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Comment by rmbyrro | Hacker News Reader

In ~3 years it lost only 8.7% of battery capacity, looks good. I wonder whether capacity loss accelerates with time or it's linear.

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Degradation is nonlinear and front-loaded. Expect to lose 5% by 25K miles, another 5% off the top by 125K miles, and then the final 5% no sooner than 200K miles (data is sparse after that). https://insideevs.com/news/525820/tesla-battery-capacity-ret...

That just about lines up with our experience. Our 2014 S 85 has about 200k miles and we're sitting at 13.5% degradation. 230 miles vs. the 265 it was rated new.

It's not as simple as that.

"keep in mind that time, temperatures and other factors (like how long the battery stayed at a high state-of-charge levels) also influence the battery degradation."

I have yet to even put 25K on my Model3, but I have already lost 9% in my 3.5 years of ownership.

Right battery degradation over time is also a serious consideration and why I'm still in the "buy max range" camp. I've lost 9.5% range in 3.5 years. So you need to multiply all these factors out. Rated Range x Battery aging x weather impact x speed impact x % charge

So for example on a 310mi rated Model 3 after 4 years, taking a 75mph highway road trip in winter it might look like

310mi x 0.9 battery age x 0.9 weather x 0.8 speed x 0.9 charge % = 180mi..

This roughly checks out with some of my Christmas road tripping recently. Another reason I'm never buying a "240mi-ish" EV and target buying something closer to 400mi than 300mi, and only with access to a huge charging network like Tesla in 2022.

> and only with access to a huge charging network like Tesla in 2022.

There are a lot more non-Tesla chargers than Tesla Superchargers.

Though they're slower and more expensive.

Whoever decided 7.2 kW J-1772 chargers should exist needs to be dragged out back and shot. They did a lot of damage to EV adoption by feeding the notion that EVs take several hours to charge. Chargers below 150 kW shouldn't exist, IMO.

Yup, our 2018 Model 3 LR with 60k miles on the clock can charge currently claims it can charge to 296 at 100%, but I don't think I've seen over 284 recently. I have no idea what it was when new. 300 maybe? 306 sticks in my head? But then at some point they "unlocked" more range and said it was either 315 or 325, but I can't remember. I do remember for a fact the most I've seen on a 100% charge was 314mi, but that was after 6+mo of ownership so it wasn't a new pack at the time.

The Capacity variable when looking at the calculus of EV's sucks, quite frankly. On a depreciating asset (supply chain/covid issues notwithstanding) (vehicle)) you are buying something that degrades and depreciates the entire purpose of the asset in the first place. TCO factoring in loss of range over time is probably something you just have to ignore if you really want to buy an EV. Otherwise, most people would just buy a Prius or a Corvette.

Offset by the fact that you get many of the good properties of a Prius and a Corvette at once, and don't pay for gasoline or oil changes. (electricity is generally an order of magnitude cheaper)

As well, anyone buying an EV today, should the worst happen and they need a new battery after ~8 year warranty, the prices of batteries has been steadily dropping.

> electricity is generally an order of magnitude cheaper

Electricity is not an order of magnitude cheaper.

You can figure on getting about 4 miles per kWh. Where I live, the kWh delivered is $0.20, so $0.05 per mile for energy.

A gas car getting 25 miles per gallon with a gallon costing $4.00/gal (slightly more than it costs around here) costs $0.08 per mile for energy.

If you could buy electricity for half of my price, you'd be $0.025 per mile, meaning a 25mpg car would need to be buying $6/gal gas in order for electricity to be an order of magnitude cheaper.

Where I live, gas is $1.56/L and electricity is around 11¢/kWh.

So assuming 6km/kWh and 100km/9.5L, the difference is a factor of 8. Also, my car is not nearly this fuel-efficient—I get about 14L/100km.

I assume you made those prices up as unrealistic, but it just depends on where you live.

Going by the prices you listed, I assume you are also from quebec ? Keep in mind gas prices in parts of the US are much lower than ours, and 14L/100km sounds like a lot for a sedan (which is the type of vehicule that gets 6km/kwh). So I don't think their figure is that unrealistic for the average North American use case, and you have to factor in the fact that we just have exceptionally cheap electricity too.

For what it's worth, energy prices in kentucky have us paying on average 9 cents per kilowatt. That gets you within striking distance of an order of magnitude. It's a significant savings either way.

Gasoline is only going to get more expensive. Electricity _might_ get cheaper

We’re only .12ish per kWh in Florida but they have an time based plan where I can get .08 off peak hours which would be ideal for an electric.

(I may have the math wrong it’s kind of confusing … https://www.fpl.com/content/dam/fpl/us/en/rates/pdf/res-jan-...)

Don't feel bad-- it's incredibly confusing. We have solar, and I have no idea what we actually "pay". We over-generate in the summer months but re-use those credits at a different value over less-sunny months.

But the kicker is, in the winter, production is so low that even our off-peak charging hits tier 2 so the rates are thrown all out of whack.

It's probably actually cheaper to charge our car at a supercharger in november/december/january than to charge at home, tbh.

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