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Tesla Batteries Retain Over 90 Percent Charging Power After 160,000 Miles, Survey Finds (engadget.com)
According to a survey of over 350 Tesla owners, Tesla batteries retain over 90 percent of their charging power after 160,000 miles. The EVs dropped only 5 percent of their capacity after 50,000 miles, but lose it at a much slower rate after that. Most Tesla vehicles will have over 90 percent of their charging power after around 185,000 miles, and 80 percent capacity after 500,000. Engadget reports: Tesla has no battery degradation warranty on its Model S and X luxury EVs, but guarantees that the Model 3 will retain 70 percent battery capacity after 120,000 miles (long-range battery) and 100,000 miles (shorter-range battery). That's a bit more generous than the one Nissan offers on the Leaf (66 percent over 100,000 miles) for instance. According to the survey data, Tesla will easily be able to meet this mark.
This 'survery' was basically a collection of message board posts. 350 respondents, but the article doesn't say how respondents reported results with so many miles. I looked at the first few pages of respondents and none reported having driven near 100K miles yet. So I assume the actual sample of high mileage owners was quite small. Too bad the author neglected that obviously important info.
Of course, that will void all the billion dollar options and package he has now, but he does not care much about money personally. So that is not a problem. But he has so much ego and would not like the shorts to win either. That is his dilemma.
He needlessly limited his options, by responding to Economist and Bloomberg, saying categorically he is not going to seek financing etc. He should have thrown in some weasel words in there.
But, in the end, Space X is very good shape, it is likely to land some really big defence contracts and communication satellite launches. So like he used Tesla to rescue Solar City, he will use SpaceX to rescue Tesla. By the time Tesla rescue package bill comes due, Tesla is likely to be in a much better shape and will weather the storm.
If it is not SpaceX, he can tap the Japanese bond market through the battery making partner Panasonic. Or he can sell out to the devil and bring China in and they would gladly retire the Solar City rescue package debt for a decent chunk of Tesla and access to its AI experts. So my personal hunch is the shorts are going to escape with just some minor losses, suing for a draw.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Teslas don't work in the winter, they are too expensive and nobody buys them, there is no way to charge them on any sort of reasonable road trip, they won't work for me because I commute 500 miles every day, and they're just propped up by the government anyway. Add to this that they can't manufacture them in volume, they will run out of batteries, they'll run out of the raw materials for the batteries, and nobody wants them anyway, and look at all the recalls!
My ICE doesn't drop down to 90% capacity after 160,000 miles. This is just proof that Tesla will never be successful, and there's no reason for us to keep talking about them.
Tesla. Is. Dead.
(Did I hit all of the hater points, or did I miss one or two?)
Velociraptor = Distiraptor / Timeraptor
This 'survery' was basically a collection of message board posts. 350 respondents, but the article doesn't say how respondents reported results with so many miles. I looked at the first few pages of respondents and none reported having driven near 100K miles yet. So I assume the actual sample of high mileage owners was quite small. Too bad the author neglected that obviously important info.
OK, here is the actual data if anyone is interested;
https://docs.google.com/spread...
Laptop batteries are kept fully charged, right next to the hottest components in the system.
It's like they are designed to degrade the life of the high margin consumable part of the product you can usually only buy from the manufacturer due to its proprietary design..
Indeed. A few other things:
* For a vehicle with a range of, say, 250 miles, where the driver drives, say, 25 miles per day, is only using 1/10th of a cycle per day.
* Few owners charge to 100% daily. Most set a limit in the 60-90% range, with 70% and 80% being common. So not only are they doing shallow cycles, but they're doing shallow cycles in a near-optimal-for-longevity portion of the pack.
* Unlike laptop batteries, which are often just cells in series and thus limited by the weakest cell, Tesla packs have many dozen cells in parallel forming bricks, which are then linked in series (these in turn are linked in parallel). A failure in an individual cell has an insignificant impact on the whole.
In short, you have shallow cycles, in a gentle portion of the charge curve, with a chemistry specifically designed for long life, a failure-resistant architecture, and climate controlled to optimal operating conditions. You get what you design for. A cell phone and a laptop, by contrast, design for low unit cost and high energy density. Tesla packs are only 150-180Wh/kg, whereas you might get over 240Wh/kg in a cell phone battery. But cell phones and laptops are only designing for a couple year lifespan, with deeper cycles every day, no redundancy, no climate control, etc
No matter how kind you are, German children are kinder.
I doubt you would even get close, realistically, for two reasons:
A bicycle is not likely to do either of those things. It probably isn't even physically possible to usefully put a heat pump into something the size of a bicycle—a motorcycle, maybe, but not a bicycle.
Check out my sci-fi/humor trilogy at PatriotsBooks.
1) Laptop batteries are designed for energy density, not longevity. There are tradeoffs in chemistry selection.
2) They're not climate controlled. Just the opposite, they're right next to a source of heat.
3) They go through deeper cycles, over a wider portion of the SoC range.
4) They have no redundancy / cell bypass
5) They're designed for a product with a pre-determined expected lifespan of only a few years, so they have no incentive to do better.
You can design to any spec, if you're willing to accept the tradeoffs.
No matter how kind you are, German children are kinder.
Tesla batteries last in part because of the advanced temperature control. They are kept warm in the winter, and cooled when you are flooring it, hot lithium batteries don't last long and cold ones don't perform well till they warm up. That's why the leaf is bad in some situations as a very cold or hot pack hurts performance and lifetime accordingly. A second strategy is to not fully charge or discharge them, using only a fraction of the battery pack capacity. This also extends life quite a bit and is used by virtually all electric car manufacturers. Here is a good article on a particular cell the tesla uses. Tesla, like several others, use cells that are more robust to abuse with a long life at the expense of actual capacity at high discharge rates, but it's a good tradeoff price wise even though the cells are more expansive. Not covered here is the long term stability of the cells as not a function of cycles but one of cycles and time. Just like any battery they age even if not used. You may get a whopping 35 thousand charges if you go from 80% to 20% capacity but that's not the case if you wait 10 years and store the battery properly. So take this article with a grain of salt because it does not have an actual time component other than couple of years it takes to get the data. These cells haven't been around 20 years so one needs to extrapolate and guess as to the actual long term viability.
My Subaru gas tank developed a rust through hole on the side wall of the gas tank at around 109K miles. It lost more than 80% of capacity.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Gee, I can't imagine why owners would want to collect data to determine how long they can expect their batteries to last. It's just beyond comprehension.
No matter how kind you are, German children are kinder.