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Re:How automakers can drive electrified vehicle sales and pr... by jjawssd on Thursday February 02, 2017 @08:00PM (#13556701)
Lithium ion battery capacity decays with each charge down to 50% after 500 cycles
Re:How automakers can drive electrified vehicle sales and pr... by Reason077 on Thursday February 02, 2017 @08:39PM (#13556907)
capacity decays with each charge down to 50% after 500 cycles

Not true with modern EV batteries. Tesla's packs typically show less than 8% degradation after 100,000 miles, which would be approximately 500 cycles.

https://electrek.co/2016/06/06/tesla-model-s-battery-pack-da...

Re:How automakers can drive electrified vehicle sales and pr... by applecore on Thursday February 02, 2017 @09:44PM (#13557225)
Tesla batteries only show very little degradation because their capacity is limited by software[1]. You can "increase" your battery capacity by ordering a $9,000 software update.

[1]: https://electrek.co/2016/07/26/tesla-upgrade-software-limite...

Re:How automakers can drive electrified vehicle sales and pr... by will_hughes on Thursday February 02, 2017 @10:13PM (#13557354)
>You can "increase" your battery capacity by ordering a $9,000 software update.

Thats only for certain specific model and delivery time combinations.

i.e just before they introduced the 90kWh option in production, some 85kWh cars were shipping with the 90kWh pack.

If you ordered a particular pack before the next step size started shipping, then that's all you got.

>Tesla batteries only show very little degradation because their capacity is limited by software

Not true. It's mostly to do with active management of the battery, and keeping it within the optimal conditions for much of it's life. These are things your phone and laptop can't (or rather: don't) do.

Everyone tends to plug in their laptop/phone and charge to 100%, then leave it there for long periods of time. Plus, laptops and phones tend to get very hot, and there's no active cooling of the battery.

This combination of conditions tends to reduce the life of batteries significantly.

Re:How automakers can drive electrified vehicle sales and pr... by ksrm on Friday February 03, 2017 @03:35PM (#13563069)
>Everyone tends to plug in their laptop/phone and charge to 100%, then leave it there for long periods of time.

Why is this a problem for Lithium batteries?

Re:How automakers can drive electrified vehicle sales and pr... by will_hughes on Friday February 03, 2017 @07:29PM (#13564685)
Leaving lithium batteries at their extremes of charge state reduces their lifetime.

Tesla recommends that their customers to charge to only about 80% for normal daily driving, and that if they need the full 100% range that they should start driving very soon after it reaches 100% charge. They also recommend not leaving it at empty for very long too as empty cells are more likely to drop below their minimum voltage, and die.

Re:How automakers can drive electrified vehicle sales and pr... by maxsilver on Thursday February 02, 2017 @09:20PM (#13557092)
I own an electric car (with a lithium ion battery) and commute daily with it.

It's now four years old, has driven over 45,000 miles (well over 500 cycles) and the total degradation is less than 10%.

Re:How automakers can drive electrified vehicle sales and pr... by Flemlord on Friday February 03, 2017 @12:00AM (#13557803)
Me too. Just traded in a 4yr old Model S with 52k miles and saw <10% degradation. Fully charged, it was 210 miles new, and about 192 after 4 years.
Re:How automakers can drive electrified vehicle sales and pr... by mikeash on Thursday February 02, 2017 @08:19PM (#13556817)
That depends greatly on the specific battery chemistry, the temperatures the battery is exposed to, the charge levels, the charge rates, etc. You can't just make a blanket statement like that.
Re:How automakers can drive electrified vehicle sales and pr... by ebbv on Thursday February 02, 2017 @09:02PM (#13557009)
This is a bullshit statistic that has somehow become a meme on the internet. It just flat out isn't true. There's EVs with over a hundred thousand miles on the original pack still doing great. Please stop repeating nonsense as if it is a fact.
Re:How automakers can drive electrified vehicle sales and pr... by grzm on Thursday February 02, 2017 @09:18PM (#13557086)
I understand how frustrating that can be. Do you have a reference at hand that busts this myth?
Re:How automakers can drive electrified vehicle sales and pr... by jccooper on Friday February 03, 2017 @12:16AM (#13557859)
Well, here's some data from a decent number of Tesla Model S in the wild:

https://survey.pluginamerica.org/model-s/charts.php

I'd say it looks like they behave rather well in general.

Re:How automakers can drive electrified vehicle sales and pr... by grzm on Friday February 03, 2017 @01:33AM (#13558183)
Thanks! That is pretty impressive.
Re:How automakers can drive electrified vehicle sales and pr... by ebbv on Thursday February 02, 2017 @10:30PM (#13557442)
Guy #1: Shaking pinecones will scare snakes away.

Guy #2: No it won't.

Guy #3: Do you have any sources that disprove that claim?

The onus is on the person making the ridiculous claim.

I can tell you from personal experience I have had a Nissan LEAF for about 2.5 years and ~24k miles, driven daily and it has lost no range whatsoever. But if you want a study or something, you're gonna have to Google for yourself man.

Re:How automakers can drive electrified vehicle sales and pr... by grzm on Thursday February 02, 2017 @10:38PM (#13557467)
Hey, your anecdotal experience is better than nothing. I'm reading this thread as an interested observer.

Both you and 'jjawssd are making claims, and you're very confident that 'jjawssd is wrong.

This is a bullshit statistic that has somehow become a meme on the internet. It just flat out isn't true.

I don't think it's unreasonable to expect someone who expresses that level of confidence to have something to back it up. And if the false claim is so widespread, I'd also expect someone to have busted it and publicized it. From my outside, ignorant point of view, both sides are unproven, with an edge to you because of your own experience.

Re:How automakers can drive electrified vehicle sales and pr... by ebbv on Thursday February 02, 2017 @11:16PM (#13557632)
We aren't both making claims. He's making a claim and I'm saying it's an unsubstantiated internet meme. My little joke example was meant to illustrate that.

I'm sure you have devices in your own life that disprove his claim. Look at your phone. Does it really go to 50% capacity after 500 days? None of mine have. Sure batteries degrade over time and you'll experience better performance one day or worse another, but he's claiming after 500 days of using your phone you should be at 50% capacity. That's obviously baloney.

Re:How automakers can drive electrified vehicle sales and pr... by grzm on Thursday February 02, 2017 @11:35PM (#13557716)
You are both making claims, the positive and negative of a particular characteristic of batteries.

When I first read your comment, I thought you were a little over the top, but it sounded like you likely had something solid to back it up, so I was interested in learning something new. Personally, I don't make strong statements like that unless I can pretty quickly defend them. I honestly wasn't trying to catch you out. And seeing a myth busted is generally a good time!

As for phone batteries, I just had to replace mine, so that's not a particularly useful example. As I understand it, there's a lot of circuitry in phone batteries these days anyway, so I'm not sure what failed. I'm not going to use my anecdotal evidence for or against your case, for what it's worth.

Be well!

Re:How automakers can drive electrified vehicle sales and pr... by ebbv on Thursday February 02, 2017 @11:40PM (#13557745)
If I had said "No they maintain 100% at 500 cycles." Then I would also be making a claim. I made no claim, I just said his claim is an internet meme that is bullshit. There's a big difference. I'm not sure why this is so hard for you to understand.

I don't save a folder full of links to answer skeptical people on the internet and I'm not going to Google for you. If you're interested in reading articles, go look for yourself.

Anyway whatever. This has been a colossal waste of time.

Re:How automakers can drive electrified vehicle sales and pr... by Erem on Friday February 03, 2017 @04:28AM (#13558748)
What an unreasonably combative response.

Next time just say "sorry I don't have hard evidence for this opinion on hand". Nobody expects you to know everything but they do expect you to treat people decently.

Re:How automakers can drive electrified vehicle sales and pr... by sokoloff on Friday February 03, 2017 @05:13AM (#13558872)
My 2.25 year old LEAF with ~9000 miles on it has lost about 5% capacity. I'd be very surprised to learn yours has not lost any capacity.

Are you relying only on the 12 bar indicator or on the more detailed data download from the car's telemetry? My car still shows 12 bars, but has obviously lost some capacity (max range at 100% charge is down to about 95 from 102/103), just like my phone that still charges to "100%" but obviously has way less capacity after 3 years.

From my perspective, losing "no range whatsoever" after 2.5 years is the extraordinary claim.

Re:How automakers can drive electrified vehicle sales and pr... by ebbv on Friday February 03, 2017 @07:21AM (#13559282)
I haven't downloaded the telemetry but we drive it every day and the range we get is extremely consistent. I'm sure there must be some degredation but my point is we haven't really lost any range. The weather and our driving behavior is the main cause of range variation.

If his claims about losing 50% capacity after 500 cycles were remotely true that would be the main cause of lost range ina 2.5 year old LEAF.

Re:How automakers can drive electrified vehicle sales and pr... by thephilsproject on Friday February 03, 2017 @05:40AM (#13558945)
From my understanding, the LEAF has a primitive battery management system compared to other EVs, including passive air cooling of the battery. Lithium batteries are fussy about temperature (they have similar temperature preferences to humans) and outside of this the degradation can be faster. Other EVs have liquid heating and active cooling of the battery.
Re:How automakers can drive electrified vehicle sales and pr... by sokoloff on Friday February 03, 2017 @06:26PM (#13564275)
The LEAF does have a battery heater I'm pretty sure.