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Will zinc-air batteries ever replace lithium-ion for long-range EVs?

The public has spoken and the message is clear: an innovative and cost-effective approach to energy storage is required to enable the transformation from IC engine cars to cleaner, long-range, full electric vehicles. Lithium-ion, although viable, has a competitor on the horizon - Zinc-air. Question is: When?

No matter how proud the owners of a $400-500 per month leased Chevy Volt may boast, the cost of electrification for automobile is too high for the masses. And all this talk that it will come down when the production volume rises lacks economic common sense. It’s not the production volume that will bring the cost down for the masses this time, but technology advances and a cheaper EV fuel storage; and one with sufficient energy density that avails the same driving range as a IC engine but without a $90K price tag.

One area of the electrification of the automobile under research for many years now has been the early commercialization of the zinc-air battery for energy storage. For the record, zinc is far cheaper and far more plentiful than lithium; and due to its lower cost, avails greater energy density within the same package size for an automotive application which demands 400-500 miles of range plus fast recharging.

When I attempted a recent web search, Fluidic Energy, a for-profit corporation based in Scottsdale, Arizona showed up. It focused on the development of energy storage devices, and specifically on metal-air cell technology. Founded in 2007, as a spin-off technology company from research done at Arizona State University, it received funding from both private sources and an energy development grant from the United States Department of Energy. I emailed the firm requesting an update, but still waiting for reply. [Jan. 30, 2012 Note: see comments below for update]

I also wrote in 2010 on this subject and noted Zinc Air Inc. based in Kalispell, Montana, Their website seems more active now, but not by much with regard to advancements. Zinc Air Inc. has since developed the Zinc Redox flow battery, designed to achieve rapid payback periods while also being the greenest battery technology on the market. This competitive storage solution allows a wind farm to store and shift wind power for flexible use by utility operators.

So, where are we now for EVs?

I affirm I did not see or hear any mention of Zinc-air battery technology at the The Battery Show 2011 in Novi. Michigan this past Fall. That means we have the EV industry still steeped in lithium-ion cell technology. My visits in 2011 to just about every tech seminar, including the SAE World Congress in Detroit, revealed the same.

Although fully functional, the cost of getting an affordable, long-range vehicle using that lithium cell technology seems on the surface far more remote than ever. The general public simply cannot afford it, though, which explains why sales of Ford’s EcoBoost IC engines and GM’s Ecotec Eco models have been much, much higher.

Fact is, the lithium technology is the culprit behind an EV’s high cost, along with the lack of economic vision by the automakers, in my opinion. The most cost-effective driving range the OEMs can achieve using lithium-ion technology is between 20-40 miles, as noted by the Toyota Prius and the Chevy Volt which are hybrids, requiring an IC engine to extend the driving range.

Any more than that and the price is out the ceiling for the average buyer. Yes, and with all respect, check out the cost and size of that Nissan Leaf with a 100-mile range; and the Tesla Model S, although a fine looking vehicle, is price prohibitive for most. Another consideration is, that taxpayer subsidy is viewed by many as an insult to those who cannot afford the car even with the subsidy, but is given to those who can afford a BMW 3 Series. (I know, I read their sharp emails condemning me for comparing a Volt’s cost and size to a more-affordable Chevy Cruze.)

In Search of Zinc-air Battery Technology

Reiterating what I wrote in TorqueNews in Dec. 2010, the main advantage of utilizing zinc-air batteries for vehicle propulsion is still its energy availability, 100 times greater than that of lithium, per unit of battery energy. And that implies greater driving range, not to mention faster recharging.

The second advantage is, zinc's supply in the world is more readily available. Regarding supply just five years ago, zinc was produced at 11 mines in 6 States with Alaska being the leading zinc-producing State. Other zinc producing States included Idaho, Missouri, Montana, New York, and Washington.

According to an article in Machine Design at that time, approximately 35% of the world's supply, or 1.8 giga-tons of zinc reserves were in the United States, whereas the U.S. held less than 1% of known lithium reserves. This was supported by that reported zinc production ranked fourth in the world, after iron, aluminum and copper.

Zinc is still plentiful, which is great news; but the technology in a car battery is far from mature. While zinc has been used for many decades in small batteries for instruments and navigation beacons, use as automotive batteries has been nil and relegated to research labs. The primary development effort had been to investigate new approaches to ionic liquids and to overcome some of the problems specific to Zinc-air cells.

In the form that these electrical cells were typically manufactured, these kind of cells were not usually recharged due to dendrite buildup during the recharging cycle. This resulted in the cell shorting out and not holding a charge when the dendrites connected the anode with the cathode. So, a need for an ionic fluid that repels this condition as well as does not use water is crucial; and one was reported in 2010 in the labs.

Regardless of the challenges, which are no greater than that of lithium which have a greater end cost, the advantages against the high cost of lithium are undisputed facts that automakers need to consider, especially if they want to sell to the masses in high volume. And since the cost of cars are already beyond real affordability by the masses, and government giveaways will not last forever, the OEMs best rethink their lithium position.

Furthermore, current yearly global zinc production is, in practical terms, sufficient to produce enough zinc-air batteries to power over ten times more electric vehicles than current lithium production can support. If nothing else, it would buy the time needed until hydrogen fuel cells mature and become economically feasible to the masses. And based on my own web searches, zinc has the potential to be an onboard resource for fuel cells as well.

So, in light of 2016 to 2025 goverment mandates toward 54.5 MPG, where are the zinc-air batteries? I wish those who have them in development would start speaking up. Or are they under some insidious industry gag order?


Frank Sherosky    January 30, 2012 - 5:16PM

Just heard back from Fluidic Energy. Here is their reply:

"Thank you for your interest in Fluidic Energy. As of now we are operating in a confidential mode. Unfortunately, the information on the website is all we can provide at this time."

I guess that means I'll have to research elsewhere to get the scoop for TN readers. I'll have more on this subject for sure in the coming months, especially after I attend the 2012 SAE World Congress in Detroit.

S (not verified)    January 30, 2012 - 9:39PM

In reply to by Frank Sherosky

Frank, I share your frustration, not just on zinc-O2 but on alternative energy solutions in general. While there is some info on the internet, a lot of it is repeated or of dubious quality. Too often I read some quick news release that speaks of a new breakthrough, but fails to give proper context or qualifiers, so the reader is left with the wrong impression on the significance of the said "breakthrough".

I understand the desire of companies to keep their research confidential, but it does make things extremely difficult for the inquiring public- and I would think inhibits research collaboration as well.

Nicolas Zart    February 1, 2012 - 8:47PM

In reply to by Frank Sherosky

Hi Frank, I think as of now, zinc-air, lithium air and lithium sulfur are the next three chemistry to watch out for. The hold 3 to 5 to 15 times as much energy density than regular lithium ion. When any of these batteries will be successfully mixed with ultracapacitors, we'll see EVs that will reach well beyond the magical 500 mile range.

Anonymous (not verified)    February 2, 2012 - 10:28AM

The last sentence in your post may be near the truth. Why after all the advantages of zinc-air over lithium have been laid out, as above, are we not pursuing this intensely?

Perhaps using lithium is intended to limit the spread of electric cars and so maintain the flow of oil for as long as possible to wring all possible profits out of it until it runs down to where it is no longer profitable. From "Who Killed the Electric Car" to now, the auto industry has shown an ambivalent attitude to electrification.

One can say one is for something but choose the most complicated, expensive or inefficient way of introducing it. To speak out of both sides of one's mouth. To say "Yes electrify, yes preserve the status quo!" I believe that this is the current stance taken by the auto and oil industries.

Howard A. Johnson (not verified)    February 2, 2012 - 10:47AM

I understand the thrust of your story is that the U.S. should diversify it's battery research into zinc and not dwell so much on lithium. I think your going out on a limb by saying price reductions from production volumes don't make economic sense. Certainly, as volumes ramp up, costs WILL come down. The problem is getting the production volumes to increase in the first place. Once the price is right, there will be boatloads (literally!) of lithium coming up from Bolivia. Of course, export taxes added by the Bolivian government will affect the bottom line. Who knows how much the taxes will contribute to the end cost of the batteries. But, your right in the long run. Diversify the research. Zinc-air is a great alternative from what I can tell by my personal research. I'm still holding out for EESTOR, though my faith is rapidly dwindling. I had heard Dick Weir quoted as saying 2011 was going to be a big year for his company. wasn't. However, up from the murky depths of wishful thinking where fantasy, physics and a whole lot of faith comes Andrea Rossi and his E-Cat, which admitedly, is not a battery, but a dependable power source that will run for 6 months on a cylinder of nickel and hydrogen. If his claims pan out, you might just be plugging your HOUSE into your CAR! So much to hope's just not happending fast enough. Makes me wish I could get out and push!

Frank Sherosky    February 2, 2012 - 11:41AM

In reply to by Howard A. Johnson (not verified)

Price reductions, I agree, will occur for sure over time, BUT (in my opinion) will still be restrained by the cost of lithium which is driven by limited supplies in comparison to zinc. So, that restraint or limitation defines the basis for my statement of "lacking economic sense."

And that affects the lack of EV volume we see at this point, due to its higher cost being passed on to the masses. The cost reductions availed by zinc are far greater from the standpoint of supply within the U.S., world availability and a lower price as a commodity, which will make EVs available to far more people than we have now.

That is why I prefer zinc-air as well over Li-air as a metal-air battery. Zinc is still cheaper than lithium by every stretch and comparison. - Much appreciation for writing.

Howard A. Johnson (not verified)    February 2, 2012 - 11:59AM

In reply to by Frank Sherosky

Unfortunately, today's research is profit driven. The research money is going to go to the technologies that are perceived to turn the quickest and highest return. Right now, that's Lithium. I'm with you, Zinc is cheaper. But Lithium has the public's attention and imagination. The best you can do at this point is hope for a breakthrough in Zinc-air technology that makes it look more profitable. If that happens, we need some demo cars, pronto, to whoo the public and grab their imaginations.

Frank Sherosky    February 2, 2012 - 12:11PM

In reply to by Howard A. Johnson (not verified)

My fear and suspicion is that the automakers will use lithium as the poster boy, then say, see electrification failed as a profit maker. Cannot make any money on it. Then and only then will they go another route. It's how they think and operate.

Michael Kepros (not verified)    February 12, 2012 - 2:49PM

The zinc-air article is on point about Li system costs and economic advantages of zinc systems; however, until the electrical round-trip discharge-charge efficiency is improved zinc-air systems will be limited to markets where round-trip energy efficiency is not particularily important. For EVs & PHEVs round-trip energy efficiency is important.

Best zinc-air technology known (and have not followed recent investigations by new start-ups) is about 64% DC-DC electrical efficiency and in systems with active charging of the whole cell it is more like 55%. Until a technical breakthrough on the overvoltage for the oxygen electrode is created zinc-air systems will be stuck to more limited markets.

Note: These lower efficiencies can be acceptable in some cases for wind and solar energy storage.

Frank Sherosky    February 12, 2012 - 5:59PM

In reply to by Michael Kepros (not verified)

Interesting comment regarding the electrical efficiency that you state. It may be the real reason why companies are proposing a PbC battery or an ultra-capacitor with a zinc-air battery to handle quick energy drains from accelerations in autos. Based on your own research, do you agree?

Anonymous (not verified)    February 18, 2012 - 6:48PM

There are many companies working on the Zinc-air flow battery right now. the issue they seem to be having is recharging. however, discharging the battery seems to have zero issues. I think the solution right now is to run 2 zinc tanks. one for Zinc, the other for zinc oxide. But just run the Zinc in only one direction. recharge the zinc-oxide outside the battery.

Have refilling stations just like Gas stations today. have a 2 pump system that pumps the Zinc-oxide out of oxide tank as New Zinc is pumped into the Zinc tank. recharging battery can be just as fast as filling up Gas tank is today.

the infastructure for this system already exists. Gas stattions would only need to install Zink holding tanks. One for Charged Zinc, One for discharged Zinc-oxide. the station can recharge the spent oxide and flow back into Zinc holding tank for redistribution.

the biggest advantage to the Zinc Air flow battery is that the battery itself can be rebuilt by regular back-yard mechanics as it is a very simple design.

See Revolt ZFAB (Zinc Flow Air Battery)

Tom Samek (not verified)    February 11, 2013 - 4:36PM

What about the mechanical refueling of the battery by replacing the Zinc Oxide with fresh Zinc?

Or, is the convenience of recharging on the grid so valuable that it overrides any possibility of mechanical refueling?