> a typical Li-ion battery retains only 80 percent of its charge capacity after 300 to 500 cycles
That's off by 10x at least. Typical LFP batteries that are widely used now have thousands of cycles. Over 5K in some cases. Some of the solid state batteries that are coming to production in the next few years might do better. 300 to 500 is more typical of some older chemistries. Even NMC batteries used in e.g. Teslas have cycle life spans of at least 1500 or so cycles.
And for reference, if you charge and full de-charge your car that would be 1 cycle. A decade is only 3653 or so cycles (there might be 2 or 3 leap years). Most car vehicle owners don't charge nearly as often or so completely. A typical Tesla that is partially charged maybe once a week or so is not going to need a battery replacement until the 2040s or so.
Anyway, the article carefully avoids talking about energy density. Which is of course the key thing here. Together with other things like charging speeds. Operational temperatures, etc. These all matter.
This is a university study, not a plan to get this to production. Promising and interesting but probably well over a decade away from any serious applications. By that time we might have all sorts of other battery tech that is sitting a bit higher on the technological readiness scale on the market.
dragontamer 39 days ago [-]
LFP is 3000 cycles last time I checked.
NCA, a very common LiIon chemistry, is only 500 cycles as the article rightfully claims
The article is anywhere from 'correct' to off by 600% depending on which LiIon chemistry. But that's the nature of such a wide chemistry, there's so many LiIon out there it's hard to generalize.
NCA / NMC is common for phone and even EV applications though. So it's not necessarily wrong and both have similar endurance specs.
> Anyway, the article carefully avoids talking about energy density. Which is of course the key thing here.
No one cares about density in utility scale applications. It can be heavy as all heck but as long as it's cheap it will be an effective solar or wind battery.
ziga 39 days ago [-]
You can't really generalize cycles based on chemistry alone. Battery management and usage matters. But two examples with NCA/NMC chemistry:
- The Tesla Powerwall 2 battery warranty[1] is for effectively 3650 cycles (daily cycle for 10 years).
- Many cases of Tesla cars at 200k mileage (~1000 cycles, depends on battery size) with less than 15% capacity loss[2].
And these batteries didn't die after reaching the high number of cycles, they just retained less capacity.
Yes, Your phone or laptop though... that we dont have regulations that at least require manufacturers to give users the option to not charge to 100% is beyond me.
Many billions of batteries and thus billions of devices needlessly scrapped.
LUmBULtERA 39 days ago [-]
FWIW, Apple's current batteries are stated to last 1000 cycles until they reach 80% capacity. [0]
Anecdotally I have 98% capacity at 248 cycles on my 15 pro. I use an 80% charge limit as I don't use that much battery in a day.
The 80% charge limit will dramatically extend the lifespan.
It turns out the top few percent is what really damages the cells - which means there is always an inherent capacity vs cycle life tradeoff.
Qwertious 39 days ago [-]
Energy density indirectly matters in utility scale applications, since it implies the cost is more dependent on raw materials and therefore it limits how low the cost of production can get.
In contrast if the raw materials are dirt-cheap per watt-hour (because you don't require as much mass) but the manufacturing process is expensive, then over time the manufacturing process can generally be made cheaper and you can expect the batter to get cheaper quicker.
CyberDildonics 38 days ago [-]
3000 for LFP is a common number, but there are some that are now claiming 6000 cycles. Of course like everyone has mentioned, battery management matters and charging temperature, discharge temperature, charge and discharge limits matter.
megaman821 39 days ago [-]
Also for utility uses, why is 80% the benchmark? It seems likely that batteries will be used down to 60% capacity; so double the number of cycles for a reduced capacity.
39 days ago [-]
nine_k 39 days ago [-]
Also, in a utility-scale battery with literally millions of cells there will always be gradual but constant replacement of a small amount of cells, while the remaining cells continue to bear the load. This is something you can't do in a phone, and what may be too costly in a EV.
bcrl 39 days ago [-]
It doesn't quite work out for a centralized utility scale battery unless it gets built gradually over the expected lifetime of the component batteries, as most existing infrastructure projects tend to get financed and built all at once, so all the batteries are the same age and are likely to require replacement around the same time. On a small scale that is quite visible with UPS batteries in data centers that all fail at once.
The easiest way to avoid that is to slow things down and build up a decentralized grid scale battery over time through incentives.
mttch 39 days ago [-]
A few companies are cropping up to do EV battery repairs so it may be affordable to a consumer.
My thoughts are that even after 80% usage the battery still has a second life for use in home power storage. Even after that most of the battery parts can be recycled. I think that battery trade-in schemes will start to become affordable once these reuse and recycling routes are scaled up.
johnmaguire 39 days ago [-]
I find it interesting that my 2021 MBP's "health" was down to about 85% after the first year, but has only decreased to 82% after two additional years. I have 653 cycles now.
Assuming that's accurate, and batteries spend a majority of their usable lifetime around this capacity, perhaps battery estimates should be based off of the 80% capacity mark.
peer2pay 39 days ago [-]
80% SoH is the de-facto industry standard for EoL/replacement. Mostly because after that you will eventually get a "knee-point" in your degradation curve at which operation is risky and largely inefficient.
Without knowing specifics, your MBP might have had issues with an individual cell such that initial capacity dropped significantly until the cell was disconnected.
vasco 39 days ago [-]
Enough cycles and you get a free pillow so the risk comes with rewards sometimes!
formerly_proven 39 days ago [-]
I've seen several laptops start out in the 90-95% SoH range, drop off quickly to the mid-80s and stay there for a very long time. Similarly for iPhone batteries, they go below 90% pretty fast, then each % off takes longer and longer until they actually start dying. Maybe that's due to different baselines though, BMS of laptop batteries normally refer last-full energy to the design energy, which is probably just a fixed value in an EEPROM and might not ever be reached due to a more conservative charge cutoff and tolerances.
39 days ago [-]
codemiscreant 39 days ago [-]
The number is, I believe, simply peak voltage. And personally I find the measure grossly misleading: an iPhone with an 80% battery has an almost useless runtime. It definitely isn’t 80% of the original runtime.
ruszki 39 days ago [-]
My iPhone could handle about 2 days with heavy usage. It was reduced to a day after 1 year. Now after 2 and half years, the battery dies in about 12 hours with the same usage. The battery health is 83% according to iOS. So it’s definitely not a good indicator for real life usage.
Apple added a feature that only charges to 80% if you're only using it while plugged in (and discharges to 80% if not disconnected).
That made me uninstall aldente again.
apt-apt-apt-apt 39 days ago [-]
I was pretty careful with my 4.4yr old Intel MBP, nearly always using Charge Limiter to max at 80% or so.
It's at 500 cycles now, the battery has been declaring it recommends service for a year, and taking it out to cafes limits my work time to maybe 3 hours max (starting at 80%).
There were at least one or two occasions where it 'cooked' itself to death inside my backpack though, when it didn't sleep on lid close as expected.
Not sure how big an impact charge limiting has made (is my battery life better? did I avoid pillowing?). Or the self-cooking. But that has been the life of this computer.
johnmaguire 39 days ago [-]
I struggle a bit with this concept. It feels silly to me to only use 80% of my laptop's battery capacity in order to... avoid my usage bringing my battery's capacity down to 80%.
OK, so it can go below 80%, but if it takes 3-4+ years, I'm not sure I care. (Don't get me wrong - I do of course use the built-in intelligent charging on Apple and Android devices. No reason to charge a battery to 100% when I'm going to plug it in for bedtime in a few hours anyway.)
cameldrv 39 days ago [-]
It's more than just going down to 80%. After a while the battery will essentially fail entirely and not hold a charge, or swell up and push around other components of the computer, and it becomes a fire hazard.
I have an M1 MBP and I use it 95% of the time at my desk. I use Al Dente, and if I'm going to be using it away from my desk or I'm going on a trip, I'll just click the button to fully charge it. Even if I forget, the battery life is good enough that 80% is usually enough.
nicoburns 39 days ago [-]
It might make sense if you occasionally use the full 100%. But for most people I expect it makes more sense to just use 100% of the capacity and then replace the battery if/when it degrades. For some reason, many people seem to have an aversion to replacing the battery in phones. Yes, it's expensive, but those same people will often replace the entire phone which is much more expensive!
39 days ago [-]
Tagbert 39 days ago [-]
For most people they are not using 100% of capacity every day. In fact large numbers of laptops are primarily used plugged in and just move from desk to desk. In that scenario charging to 80% has no downside. The upside is that your battery may last longer. If you are keeping your laptop for longer than 2-3 years that might be worthwhile.
tzs 39 days ago [-]
The idea of not charging all the way is to get more total use out of the battery.
These batteries degrade with use. They degrade faster when they have a high charge or a low charge. Suppose each day you used 50% and charged at night. That's a cycle every two days.
If you are doing that by going from 100% to 50% and then charging back to 100% you will get some number of cycles before you need to replace the battery. Let's say it is 1000. You'd need to replace the battery after 2000 days.
If instead you do your 50% per day by going from 80% to 30% and then charging back to 80% you are operating in a charge range that has a lower degradation rate, so now you might get 1500 cycles, or 3000 days.
johnmaguire 39 days ago [-]
I understand it increases the total lifetime of the battery, and certainly I do know a few people who are still using their iPhone 8, but most people seem to replace devices every 4 years at least. I just don't find the tradeoff worth it, but I understand from some of the sibling comments that this is probably most useful for people who don't typically run on battery power.
ksec 39 days ago [-]
600 cycles in 4 years is pretty high IMO. Do you carry it around all the time without it being plugged into socket ?
36 days ago [-]
DoctorOetker 39 days ago [-]
> Anyway, the article carefully avoids talking about energy density. Which is of course the key thing here.
> The cell with F-SSAF electrolyte and pyrolytic graphite (PG) cathode show reversible capacities of 83, 81, 79, 77, and 75 mA h g−1 at the current densities of 20, 40, 60, 80, and 100 mA g−1 (Figure 2a).
so 83 Ah/kg (at 20 A/kg), and at a cell voltage of ~ 2V thats ~166 Wh/kg.
kccqzy 39 days ago [-]
> Typical LFP batteries that are widely used
It depends on the use case. I believe LCO batteries are still more widely used since they are popular in small electronic devices rather than electric vehicles. These do not achieve the thousands of cycles you mention.
In general I don't like articles that simply talk about specs of Li-ion batteries as a whole without specifying the exact chemistry. Apple has different incentives when they choose a battery as compared to say Ford.
morserer 39 days ago [-]
Li-ion != LFP.
LFP is incredible, but LFP batteries are 5x larger than li-ion. The two aren't comparable. You won't find LFP batteries in cars nor smartphones.
Animats 39 days ago [-]
BYD has raised lithium-iron phosphate Wh per liter up to lithium-ion levels. Wh per kilogram is still maybe half that of lithium-ion.
BYD "Blade battery 1": 168 Wh/kg. 448 Wh/L. Shipping now.
BYD "Blade battery 2": 210 Wh/kg. Announced for 2025. [1]
Tesla current lithium ion battery: 260 Wh/kg. 416 Wh/L[2]
(Tesla also uses lithium iron phosphate, in their lower-end cars.)
Close on size, big difference on weight. Weight differential is narrowing.
At this point, all fixed installations should be lithium iron or better. There's no excuse for big lithium-ion battery fires such as Moss Beach and the Port of Los Angeles any more.
Solid state batteries with better density are coming along, but nobody has those in volume production yet.
(Incidentally, if you ask questions like this to search engines that use an LLM, the results may be bogus, as they tend to pick numbers from the wrong places. Check the references.)
On Smartphone, First generation silicon-carbon battery, or lithium-ion battery with a silicon-carbon anode is shipping already at ~23% higher capacity. 2nd Generation is shipping this year at 40% increase over original. And hopefully 50% next year. With expected 100-200% increase by 2035.
Reason077 39 days ago [-]
> "Wh per kilogram is still maybe half that of lithium-ion."
At the pack level, it seems to be a lot less than that. If you compare a Tesla Model Y standard range (with LFP pack) to a Model Y long range (with NMC), you're looking at around 62 kWh vs 80 kWh for the latest versions, putting the difference in energy density at < 30%.
NovemberWhiskey 39 days ago [-]
Lithium-ion is an umbrella term that properly includes common cell chemistries like lithium iron phosphate (LFP), lithium nickel manganese cobalt oxide (NMC) and lithium nickel cobalt aluminium oxide (NCA).
It doesn't make sense to compare LFP vs. lithium-ion, because the first is a sub-type of the second.
Melatonic 39 days ago [-]
Most commonly when people say lithium ion they really mean lithium polymer (lipo). Usually for the other lithium ion chemistries they will specify like you Jane (LFP etc).
You are technically correct - that's just how I've seen it casually used
CyberDildonics 38 days ago [-]
Most commonly when people say lithium ion they really mean lithium polymer (lipo)
I don't think this is true. There are still lots of lithium ion 18650 cells around in battery banks, tool batteries and home devices, you name it.
Also lithium polymer is the same general chemistry (there are lots of variations), the polymer is the separator.
stevenhuang 39 days ago [-]
Yes you can be a pendant about a topic to a degree that you manage to confuse even yourself, or you can understand the term is also commonly used to refer to the typical metal oxide cathodes we all are familiar with (NMC, LCO, NCA, lipo). From context it's really the obvious interpretation.
dgacmu 39 days ago [-]
There are a lot of LFP model 3's on the road, and my understanding is it was only canceled because of manufacturing location effects on tax rebates.
A lot of BYDs cars use LFP. And they sell a -lot- of cars.
The 2024 Mach-E is LFP. The Kia EV5.
And so on. I think you have an outdated model of lfp tradeoffs.
Many of the extended range models still use higher-density chemistries. But LFP is making amazing strides.
rstuart4133 39 days ago [-]
LFP Tesla 3's is what they ship from China. Australia gets Chinese made Model 3's, so they are all LFP. The US doesn't get Chinese made Tesla's, so no LFP for you.
It doesn't seem to effect things much. The cars still have the same range. I guess they must be heavier.
Australian drive their cars around 13,000 km's per year. If the LFP battery got 3,000 cycles that's 90 years. I guess they must hit some other limit long before then.
> Tesla is known to frequently change the prices or availability of its models without providing separate information. As the US publication Electrek writes, the Model 3 Standard Range disappeared from the US configurator at the beginning of October. At 39,000 dollars, this variant was the cheapest Tesla in the US. Recently, however, only the Model 3 with the larger Long Range battery has been available there – in the rear-wheel drive version from 42,490 dollars. There is also the Model 3 Long Range with all-wheel drive (47,490 dollars) and the Model 3 Performance (54,990 dollars).
joking 39 days ago [-]
Batteries also degrade by time even if you don't charge and discharge them.
Psyonic 39 days ago [-]
While most cars are not LFP, your claim that you won't find LFP batteries in cars is incorrect:
Most Chinese-built EVs use LFP. And China is the world's largest EV market, bigger than the rest of the world combined. So presumably, the majority of EVs shipping globally are using LFP batteries today.
guerby 39 days ago [-]
And China is using LFP even for electric trucks.
Reason077 39 days ago [-]
Absolutely. Likewise most of the battery-electric buses in London (and presumably, other European cities) have always used LFP. Safety is a big consideration there as nobody wants a bus-sized battery fire in the middle of a dense city.
gertlex 39 days ago [-]
Had one in our university solar car 15 years ago, too :D
avtolik 39 days ago [-]
I read last week that about 40% of the electric cars produced now are with LFP batteries.
hnuser123456 39 days ago [-]
It would appear LFPs are making their way into EVs, despite having about half the energy/mass density.
LFP has made huge energy density improvements in recent years, so the difference is much less than that today.
If you compare a standard range Tesla Model Y with LFP pack, the newest LFP pack stores around 62 kWh, vs. around 80 kWh for the long range (NMC) variant. And the LR pack actually weighs more than the LFP one, putting the difference in energy density at <30%.
Further more, typically with an NMC pack it's recommended to only charge to 80% for day-to-day use, to reduce long-term degradation. But with an LFP pack you can routinely charge to 100%. So the effective difference in range for day-to-day driving if you follow that recommendation is small.
gruturo 39 days ago [-]
> You won't find LFP batteries in cars nor smartphones
Bold statement. Quite incorrect too. My car has one, and I'm pretty sure Tesla sold them to other people too, not just me (M3 RWD 2022)
elihu 39 days ago [-]
LFP is a type of lithium ion battery. Modern LFPs perform pretty well, though they're a bit worse than "regular" lithium ion, in part because they run at a lower nominal voltage of 3.2 volts rather than 3.6 volts. They're used in cars all the time, just not usually in the United States.
I've never heard of an LFP smartphone battery, but that doesn't mean it isn't done. I wouldn't be surprised if it was common in China.
Reason077 39 days ago [-]
> "Li-ion != LFP."
No, LFP is one form of Li-ion battery, along with other chemistries like NMC, NCA, LMO, etc.
> "LFP is incredible, but LFP batteries are 5x larger than li-ion."
Nope. Today it's more like 20-30% less energy density. And the gap has been closing over time.
> "You won't find LFP batteries in cars"
Absolutely false. The vast majority of Chinese-built EVs (brands like BFD, NIO, MG, XPeng, Geely) use LFP in many models. Most Chinese-built Teslas use LFP packs. Tesla's Powerwall 3 home storage batteries use LFP. Western automakers are also increasingly looking to LFP to reduce costs and improve stability and safety.
In fact, I'd say the significant majority of all EVs shipping in the world today contain LFP batteries.
CyberDildonics 38 days ago [-]
LFP batteries are 5x larger than li-ion
This is completely wrong. Anyone who has bought a single LFP cell knows they are close but not quite as energy dense for the weight as regular lithium ion batteries. They are very common in all sorts of applications like medical devices and cars at the very least.
You won't find LFP batteries in cars
This is also not true at all. Here is a list of 42 car models with LFP batteries including telsa model 3, model Y and the ford mustang.
When people say Li-ion they typically are talking about Lipo batteries (unfortunately). LFP obviously are much better longevity wise.
jillesvangurp 39 days ago [-]
No they are not, they are talking about batteries that contain a lot of lithium. Aside from battery nerds, the finer points of most chemistries are lost the vast majority of people and I doubt even experts would agree with your very narrow definition.
In any case, my point was that the car industry and the storage industry is dominated by a wide variety of batteries (most of them lithium based of course; some might say lithium ion even) that have way better longevity than the article suggests is the key selling point of this new battery chemistry.
I think it's a bit misleading or sloppy. I'd expect better from IEEE.
tim333 39 days ago [-]
I've been guilty of thinking of lithium polymer. Most people have no idea of battery chemistry beyond thinking of the thing that comes with their phone.
lightedman 39 days ago [-]
"300 to 500 is more typical of some older chemistries."
And this is almost purely a function of the very first charge cycle the battery receives. If the initial charge cycle is fairly aggressive, you can actually pull something like 1500 cycles out of those older chemistries, at the cost of actual capacity. We're running tests on this right now in a lab in San Diego. Almost all non-solid-state Li chemistry batteries are similarly affected.
baranul 38 days ago [-]
Clarity is very much needed. There are so many stories about "battery technology breakthroughs", but then they never come to market or are x number of years away from production. The general public is often way more interested in when they are going to actually sell the new battery technology, and getting their hands on them to put to use.
jve 39 days ago [-]
And there is such thing as DoD (Depth of Discharge) - Doing 4x 25% charges (1 cycle) is much much much better than 1x100% cycle.
High discharge rate + high energy/mass density optimized chemistries usually have the worst charge cycle degradation. LFP doesn't have top discharge rate or energy/mass density, it trades some of that off for improved long term stability.
hinkley 39 days ago [-]
The last aluminum battery discussed here only had about 40% of the volumetric density of Lion and did not mention wh/kg, just w/kg. Which sounds a lot like lying with statistics.
amatecha 39 days ago [-]
LFP !== Li-ion.
If you "full de-charge" your car battery that battery is toast, so that's not a useful comparison.
gnabgib 39 days ago [-]
LFP is certainly a Li-ion battery chemistry (and also a Lithium Iron chemistry).
Sure, and I'm no expert on the subject, but when someone writes "a typical Li-ion battery" they mean the common rechargeable lithium battery with lithium cobalt oxide, not lithium iron phosphate. LiFePo4 is not a "typical" Li-ion chemistry yet, unfortunately.
ikigai_sign 39 days ago [-]
I got so burned on QuantumScape stock I haven't been able to think about solid state batteries since then.
toss1 39 days ago [-]
You are not alone, sadly.
ErigmolCt 39 days ago [-]
I think by the time it's commercially ready (if ever), the battery landscape could look very different
moron4hire 39 days ago [-]
Oh, but they should be able to get that time down to a few months if they just use an LLM.
39 days ago [-]
kvakerok 39 days ago [-]
Came here to ask about energy density, but it seems the article answered it without answering it.
hilbert42 39 days ago [-]
Spectrum: "…its energy density will need to be improved, the researchers say."
"Anyway, the article carefully avoids talking about energy density. Which is of course the key thing here."
I agree. And as you say, there's a bit of inaccuracy in the article. In fact, it's more than just a little—not to mention the omissions.
What's so annoying about this article is that it's from the IEEE's magazine Spectrum where one expects the best—the most authorative, factual and most current—technical information available at publication time but it's often not the case.
Unfortunately, in recent years, the IEEE has been unduely influenced by commercial interests which has affected or slanted the accuracy of its reporting of science and engineering news. As Spectrum is the main face of the organization and its principal news outlet this is where the policy shift has been most obvious.
I could give other instances of bad or overly enthusiastic reporting of new tech where known downsides were either not reported and or downplayed but I'll refrain here as I don't have the issues of Spectrum immediately to hand to give specific references. Suffice to say, I became so disillusioned with stuff I was reading in Spectrum† that I terminated my 20-year-plus IEEE membership some while back.
My main criticism of this story is—as you correctly point out—carefully avoids talking about energy density, which has to be a crucial aspect of any story about new battery tech that's posited as a potential competitor and or replacement for Li-ion. That's damn obvious. If the researchers did not provide numerical comparisons (experimental and or theoretical) of the energy densities between their Al-ion prototypes and Li-ion in their paper/press release then Spectrum's editor should have provided a side/footnote on the matter.
Most of us already know that Li has a larger electrode potential‡ than Al, so Al is already coming from behind Li in this regard, but of course that's far from the end of the story as there are many other factors involved in addition to those benefits as promulgated by the researchers, namely recharge cycles, safety and cost. For example, how does Al stack up against Li as far as electrode surface area (spongy metal surfaces, etc.)? We know from long experience with electrolytic capacitors that Al can be treated to have very large effective surface areas, in fact they can be enormous. If Al has the potential to be much better than Li in this regard then this new tech could certainly be a winner. As this is an obvious factor, Spectrum's editor should have mentioned it amongst others even if not mentioned in the original paper (in fact, Spectrum should have criticized its omission if the case).
In summary, one would hope this research leads to much better and safer batteries but the IEEE—as the premier representative for electrical and electronic engineering/engineers—has done precious little in providing us with information that actually matters.
__
† Whilst I've strong criticisms of the IEEE not all are negative, many of its specialist publications are quite excellent including Proceedings of the IEEE.
‡ From Wiki: Standard electrode potentials:
Li: Li+ + e− ⇌ Li(s) -3.0401V
Al: Al3+ + 3e− ⇌ Al(s) -1.662V
Edit: It was only after I'd written this comment that I was able access the original ACS research paper (initially I'd difficulty downloading it). I've since skimmed it several times and I need to read it thoroughly to get a proper understanding but it's pretty short on the issues I've raised. Thus, my point that Spectrum should have mentioned these shortfalls still stands.
_Microft 40 days ago [-]
The link to the paper is hidden a few links into the article (what's up with all these 'tags' that they link to?):
Seems to be fluoro-chemistry; use of AIF3 and Fluoroethylene carbonate. The F ion sets off alarm bells, but I have no idea whether this is significantly more toxic than the corresponding chemistry of regular Li batteries.
IndrekR 39 days ago [-]
Lithium tetrafluoroborate and hexafluorophosphate are quite common ingredients in lithium battery electrolytes.
AngryData 39 days ago [-]
If you want a battery that will last a really long time, nickel-iron batteries already do that. They have 50+ year life spans and are incredibly robust. And if you care about recycling, well its just nickel and iron. The nickel you obviously would want back, but the iron is worth almost nothing.
Until we can surpass current lithium batteries in energy density, cycle stability, and safety all at once, iron-nickel is more than good enough to be used in any application where current lithium tech struggles, and will outlive you along with being infinitely recyclable and basically as safe as any battery ever could be.
adrian_b 39 days ago [-]
Nickel-iron batteries self-discharge quickly, so they are not suitable for long-term energy storage.
tryptophan 39 days ago [-]
1% per day which is the number I found doesn't seem terrible for solar type systems.
nine_k 39 days ago [-]
This may be an issue for very small draws, like a TV remote. This can be moot in situations of constant recharge and only staying without any recharge for 2-3 days, rarely, like in utility-scale renewable generation (solar, wind).
They seem to cost much more per kWh than LiFePO4 batteries though.
pjc50 39 days ago [-]
These have been around for a while. I remember the Center For Alternative Technology in Wales was using them for their solar array, twenty years ago. However, all the more recent deployments are using lithium based cells.
I'm guessing the weight (energy density) issue matters for overall costs because of shipping?
ErigmolCt 39 days ago [-]
The real challenge is finding a chemistry that balances density, stability and sustainability without major compromises
userbinator 39 days ago [-]
They have 50+ year life spans
Exactly the sort of thing the planned-obsolescence cartel doesn't want.
anarchonurzox 39 days ago [-]
It really feels like progress in battery tech is unlocking the next "wave" of hardware development. Miniaturization leading to better drones, wearables, cameras, etc., and alt-batteries with better cycle efficiency to better usage of "green" technology. I love seeing these kinds of physical and chemical engineering breakthroughs, even if they aren't quite ready for industrial use.
GuB-42 39 days ago [-]
Battery tech improvement has stayed mostly quiet because we never really had an impressive breakthrough, instead, we had decades of slightly better and slightly cheaper stuff, and it added up. Now we have drones, electric vehicles, grid scale storage, rechargeable batteries so cheap we put them in disposable products, battery power tools that match corded and gas options.
EVs in particular are entirely about batteries. The energy density of fossile fuels is the only thing going for combustion engines. Electric motors are simpler, cheaper, more efficient, more powerful, better for the environment, the only problem is storing the electricity needed to power them. Electric cars actually came before gas cars, that's 19th century tech! The only reason we are only starting to see them back on the roads is because until now, we didn't have good enough batteries.
I expect such research to pay off eventually in the same way. No big breakthrough, but maybe in the future, you will look into buying a new car and realize that that $10k electric car you thought would be useless actually has decent range, that the generator section in the hardware store has been mostly taken over by battery packs and that city buses do not sound the same as they did before.
technothrasher 39 days ago [-]
> Electric cars actually came before gas cars
They essentially both came about at the same time. They were both being actively developed during much of the 19th century, with the first real marketable versions of each coming in the later half of the 1880's.
ErigmolCt 39 days ago [-]
Absolutely! Battery advancements seem to be the bottleneck for so many emerging technologies
megaman821 40 days ago [-]
If these non-lithium battery chemistries had any chance, it would be in grid storage. As time goes on LFPs keep getting cheaper and better, and there will be little market left for alt-chemistries.
ajross 40 days ago [-]
Lithium is rare enough to always be a cost barrier vs. something like Al/Cl chemistries that are literally made of dirt and brine. It's true that grid storage looks like the biggest market, but there's a lot of space in non-mobile/less-mobile energy storage that would like cheap batteries.
hedora 39 days ago [-]
Lithium is not rare. It is also extracted from dirt and brine. Compare copper, lithium and nitrogen on this chart (abundance and annual production):
The cost difference (which is only 4x vs aluminum, apparently) is due to a combination of increased demand (not enough production capacity) and probably the amount of energy/environmental impact of the two processes (you have to go through a lot less ore/brine to get the aluminum).
Also, aluminum benefits from a robust recycling infrastructure that hasn’t come online for lithium yet.
zdragnar 39 days ago [-]
Aluminum's recycling infrastructure is based entirely on reusing essentially raw aluminum, and only exists because bauxite is so expensive to smelt without access to dedicated hydroelectric dams.
Recycling lithium in the form of extracting from batteries produces a significant amount of chemical waste, meaning that the cost savings of recycling is significantly less when compared with the difference between smelting and recycling aluminum.
adrian_b 39 days ago [-]
Lithium is enriched in the upper crust of the Earth about 10 times over its average abundance, which makes it appear more abundant.
Even so, despite the enrichment it remains about 500 times less abundant than aluminum (in atom numbers, which matter for batteries; in weight the lighter lithium would appear even less abundant).
Moreover, the lower concentration of lithium in typical lithium ores means that for mining equal amounts of lithium and aluminum the environmental effects of mining lithium would be much worse, because more rocks are disturbed and more waste is produced.
So there is no doubt that replacing lithium with aluminum for large-scale energy storage is a more sustainable option.
dangrossman 39 days ago [-]
About 40% of lithium is "mined" from brine rather than hard rock sources, at least. Much less destructive and less carbon intensive.
jeffbee 39 days ago [-]
Lithium was $61/kg 2 years ago and now it's $14/kg. It is neither rare nor expensive.
ajross 39 days ago [-]
Spot price for Al is $2.50 as I type this. Lithium is rare and expensive in context, yeah.
pfdietz 39 days ago [-]
You're giving the price of lithium carbonate, not lithium. Li is only 18.7% of LiCO3.
jeffbee 39 days ago [-]
I am giving a direct comparison between the same commodity at two points in time. Whatever people thought was true about the preciousness of lithium between 2021-2023 when the price rose 8x obviously needs reconsideration in 2025 after the price went right back down to where it had been.
Lithium is not super precious, but its price is still a non-trivial multiply of aluminium's price.
Your graphs show it. They also show that there has not been a substantial reduction in its price over the years.
This means there is market potential for other (al/sodium) chemistries, mainly for grid-level storage.
burnerthrow008 39 days ago [-]
This seems to ignore the entire supply/demand context of both metals. Demand for Al is basically flat, and the supply/demand relationship has reached an equilibrium.
Electric cars (by far the biggest consumer of lithium) have been experiencing a an average compounded growth of something like 50% per year for the past 10 years. Li production is still catching up. The earth has plenty of Li deposits but there is a lead time to purchase the heavy machines needed to turn those deposits into productive mines.
Once electric car growth hits the inflection point on the adoption curve, and growth becomes sub-exponential, we'll start to see major downward pressure on Li prices.
jeffbee 39 days ago [-]
If we're just racing to the cheapest available reactants, iron flow batteries are going to win that race. And, unlike these others, there are already iron flow batteries on the grid.
pfdietz 39 days ago [-]
You made a statement (that it is neither rare nor expensive) that is about the absolute price of the commodity, not its price relative to another point in time. Lithium is not expensive compared to, say, gold, but it is expensive compared to, say, copper, never mind aluminum or iron.
39 days ago [-]
mlhpdx 39 days ago [-]
As a boater, I find salt being used to reduce corrosion a bit ironic.
chris_va 39 days ago [-]
Or ionic? :)
On a boat, Aluminum "corrodes" and forms an oxide layer (also known as sapphire), which then protects it from further corrosion. But, said layer is not electrically conductive (or in this case does not allow Al ions to flow into the electrolyte), so you need something to prevent the protective layer from forming.
ErigmolCt 39 days ago [-]
I think there's some hidden life lesson here: the same chemical process can be beneficial in one scenario and a hindrance in another
jokoon 40 days ago [-]
I am too lazy to copy paste the battery check list
metadat 39 days ago [-]
Yes, IMHO this is the appropriate response. What is the energy density and charge retention of aluminum salt compared to a lithium ion battery chemistry? TFA doesn't bother to divulge these critical figures.
Thank you for your submission of proposed new revolutionary battery technology. Your new technology claims to be superior to existing lithium-ion technology and is just around the corner from taking over the world. Unfortunately your technology will likely fail, because:
[ ] it is impractical to manufacture at scale.
[ ] it will be too expensive for users.
[ ] it suffers from too few recharge cycles.
[ ] it is incapable of delivering current at sufficient levels.
[ ] it lacks thermal stability at low or high temperatures.
[ ] it lacks the energy density to make it sufficiently portable.
[ ] it has too short of a lifetime.
[ ] its charge rate is too slow.
[ ] its materials are too toxic.
[ ] it is too likely to catch fire or explode.
[ ] it is too minimal of a step forward for anybody to care.
[ ] this was already done 20 years ago and didn't work then.
[ ] by this time it ships li-ion advances will match it.
> [ ] it lacks the energy density to make it sufficiently portable.
... only matters for mobility applications. You can forget about this one for grid storage.
belval 40 days ago [-]
For some reason people downvote you, but batteries seem to have this constant flux of N=1 articles explaining why X new chemistry is about to dethrone lithium. When it's not aluminium, it's solid state. This article itself has several red flags:
> In contrast, a typical Li-ion battery retains only 80 percent of its charge capacity after 300 to 500 cycles, depending on conditions.
LiFePO4 lasts for about 3000 cycles before 80% degradation, not 300-500.
> The batteries were also tested at temperatures as high as 200 degrees Celsius
Thermal runaway on LFP is 120C, not 200 but still not a temperature you will easily hit.
And finally (as always):
> before the Al-ion battery is ready for commercial applications, its energy density will need to be improved
Which means it's not commercially viable.
LiFePO4 is cheap to manufacture, uses lithium, iron, phosphate, all of which are fairly plentiful and lasts for over 3000 cycles (before reaching 80% capacity).
hedora 39 days ago [-]
In defense of them, 99% capacity retention after 10,000 cycles is still much better.
I wonder if they are quoting unrealistic 0-100% numbers and you are quoting realistic 20-80%. If so, and you multiply the Li capacity by 0.6, I wonder how far off aluminum's (undisclosed) density is.
On an unrelated note, I’m surprised that lithium is only 4x the price of aluminum. They’re both incredibly common elements, but lithium extraction is harder for a lot of reasons.
pfdietz 39 days ago [-]
I don't think lithium is 4x the price of aluminum.
In January 2025, the North America price of lithium carbonate was $9.37/kg. But lithium carbonate is just 18.7% lithium, so the price is $50/kg of contained lithium.
In comparison, the current market price of aluminum metal is $2.62/kg. And aluminum compounds (where the large energy expenditure needed to reduce Al(+3) to the metal is not needed) should be cheaper.
Aluminum is much more common than lithium. It's the third most abundant element in the Earth's continental crust after oxygen and silicon.
silon42 39 days ago [-]
> 99% capacity retention after 10,000
This would be really useful for plugin hybrids, even if the density is not competitive with LFP for pure EVs.
tim333 39 days ago [-]
Consumer gadgets too. I tend to replace the Li-ion batteries in my phones and laptops every 2 or 3 years and it's a pain. I'd pay extra for something that lasted a decade.
dghlsakjg 39 days ago [-]
Consumer electronics use Lithium Polymer generally, which has one of the lower useful lifespans.
Just replacing it with LiFePo batteries would give you 4x the lifetime. Of course, with current technology the battery would have to be twice the size.
Dylan16807 39 days ago [-]
> In defense of them, 99% capacity retention after 10,000 cycles is still much better.
Maybe, maybe not. The number that would actually matter is capacity in joules after 10,000 cycles, not the percentage.
rbanffy 39 days ago [-]
> Which means it's not commercially viable.
Depends more on price than anything else. Maybe won't replace phone batteries, but a stationary battery for home or a utility-sized one that uses less temperamental chemistry would be very welcome.
asddubs 39 days ago [-]
red flag #1 is before the article even starts
picture of AA batteries
>Lithium-ion batteries like these currently dominate the market, but aluminum-based alternatives could be a better solution
moron4hire 40 days ago [-]
> But before the Al-ion battery is ready for commercial applications, its energy density will need to be improved
There it is. No mention of how much. Though they do tell you how much longer it lasts! So apparently we aren't that averse to numbers.
brohee 40 days ago [-]
Energy density is only an issue if you move the battery around, grid storage doesn't care so a bit concerning they don't mention that usage either.
bArray 40 days ago [-]
I think grid storage does care:
* Size is important, because they need to be stored and maintained somewhere. The larger the energy storage, the more infrastructure required.
* Weight typically scales cost (the heavier it is the more it costs). If it really weighs a lot, you need to reinforce the ground too.
* Efficiency in charging and discharging. You also need to monitor the state of each cell carefully.
hedora 40 days ago [-]
Grid storage can reuse post-consumer batteries.
Li-ion capacity fall off is a fixed percentage per year, so when your car hits 80% of original capacity in ten years, its battery pack can just be used for another ten years. It’ll provide > 64% capacity at the end of that (grid workloads are less stressful than driving workloads).
So, the alternative battery technology has to cost less than the cost difference between refurbishing and recycling old car batteries. That delta might be negative.
capitainenemo 39 days ago [-]
There's been a few grid storage fires in the news, you'd think refurbishing/recycling would increase the risk. If the aluminium batteries are significantly less explosive, that might tip that balance?
hamilyon2 39 days ago [-]
At some point scaling up you start to compete with giant pile of heated sand. And it is tough capacity/price benchmark.
Melatonic 39 days ago [-]
Sounds like it could potentially be a cheaper (and maybe less fire prone) battery where weight and volume is less of a concern - maybe batteries for residential / commercial buildings or grid storage ?
Possible also easier recycling - especially locally close to the battery.
Even compared to LFP (much higher cycle longevity than the article quotes) these sound like they retain energy capacity much better
squeedles 39 days ago [-]
I thought one of the biggest barriers to Al-ion use was large dimensional change with charge state introducing mechanical stresses. No discussion of that, but a viable solid state electrolyte is pretty sweet.
elihu 39 days ago [-]
It's mentioned in the article. They say it doesn't change dimensions all that much when charging/discharging.
A large number of these sometimes smell like an oil lobby working their contacts to convince people to put off their EV purchase for five years until the amazing and better battery (tm) comes out.
I can't tell if this is one of those. It does have many of the hallmarks.
> a typical Li-ion battery retains only 80 percent of its charge capacity after 300 to 500 cycles
That's off by 10x at least. Typical LFP batteries that are widely used now have thousands of cycles. Over 5K in some cases. Some of the solid state batteries that are coming to production in the next few years might do better. 300 to 500 is more typical of some older chemistries. Even NMC batteries used in e.g. Teslas have cycle life spans of at least 1500 or so cycles.
And for reference, if you charge and full de-charge your car that would be 1 cycle. A decade is only 3653 or so cycles (there might be 2 or 3 leap years). Most car vehicle owners don't charge nearly as often or so completely. A typical Tesla that is partially charged maybe once a week or so is not going to need a battery replacement until the 2040s or so.
Anyway, the article carefully avoids talking about energy density. Which is of course the key thing here. Together with other things like charging speeds. Operational temperatures, etc. These all matter.
This is a university study, not a plan to get this to production. Promising and interesting but probably well over a decade away from any serious applications. By that time we might have all sorts of other battery tech that is sitting a bit higher on the technological readiness scale on the market.
NCA, a very common LiIon chemistry, is only 500 cycles as the article rightfully claims
The article is anywhere from 'correct' to off by 600% depending on which LiIon chemistry. But that's the nature of such a wide chemistry, there's so many LiIon out there it's hard to generalize.
NCA / NMC is common for phone and even EV applications though. So it's not necessarily wrong and both have similar endurance specs.
> Anyway, the article carefully avoids talking about energy density. Which is of course the key thing here.
No one cares about density in utility scale applications. It can be heavy as all heck but as long as it's cheap it will be an effective solar or wind battery.
- The Tesla Powerwall 2 battery warranty[1] is for effectively 3650 cycles (daily cycle for 10 years).
- Many cases of Tesla cars at 200k mileage (~1000 cycles, depends on battery size) with less than 15% capacity loss[2].
And these batteries didn't die after reaching the high number of cycles, they just retained less capacity.
[1] https://energylibrary.tesla.com/docs/Public/EnergyStorage/Po...
[2] https://insideevs.com/news/723734/tesla-model-3y-battery-cap...
Many billions of batteries and thus billions of devices needlessly scrapped.
Anecdotally I have 98% capacity at 248 cycles on my 15 pro. I use an 80% charge limit as I don't use that much battery in a day.
[0] https://9to5mac.com/2024/02/20/iphone-15-battery-lifescyle-s...
It turns out the top few percent is what really damages the cells - which means there is always an inherent capacity vs cycle life tradeoff.
In contrast if the raw materials are dirt-cheap per watt-hour (because you don't require as much mass) but the manufacturing process is expensive, then over time the manufacturing process can generally be made cheaper and you can expect the batter to get cheaper quicker.
The easiest way to avoid that is to slow things down and build up a decentralized grid scale battery over time through incentives.
E.g. https://cedarelectric.co.uk/electric-and-hybrid-battery-repa...
My thoughts are that even after 80% usage the battery still has a second life for use in home power storage. Even after that most of the battery parts can be recycled. I think that battery trade-in schemes will start to become affordable once these reuse and recycling routes are scaled up.
Assuming that's accurate, and batteries spend a majority of their usable lifetime around this capacity, perhaps battery estimates should be based off of the 80% capacity mark.
Without knowing specifics, your MBP might have had issues with an individual cell such that initial capacity dropped significantly until the cell was disconnected.
That made me uninstall aldente again.
It's at 500 cycles now, the battery has been declaring it recommends service for a year, and taking it out to cafes limits my work time to maybe 3 hours max (starting at 80%).
There were at least one or two occasions where it 'cooked' itself to death inside my backpack though, when it didn't sleep on lid close as expected.
Not sure how big an impact charge limiting has made (is my battery life better? did I avoid pillowing?). Or the self-cooking. But that has been the life of this computer.
OK, so it can go below 80%, but if it takes 3-4+ years, I'm not sure I care. (Don't get me wrong - I do of course use the built-in intelligent charging on Apple and Android devices. No reason to charge a battery to 100% when I'm going to plug it in for bedtime in a few hours anyway.)
I have an M1 MBP and I use it 95% of the time at my desk. I use Al Dente, and if I'm going to be using it away from my desk or I'm going on a trip, I'll just click the button to fully charge it. Even if I forget, the battery life is good enough that 80% is usually enough.
These batteries degrade with use. They degrade faster when they have a high charge or a low charge. Suppose each day you used 50% and charged at night. That's a cycle every two days.
If you are doing that by going from 100% to 50% and then charging back to 100% you will get some number of cycles before you need to replace the battery. Let's say it is 1000. You'd need to replace the battery after 2000 days.
If instead you do your 50% per day by going from 80% to 30% and then charging back to 80% you are operating in a charge range that has a lower degradation rate, so now you might get 1500 cycles, or 3000 days.
But it's right there in the article:
https://pubs.acs.org/doi/pdf/10.1021/acscentsci.4c01615?down...
> The cell with F-SSAF electrolyte and pyrolytic graphite (PG) cathode show reversible capacities of 83, 81, 79, 77, and 75 mA h g−1 at the current densities of 20, 40, 60, 80, and 100 mA g−1 (Figure 2a).
so 83 Ah/kg (at 20 A/kg), and at a cell voltage of ~ 2V thats ~166 Wh/kg.
It depends on the use case. I believe LCO batteries are still more widely used since they are popular in small electronic devices rather than electric vehicles. These do not achieve the thousands of cycles you mention.
In general I don't like articles that simply talk about specs of Li-ion batteries as a whole without specifying the exact chemistry. Apple has different incentives when they choose a battery as compared to say Ford.
LFP is incredible, but LFP batteries are 5x larger than li-ion. The two aren't comparable. You won't find LFP batteries in cars nor smartphones.
BYD "Blade battery 1": 168 Wh/kg. 448 Wh/L. Shipping now.
BYD "Blade battery 2": 210 Wh/kg. Announced for 2025. [1]
Tesla current lithium ion battery: 260 Wh/kg. 416 Wh/L[2]
(Tesla also uses lithium iron phosphate, in their lower-end cars.)
Close on size, big difference on weight. Weight differential is narrowing.
At this point, all fixed installations should be lithium iron or better. There's no excuse for big lithium-ion battery fires such as Moss Beach and the Port of Los Angeles any more.
Solid state batteries with better density are coming along, but nobody has those in volume production yet.
(Incidentally, if you ask questions like this to search engines that use an LLM, the results may be bogus, as they tend to pick numbers from the wrong places. Check the references.)
[1] https://electric.guide/renewable-energy-storage/byd-blade-ba...
[2] https://en.wikipedia.org/wiki/Lithium-ion_battery
At the pack level, it seems to be a lot less than that. If you compare a Tesla Model Y standard range (with LFP pack) to a Model Y long range (with NMC), you're looking at around 62 kWh vs 80 kWh for the latest versions, putting the difference in energy density at < 30%.
It doesn't make sense to compare LFP vs. lithium-ion, because the first is a sub-type of the second.
You are technically correct - that's just how I've seen it casually used
I don't think this is true. There are still lots of lithium ion 18650 cells around in battery banks, tool batteries and home devices, you name it.
Also lithium polymer is the same general chemistry (there are lots of variations), the polymer is the separator.
A lot of BYDs cars use LFP. And they sell a -lot- of cars.
The 2024 Mach-E is LFP. The Kia EV5.
And so on. I think you have an outdated model of lfp tradeoffs.
Many of the extended range models still use higher-density chemistries. But LFP is making amazing strides.
It doesn't seem to effect things much. The cars still have the same range. I guess they must be heavier.
Australian drive their cars around 13,000 km's per year. If the LFP battery got 3,000 cycles that's 90 years. I guess they must hit some other limit long before then.
> Tesla is known to frequently change the prices or availability of its models without providing separate information. As the US publication Electrek writes, the Model 3 Standard Range disappeared from the US configurator at the beginning of October. At 39,000 dollars, this variant was the cheapest Tesla in the US. Recently, however, only the Model 3 with the larger Long Range battery has been available there – in the rear-wheel drive version from 42,490 dollars. There is also the Model 3 Long Range with all-wheel drive (47,490 dollars) and the Model 3 Performance (54,990 dollars).
Rivian switched to LFP: https://insideevs.com/news/720396/2025-rivian-r1s-r1t-lfp-ba...
Some Teslas use LFP: https://www.notateslaapp.com/news/2464/tesla-lfp-batteries-c...
https://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery
If you compare a standard range Tesla Model Y with LFP pack, the newest LFP pack stores around 62 kWh, vs. around 80 kWh for the long range (NMC) variant. And the LR pack actually weighs more than the LFP one, putting the difference in energy density at <30%.
Further more, typically with an NMC pack it's recommended to only charge to 80% for day-to-day use, to reduce long-term degradation. But with an LFP pack you can routinely charge to 100%. So the effective difference in range for day-to-day driving if you follow that recommendation is small.
Bold statement. Quite incorrect too. My car has one, and I'm pretty sure Tesla sold them to other people too, not just me (M3 RWD 2022)
I've never heard of an LFP smartphone battery, but that doesn't mean it isn't done. I wouldn't be surprised if it was common in China.
No, LFP is one form of Li-ion battery, along with other chemistries like NMC, NCA, LMO, etc.
> "LFP is incredible, but LFP batteries are 5x larger than li-ion."
Nope. Today it's more like 20-30% less energy density. And the gap has been closing over time.
> "You won't find LFP batteries in cars"
Absolutely false. The vast majority of Chinese-built EVs (brands like BFD, NIO, MG, XPeng, Geely) use LFP in many models. Most Chinese-built Teslas use LFP packs. Tesla's Powerwall 3 home storage batteries use LFP. Western automakers are also increasingly looking to LFP to reduce costs and improve stability and safety.
In fact, I'd say the significant majority of all EVs shipping in the world today contain LFP batteries.
This is completely wrong. Anyone who has bought a single LFP cell knows they are close but not quite as energy dense for the weight as regular lithium ion batteries. They are very common in all sorts of applications like medical devices and cars at the very least.
You won't find LFP batteries in cars
This is also not true at all. Here is a list of 42 car models with LFP batteries including telsa model 3, model Y and the ford mustang.
https://evdb.nz/ev-battery
Where were you seeing your information?
That’s not correct.
The MG4 uses LFP. So does some Model Y and Model 3s from Tesla.
See a long list here: https://evdb.nz/ev-battery
Cars with LFP batteries: https://evdb.nz/ev-battery
In any case, my point was that the car industry and the storage industry is dominated by a wide variety of batteries (most of them lithium based of course; some might say lithium ion even) that have way better longevity than the article suggests is the key selling point of this new battery chemistry.
I think it's a bit misleading or sloppy. I'd expect better from IEEE.
And this is almost purely a function of the very first charge cycle the battery receives. If the initial charge cycle is fairly aggressive, you can actually pull something like 1500 cycles out of those older chemistries, at the cost of actual capacity. We're running tests on this right now in a lab in San Diego. Almost all non-solid-state Li chemistry batteries are similarly affected.
You'd lose 27% of capacity vs 8% capacity over a cycle test that lasted 2,5 years. https://youtu.be/i31x5JW361k?si=93KYNqKFVJRgSbKs&t=1216
If you "full de-charge" your car battery that battery is toast, so that's not a useful comparison.
https://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery
"Anyway, the article carefully avoids talking about energy density. Which is of course the key thing here."
I agree. And as you say, there's a bit of inaccuracy in the article. In fact, it's more than just a little—not to mention the omissions.
What's so annoying about this article is that it's from the IEEE's magazine Spectrum where one expects the best—the most authorative, factual and most current—technical information available at publication time but it's often not the case.
Unfortunately, in recent years, the IEEE has been unduely influenced by commercial interests which has affected or slanted the accuracy of its reporting of science and engineering news. As Spectrum is the main face of the organization and its principal news outlet this is where the policy shift has been most obvious.
I could give other instances of bad or overly enthusiastic reporting of new tech where known downsides were either not reported and or downplayed but I'll refrain here as I don't have the issues of Spectrum immediately to hand to give specific references. Suffice to say, I became so disillusioned with stuff I was reading in Spectrum† that I terminated my 20-year-plus IEEE membership some while back.
My main criticism of this story is—as you correctly point out—carefully avoids talking about energy density, which has to be a crucial aspect of any story about new battery tech that's posited as a potential competitor and or replacement for Li-ion. That's damn obvious. If the researchers did not provide numerical comparisons (experimental and or theoretical) of the energy densities between their Al-ion prototypes and Li-ion in their paper/press release then Spectrum's editor should have provided a side/footnote on the matter.
Most of us already know that Li has a larger electrode potential‡ than Al, so Al is already coming from behind Li in this regard, but of course that's far from the end of the story as there are many other factors involved in addition to those benefits as promulgated by the researchers, namely recharge cycles, safety and cost. For example, how does Al stack up against Li as far as electrode surface area (spongy metal surfaces, etc.)? We know from long experience with electrolytic capacitors that Al can be treated to have very large effective surface areas, in fact they can be enormous. If Al has the potential to be much better than Li in this regard then this new tech could certainly be a winner. As this is an obvious factor, Spectrum's editor should have mentioned it amongst others even if not mentioned in the original paper (in fact, Spectrum should have criticized its omission if the case).
In summary, one would hope this research leads to much better and safer batteries but the IEEE—as the premier representative for electrical and electronic engineering/engineers—has done precious little in providing us with information that actually matters.
__
† Whilst I've strong criticisms of the IEEE not all are negative, many of its specialist publications are quite excellent including Proceedings of the IEEE.
‡ From Wiki: Standard electrode potentials:
Li: Li+ + e− ⇌ Li(s) -3.0401V
Al: Al3+ + 3e− ⇌ Al(s) -1.662V
Edit: It was only after I'd written this comment that I was able access the original ACS research paper (initially I'd difficulty downloading it). I've since skimmed it several times and I need to read it thoroughly to get a proper understanding but it's pretty short on the issues I've raised. Thus, my point that Spectrum should have mentioned these shortfalls still stands.
"A Recyclable Inert Inorganic Framework Assisted Solid-State Electrolyte for Long-Life Aluminum Ion Batteries", https://pubs.acs.org/doi/10.1021/acscentsci.4c01615 (Open Access)
Until we can surpass current lithium batteries in energy density, cycle stability, and safety all at once, iron-nickel is more than good enough to be used in any application where current lithium tech struggles, and will outlive you along with being infinitely recyclable and basically as safe as any battery ever could be.
They seem to cost much more per kWh than LiFePO4 batteries though.
I'm guessing the weight (energy density) issue matters for overall costs because of shipping?
Exactly the sort of thing the planned-obsolescence cartel doesn't want.
EVs in particular are entirely about batteries. The energy density of fossile fuels is the only thing going for combustion engines. Electric motors are simpler, cheaper, more efficient, more powerful, better for the environment, the only problem is storing the electricity needed to power them. Electric cars actually came before gas cars, that's 19th century tech! The only reason we are only starting to see them back on the roads is because until now, we didn't have good enough batteries.
I expect such research to pay off eventually in the same way. No big breakthrough, but maybe in the future, you will look into buying a new car and realize that that $10k electric car you thought would be useless actually has decent range, that the generator section in the hardware store has been mostly taken over by battery packs and that city buses do not sound the same as they did before.
They essentially both came about at the same time. They were both being actively developed during much of the 19th century, with the first real marketable versions of each coming in the later half of the 1880's.
https://en.m.wikipedia.org/wiki/Abundance_of_elements_in_Ear...
The cost difference (which is only 4x vs aluminum, apparently) is due to a combination of increased demand (not enough production capacity) and probably the amount of energy/environmental impact of the two processes (you have to go through a lot less ore/brine to get the aluminum).
Also, aluminum benefits from a robust recycling infrastructure that hasn’t come online for lithium yet.
Recycling lithium in the form of extracting from batteries produces a significant amount of chemical waste, meaning that the cost savings of recycling is significantly less when compared with the difference between smelting and recycling aluminum.
Even so, despite the enrichment it remains about 500 times less abundant than aluminum (in atom numbers, which matter for batteries; in weight the lighter lithium would appear even less abundant).
Moreover, the lower concentration of lithium in typical lithium ores means that for mining equal amounts of lithium and aluminum the environmental effects of mining lithium would be much worse, because more rocks are disturbed and more waste is produced.
So there is no doubt that replacing lithium with aluminum for large-scale energy storage is a more sustainable option.
https://www.barchart.com/futures/quotes/ILAM25/overview
Your graphs show it. They also show that there has not been a substantial reduction in its price over the years.
This means there is market potential for other (al/sodium) chemistries, mainly for grid-level storage.
Electric cars (by far the biggest consumer of lithium) have been experiencing a an average compounded growth of something like 50% per year for the past 10 years. Li production is still catching up. The earth has plenty of Li deposits but there is a lead time to purchase the heavy machines needed to turn those deposits into productive mines.
Once electric car growth hits the inflection point on the adoption curve, and growth becomes sub-exponential, we'll start to see major downward pressure on Li prices.
On a boat, Aluminum "corrodes" and forms an oxide layer (also known as sapphire), which then protects it from further corrosion. But, said layer is not electrically conductive (or in this case does not allow Al ions to flow into the electrolyte), so you need something to prevent the protective layer from forming.
----------------------------------------------------------------
Dear battery technology claimant,
Thank you for your submission of proposed new revolutionary battery technology. Your new technology claims to be superior to existing lithium-ion technology and is just around the corner from taking over the world. Unfortunately your technology will likely fail, because:
[ ] it is impractical to manufacture at scale.
[ ] it will be too expensive for users.
[ ] it suffers from too few recharge cycles.
[ ] it is incapable of delivering current at sufficient levels.
[ ] it lacks thermal stability at low or high temperatures.
[ ] it lacks the energy density to make it sufficiently portable.
[ ] it has too short of a lifetime.
[ ] its charge rate is too slow.
[ ] its materials are too toxic.
[ ] it is too likely to catch fire or explode.
[ ] it is too minimal of a step forward for anybody to care.
[ ] this was already done 20 years ago and didn't work then.
[ ] by this time it ships li-ion advances will match it.
[ ] your claims are lies.
----------------------------------------------------------------
Source: https://news.ycombinator.com/item?id=28025969
> [ ] it lacks the energy density to make it sufficiently portable.
... only matters for mobility applications. You can forget about this one for grid storage.
> In contrast, a typical Li-ion battery retains only 80 percent of its charge capacity after 300 to 500 cycles, depending on conditions.
LiFePO4 lasts for about 3000 cycles before 80% degradation, not 300-500.
> The batteries were also tested at temperatures as high as 200 degrees Celsius
Thermal runaway on LFP is 120C, not 200 but still not a temperature you will easily hit.
And finally (as always):
> before the Al-ion battery is ready for commercial applications, its energy density will need to be improved
Which means it's not commercially viable.
LiFePO4 is cheap to manufacture, uses lithium, iron, phosphate, all of which are fairly plentiful and lasts for over 3000 cycles (before reaching 80% capacity).
I wonder if they are quoting unrealistic 0-100% numbers and you are quoting realistic 20-80%. If so, and you multiply the Li capacity by 0.6, I wonder how far off aluminum's (undisclosed) density is.
On an unrelated note, I’m surprised that lithium is only 4x the price of aluminum. They’re both incredibly common elements, but lithium extraction is harder for a lot of reasons.
In January 2025, the North America price of lithium carbonate was $9.37/kg. But lithium carbonate is just 18.7% lithium, so the price is $50/kg of contained lithium.
In comparison, the current market price of aluminum metal is $2.62/kg. And aluminum compounds (where the large energy expenditure needed to reduce Al(+3) to the metal is not needed) should be cheaper.
Aluminum is much more common than lithium. It's the third most abundant element in the Earth's continental crust after oxygen and silicon.
This would be really useful for plugin hybrids, even if the density is not competitive with LFP for pure EVs.
Just replacing it with LiFePo batteries would give you 4x the lifetime. Of course, with current technology the battery would have to be twice the size.
Maybe, maybe not. The number that would actually matter is capacity in joules after 10,000 cycles, not the percentage.
Depends more on price than anything else. Maybe won't replace phone batteries, but a stationary battery for home or a utility-sized one that uses less temperamental chemistry would be very welcome.
picture of AA batteries
>Lithium-ion batteries like these currently dominate the market, but aluminum-based alternatives could be a better solution
There it is. No mention of how much. Though they do tell you how much longer it lasts! So apparently we aren't that averse to numbers.
* Size is important, because they need to be stored and maintained somewhere. The larger the energy storage, the more infrastructure required.
* Weight typically scales cost (the heavier it is the more it costs). If it really weighs a lot, you need to reinforce the ground too.
* Efficiency in charging and discharging. You also need to monitor the state of each cell carefully.
Li-ion capacity fall off is a fixed percentage per year, so when your car hits 80% of original capacity in ten years, its battery pack can just be used for another ten years. It’ll provide > 64% capacity at the end of that (grid workloads are less stressful than driving workloads).
So, the alternative battery technology has to cost less than the cost difference between refurbishing and recycling old car batteries. That delta might be negative.
Possible also easier recycling - especially locally close to the battery.
Even compared to LFP (much higher cycle longevity than the article quotes) these sound like they retain energy capacity much better
I can't tell if this is one of those. It does have many of the hallmarks.