Tesla Batteries Retain Over 90 Percent Charging Power After 160,000 Miles, Survey Finds (engadget.com) 188
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.
Too expensive (Score:2)
I'd like to see the results of Tesla's amazing battery tech on electric bicycles.
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80% capacity after 500k miles is pretty good if it’s true. Currently, the condition and remaining life of the - expensive - battery is a big worry for buyers in the second hand EV market. It would be great if that’s shown to be a non issue.
Re:Too expensive (Score:5, Informative)
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.
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The Tesla batter will also play games much like modern cell phones. They will only charge to 80% and never discharge below 30%. Applying this technique in cell phones is what allowed Apple to integrate a non-replaceable battery that would get 1000 charge cycles. Previous phones would only get ~100.
Electric bikes want to maximize their range so they probably go from 0 to 100% when charging / discharging. Most battery powered electric tools do the same thing --- working time is more important then the
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I was referring to the pack balancing circuitry. Why would that be useless on a bicycle?
Re:Too expensive (Score:5, Interesting)
Re:Too expensive (Score:5, Informative)
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... [google.com]
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Moreover, they are reporting what the car tells them is the remaining battery capacity. Unlike Lead Acid batteries, it is apparently difficult/impossible to determine charge state of Lithium ion batteries from the battery voltage except near full charge and near empty. Since EV owners presumably avoid low charge states. there's little or no opportunity for the computer to recalibrate capacity based on actual battery charge level information.
The vehicle computers could be a lot more honest than than those
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If you're just having a once-off voltage sample only, then yes, predicting the current % capacity of a lithium pack is quite tricky given their fairly flat discharge curve and the fact that depending on what load you're imposing the voltage swings a fair bit depending on the pack internal resistance; however, in its place we use coulomb counting, with coulomb counting you're measuring the energy being put in and taken out, and as such you can track with a far greater level of predictability.
Here's a quick s
Re:Too expensive (Score:4)
The bigger problem is that there are four different batteries represented here: the 75kW, 85kW, 90kW, and 100 kW packs. And that's not even counting all of the silent upgrades to those batteries over time. From what I've read on the various Tesla-related forums, the early 90kW batteries lose their capacity much faster than other models.
By combining every pack version into a single number, it masks any design flaws in any single model of pack, resulting an average that doesn't reflect anyone's actual experience [xkcd.com]; if the 90D packs really are significantly worse than average, then for most users, the experience will be much better than these numbers suggest, and for those unlucky few, the experience will likely be much worse.
A more useful way to summarize this data would be something more like "X% of 90D battery packs were projected to have 90% of their life or more at XXX,000 miles." at several different mileages.
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Yikes. Not sure how I made that mistake once, much less five times.
*hangs head in shame*
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If the average Model S was only getting 120 miles out of a full charge, there would be hundreds of Tesla every day that needed towing.
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That seems like a reasonable number to me. If the manufacturer quoted range is 300 miles, you can bet that is under ideal conditions i.e. on a flat route with no heavy acceleration or deceleration and with the air conditioning turned off. Also, if you know you will only be doing 100 miles in a day, you might drive a bit harder, reducing the range still further.
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the range on Tesla vehicles is certified by the EPA. Testing consists of both highway and city duty cycles, and is intended to simulate real-world conditions -- their cars go through the same process that internal combustion engine cars go through for their MPG estimates.
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"I'd like to see the results of Tesla's amazing battery tech on electric bicycles."
I'd like to see you drive 500.000 miles with that bike.
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There is still one original washer on the seat clamp assembly,
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Some of it already is. The trick to maximizing battery longevity ( not vehicle range ) is to charge slowly and not charge or discharge too much. The OTA update that let Florida owners have an extended range to evacuate ahead of a hurricane was an example of relaxing that discharge amount temporarily. If use only 60-80% of a battery packs actual capacity it will live longer.
There are electric bicycle chargers that do this, charging at a lower rate and to a lower voltage to extend the battery's life. Som
How are their batteries so much better than laptop (Score:2)
batteries? I have a pile of Dell Latitude batteries on my desk for laptops mostly between eighteen months and two years old that I need to distribute. We've recently been buying Dell Precision laptops since they have internal batteries that don't have the problems removable batteries have. Too many of our users have laptops shutoff when they're walking into conference rooms. It sucks having to wait on people running meetings that take 5+ minutes for Windows to reboot while you're waiting on them to scre
Re:How are their batteries so much better than lap (Score:5, Informative)
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.
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Some laptop manufacturers are a bit crap.
I finally abandoned my eee 900 after a decade of use. It was still getting about an hour of charge on the original battery (down from 3.5 hrs). Not bad for 10 years old. My current W510 rocking in at 8 years old, well, that battery was never long lasting in the first place, barely an hour (IIRC, maybe less!), and is now measured at about 10 minutes.
I get some degradation due to the properties you listed, but 5 minutes of use after 2-3 years is really terrible.
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Musk's dilemma.... (Score:5, Interesting)
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.
Re:Musk's dilemma.... (Score:5, Interesting)
Indeed. There's so many funding sources it's not even funny (even the short-selling echo chamber over at Seeking Alpha [seekingalpha.com] has covered this). And they didn't even get into the Musk aspect like you did. He's already demonstrated that he's more than willing to use some of his companies to bail out others, and that other stakeholders in his companies are - despite some grumbling dissenters - more than willing to let him. SpaceX is on a roll - they'll probably have half of the global launch market this year. Russia has basically thrown in the towel. SpaceX just got a 500M investment at a $24B valuation, and there's tons more investors wanting a piece of it who can't get one. If Tesla needed it, who wants to wager a bet that SpaceX doesn't suddenly decide that it wants to preorder a ton of semis for hauling rockets, preorder a gigacharger network along their route, order some powerpack buffers for their liquid oxygen plants, offload (at contracting rates) engineering work to Tesla, etc, if not outright buy part of the company? To say nothing of Musk's other ventures. At some point, for example, Boring Company is going to need to do a fundraising round in order to pay someone who engineer and build the Loop vehicles. Gee, what company do you think they might pay to do that?
Beyond the cash issue, the short selling thesis is fatally flawed because of numerous wrong assumptions, such as "Model 3 production will only be 2500-3500/wk at the end of the year", "SG&A will remain at a constant ratio with automotive gross profits", and "There's serious competition on the near horizon". All three of these premises are nonsense; for each of them, I understand their logic train, but it derailed a couple stops ago. They also ignore the growth potential of Tesla's other divisions (although, sure, they're not going to carry Tesla on their own).
Re:Musk's dilemma.... (Score:5, Informative)
I saw one article (I can't find it now -- perhaps it has been pulled), that attempted to compare ICE cars and Tesla cars, specifically the Model 3. It claimed that the Model 3 had a big drawback that would have to buy a new battery in 20 years time. Guess what you call most ICE cars when they are 20 years old? Mostly: recycled metal and other materials. The basis for the new battery claim ignored published data on the life of batteries, choosing instead to substitute some numbers the author had pulled out of one of his orifices.
The article also chose to arbitrarily increase the cost of batteries from what they are today, instead of assuming that battery prices would continue to drop.
I am convinced that some big short sellers are paying for a disinformation campaign, to force Tesla stock down.
What you call an ICE car when over 20 years old (Score:3)
My "daily driver", you insensitive clod!
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The battery is actually a big asset. When the car is recycled or the battery does reach end of its useful life for propulsion, it can be sold off for use in less demanding applications like home battery packs, UPS systems, utility level smoothing etc. Or even just passed on to someone who can live with 150 mile range, which it turns out is an awful lot of people.
Re:Musk's dilemma.... (Score:4, Informative)
Apparently you stopped reading before "the short selling thesis is fatally flawed because of numerous wrong assumptions"
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Meh, to me it looks like a lot of exaggerated drama. Tesla got >3 billion on hand and can burn money at their current rate for well over a year. Meanwhile they've had a massive facility ramp-up. Bloomberg estimates they now produce 2733 [bloomberg.com] Model 3s a week, if they can hit their 5k/week end of quarter goal all those shorting will be crying. Either way I think this more for investors and how good ROI they're getting, not that Tesla is going anywhere...
Re:Musk's dilemma.... (Score:4, Informative)
Nah, the shorts will first try to claim it's a burst rate. After a few weeks they'll start switching their attacks to "Tesla can't be profitable." Once Tesla turns a profit they'll switch it to "It's a one-time thing, but doom is just around the corner. DOOOOM!!!"
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The big hedge funds will move on. But the small time shorts that lost money will stay on the sidelines and egg on the next batch of shorts "go ahead, *this* time it will be different".
In each iteration their numbers will shrink and they will be reduced to bad mouthing Tesla in Seeking Alpha and in sub reddits.
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SpaceX has big capital intensive plans of its own, and may not be available to bail out Tesla. Not only is SpaceX building the BFR, but they're also planning to build and launch at least 2200 of their own satellites [wikipedia.org] at 400kg each.
Bare in mind that Musk really really does not want to take SpaceX public. He wants to take SpaceX to Mars, which can't be justified in dollars, so couldn't happen if SpaceX were public.
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Musk is not writing off 1.5 billion from SpaceX. He is just rearranging the cash flow. In his mind, Tesla is not writing off the Solar city bonds. He believes all the companies will succeed, and all that is going on is simple rearrangement of cash flow.
So he will n
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Unlike my Apple laptop (Score:2)
Which lasts about 18 minutes after two years of charge-discharge cycles.
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Really? The 2015 MacBook Pro I got for work in Spring 2016 can still go 8+ hours - I’ve recently taken it through a full work day on battery as a test of the estimates it provided (until I upgraded from El Capitan - High Sierra doesn’t provide those estimates).
I admit I rarely fully discharge it though; usually the furthest I take it is to 50-60%. But over the years I’ve had consistently good battery experiences with Mac laptops... excepting perhaps the second-generation Air whose battery
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Mine sits on my desk charging about 99% of the time. I usually don't realize how short the battery life has gotten until I that rare occasion when I need a laptop in a meeting. Replacing the battery made all the difference, and I'll see if in another year or two if the problem repeats itself.
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And if I said it was a Dell laptop you wouldn't have said a word.
I think it's interesting that a Tesla doesn't need a new battery, but a laptop does.
Tesla is Done (Score:5, Funny)
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?)
Re:Tesla is Done (Score:5, Funny)
And we all will sorely miss matching our wits against the dealership salesdroid. I love doing research on Truecar, Vehix.com Edmunds and Costo.....
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And the fit and finish is so poor, you can actually fit a Prius in the gap between the trunk lid and the fender.
Oh, that's priceless. I'm stealing that, thank you very much.
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That is so totally an exaggeration. No WAY can you fit a Prius. A Ducati, maybe.
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The *real* problem is that the frunk is too small to fit the Ducati.
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Wow, a car barely bumped a motorcycle at low speeds causing no damage. That never happens! Please, someone alert the world media!
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Someday I plan to buy a boat and haul it once a year for 1200 miles to Chesapeake bay from Tulsa OK. And if that trip can not be done in one tank of gas, that truck, that I have not bought yet, is totally worthless. So not only I won't buy it, nobody else will buy it either. So all electric cars are doomed to fail.
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I can't believe I forgot that one.
"Tesla won't be successful until their vehicles can haul a 20 ton boat over the Rockies during the winter on a single tank of gas on autopilot. I expect a vehicle to conform to my lifestyle, goddammit!"
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"Tesla won't be successful until their vehicles can haul a 20 ton boat over the Rockies during the winter on a single tank of gas on autopilot. I expect a vehicle to conform to my lifestyle, goddammit!"
ITYM:
"I expect a vehicle to conform ot the lifestyle I wish I had dammit!"
Now the bigger question is why some people do apparently fantasize about hauling very large things over steep terrain on a single tank of gas. I'd never have guessed it but honestly it does seem to be a thing.
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You ICE probably burns 10% more fuel after 160,000 miles and has probably lost power too.
Unless you completely rebuild the engine...
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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?)
I actually think you only hit half a hater point, the rest are new to me.
The one you got half-right is the recalls, which is related to the recent Tesla production issues, basically Tesla is still a new entrant to a very old industry. Re-inventing the car manufacturing process (as any new entrant must do) means you're going to make a bunch of screw ups along the way. Some will show up as production delays, others as recalls when the cars start breaking down in ways they don't expect.
But the real big "hater
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This is not correct.
1) The recall was on Model Ss. There are no production issues with the Model S.
2) The defect was in a Bosch part. Bosch supplies pretty much everyone, not just Tesla.
Re:Tesla is Done (Score:5, Interesting)
i did pick up that post was sarcastic. but still i feel like mentioning that my Tesla has worked just fine through two winters, including days well below freezing.
I also wanna mention just this spring, my family took the Tesla on a 550-mile road trip to Charleston, and it was a phenomenal trip. counter-intuitively, it was easier and more pleasant than it would have been in an ICE vehicle. Only had to stop every 4-5 hours or so, and since superchargers tend to be located in the parking lots of nice places to eat most of the time, it lined up perfectly with our meal schedules. the car was ready to go long before we were.
My wife thought we would have to take the minivan, because we don't pack light at all. But we were able to fit everything the four of us needed for a week in an unstocked beach house (including clothes / towels / food / toys / house supplies / beach chairs / pool noodles / etc) easily with plenty of room to spare. for a "sport sedan" the Model S has an unreal amount of cargo room.
also it's neat to drive 1200 miles on a vacation and spend $0.00 on fuel.
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Probably an artifact of the "full-size" hatchback design... The Model S has an unbelievable amount of cargo room for a "car".
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Only had to stop every 4-5 hours or so, and since superchargers tend to be located in the parking lots of nice places to eat most of the time, it lined up perfectly with our meal schedules.
Having a Tesla supercharger is likely to be a way to tell good restaurants from lesser competitors.
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"also it's neat to drive 1200 miles on a vacation and spend $0.00 on fuel." ...he/she said, having spent upwards of $75000 on a sedan to save what....$180 (assuming 20 mpg/$3 per gallon)
Look, you may love Teslas and it may work for your life-patterns, but let's not try to fool anyone that you're driving one to save money.
You could have purchased a BMW 6-series GT (assuming you want that 'level' of vehicle based on you having the $ to buy a Tesla in the first place) *retail* and saved about $4000 or about th
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Yeah, but I bet that if you drove the 6 series and the S back to back you'd choose the S. I have never driven either, but I'm about to sell my 3 series convertible because I prefer to drive my Leaf. And the Leaf is about the crappiest econobox EV you can get, with a battery tech which will probably see me losing 20% of my already paltry range in 5 years. And still, I enjoy driving the EV more.
If I can limp my other ICE along for a few more years, I hope to never have to buy another car with an ICE.
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No, normal people commute 500 miles with a fully loaded pickup truck every day... To a shack out in the hills where there is no electricity.
At least that's what at least one stereotypical hater usually comments on these threads :-)
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I know someone who salvages Teslas. If you want a salvaged one, I can point you in his direction. Then again, you refer to "salvage Teslas" despite saying that they don't exist, so I'm not sure how to interpret your post.
Temperature controlled (Score:5, Informative)
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There are 8 year old Nissan Leafs out there that suggest these numbers are looking quite reasonable. There were some early issues with the Leaf packs in certain climates that Nissan resolved, but beyond those they have proven to be remarkably reliable robust.
To this day Nissan has never sold a replacement battery pack (there is a part number and a price, about $4k). They removed the 80% charge long-life mode from newer models too, which is actually kinda annoying as it was more energy efficient too.
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$5,5k plus installation, according to this. [cleantechnica.com] For the 2011-2015 (84 mile) leafs.This more recent [electrek.co] article suggests $6,2k for the 24kWh, $7,6k for the 30kWh pack, and $7800 kWh for the 40kWh pack. Being made available in May. So I'm not sure where you're getting this "To this day Nissan has never sold a replacement battery pack" stuff.
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To date I don't think they have sold any replacement packs. They have done some under warranty but I don't know of any actual sales to someone who just wanted to replace their out-of-warranty one.
The new scheme is quite interesting. Maybe they have reached the point where they think there is demand, although you have to wonder if anyone will take them up... $6200 isn't much less than you can buy a good condition 24kWh Leaf for anyway.
Maybe if you could upgrade to the 30 or 40kWh pack or something it might b
Odd metric (Score:2)
How long did it take to get that many miles ? Not a really good metric. They need to quantify how long it took to get to that mileage, or how many recharge cycles that encompassed. If I drove 20k miles per year, or 40k miles per year, it makes a huge difference.
Survey? (Score:2)
Looks more like a web forum discussion. I have to admit, I was initially expecting another “internal”memo - Tesla’s PR wing has been working overtime to change the tone of the overall public discussion lately.
In any case, it’s not really news that the batteries of pretty much *all* EVs and Hybrids have lasted longer than was initially estimated, even before Tesla was a thing. So I’m not sure why this is particularly noteworthy. However it’s good news for Tesla owners, for
Gas Tank (Score:3)
And my Gas tank still has 100% capacity after 160,000 miles.
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analogy fail.
it's unlikely you are still getting the same MPG as when the car was new, at least not without rebuilding a number of major components. and if you are, you are an outlier.
Re:Gas Tank (Score:5, Funny)
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The garage was in the basement, I could smell gas, and was freaked out. Moved the car to drive way, worried sick, assumed the whole thing can explode any minute. The leak was very small but the underside was coated with gasoline. There was gasoline vapor under the car, there was this hot exhaust ... Shivers even now when I think about it.
Was exaggerating a little to say it lost 80% of the capacity. The leak was in the neck, near the gas filler cap.
Re: Gas Tank (Score:2)
But your engine and transmission are shite.
Percent Charging Power (Score:2)
Start making replacement batteries (Score:2)
IMNSHO, Tesla should start making after-market replacement batteries for the existing crop of hybrids, etc. Let's face it, most people aren't going to be trading "up" to a Tesla anytime soon. And while I understand their likely preference for a modularized battery, it seems like if they have better tech they could come up with something.
How about longevity? (Score:2)
I am impressed by the mileage numbers. But How can the Batteries and the rest of an Electric Vehicles' components be expected
to hold up over the long time?
I think it matters whether those 160,000 miles are due to frequent driving OR if those 160k miles are spread out over a long period of time.
Suppose I consider getting a model 3 versus and a recent Toyota gasoline model.
With an intention of keeping the car for at least 15 years. HOWEVER, In any case, I am concerned
about what the total and a
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You must really hate electric vehicle to be so negative. I think the fact that these batteries last 500,000 miles is pretty amazing. Usually lifetime warranties are not for batteries because no-one expects batteries to last a long time. Look at laptop batteries, they only used to last 2-3 years regardless of whether you even used the laptop.
"All this is saying is that a piece of technology didn't catastrophically fail." No, it's saying that the battery tech is very good and the batteries can be recharged a
Re:So Warranties and Guarantees dont describe qual (Score:5, Insightful)
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..
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They used to have an 80% charge option on older laptops, which was mysteriously removed from newer ones.
Fortunately there are still plenty of good laptops that don't have the battery glued in so you can replace it easily. Good ones don't need the battery to even be installed just to get maximum performance (like Macbooks do), so you can take it out and extend its life greatly by avoiding the heating/cooling cycles it experiences when installed but not used.
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18650 (18mm x 65mm) is a size. Implies nothing about the battery technology. Also Tesla is now using a 2170 (21mm x 70mm) cell which is not only 50% larger in volume/capacity, it can also deliver about 2x more instantaneous current due to the adjusted proportions.
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2170 (21mm x 70mm) Implies nothing about the instantaneous current as it also Implies nothing about the battery technology.
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"it can also deliver about 2x more instantaneous current due to the adjusted proportions."
Uh, no not really. It can deliver more current because of additional and thinner layers providing more surface area for electrons to travel across, plus a tweaked battery chemistry.
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Tesla does use 18650s (2170s in the Model 3) but their chemistry is "special"... not the same as laptop batteries.
Teslas do have a sophisticated battery monitoring system and a battery cooling/heating system to keep the batteries at a comfortable temperature. They don't overcharge the batteries and don't permit them to get run down too low. Charging at Superchargers is carefully controlled to keep the battery temperature and charge rate in the range that is healthy for the batteries.
This is much different t
Re:Tesla Batteries (Score:5, Informative)
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
Re: Tesla Batteries (Score:2)
If that's right, would they hold their overall charge capacity longer because people (I assume) keep them topped off and not routinely run them down to 0%?
You couldn't run them down to 0% if you wanted to; the software won't let you.
The exact percentages aren't publicised, but the onboard software likely only ever let's you charge up to maybe 85-90%, and discharge to 10-20%. If you actually could charge to 100% and discharge to 0% you would get a significant bump in range, but would also destroy the battery pack much faster.
I have an extended battery for my phone so I now do the same thing roughly; on a typical day I will limit the charge to 84% and dischar
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"A belt mounted phone clip can effectively double the lifespan of the battery."
This also makes for great birth control.
Re: Tesla Batteries (Score:2)
I don't think that's how you're supposed to use the clip ...
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Lithium batteries tend to lose capacity fastest when they're kept at full charge and high temperature.
If you manage temperature well and keep them between 20 and 80% charge, they'll last a long time.
I wouldn't be surprised if they over-provisioned the batteries to trade capacity for service length by not charging the cells as much as they could.
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It's a combination. Tesla locks off the top several percent (depends on the chemistry / pack, but say 5%) permanently, and the owner never sees it (the bottom is also locked off). Beyond this, however, owners generally only charge to 70-80% in their everyday life, because there's no need for more and it's good for longevity. You only charge up to "100%" (which is really ~95%) when you know you're going on a long trip the next day. Some people don't even do that. And almost nobody supercharges to 100%; i
Re: (Score:2)
Sounds like a pretty busy job, managing your charge level this way. Enthusiasts (the present customer base) may be into it. The general public won't be.
Re: (Score:2)
Yeah, they'd never have a slider on the charge settings screen where you can set the max charge level. Where they set it to 80% by default, and show that anything above is only for the roadtrip exception. Oh wait...
Re: (Score:2)
It should be possible to do analysis on changes that have occurred in cells over a short period of time and infer a future mode of failure. Don't ask me how specifically because I'm not a battery chemist.
Re:Survey? (Score:4, Insightful)
Hint: Tesla owners didn't collect this data for you. They collected it for themselves.
Re:Survey? (Score:5, Insightful)
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.
Re:Self selected survey, no reason to trust it (Score:4, Informative)
Tesla batteries have an eight year warranty. Tell us another one.
Re: Batteries will outlast the car (Score:2)
Most cars are junked because the engine and transmission wear out and need to be replaced or rebuilt. Teslas don't have either, just an electric motor with one moving part which should go for many more miles.