TL:DR – Vanadium Redox Flow Batteries (VRFBs), or also known as vanadium flow batteries, are a type of rechargeable flow battery that uses vanadium ions in different oxidation states to store and deliver energy, offering advantages like long lifespan, scalability, and safety

Mat Ferrell made an interesting YouTube video regarding VRFBs that provides a good overview of this growing technology. Storing Energy is a crucial part of the Energy cycle and this is promising technology.

Here is the transcript.

tactiq.io free youtube transcript

Why Isn’t This Revolutionary Battery Everywhere?

https://www.youtube.com/watch/3_NCnxO1KLY

00:00:00.400 Vanadium redox flow batteries are hitting the bigtime, and I mean big. One of the biggest  
00:00:05.080 Battery Energy Storage Systems (BESSs) ever is a vanadium redox flow battery that just  
00:00:08.920 came online in China, with an even bigger one to come in Switzerland. And there’s  
00:00:13.040 even more on the way in other countries too. But it raises a couple of questions:  
00:00:16.960 “why now,” and “why are they suddenly catching on everywhere else but North America?”
00:00:21.400 I’m Matt Ferrell … welcome to Undecided.This video is brought to you by Ground News.
00:00:28.880 This is a vanadium redox flow battery (VRFB). They play nice with solar and this one can fit  
00:00:34.040 in your garage … and I wish I had one in mine. Flow batteries scale-up really well too. This one  
00:00:39.960 here is a 51 megawatt facility in Hokkaido, Japan, and it was the biggest in the world  
00:00:44.360 when it opened in 2022. However, at the end of 2024 it has been dwarfed by Rongke Power’s own  
00:00:49.560 Xinhua Ushi Energy Storage Project in Xinjiang, northwest China. At 175 megawatts (MW) and 700  
00:00:56.200 megawatt-hours (MWh) of storage, it’s currently the largest battery storage system of its kind.
00:01:00.680 But soon, an even bigger VRFB will be online. Rongke’s monster is set to be overshadowed  
00:01:05.200 by a VRFB starting construction this year in Switzerland. Part of a massive telecom facility,  
00:01:10.680 this VRFB clocks in at 500 MW and 1.2 gigawatt-hours of storage. This is a  
00:01:16.280 pretty meteoric rise for vanadium battery tech. So how does it work? Where did this tech come  
00:01:20.480 from? And maybe most importantly, why has it exploded in popularity the last few years?
00:01:27.520 Broadly speaking, redox flow batteries work by having two large tanks,  
00:01:30.880 one with a positively charged electrolyte solution and one with a negatively charged  
00:01:34.240 solution. Both these tanks are connected to a central chamber or “stack,” and when we  
00:01:38.760 pump our electrolyte solution through the stack, we get an ion exchange,  
00:01:41.880 or redox effect as one side reduces and the other oxidizes. When charging,  
00:01:46.640 we put electricity into the battery and this causes ions to move from the positive side of the  
00:01:50.480 membrane to the negative side. The redox process is reversible, so the stored energy is released  
00:01:55.680 as ions and electrons return to their original states, generating a usable electric current.
00:02:00.720 Vanadium wasn’t the OG flow battery, though. That honor goes to the zinc flow battery,  
00:02:05.200 patented all the way back in 1879. I’ve got a video on that if you’re interested. Not a whole  
00:02:10.199 lot was done with it until the energy crisis saw a surge of interest in renewables and alternative  
00:02:14.240 battery technologies. NASA experimented with redox flow batteries in general,  
00:02:17.960 but its efforts weren’t very successful. Others weren’t having much luck either,  
00:02:21.560 because we just didn’t have good enough membrane tech or electrolyte solutions.
00:02:25.560 Then, in the 1980s, researchers at the University of New South Wales (UNSW) in  
00:02:28.960 Australia successfully demonstrated vanadium redox flow chemistry using vanadium dissolved  
00:02:33.880 in sulfuric acid. And just like that, we had a promising electrolyte. There was another  
00:02:38.320 boom of interest, and the university patented the tech and licensed it to a few companies.
00:02:42.960 What makes vanadium interesting? It’s a bit of a weirdo, kind of like me. It likes to both give  
00:02:48.160 and receive ions, giving multiple charge or oxidation states. In fact, vanadium batteries  
00:02:52.800 rely on vanadium having not one, not two, but four different possible charge or oxidation  
00:02:57.840 states. Two of them are more positive, and two of them are more negative. Chemically,  
00:03:02.280 this is very strange, and means that we can use vanadium for both the positive  
00:03:05.960 and negative sides of the flow battery. Most flow batteries require two distinct solutions,  
00:03:10.920 which can result in them bleeding over the membrane and hampering the battery’s  
00:03:13.960 efficiency and lifespan. Vanadium doesn’t have to worry about that. I also imagine it  
00:03:17.920 makes the supply chain a little easier if you have to source one less electrolyte solution.
00:03:21.920 Still, these batteries remained pretty niche and underutilized for several years. But 2006  
00:03:27.013 would see several VRFB patents expire, and plenty of organizations spent serious time  
00:03:31.800 and money developing VRFBs. That same year, the U.S. Department of Energy’s Pacific  
00:03:36.400 Northwest National Laboratory started R&D on their VRFB formula. By 2012,  
00:03:41.840 this led to a new-and-improved vanadium-based electrolyte formulation that was twice as powerful  
00:03:46.080 as similar mixtures. Soon, VRFB technology made its way from the lab to real life,  
00:03:51.360 aided by the growth of solar and wind power. Adoption was slow initially, but  
00:03:55.120 with companies like Rongke Power announcing some big plans for the technology, the race was on.
00:04:00.120 So what has Rongke Power done with VRFBs? As I mentioned earlier…a lot. At 175 MW and 700 MWh,  
00:04:07.360 the company’s facility is the biggest VRFB on the planet, which also makes it the biggest  
00:04:11.680 flow battery on the planet. That’s at least until that Swiss facility begins construction this year,  
00:04:16.720 but I’ll get to that in a moment. This isn’t Rongke Power’s only big VRFB. The  
00:04:21.160 company is behind another, smaller but still huge 100MW/400MWh Dalian system. Back in June 2024,  
00:04:29.840 Rongke reported that the Dalian facility completed the world’s first black start  
00:04:33.880 test of a large-scale thermal power system. A “black start” involves restoring power to  
00:04:38.760 the grid following a total blackout. It’s an important safety measure that  
00:04:42.560 demonstrates that the VRFB can provide enough energy even when total disaster strikes.
00:04:47.760 Why is China investing so much in giant VRFBs? Well,  
00:04:50.800 as Uncle Ben once said, with green power comes green responsibility…and  
00:04:55.080 that responsibility is storage. China aims to be the world leader in renewable energy.
00:04:59.320 But as you dive into topics like renewable energy and new technologies, it’s important to have  
00:05:03.320 diverse and credible sources of information. My team and I always strive to find the best sources,  
00:05:08.000 but misinformation and bias exist in all reporting—which is why I’m excited to have  
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00:06:26.520 and I think you’ll find Ground News just as valuable as I do. Thanks to Ground News and all  
00:06:30.960 of you for supporting the channel. Now, back to why China is investing so much into giant VRFBs.
00:06:36.040 Part of this drive means constructing massive energy storage facilities to work in tandem  
00:06:40.160 with massive renewable energy generators. As we’ve discussed in previous videos,  
00:06:44.400 a lot of emissions-free power has the downside of being intermittent.  
00:06:47.680 The sun isn’t always shining, the wind isn’t always blowing, y’know the deal.
00:06:51.960 Before Rongke Power, the biggest VRFB could be found in Japan’s Hokkaido region. Hokkaido  
00:06:56.800 gets a ton of wind, so naturally the Hokkaido Electric Power Network (HEPCO) has invested in  
00:07:00.960 a robust wind turbine system. But they wondered what was the best way to store all that wind power  
00:07:05.720 for later? Ultimately, it settled on Sumitomo Electric Industries and a massive VRFB system.
00:07:11.200 At 51 MW, this setup uses 130, 10,000-gallon,  
00:07:15.240 vanadium redox tanks. That’s more than enough VRFBs to power 27,000 Japanese homes for four  
00:07:20.960 hours. That’s about what you’re going to get from grid-scale lithium energy storage systems,  
00:07:25.640 though Sumitomo Electric says it expects future projects will aim to double that duration  
00:07:29.680 to eight to 10 hours. That would be a big deal, as that’s what you’d need to cover  
00:07:33.600 for solar panels during the night or to give wind turbines a lot of wiggle room between  
00:07:37.760 gusts. The project has been so successful that Sumitomo has gone on to install similar VRFBs  
00:07:43.000 systems all over the world, including in Belgium, Australia and even California.
00:07:48.320 So, let’s talk about the soon-to-be biggest VRFB facility. Swiss telecommunications  
00:07:52.240 company FlexBase is building a 20,000 square meter data center in Laufenburg,  
00:07:56.480 Switzerland. Data centers take a lot of energy, so FlexBase wants to offset that  
00:08:00.960 with tons of green energy and green energy storage. To that end, the company is set to  
00:08:05.080 begin construction on a 500 MW/1.2GWh VRFB, the biggest in the world. The campus will  
00:08:12.960 generate at least some of its own power with a 8,400 square meter solar panel system. FlexBase  
00:08:17.920 is also planning to use its waste heat as part of the Laufenberg’s district heating network.
00:08:22.440 Laufenberg was chosen as the home for this facility for a reason. The town is right across  
00:08:26.560 the Rhine river from Germany, and also sits near the original connection point for the electricity  
00:08:30.800 grids of France, Germany, and Switzerland. This network node was decommissioned in 1958, but the  
00:08:36.640 location is still critical for the distribution of green electricity in Europe’s interconnected grid.
00:08:41.480 But, as promising as they may be, flow batteries are just as vulnerable to economics as any other  
00:08:45.880 new technology. Back in March 2024, Horizon also announced it was preparing to test Redflow’s  
00:08:51.400 zinc-bromide flow battery, but the project didn’t make it very far. By October 2024,  
00:08:56.240 Redflow went belly-up. It’s a painful example of how precarious the greentech business can be.
00:09:03.600 Clearly, VRFB tech works great for gridscale storage, but why? We’ve covered this previously  
00:09:09.080 so I’ll keep it brief. Flow batteries are great at large scale projects primarily because  
00:09:13.720 they’re so easy to scale up. Need more juice? Get bigger tanks. You might be sitting there saying  
00:09:19.720 “no duh,” but stuff in the electro-chemical world is rarely that simple. Look at some of  
00:09:24.200 the other emerging battery technologies, and the simplicity of scaling up a VRFB seems almost too  
00:09:29.480 good to be true. If you want to adjust the capacity of most other battery systems,  
00:09:33.160 lithium included, you’re just buying additional batteries. You want to double the capacity,  
00:09:37.520 you have to double the number of battery packs. Power output and energy storage scale together.  
00:09:42.960 VRFBs can scale those separately between the tanks (the storage) and the stack (the power).
00:09:48.960 VRFBs, of course, have their own perks aside from being flow batteries. We’ve  
00:09:52.680 already mentioned that vanadium is a strange substance with four different oxidation states,  
00:09:56.720 which makes it really convenient and efficient in a redox battery. That’s the big one, but there’s  
00:10:01.320 other benefits, too. The electrolyte solution isn’t flammable, and isn’t sensitive to extreme  
00:10:05.760 temperature fluctuations. That kind of safety is important, especially for wildfire-prone regions.
00:10:10.960 Another small but useful perk is that VRFBs can stay discharged for as long as you need them to  
00:10:15.720 be without degrading. Their simple chemical formulas and benign chemical reactions give  
00:10:20.240 them extremely long lifespans. We’re talking upwards of 15,000-20,000 cycles. By some accounts,  
00:10:26.160 that’s five times longer than lithium. Sumito claims that its VRFB will last at least 20 years.
00:10:31.440 That all helps to contribute to their low LCOE, or Levelized Cost of Energy. Generally,  
00:10:35.760 VRFBs are going to have cheaper LCOEs than lithium systems. When a VRFB does finally kick the bucket,  
00:10:41.120 most of the vanadium can be recycled into a new VRFB. US Vanadium demonstrated its  
00:10:45.640 ability to recycle 97% of the electrolyte from a decommissioned VRFB. Sumitomo took  
00:10:51.000 spent VRFB electrolyte from a battery that was in service for a decade, then processed it and  
00:10:55.760 repurposed it for use in a different VRFB. The company says it’s been working effectively in  
00:11:00.040 its new home since 2012. To be fair, these examples are isolated showcases, far from a  
00:11:05.480 fully functional VRFB recycling system, but they do highlight the recycling potential of vanadium.
00:11:12.960 Of course, vanadium batteries aren’t without their drawbacks. Let’s just get the most obvious one out  
00:11:17.400 of the way first: They’re big. That’s great for grid scale storage, a potential option  
00:11:22.680 for residential storage, but not something you’re not gonna see inside an EV or laptop.
00:11:28.800 VRFBs also have a relatively poor round-trip efficiency (RTE). That’s a measure of how much  
00:11:33.920 electricity you can store in a battery and then actually pull out later. When  
00:11:37.560 VRFB cells are small, they have a pretty good RTE of 85–90%. But once you get into  
00:11:43.440 kilowatt-scale stuff that number drops to 57–75%, due to hydraulic losses and shunt  
00:11:49.600 currents. Not ideal for a technology that we want to use in massive energy storage systems.
00:11:54.520 As for the question of why we aren’t seeing a lot of vanadium batteries here in the US,  
00:11:58.680 vanadium has a serious supply chain bottleneck. 75% of the global vanadium supplies comes to us  
00:12:04.240 as a byproduct from just 10 steel mills in China and Russia. Other countries like  
00:12:09.520 the United States and Australia produce some vanadium, but not enough. Vanadium is often  
00:12:13.920 found in iron ores used in steelmaking. With steel being easily recyclable,  
00:12:18.040 little vanadium is produced in the US. If we want to build massive VRFB facilities, like the kind  
00:12:23.000 we’ve been talking about today, we may need to alternate sources of vanadium. Then again,  
00:12:27.080 there are some significant vanadium deposits in the United States that are largely untapped.
00:12:31.880 This plays into another VRFB issue: upfront cost. Vanadium is twice as expensive as lithium. That  
00:12:38.000 can be offset by their long lifespan and their low cost of maintenance. However,  
00:12:41.840 the high initial cost and their new-ness on the market make VRFBs an expensive risk to a  
00:12:46.920 lot of investors. And again, massive facilities will take massive amounts  
00:12:50.400 of vanadium. Anyone out there willing to offer a Costco-style bulk discount?
00:12:54.920 These are some of the reasons why, despite vanadium’s strengths, you might choose other  
00:12:58.280 flow battery chemistries, like zinc-bromide or hydrogen-bromine. If vanadium is the problem then  
00:13:03.520 just ditch vanadium, right? Of course, these batteries have their own issues,  
00:13:08.040 but that’s a topic for another video. Like maybe this one here.
00:13:12.120 Where does that leave VRFBs on the technological readiness level? A high score for sure,  
00:13:16.320 maybe as far as a 9. They’re out there and working right now, providing hundreds of  
00:13:20.720 megawatts to people across the globe. It’s proven technology with a well-defined niche.
00:13:25.600 As we continue to decarbonize, it’s possible that VRFBs will become more popular.  
00:13:29.720 It’s pretty heartening to see some of the massive facilities already working,  
00:13:32.680 and even bigger ones are on the way. Still, I want to caution against unbridled optimism. Despite the  
00:13:37.840 successes of VRFBs in China and Japan, there’s no guarantee that all these announced, new facilities  
00:13:43.080 will complete construction. Still, these early, full-scale successes are pretty exciting.
00:13:48.400 But what do you think? Do you think we’ll see more of these in the US and elsewhere?  
00:13:51.880 Jump into the comments and let me know what you think and be sure to listen to my follow  
00:13:54.890 up podcast Still TBD where we’ll keep this conversation going. Thanks as always to my  
00:13:58.760 patrons for your continued support and helping to keep the channel going. Keep your mind open,  
00:14:02.960 stay curious, and I’ll see you in the next one.