Grid Think

I have written about the economics before, $4/lb or $9/kg of Chinese Vanadium Pentoxide makes $70/kWh in just the electrolyte cost of the Vanadium Flow batteries, this cost excludes converting the ore into battery grade electrolyte, tanks, pumps, pipes and cell stack (which adds up  quickly by the way), the total cost of the system can sit well above $200/kWh depending on the specs of the battery. Now if you want an LFP battery, its landed cost would be around $120/kWh. That's a 40% discount !! So the obvious question arises, who buys such an expensive battery ? And how does it make any financial sense to buy a VFB ? If you consider the upfront cost of VFBs they can never be competitive- You can say that LFP degrades and VFB doesn't, so over a long period of time, VFB would be cheaper, but VFB takes a lot more space, and that cost has to be accounted for, I have run some financial models but VFBs can never be competitive with LFPs, let alone much cheaper Sodium Ion batteries ab...

So I have decided to embrace the fact that Fe-Cr batteries operate at a fundamentally higher temperature. But now you'll say it makes no sense to heat the battery, the costs alone would bankrupt me.  Let's take a sample system of 1 MW / 10 MWh,  If we assume a conservative energy density of 10 Wh/L, Volume of electrolyte (L) = Total energy required  / Energy density  Volume =  10,000,000Wh / 10 Wh/L  =1,000,000 L  We would need 1 million liters of electrolyte and calculate the mass of water as by keeping density as 1 kg/L.  mass (kg) = volume  x density of water  m = 1,000,000 L x 1 kg/L = 1,000,000 kg  If I take the conservative specific heat of water as 4,187 J/kg·K, s tart with an ambient temperature of 20°C and keep my ΔT as 20°C,  Q (heat energy) = m x c x ΔT   m = mass of water = 1,000,000 kg , c = specific heat capacity of water = 4,187 J/(kg·K)  ΔT = temperature change = 40°C - 20°C = 20 K   Q =...

Nafion and FumaSep, both membranes are pretty expensive for me, and if they are expensive for me I don't think they would be any cheaper for any Flow Battery manufacturer. Because its basic economics, if your raw materials are expensive your end product can't be cheap. So most flow battery manufacturers don't really bother with inventing new membranes, they use a material called DARAMIC separator, it is made up of Polypropylene (PP) or Polyethylene (PE) sheets with micro level holes in them, nothing new, its a 50 year old separator material which is used to separate positive and negative side. Daramic is used in literally all batteries, you name it, Lithium Ion, Sodium Ion, Lead Acid , All- Iron Hybrid Batteries and yes even Vanadium Redox Flow Batteries.  Source There has been substantial amount of research on cheap membranes, but most of them last only a few weeks and the membranes that actually last.... well they are Nafion and Fumasep. But Daramic works in a fundamental...

 I'll be honest, I didn't dream of Iron Chromium Redox flow battery in my dreams, nor did I have any secret information from NASA. I did what any other 22 year old would, ask Gemini about it. If you ask Gemini or ChatGPT about VRFBs, there are high chances that it will suggest alternate chemistries also. Now that can be a good thing or a bad thing. If you know a little bit electrochemistry, it would spit out a very obvious answer. If you don't, you'll go down the same rabbit hole I did. AI doesn't know your intentions. So it acts as the most efficient information summarizer, and that's great, if you just want information, not if you want action. So one of the first alternatives to VRFBs Gemini suggested was Iron - Chromium, and it made a lot of sense because Iron and Chromium are commodity metals, Iron is literally the most mined metal on earth and chromium comes third [ source ]. Their commodity prices are - Iron - $110 per ton   (at the time of writing) Chromi...

After reading the Vanadium post, I am sure its pretty clear that VRFBs are expensive but they are one of the oldest, most stable, most deployed and proven redox flow battery chemistry yet. So, I feel its worth giving Vanadium another chance before dismissing it fully. Vanadium Supply Chain As of 2026, global Vanadium production is 100,000 metric tons, that may sound like a lot, but its tiny, to put that in perspective, we produce 3x more Lithium and we still need to discover and open new lithium mines, and Lithium supply chains are considered to be volatile.  Since we are talking about supply chain, its obvious to see when you buy Lithium or Vanadium ores, where exactly are they being dug up. Lithium producing countries- Source Vanadium producing countries - Source I'll be honest even I am a little surprised, I imagined Lithium to be produced in China, and its an obvious assumption, if the biggest lithium ion battery makers are Chinese, it would be obvious to think that its produce...