FREMONT, CA: The efforts to lift power generation and electrical grid into the 21st century are complex. It requires a new generation mix of low-carbon sources that comprise hydro, renewables and nuclear, ways to gather carbon that don’t cost a zillion dollars and make the grid smart. But battery and storage technologies have had a challenging time keeping up. And they are vital for any success in a carbon-constrained world that leverages intermittent sources like solar and wind or that worries about resilience in the face of natural disasters and harmful attempts at sabotage.
Battery technologies do keep getting improved. Recently, researchers have come out with a new fast-charging battery technology leveraging that uses a glass electrode instead of a liquid one, sodium instead of lithium, and may have three times as much energy density as lithium-ion batteries. Besides batteries, people do have other technologies for storing intermittent energy, like thermal energy storage, which enables cooling to be created at night and stored for use the next day during peak times.
At present, the most extensively used storage method is pumped hydro storage, which leverages surplus electricity to pump water up to a reservoir behind a dam. Later, when power demand is high, the stored water is released through turbines in the dam to create electricity. Pumped hydro is used in 99 percent of grid storage today, but there are geologic and environmental constraints on where pumped hydro can be implemented. But people require utility-scale chemical battery storage to manage with quick intermittency in both generation and demand. These require to be very large but very stable and long-lasting.
The latest technology to emerge is the vanadium redox battery. V-flow batteries are fully containerized, compact, nonflammable, reusable over semi-infinite cycles, discharge 100 percent of the stored energy and do not degrade for more than 20 years. The Earth’s crust has more vanadium than lithium, and the companies produce twice as much V as Li each year. Most batteries leverage two chemicals that change valence in response to electron flow that converts chemical power to electrical energy. V-flow batteries use several valence states of just vanadium to store and release charges in a water-based electrolyte containing vanadium salts.
