5 ms·

Surprised there's no mention of Vanadium Redox as an alternative that solves several of these problems even better than Lithium Ion. They can be fully cycled o

Surprised there's no mention of Vanadium Redox as an alternative that solves several of these problems even better than Lithium Ion. They can be fully cycled over 100,000 times (compare to Li-ion's 400-1200, lead's 500-800) and are expected to last 20 to 30 years. They can stay in a single state for long periods of time without degradation and can be rapidly and efficiently charged or discharged. There's also no fire risk. The biggest downside is size and weight. A refrigerator sized VRB in the attic of a house would work, but that is a dealbreaker for some/most people. These certainly won't go in cars, but as stationary appliances for those with the space, they would work extremely well for solar storage. DOE factsheet: http://energy.gov/sites/prod/files/VRB.pdf http://energy.gov/sites/prod/files/VRB.pdf Wikipedia: https://en.wikipedia.org/wiki/Vanadium_redox_battery https://en.wikipedia.org/wiki/Vanadium_redox_battery

DiabloD3 11y ago
Copper hexacyanoferrate batteries are supposed to last at least 40,000 times (compared to what the study on this I read awhile back quoted as Li-ion as 400), yet have the energy density of li-ion. They just haven't produced a commercializable version of the technology yet.
masklinn 11y ago
> A refrigerator sized VRB in the attic of a house would work, but that is a dealbreaker for some/most people. Even a refrigerator-sized VRB doesn't store that much energy, that's ~650 liters so about 40MJ, under 1.5L worth of fuel. And more importantly it weights half a tonne and (assuming it has the same shape as a standard fridge) has an area density of ~1.5t/m^2.
- mikeash 11y ago
  40MJ is a bit over 11kWh, which should be enough to run a typical house overnight. My house uses something like 500W average, not counting the car, so it could run almost a full day on this. For a stationary application, half a ton doesn't seem like a big deal. Surely a normal house can hold up that much weight? That's equivalent to only six or seven people. If the weight is a problem, put it on the ground level or in the basement.
pjc50 11y ago
Personal VRBs make about as much sense as having your own gas turbine, but utility-scale ones for peak demand response make a lot of sense.
- aidenn0 11y ago
  Speaking of having your own gas turbine, that was my existence proof a while back for how to handle events where lots of people want to charge there cars all at the same time: 30MW in a trailer http://www.pwps.com/gas-turbines/30-mw-mobile.html http://www.pwps.com/gas-turbines/30-mw-mobile.html Granted there are almost certainly better solutions, but anywhere we can deliver NG to, we can deliver stupendous amounts of electricity to, for a price.
  - jhallenworld 11y ago
    Gas turbines have a loudness problem, but there are natural gas reciprocating engine co-generation plants available for your house: http://world.honda.com/powerproducts-technology/cogeneration/ http://world.honda.com/powerproducts-technology/cogeneration...
out_of_protocol 11y ago
Better flow batteries under development: https://en.wikipedia.org/wiki/Flow_battery https://en.wikipedia.org/wiki/Flow_battery Some as good as li-ion, potentially great replacement for the cars (someone actually built a car powered by flow batteries, take a look: http://www.gizmag.com/900-hp-supercar-flow-battery/31091/ http://www.gizmag.com/900-hp-supercar-flow-battery/31091/)
NickM 11y ago
compare to Li-ion's 400-1200 This may be true for some kinds of li-ion batteries, but they can be engineered to last much longer than that. Tesla's daily cycle home battery is warrantied for 5,000 cycles, for example. Assuming the battery doesn't die the day the warranty expires, this should give you at least 15 years of life. Not quite the 20 to 30 you're quoting, but current prices are much cheaper (and this seems likely to remain true, as vanadium in inherently expensive, and li-ion batteries have a head start in economies of scale). With massively reduced size and weight, shipping and installation should be much lower as well, and I suspect consumer uptake will likely be much higher for the foreseeable future.

DiabloD3 11y ago

Copper hexacyanoferrate batteries are supposed to last at least 40,000 times (compared to what the study on this I read awhile back quoted as Li-ion as 400), yet have the energy density of li-ion. They just haven't produced a commercializable version of the technology yet.

masklinn 11y ago

> A refrigerator sized VRB in the attic of a house would work, but that is a dealbreaker for some/most people. Even a refrigerator-sized VRB doesn't store that much energy, that's ~650 liters so about 40MJ, under 1.5L worth of fuel. And more importantly it weights half a tonne and (assuming it has the same shape as a standard fridge) has an area density of ~1.5t/m^2.

mikeash 11y ago
40MJ is a bit over 11kWh, which should be enough to run a typical house overnight. My house uses something like 500W average, not counting the car, so it could run almost a full day on this. For a stationary application, half a ton doesn't seem like a big deal. Surely a normal house can hold up that much weight? That's equivalent to only six or seven people. If the weight is a problem, put it on the ground level or in the basement.

pjc50 11y ago

Personal VRBs make about as much sense as having your own gas turbine, but utility-scale ones for peak demand response make a lot of sense.

aidenn0 11y ago
Speaking of having your own gas turbine, that was my existence proof a while back for how to handle events where lots of people want to charge there cars all at the same time: 30MW in a trailer http://www.pwps.com/gas-turbines/30-mw-mobile.html http://www.pwps.com/gas-turbines/30-mw-mobile.html Granted there are almost certainly better solutions, but anywhere we can deliver NG to, we can deliver stupendous amounts of electricity to, for a price.
- jhallenworld 11y ago
  Gas turbines have a loudness problem, but there are natural gas reciprocating engine co-generation plants available for your house: http://world.honda.com/powerproducts-technology/cogeneration/ http://world.honda.com/powerproducts-technology/cogeneration...

out_of_protocol 11y ago

Better flow batteries under development: https://en.wikipedia.org/wiki/Flow_battery https://en.wikipedia.org/wiki/Flow_battery Some as good as li-ion, potentially great replacement for the cars (someone actually built a car powered by flow batteries, take a look: http://www.gizmag.com/900-hp-supercar-flow-battery/31091/ http://www.gizmag.com/900-hp-supercar-flow-battery/31091/)

NickM 11y ago

compare to Li-ion's 400-1200 This may be true for some kinds of li-ion batteries, but they can be engineered to last much longer than that. Tesla's daily cycle home battery is warrantied for 5,000 cycles, for example. Assuming the battery doesn't die the day the warranty expires, this should give you at least 15 years of life. Not quite the 20 to 30 you're quoting, but current prices are much cheaper (and this seems likely to remain true, as vanadium in inherently expensive, and li-ion batteries have a head start in economies of scale). With massively reduced size and weight, shipping and installation should be much lower as well, and I suspect consumer uptake will likely be much higher for the foreseeable future.