Battery Design and Info

[curtis-cibinel]

Aptera 45kwh is designed using NMC 811 2170 cells from EVE; LFP was not adequate for anything past the 250 mile Aptera in 2019 but it has evolved. The larger Aptera packs (600/1000) have been said to use larger form factors which could be 4680 or 2665. LFP could definitely be a viable option for Aptera but was not when development started. Modern LFP and LFMP chemistries are pushing above 200 wh/kg which is definitely viable for ranges up to 600 miles. Aptera currently needs to focus on getting the current design refined and into production. I suspect at minimum the 250 and 400 will switch within the first 1-2 years of production. LFP chemistries could potentially save $1000-3000 per vehicle which is critical profit margin. Assuming 2c discharge LFP could end up slightly power limiting the 400 mile vehicle so 0-60 times could be hurt a little (and the 250 would be substantially power limited with only 46KW / 150KW peak for AWD).

On the charging front LFP and NMC cells typically have rated max C rates for charging of 2C. Tesla charges at a peak of 4.5C with DCFC with substantially more cooling and packs approximately equal to the 600 mile Aptera. It is possible if the Aptera cooling can keep up larger packs MIGHT be able to charge faster than 50KW (assuming all components could handle it). LFP might impact charge rates.

[Greek]

Here’s some common Evs and their winter loss stats.

D82B418E-2D01-4196-B518-8A19B5BA6882.png 1 MB Image File - Click to view

• Copy Download Link

[david-marlow]

There are a lot of things about winter driving that will reduce range in any vehicle, however in EV’s the greatest is how you use the electric cabin heater. My experirnce in my Volt tells me this.

[Highpockets]

Tesla’s early design resulted in battery damage (and fires) from belly pan damage when encountering road hazards. The Delta design has an aluminum belly pan. Heat transfer is enhanced, but road hazards such as truck tire treads may cause severe damage to aluminum. What is Aptera’s answer to this problem?

[993cc]

My understanding is that the alumin(i)um belly pan will not be in contact with the battery pack. There is some crush space between them.

[FoggyOptic]

If it wasn’t the 100kwh design, then I’m starting to question whether the promise of a 1,000-mile range capability is anything but vaporware.

[993cc]

It will be 42 kWh/400 miles for the launch edition, I think.

The 1000 mile version may very well require advancements in battery energy density beyond what is currently available, which is probably why it will be the last to be released.

It almost certainly isn’t possible with the cells they are using for the Launch Edition, but advancements occur daily.

[FoggyOptic]

That’s kind of what I was looking at with the render video. It’s simply a matter of energy density. If the form factor they used for the render is representative of the 42kwh pack then I’m starting to question whether there is physical space available for a pack roughly 2.5x the size.

[david-marlow]

I know that different batteries have different rates of charging efficency.

Too slow or too fast are not as good as the sweet spot in the middle.

Evendently Aptera has looked at that and with all things concidered, found that the level 2 charging will be best, as their main direction is towards efficency.

[john-malcom]

I think Aptera stopped working on maturing the development of DCFC for cost, weight, schedule and Perhaps because of the adoption of the Tesla plug, not because Level 2 is a sweet spot. As indicated by the response of the market, DCFC is a essential feature of EV’s for road trips regardless of the effect on battery health. Level 2 is harmful for battery health if constantly charge from a very low state to full charge.

[kerbe2705]

@David Marlow IMHO this isn’t about “battery efficiency”, it’s about the fact that DCFC makes batteries HOT and, when it’s not moving, Aptera has no way of shedding excess heat. In the past they’ve mentioned the need to develop a system to cool the pack while charging and I’m guessing they haven’t yet come up with one that works sufficiently.

Remember, they’re still hoping that “belly cooling” will work: They haven’t yet tried it on an actual vehicle…

[david-marlow]

Heat represents ineficency, however there is a lot that goes into measuring efficency, getting energy into and out of a battery can have different efficency rates. Also the efficency of the charging and discharging circuits also play a part.

[richard-palmisano]

This is not going to sit well with some…

Ok, the launch event had the glaring elephant in the room: No DCFC. That was a complete swing and a miss. Fortunately, they listen. The Forum, the community, the investors all literally had bile in their mouths at that news and voiced their opinions, apparently very loudly, that this was unacceptable. How could they not have seen this?

So it begs the question: Is Apteras focus on Battery and Thermal Management Planning, the MOST IMPORTANT ASPECT of an EV, not on par with other manufacturers?

It makes sense for a 40kwh(ish) pack to be able to recover half charge in less than an hour, IMHO. So the DCFC system should ALWAYS have been in the crosshairs for 50kw of DCFC, so that when you go from say 20%-80% you can achieve this in about 45 minutes. I, as well as most EV enthusiasts, find this acceptable. It’s still not world class, but highly acceptable to get 200+ miles of range in one fast charging session.

Is Aptera’s Thermal Management an issue? Can they get the cooling they claim from the belly of the vehicle? It always seemed to be a complex idea, having cooling in the body. Seems like a recipe for disaster honestly.

If they had the system already, 40-60kw DC charging, but decided against it for complexity reasons, how then can they add it without complexity? Without better thermal management? There seems to be some explaining to do and honestly, I don’t think they can…at least yet. They need to get into production. They were willing to produce the vehicle without DCFC and tell you, “most won’t likely need it”, which they found out quickly that MOST DO! This is a little disturbing.

I would like to know how they could prepare a launch without DCFC, and then turn 180 a few days later? THIS IS YOUR PRODUCT LAUNCH! This is where you say, here it is! Oh wait, you wanted what??? DC charging??? We didn’t think of that.

Scary bad…just not good.

• This reply was modified 4 months, 1 week ago by  Richard Palmisano.
• This reply was modified 4 months ago by  Gabriel Kemeny.

[jesthorbjorn]

I wish they would have come right out and said in the back-peddle video that they already have the battery thermal management to handle DCFC incorporated since that was the dominant assumed deficiency that folks were attributing the lack of DCFC to. Instead they divert us to thinking of the paused PDU development without mentioning thermal management. I’d like to think of this as engineers ignoring irrelevancies and getting to the root of the issue. Still feels a bit like political re-direction to avoid an uncomfortable answer to the real question.

Still it is obvious they got the message and I guess we will see how it all shakes out.

• This reply was modified 4 months, 1 week ago by  Joel Smith.
• This reply was modified 4 months ago by  Gabriel Kemeny.

[david-marlow]

While 98% of the time I won’t need fast charging, I do want to have it available for long trips. I realise that using fast charging reduces the life of the batteries.

Any heating of the batteries reduces their life, especialy at or near full charge and fast charging creates much more heat in the cells than level 2 charging.

[Pragmatic_to_a_Fault]

I’m wondering about the constant solar charging and the degradation of the batteries, constantly topping off a lithium battery is bad for it no ?

I was told and have read that if you drain your phone down for instance to 75% and then fully charge it , that the batteries now think 75% is zero anymore only hold a charge down to 75% and then require recharging every time.

https://news.ucr.edu/articles/2020/03/11/fast-charging-damages-electric-car-batteries

[barry-jewett]

Is it possible that there was an underlying issue that needed this sort of “Webinar” presentation, to make a clear point? Something just feels off. We all have responded for them to clarify a point.

For what?

For who?…

• This reply was modified 4 months ago by  Barry Jewett.
• This reply was modified 4 months ago by  Gabriel Kemeny.

[Biker]

At about 2:20 in this video, Chris Anthony provides answers to some of the issues raised by Richard:

Aptera CEO Chris Anthony Talks Launch Edition with DC Fast Charging – YouTube

[daniel-crotty]

I just (Mar23) watched a Video from Sandy Munro

BREAKING NEWS: Amprius Creates a 500Wh/kg Battery – YouTube

From what I see, this is “a really big deal” and doubles the battery metrics. So, my 400mile range car becomes an 800+ range car, the + is because of less battery weighs.

😃 A 2K+ range EV! Match that, competitors!

I’m obviously guessing on that. I do not claim to know or understand all the facts and issues.

When will it be available, cooling, cost, weight, etc.

Is Aptera locked-in to a supplier?

Can the supplier deliver a shape and size we can use and not have to re-design the body.

I know they signed with a battery company, but,,,! More efficiency! That is what Aptera is all about.

At a minimum, this sounds like something to look into.

[Mike-Mars]

> When will it be available, cooling, cost, weight, etc.

Probably a few years – 5 at the earliest maybe?
The weight is 0.5kWh per kg if I recall correctly (and 1.3kWh per litre, which is pretty impressive), so you can just calculate it based on the size of the battery.

I doubt that they’ll aim for a 2k mile vehicle, they’d probably want to half the weight of the 1000 mile battery instead, which would improve the efficiency (particularly in stop/go town traffic).

> “Can the supplier deliver a shape and size we can use and not have to re-design the body.”

The battery cell size for the 600 and 1000 will be different in any case. So it’s not a big deal as far as new vehicles are concerned. However it becomes important when retrofitting a replacement battery. They could probably make the cells in any size, but from a cost/benefit viewpoint they’d probably want to limit the number of sizes that they produce, until volume production is sufficiently high.

> “I know they signed with a battery company, but,,,! More efficiency! That is what Aptera is all about.”

They’re already signed up with two suppliers. Eve energy for the initial 2170 cells for the 400 mile battery, and Formosa AdvEnergy Technology Corp for the future.

• This reply was modified 2 months, 1 week ago by  Michael Marsden.
• This reply was modified 2 months, 1 week ago by  Michael Marsden.
• This reply was modified 2 months, 1 week ago by  Michael Marsden.

[curtis-cibinel]

These cells will could be a super valuable commodity and are best suited to drones or aviation (maybe supercars). Aptera is trying to be cost effective and these cells will be prohibitively expensive initially (think 10+ times the price). Aptera could potentially use sodium cells which are even cheaper than LFP and still hit 400 miles – no need for the industry best cells when the worst is viable. Sodium is safe, cheap and good with temperature ranges but its energy density (especially volume) is too poor for most EVs

[john-locke]

At some point you have to freeze your design and make it manufacturable. There will always be something better “available soon”. The 400 mi battery will be adequate for 90% of users. When you add solar charging to the mix, the usable range for daily drivers is closer to 900 mi. That’s if you drive 16000 mi/yr. You might charge overnight a couple of times a month. DCFC is only needed for long distance trips of more than 300 mi. and not many people are willing to drive more than 5-6 hours straight anyway. Faster charging is always more desirable but 30-45 minutes should be adequate. 50KW will do although 100KW would allow 15-20 min. full charges. That would require more cooling for the batteries and 3C charge rates. The batteries are probably able to do that but it’s less desirable and will stress the batteries somewhat.

[glen-flint]

Will these batteries be available by the time the 1000-mile range Aptera is in production?

World’s largest battery maker announces major breakthrough in energy density (thedriven.io)

[Jeff]

No word on pricing, cycle life, etc.

Also, isn’t Aptera using cylindrical cells? Swapping those for a pouch cells just for the 1000-mile version and having a totally different battery pack architecture likely wouldn’t make sense.

[david-marlow]

Since the 1000 mile version will not be built for at least 3 more years a lot in the battery industry will be changing by then, so what will the batteries Aptera will be using by then?

The only thing that Aptera has promised is that depending on the size/range that you purchase, that you will be able fit in an upgraded battery of at least similar range. If the new batteries at that time are significantly different, than the BMS will need to be changed as well.

Since the packs that they currently have designed are expected to last at least 8 years and I don’t expect the cost to decrease by more than 80% by then, why would we want to replace them sooner?

[john-malcom]

A lot of unsubstantiated speculation here. All indications are (But not confirmed) that the battery warranty will be 10 years not eight. We don’t know what the timeframe for building the 1,000-mile variant of the Aptera will be at this point. Perhaps even Aptera does not know with all the “Moving parts” of the current situation. We do know that the batteries for the longer-range versions of the Aptera will most likely be different from the 2170 batteries for the 400 and possibly 250-mile variant. We certainly do not know if any emerging battery technology will be considered for any variant of the Aptera post LE launch. Factors that may negate adopting new battery technology would be the reengineering required, changes in the logistics chain needed to support the reengineering, and the changes in production operations to incorporate a battery change. All impacting budget and most likely resulting in variant release delays and perhaps moving the work for the next type of Aptera (Four wheel, more than two passengers; EU compliant version)

[john-malcom]

👍😄

[Greek]

Although all you have posted John M is always educating me, not sure we should be patting ourselves on the back😉.

Aren’t we getting ahead of ourselves with the final proposed variant of the APTERA? I am so stoked to someday (hopefully soon) to receive the first variant.

Also may need to consider the European version that still needs funding for redesign. Time and resources will need to be allocated which takes away from future long range iterations. From what I have learned thus far about automotive start ups (especially electric vehicles), we need to get the 1st iteration out to the public and worry about future products after the fact. What good is it to worry about 1k model without even having an LE test mule?

[john-malcom]

Good point! Anything past a focus on getting LE into production as soon as possible is a waste of mental cycles. I have fallen pray to my most egregious fault, speculation that divers attention and focus from the most important thing, getting To production soonest. 🤐 All else is moot at this point. Appropriate to call me fox task on this. I will try to do better.

• This reply was modified 1 week ago by  John Malcom. Reason: Added idea

[Greek]

Nothing but respect for you here John, I love the education you bring to this forum. Please continue your diligence.😊

[ROMAD]

Greek, if you look closely, John is giving a 👍 to JEFF’s post, not his own.

[Greek]

Thanks Roman, using my phone to communicate. Didn’t follow the timeline, unlike John to toot his own horn……My apologies to John Malcom.