And the battery improvements keep on coming

[KarenRei]

I've reported before on the many new lithium-ion battery improvements that keep turning up. So far, the most promising are anodes: lithium vanadium oxide and silicon nanowires; each allow for 2-3xing a li-ion battery's overall energy density. The latter case, the nanowires, has 8x the lithium density after the first charge (10x on the first charge) in comparison to traditional graphite anodes. Hence, with either of these techs, you take cells for which the anode is currently the bigger component and make it so the cathode is now the bigger component. All we really needed, I thought to myself, was an equivalent cathode advance.

Well, we got it:

http://www.hybridtechnologies.com/20080225

Lithium manganese cobalt nickel titanium oxide. They've doubled the energy density of the cathode, and it too allows for fast charge/discharge, like most of the new techs. :) And the beauty part? They're already producing the cathode material in industrial quantities. They expect to have their li-poly batteries, using the new cathodes, out by the end of the year. Put it all together with the new anodes, however, and you've got something like 3-5x the battery energy density. And on top of all of that, they can make the cells with varying voltages, so the packs should be able to be made to match whatever voltage Aptera's existing cells use.

Ah, I love advancing technology. Aptera, please, make our battery packs upgradeable! Assuming proportional volumentric energy density, such packs would give the Aptera Typ-1e something like 350-600 miles range @ 55mph, and ~250-450 miles range @ 80mph.

[palmer_md]

Please be wary of the hype. Yes there has been a lot of focus on batteries over the past couple of years. Most of this has been due to the fact that the battery manufacturers now see the potential for some large purchases from the auto manufacturers. Now that we are going to build PHEV and EV's there is some incentive to develop something better and get a contract with one of the auto manufacturers. I built my own EV over 12 years ago and have closely followed batteries and there have been many claims over those years about some amazing breakthroughs. Most of which never came to fruition. I do believe that we are seeing some breakthroughs and that the newer technology is going to far surpass what is available today, but I don't believe that when someone builds a AA sized battery with some outstanding performance that it can be scaled up to automotive capacity. Again we will see some big improvements, but not directly scaled. When you go from a battery that can put out 2-10 amps and then scale that up to something that can produce 300-500 amps you are goint to loose some of the efficiencies. I look foward to hearing some real world results from some of these battery packs, not just the hype about what they can do on a small scale.

I'm not trying to burst your bubble (heck they might just pull it off), but just keeping things in perspective from somone who has watched this industry for many years.

Mike

[Chupacabra]

Do they have any information available on the Typ-1h and 1e batteries and how many charges they supposed to be able to handle before requiring replacement? How about replacement costs?

[KarenRei]

Chupacabra: Nope - -Aptera hasn't decided on a battery manufacturer yet.

Palmer: Yet, it's hard to deny that batteries have been advancing at a very rapid clip. Look at cell phones from the early 90s for comparison. Yes, not everything in the laboratory makes it to market. Most don't. But still, many do. The more breakthroughs in the lab you get, the better your odds of seeing them come to market. Right now, there's about a dozen lab techs that on their own would add 50% or so to energy density, three of which would 2-3x it on their own. The odds of all of them failing is quite slim, especially with the renewed surge in investment capital.

[RoxChkPlusOny]

Aptera says the e model can net you 120 mi per charge, and that the h model can get you 40-60 mi on electricity alone. Assuming the cars are roughly identical, then the battery pack should be be 1/3 to 1/2 the capacity of the e model (I believe I heard somewhere the figure was 1/3, so can we for the sake of argument use that number?). If the e model batteries are good for 1500 charges, then the h batteries must be too, given they're the same technology. Both cars run on a solely-electric drivetrain, so the battery is responsible for all propulsion in both. Therefore, whereas the e model will be "good" for 180,000 mi, the h model would consequently be good for 60,000 mi. That seems alarming to me. If the battery pack is up to 1/2 the size of the e model, though, the number bumps up to 90,000 mi. Either way, I think it would be worth doing a comparison on schedules for price-neutrality compared to a... Corolla... for each model. Karen, wanna try that out? :-D

[KarenRei]

Good observation, Rox. Yes, PHEV batteries need to last for more cycles than BEV batteries. They're usually subjected to more stress as well.

[RoxChkPlusOny]

Do you know if any lithium battery technologies are subject to the old battery limitations that destroy carrying capacity in the face of sustained trickle charges? I'm thinking of old laptops that would do very badly if you kept them plugged in...

[KarenRei]

I'm not sure what you mean -- are you talking about NiMH, not li-ion? AFAIK, the only degradation limits for *traditional* li-ion (LiCoO2+graphite) are:

* Age: li-ion is unusual in that it loses capacity simply due to age, whether charged, uncharged, in use, etc. The rates of loss depend on charge state and temperature (cold temperatures and 40-60% charge state is best), but they'll lose capacity in any conditions over time.
* Cycles: Like all batteries, li-ion has charge/discharge cycle limits. In laptop and cellphone usage, however, age is usually a bigger factor.
* The age problem affects different devices differently. As li-ion batteries age, their internal resistance rises, which lowers the maximum current you can draw. So, devices that need a lot of peak power will consider the battery permanently dead long before devices that use less power do.
* Li-ion, like all batteries, has an upper and lower "safe" temperature range; exceeding this can damage the battery.
* Li-ion can (rarely) go into a "deep discharge" state, where it takes a long time to recover from, if it can recover at all, if left without charging current for very long periods (generally a few years).

Now, all of that said, lithium phosphate batteries are not traditional li-ion. They are designed to have far less age degradation and to be able to handle many more cycles to boot. Most modern EV designs call for lithium phosphate or other new li-ion batteries that have similar properties (titanates, spinels, etc). Only a couple use traditional li-ion -- most famously, Tesla.

[RoxChkPlusOny]

I said "lithium battery technologies", but I'm referring to the trickle charges found in older battery technologies (not sure which ones... is NiMH like this so that you would refer to it?) and wanted to know if lithium-based batteries exhibit this behavior to any degree.

[KarenRei]

Yes, NiMH has that problem. Li-ion doesn't -- neither traditional li-ion, like you find in Teslas, or any of the new chemistries.

Assuming they live up to their lifespan and safety promises, which all evidence so far seems to suggest they will, the new generation of li-ion are a dream. Almost no heat loss (typically a fraction of a percent) in charge/discharge, versus 30-50% of the energy in charging/discharging an NiMH (which not only wastes electricity, but also requires that you significantly cool your batteries). 1% electricity leakage per month, versus 5% or more for NiMH. Very resistant to permanent damage from suboptimal charge/discharge conditions, as NiMH and traditional li-ion are prone to (in different ways). And while they're not as good energy density as traditional li-ion, they're notably better than the best NiMH. And so on. Great stuff. :)

The only two constraints remaining on the modern li-ion automotive batteries are cost and energy density. Cost, for the most part, just needs mass production. Energy density is the only issue that needs new technology, which is why I follow news on new anodes and cathodes so closely.

By the way -- don't buy into any hype you may hear about "Peak Lithium". I did a writeup on the subject here:

http://www.daughtersoftiresias.org/greenwiki/Peak_lithium

Basic summary: lithium carbonate is the tiniest fraction of the total cost of lithium ion batteries. The price could increase tenfold and you'd hardly even notice it in the price of the end product. Yet, if the price 10xed, you could easily afford to, say, recover lithium from seawater, where there are essentially boundless reserves of it. And from many other sources, too; today, most facilities that extract minerals from brines don't bother to extract the lithium because the price is so low; it just gets thrown out in the tailings.

[drivin98]

There's an article at New Scientist right now on new battery tech but it's hiding behond a stupid subscription wall. >_<
http://environment.newscientist.com/channel/earth/energy-fuels/mg19726456.100-soupedup-battery-prepares-to-slay-the-gas-guzzlers.html

[KarenRei]

Eh, it'll show up eventually. :)

[drivin98]

I did come across this article (http://techon.nikkeibp.co.jp/article/HONSHI/20080129/146549/) full of info from the 48th Battery Symposium in Fukuoka. Unfortunately my schedule has been amazingly messed up this week and I'm too tired to make any sense of it.

[KarenRei]

Yeah, that link is where I found out about lithium vanadium oxide anodes. :) I swear LVO sounds like it should be a cathode material, but they say "anode" and they talk about it being paired with LiCoO2 cathodes, so they must be right. LVO is used in a Subaru concept vehicle.

There's a number of great battery techs on the horizon. It only takes one to work out in order to change the world. If both a major anode and cathode improvement work out, it's all the more dramatic of a revolution. After a century of crawling progress, rechargeable battery tech has taken to advancing incredibly rapidly, and what's in the lab right now seems to suggest that this rapid advance is going to continue for at least the next five years, probably more.

[palmer_md]

Here is an excellent primer regarding battery history.....

http://www.economist.com/printedition/displaystory.cfm?story_id=10789409

[Chupacabra]

I don't understand all the technical jargon here, but I think Aptera would be wise to make their battery bays and conditions more modular rather then propietary to allow for easier upgrades. Obviously as battery technology improves, the easier adapted it is to their vehicle the more range the vehicle will have, which in turn will make it appeal to more consumers and increase their potential customer base.

[KarenRei]

You know, I was just thinking. Tesla's batteries are arranged into "blades". Each blade has a bunch of cells in series to get the required voltage and all of the control circuitry for those cells; it's basically self contained. One blade dies, you remove it and replace it. There are multiple blades in the vehicle, designed to give it the amperage and total kWh the vehicle needs to be practical.

I think it'd be great if the Aptera was modular like that. Seems it'd make upgrades much easier. Who cares what voltage the individual cells of the new type of advanced battery are; so long as you can get blades of them at the proper voltage with proper connectors that will fit where you need them, you can use them. Or, at least, I would think it would be able to work that way. The only case, it seems, that wouldn't work is if your individual cells were high voltage (as an extreme case, the EEStor EESU, which is 3500V).

[Dubito]

Seems like each new battery technology has different cell voltage and charge/discharge curves. I’ve had to buy new chargers or at least new control chips for new battery technologies. Sometimes one lucks out, for instance a lithium polymer charger can charge 7 cell A123 packs because the charger thinks it’s a 6 cell LiPo pack, but I wouldn’t mix LiPo and A123 batteries on a single vehicle. Modular “blades” are a good idea for maintenance/repair and range adjustment/augmentation, but I don’t see mixing battery technologies.