5 ms·

No. These are best suited for stationary, long term extendable storage. Ideal for solar plants, etc.

JumpCrisscross 3y ago
> These are best suited for stationary, long term extendable storage What advantages does flow provide over non-flow chemistries in stationary contexts? Do you mean remote and stationary, thereby benefiting from refuelling?
- jillesvangurp 3y ago
  Cost, availability of materials and you can scale the battery by getting bigger tanks. The flip side is that the amount of power they can deliver doesn't scale this way, just the amount of energy storage. Also round trip efficiencies aren't great. For stationary storage size matters less.
- adrian_b 3y ago
  The flow batteries separate the energy storage part of the battery from the power producing part of the battery. Unlike in conventional batteries, you can design a battery with any combination of stored energy and of maximum power. The stored energy is determined by the volume of fluid stored in a tank, while the maximum power is determined by the surface of the electrodes. For large amounts of stored energy, a flow battery becomes much cheaper than a conventional battery, where you must increase simultaneously the energy and the power, by making bigger electrodes (or by increasing the number of electrodes, i.e. the number of batteries). Moreover, because the active substance stays fluid instead of changing phases, it is not degraded after each charge-recharge cycle, so the lifetime of a flow battery may be much greater. There may still be problems with precipitates or changes in chemical composition in old working fluids, but such problems should be easier to solve than making long-lived solid electrodes.
- jnsaff2 3y ago
  Seasonal energy storage (charge in summer and use in winter) with lithium is not feasible. If the medium would be cheap and could be pumped into arbitrarily large tanks that don’t need constant energy input to hold the charge then this could be an enabler for seasonal storage. I don’t know whether either of them are true for flow battery (yet). They are certainly not true for H2. H2 also has atrocious round trip efficiency, not sure about flow either.

> These are best suited for stationary, long term extendable storage What advantages does flow provide over non-flow chemistries in stationary contexts? Do you mean remote and stationary, thereby benefiting from refuelling?

jillesvangurp 3y ago
Cost, availability of materials and you can scale the battery by getting bigger tanks. The flip side is that the amount of power they can deliver doesn't scale this way, just the amount of energy storage. Also round trip efficiencies aren't great. For stationary storage size matters less.
adrian_b 3y ago
The flow batteries separate the energy storage part of the battery from the power producing part of the battery. Unlike in conventional batteries, you can design a battery with any combination of stored energy and of maximum power. The stored energy is determined by the volume of fluid stored in a tank, while the maximum power is determined by the surface of the electrodes. For large amounts of stored energy, a flow battery becomes much cheaper than a conventional battery, where you must increase simultaneously the energy and the power, by making bigger electrodes (or by increasing the number of electrodes, i.e. the number of batteries). Moreover, because the active substance stays fluid instead of changing phases, it is not degraded after each charge-recharge cycle, so the lifetime of a flow battery may be much greater. There may still be problems with precipitates or changes in chemical composition in old working fluids, but such problems should be easier to solve than making long-lived solid electrodes.
jnsaff2 3y ago
Seasonal energy storage (charge in summer and use in winter) with lithium is not feasible. If the medium would be cheap and could be pumped into arbitrarily large tanks that don’t need constant energy input to hold the charge then this could be an enabler for seasonal storage. I don’t know whether either of them are true for flow battery (yet). They are certainly not true for H2. H2 also has atrocious round trip efficiency, not sure about flow either.