come down. So as soon as you get into mass production, you get into the typical lower cost of production over time. And as more competition enters that space, you'll see prices drop. So initially you will typically find with - as it was with batteries themselves and with renewables as well - they started off expensive and they, and then, you know, there was the typical reduction that you saw over time. So a lot of the new technologies typically you would expect to be expensive at the start and the same would be even with hydrogen and so on. A lot of these things go down a learning curve and as you go down the learning curve, you actually get significant efficiencies that you, that you unlock and prices would tend to go down.

David (36:32):

Well as, as a representative of, oh wait I'm not a millennial actually, I think I'm a gen Z-er actually - as a 22 year old, not, not really my style. I'll, I'll probably be waiting for the for the price drop before I spring for an electric car. I think I'm quite happy with my Commodore right now, but I probably should, I probably should switch to something that's perhaps a little bit better for the environment. Jacques and Terry, thank you very much for joining me and thanks for sharing your time to ... well, usually we'd say thanks for coming in, but thanks for staying at home.

Dr Terry Humphries (37:11):

Yeah. Thank you very much

David (37:13):

And thank you for listening. You've been listening to The Future Of, a podcast powered by Curtin University. If you have any questions about anything we've raised today, then please feel free to get in touch by following the links in the show notes. Bye for now.