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See: Some new data from research on Tesla model 3 cells Cycling within a narrow SOC range on LFP batteries can cause "reversible degradation". This is a problem because reversing this is actually quite difficult. Therefore I suggest cycling 100-0% to avoid LFP-specific quirks.

Why not 12A?

I know you are joking but space-based solar power (SBSP) may actually become a viable business in the future. Just think about how Starlink exists when it's "so much inferior" and more expensive than fiber internet.

I don't know what the point is being made from the example of Lightyear Zero when there's a realistic example on the market today, which is the solar roof on the Prius Prime. It costs $610 for a 185W panel, which is ~$3.30/W and roughly the same pricing as residential rooftop PV in the US. Yes...

Wouldn't the solar panel be underneath the tempered glass so it would essentially have similar durability? If the solar panel electronics themselves break - why do you have to replace it? If it's not worth it just leave it broken.

Drive <50 MPH. Other factors are relatively unimportant compared to your highway speed.

Model 3/Y have permanent magnet motors which have drag when unpowered. So the appearance of “coasting” actually requires power input. Therefore there’s nothing special about “coasting” in terms of driving efficiency, other than the general idea of avoiding regen braking. However this is not...

Prius Prime, Fisker Ocean, and potentially Aptera cars can have solar roofs. It generates a few miles per day in ideal conditions so it's not going to replace needing to plug in except for very rare usecases. I could see it being somewhat useful for SoCal apartment dwellers without access to...

Here is one of the EPA test cycles: they don't "turn off the car" during simulated stops/red lights, and they have no way of separately disabling the A/C, computer draw while "keeping the engine running". The EPA range figure incorporates simulated stop and go traffic. You are talking about...

It does account for all auxiliary energy while the car is running, but not drain while the car is off like sentry mode, software updates, or other wakeups. The charging losses play a factor but the main problem is the EPA highway test cycle averages <50 MPH as you can see from here: Detailed...

I've never heard of this before. Do you have a source for this claim? The language in the warranty documents is "minimum 70% retention of battery capacity over the warranty period". The language seems pretty clear and there's no mention of relative capacity or fleet average. Typically the main...

At that segment he is talking mostly about home/commercial batteries and specifically referring to his own home battery which is limited to ~95%.

It is confirmed to be a software locked LR battery Doesn't really matter going forward because the "old" RWD has been discontinued.

Then you should be fine

I am assuming you have an LFP battery. 1. 32-amps would be the most efficient because you finish charging faster and minimize the fixed overhead power draw of the car. Level 2 charging amps effect on battery degradation is negligible. 2. LFP batteries should not be charged below 32F = 0C. This...

It's better to quickly estimate degradation/current full capacity from your "Estimated miles" at 100% charge. The closer to 0% SOC the greater the error is going to be because you're dividing by a tiny number. Imagine you're at 1% SOC and it says 4 miles, or it could say 2 miles. Either you have...

Estimated miles = % SOC * EPA Range * Estimated degradation The BMS is only really in charge of estimating % SOC. Actually the estimated miles is pretty meaningless because how many actual miles you get will differ wildly based on driving conditions: flat vs hills, highway vs city etc.

First off, this is a Model 3 forum ;) The "28 kWh/100 mi" blended fuel economy figure is a weighted 55/45% mix of MPGe for city/highway driving, and is NOT the same thing as the range test. The range test involves running the car down until it stops moving with 5 different test cycles (Tesla's...

272 miles is rated by an EPA test procedure, not Tesla. The EPA test procedure used does not include parked consumption, standby or battery preconditioning. It's not clear to me that these aspects should be included in the EPA test procedure either.

Most commenters seem to have skipped over this statement. Supercharging does increase degradation of nickel-based battery packs, but not to an extreme degree. It is also mitigated because you are charging 20-50% which also reduces charging-related degradation. Usually when supercharging is...

High discharge causes voltage sag on lithium ion batteries, so if you crossed a critical voltage threshold the car might have shut down even earlier. It was good that you went slow!

Didn't you answer this questions yourself? As far as anyone knows, age is not a currently used to estimate degradation. That job is handled by the BMS measuring electrical properties of the battery. However, it is clearly ideal to anchor battery degradation on age because that is the primary...

What's the manufacturer of your solar/inverter system? If you stay within the Tesla ecosystem with a Powerwall you can simply enable this in your Tesla app. Otherwise popular manufacturers like Enphase and Solaredge have their own Level 2 chargers that can directly communicate with their...

A 50 amp receptacle and 50 amp breaker are rated and designed to handle a sustained 50 amp load infinitely without ever tripping or overheating past spec. NEC is what dictates the 80% rule for dedicated loads. As such, it is a moot point because Tesla's 14-50 adapter will not let you draw more...

Max sustained charge/discharge rate is mostly limited by the battery thermal management. The BYD blade cell dimensions are longer and narrower than the comparable CATL LFP cells, which suggests a higher surface area for heat transfer. Since both cell types use an aluminum case, it is likely the...

Based on figure 5, the recuperation by holding at 100% SOC (3.6V hold) was only able to recover <50% of the lost capacity after 35 days of continuous holding. The recuperation of 0% SOC was much more effective but is difficult to do in the real world. Unfortunately the authors glossed over the...

For LFP batteries, there is some evidence that shallow-cycling in narrow SOC ranges can cause reversible degradation. See Capacity Recovery Effect in Commercial LiFePO4 / Graphite Cells The cycling behavior that caused the most short-term/reversible degradation was the 40-60% cycling...

If your case with an LFP battery car, DoD doesn't really matter for LFP degradation. In fact a shallow DoD could have some negative effects on LFP in the form of reversible degradation due to lithium sequestration. Almost all forms of charging-related degradation doesn't really apply to LFP...

This test wouldn't be useful because the problematic aspect of BMS miscalibration comes from inaccurate coulomb counting more than inaccurately measured degradation. Degradation is predictable, but inaccurate coulomb counting is really not, and dependent on uncontrollable factors like user...

A regular house outlet 120V/15A provides 1440W. 208V/20A is 3328 W. Therefore it will charge >2.3x faster not counting passive drain, conversion efficiency or battery heating. Those factors would increase the ratio even more.

Research on LFP cells indicates that fast charging / supercharging doesn't really affect battery degradation versus charging it "slow". In fact almost all charging-related degradation is basically negligible for an LFP-based EV. This includes: fast charging, "big cycles" aka cycling between...

Yes, 25% penalty factor, driving below 60 mph on flat ground, no A/C, running until the wheels stop moving (using the entire battery buffer below 0%)

The MPGe calculations and Range calculations are not exactly the same. The range on the sticker is generally 55% city+45% highway (50-60 mph) driving mix with a penalty (adjustment factor of 30%). Meanwhile consumption (Wh/mi) does not have the adjustment factor, and yes also includes charging...

Why is this surprising? Storing the car at a constant 50% vs 100% results in a difference of 2% of capacity after 9 months (according to research charts above). We don't know the storage SOCs of the cars in this hand-picked chart, but they probably aren't at the extremes of 50% permanently vs...

If you want to replicate EPA range numbers on a Tesla, drive at 60mph or slower with no A/C. As for why Teslas have worse real-world numbers than other manufacturers, it's mainly because Tesla uses the 5-cycle EPA test procedure for EVs versus the 2-cycle test. Automakers can choose which one...

It's not that terrible because the wire is properly protected with a 30amp breaker. I imagine the 14-50 outlet is a typo because the most common generator outlet is 30 amps.

It's still pretty bad because when used as intended, PHEVs are going to experience ~0.8 FCE per day, which would be ~1500 cycles over 5 years, resulting in very significant cycling degradation. PHEV manufacturers should be using LFP batteries, but that's hard from an engineering standpoint due...

Reading carefully, the authors conclude that accelerated aging at low SOC is due to SiOx degradation It is known that silicon doping of the graphite anode can increase energy density and increase charge/discharge rate, however silicon doped anodes also have faster degradation compared to pure...

There is some evidence that exclusive shallow discharges within limited SoC levels can cause reversible degradation due to "uneven storage" of lithium. Reversing this effect requires extended full charge/discharge. Since LFP batteries are not affected by DOD for permanent degradation, my...

It's probably CATL's "M3P" LMFP batteries. It's made in China, energy density/range slots in right between the RWD LFP and previous LR, timeline matches up, and the "325+ range" figure hints that final performance testing has yet to finished. If Tesla is using cells already being used in China...

To break it down: 7.8% calendar aging * 1.6% cycle aging = 9.27% net degradation. Cars with 2021 model year and 60k km, degradation will by dominated by calendar aging. Even if we improved cycle aging by 20%, and cut down cycle aging to 1.3%, then the net degradation would be 7.8% * 1.3% = 9.1%...

Think of this extreme thought experiment: You have a (non-EV) battery at 100% charge, every day you consume 20% charge and recharge 19%. You repeat this process until one day you start with 20% charge and use it down to 0% charge. Is this situation more similar to 1 full cycle equivalent (FCE)...

Lithium batteries used in EVs seem to have less degradation than batteries tested in the lab with continuous charge-discharge cycling, even temperature-controlled and comparing the same number of equivalent full cycles. I think this is likely due to regen braking breaking up the discharge...

Just a reminder that the "degradation" from charging in a narrow voltage band as shown in the chart is not real degradation. It recovers when you start charging a wider range of levels. Of course, cumulative charging cycles and a high resting/average SOC will still cause real degradation.

Please see this video Lower voltage is part of the reason. The other part is the crystal structure of LFP vs ternary. The olivine crystal structure of LFP lowers the diffusion rate of lithium ions but also increases stability. One you understand the crystal structure, many of LFP's...

Lithium plating specifically happens near and below freezing temperatures. A 50F=10C "it's cold" day poses no risk of lithium plating so there's no justification whatsoever of preconditioning "to protect the battery". At freezing temps, your power will be limited both acceleration *and* regen...

Tesla is upset at you for not charging your LFP vehicle to 100% recently and forcibly overrode your charge limit.

That's still how they work. There isn't circuitry to actively balance individual cells. Balancing at 100% isn't a rumor - it's absolutely true but probably not necessary for most folks. If there were imbalanced strings of LFP due to individual degraded cells, "accelerated degradation" would be...

Either set charge level at 50% plugged in, or charge up to 100% and run it down as low as you're comfortable with before charging to 100% again (like a gas car). Lots of people on here will say: "just charge to 100% everyday - who cares if there's 5% extra battery degradation after 5 years...

A/C draws like 5kW max, but probably less (1-3kW) in the steady state, so nothing like 100mph but still significant. Regardless, any energy usage (like speedy driving, A/C) hammers EV range more than ICE simply because the total amount of energy in a tank of gas is so much greater than an EV...