Stanford team demonstrates new type of battery for long-life grid-scale storage
25 October 2012
A team from Stanford University led by Prof. Yi Cui has demonstrated a new type of safe, fast, inexpensive, long-life aqueous electrolyte battery targeted an grid-scale storage. The new battery, described in a paper published in the journal Nature Communications, relies on the insertion of potassium ions into a copper hexacyanoferrate (CuHCF) cathode and a novel activated carbon/polypyrrole hybrid anode (PPy/AC).
New types of energy storage are needed in conjunction with the deployment of solar, wind and other volatile renewable energy sources and their integration with the electric grid. No existing energy storage technology can economically provide the power, cycle life and energy efficiency needed to respond to the costly short-term transients that arise from renewables and other aspects of grid operation.—Pasta et al.
The cathode reacts rapidly with very little hysteresis;the hybrid anode uses an electrochemically active additive to tune its potential. The high-rate, high-efficiency cell has a 95% round-trip energy efficiency when cycled at a 5C rate, and a 79% energy efficiency at 50C. It also has zero-capacity loss after 1,000 deep-discharge cycles.
M. Pasta, C.D. Wessells, R.A. Huggins & Yi Cui (2012) A high-rate and long cycle life aqueous electrolyte battery for grid-scale energy storage. Nature Communications doi: 10.1038/ncomms2139
With 50C power capacity and no degradation after 1000 cycles, why isn't this being aimed at hybrid vehicles?
Even if it's not suitable for traction use, it would be worthwhile in a dual-use application. The batteries could be integrated into EV/electric bus ("Busbaar") fast-charging stations, supplying both the surge/regulation capacity required by the grid and buffering the transient loads imposed by fast-charging of large battery packs.
Posted by: Engineer-Poet | 25 October 2012 at 07:15 AM
Could points E-P. These batteries could certainly be used in fast DC charging stations to reduce peak loads on the power grid. Their use in HEVs, PHEVs and/or BEVs would also depend on their energy density and cost per kWh? That is not fully stated but could probably be improved with further development and mass production where labor cost is lower.
Posted by: HarveyD | 25 October 2012 at 08:45 AM
I doubt labor costs are going to be a significant factor in grid or EV battery manufacturing. Volumes are going to be so immense that it will pay to fully automate early on.
Since only grid is mentioned with this battery I would expect a somewhat low Whs/kg number.
Posted by: Bob Wallace | 25 October 2012 at 09:32 AM
Even the 79% efficiency is pretty good for 50C, flow batteries manage ~70-80% at 5C.
What about self-discharge? Is this viable for longer-term storage like with the flow batteries?
Would be nice to see some cost calculations to tell if this is really a breakthrough but it does look very good on paper.
If there is no degradation at all for 1000 cycles, this may mean that the battery can serve 10-20K cycles or even more.
This may make the real-life LCOE of renewable energy sources very competitive since it eliminates (finally) the variability factors.
Posted by: soltesza | 25 October 2012 at 10:51 AM
BW...have a close look at what is happening with current automated EV batteries production facilities in USA and EU versus those in China and South Korea. Their may be exceptions but a trend seems to be developing. Many of our very heavily subsidized automated plants cannot compete and have to go bankrupt or sell? Could it be different with Grid batteries production facilities?
Posted by: HarveyD | 25 October 2012 at 10:56 AM
A123's battery production is being bought (I think) by a very major battery manufacturer. The big boys may think it time to get into the game. They know how to crank out product at very high levels.
That's what it will take, manufacturers who know how to produce at enormous volume. That's why Envia is not talking about becoming a manufacturer, but licensing. Same is true of another innovative battery companys (Eos?). And a third is having their batteries made initially by an established Chinese manufacturer.
If all our subsidized plants fail I don't see that as a failure of the subsidies at all. The goal was to kick-start the EV/grid battery industry. If by seeding some small time players we brought the big operators into the game years earlier than otherwise we will have achieved our goals.
We might lose a little money if some loans are not paid back, but when you look at the $1 billion we've been spending each day to import oil, the close to $1 billion we've been spending each day to fight oil wars and the $1 billion we spend each day treating illness caused by coal emissions what's a few billion dollars of unpaid loans?
Between imported oil, oil wars, and coal-smoke damage we're spending over a $1 trillion dollars per year.
Get us into EVs and producing our electricity from renewables and we recover the lost battery plant loans in short days. And save over $1 trillion per year for, well, until the Sun cooks us in however billion years away that is.
Posted by: Bob Wallace | 25 October 2012 at 08:21 PM
Full electric vehicles should not be made or sold in the US, Europe or the UK mainly because they give people and excuse not to buy efficient hybrid vehicles and have fear. The Tesla is the electric HUMMER equivalent. It would not take much space to put a one to three kW emergency generator in the Tesla and cut the size and cost of the battery and still most owners would not have to use it much, and for an hour lunch it could put as much as 15 miles or more in the battery and allow the vehicle to move with the traffic even with a mostly empty battery. ..HG..
Posted by: Henry Gibson | 31 October 2012 at 04:14 AM
The sodium sulphur battery was invented by Ford and the ones produced by NGK are likely to be the cheapest grid storage available in the future. The ZEBRA battery, now made by FZSONIK and the GE equivalent DURATHON work well for some automotive uses and very well for UPS and grid storage and material costs are almost as low as the sodium sulphur. They require salt, iron, aluminum and far less nickel than NICADs.
where size is little object, the Vanadium flow battery works well and efficiently. ..HG..
Posted by: Henry Gibson | 31 October 2012 at 04:22 AM