Flow batteries have been around for at least a few decades. Early designs used iron and salt water. Newer designs are incorporating lithium. New type of ‘flow battery’ can store 10 times the energy of the next best device By Robert F. ServiceNov. 27, 2015 , 6:30 PM http://www.sciencemag.org/news/2015/11/new-type-flow-battery-can-store-10-times-energy-next-best-device From the article: "Flow batteries aren’t much different from the rechargeables we’re all used to, aside from their massive size. In conventional rechargeables, electrical charges are stored in an electrode called an anode. When discharged, electrons are pulled off the anode, fed through an external circuit where they do work, and returned to a second electrode called a cathode. Liquid electrolytes between the electrodes ferry ions through the battery to balance the charges. The batteries can be recharged by plugging them in, which forces the charges—and the ions—to flow in reverse. But in flow batteries, the charges are stored in liquid electrolytes that sit in external tanks. The charge-carrying electrolytes are then pumped through an electrode assembly, known as a stack, containing two electrodes separated by an ion-conducting membrane. This setup allows large volumes of the electrolytes to be stored in the tanks. Because those tanks have no size limit, the storage capacity of a flow battery can be scaled up as needed. That makes them ideal for storing large amounts of power for the grid."
The electrolyte needs to be liquid for the battery to operate properly. Wiki has an overview. https://en.wikipedia.org/wiki/Flow_battery
No , just say it . Is the liquid freezable ? We must know of the practical . There is a windfarm near my house . It flows to the grid and will affect the output of coal plants . Store that wind energy so that the natural system may be sufficient ? fine
The specs on some vanadium redox and zinc-bromide flow batteries show an operating temperature of about 10 C to 50 C. Some of the latest technology is showing an operating temperature as low as -5 C. It's an issue for applications in cold climates when the battery is in standby. It's not just the freezing point of the electroyte but also reduced efficiency at lower temperature. pdf file: vanadium redox batteries https://energy.gov/sites/prod/files/VRB.pdf pdf file Zinc-Bromide flow batteries. https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=18&ved=0ahUKEwiqsf2CgfLWAhWHzIMKHX-JBsY4ChAWCFEwBw&url=http%3A%2F%2Fredflow.com%2Fwp-content%2Fuploads%2F2015%2F03%2FRedflow-Understanding-the-Redflow-Battery.pdf&usg=AOvVaw2RonxK0Zgw9YUffIuYoMV5
Flow batteries are relatively large and expensive for a single home residential use. Their current applications are for electrical substations and corporate use. One of their advantages is that electrolyte tanks can be easily added ore deleted based on needed energy reserve capacity independent of other specs of the battery. This works well for substations whose demand may change with time (i.e., new houses added in a neighborhood or buildings added to a company). Rechargeable lithium batteries appear more applicable to home use. They are compact and less expensive than flow batteries.
An article about a flow battery being used in San Diego. San Diego installs massive flow battery that can power 1,000 homes Lucas Mearian March 17, 2017 https://www.computerworld.com/article/3182369/sustainable-it/san-diego-installs-massive-flow-battery-that-can-power-1000-homes.html
Down on the farm , an Amish farmer had a go at compressed air (a battery) for the farm windmill . Hey , pneumatic power tools .
