Redox Flow batteries are actually shipping today.<p>And it has nothing to do with &quot;better&quot;. Lithium Ion has more energy per watt, but Redox Flow is just so much cheaper and also has a 20+ year life expectancy. It will be very hard for Tesla to compete when they&#x27;re making car batteries and trying to apply it to utility scale.<p>Who cares about energy density when you&#x27;re just going to bury the battery into the ground? The ground can support a lot more weight than the lighter Lithium Ion batteries. The Redox Flow&#x27;s heavier weight is not a disadvantage in the utility space.