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Nissan Leaf Owners Hope For The Best, Fear The Worst

Enviado: 26 ago 2012, 19:38
por ruimegas
Nissan Leaf Owners Hope For The Best, Fear The Worst

[IMG]http://www.hybridcars.com/files/Drozd%2 ... 20side.jpg[/IMG]

"Be it a tempest in a teapot as Nissan has loosely suggested, or further damage to the EV movement brewing, eyes are on the maker of the all-electric Leaf following its analysis of customer cars suffering premature battery failure.

A few weeks ago – Nissan will not divulge exactly when – the company borrowed and tested seven of the worst Leafs out of dozens believed to be experiencing substantial range loss.

The common denominator for the alleged battery degradation for these Arizona Leafs has been ambient heat, as is true also of cars reported in Texas and California thus far.

The brewing discontent among early adopters in the MyNissanLeaf.com forum is being monitored by Nissan – as noted by tracking of Tennessee and Japanese IP addresses – and the company in July issued an open letter saying it had only just been made aware of problems, valued its customers and would follow through.

Meanwhile the forum members are sifting the tealeaves for portents for how Nissan will respond, how they will in turn respond, and some note with dismay the Leafmaker’s actual lack of an attitude perceived as sufficiently forthcoming.

According to one of a few wiki pages compiled by intrepid and tech-savvy early adopters, 33 Leafs currently have one bar loss out of 12 total bars on their digital battery gauges. An additional 19 cars currently have two bars missing – putting them deep into the zone where Nissan said would not happen for many years, and five cars have reported three bars lost.

The Leaf service manual says the first capacity bar loss represents a 15-percent loss, while each subsequent bar stands for a 6.25-percent additional loss.

There is evidence to suggest further that once these allegedly heat-degraded batteries begin to fade, they go down hill rather fast.

When we last looked at these issues late in July, we were following the case of Nathan Drozd in Texas who describes he and his wife as quintessential early adapters. Drozd’s Leaf lost its first battery capacity bar on the car’s one-year anniversary, and grimly said if he fits the trend, he expected to lose his second bar by August.

Sad to say, Drozd was right on the money.

“Just wanted to let you know, I lost my second bar today,” said Drozd via e-mail last week. “It was 23,652 miles on the odometer (3,446 from 1st bar to second bar loss). Time was almost exactly two months from the first bar (14 months total from ownership), it will be two months tomorrow.”

Nissan has said it should take five years or longer for a battery to be degraded to 80-percent charge-holding capacity, and being a technical endpoint for its specified service life – while the degraded battery could keep going as-is – it could also be said to be due for replacement. If Drozd’s battery gauge in his 14-month-old Leaf is accurate, it is telling him he is at 78.75 percent.

[IMG]http://www.hybridcars.com/files/100percentSOC.jpg[/IMG]
With the battery 100-percent charged, this is what Drozd sees on his battery meter.

Among the possibilities being explored is that the on-board battery meter could be inaccurate, along with other potential software issues, but a number of engineers and technically knowledgeable folks besides have been monitoring their state of charge independently with their own CAN Bus-connected meters.

As for Drozd, he has simply noted significantly less traveling range compared to when his car was newer which roughly corresponds to what his battery gauge says.

What’s more troubling are anecdotal reports that upon bench testing some of the worst customer cars' batteries, Nissan suggested they were in better shape than their owners believed they knew to be the case.

This trend was also alleged first at the dealer level, where missing bars have been portrayed as “normal.”

But Nissan has also already replaced at least one Leaf battery in the Phoenix area. That was reportedly in November 2011, and another was replaced in April 2012. Since then – and to keep mixing metaphors – the overheated Leaf battery problems have snowballed ever since.

So where are things now?

Officially Nissan’s jury is still out. We contacted the company and spokesperson Katherine Zachary said today she could share very little, although she did say a total of seven cars were tested.

The MyNissanLeaf forum members – sifting the tealeaves – have heard from at least six owners who had their cars thoroughly tested, and rumor had it this could be as many as 11 Leafs tested. Today Nissan specified the count, but that’s all it has to say.

“We are studying the results of the seven cars tested and will let you know when we have something to share,” Zachary said.

Another aspect of this mystery already known is Nissan covered itself when it launched the car by not offering a battery warranty that would address issues like those now being experienced. The Chevy Volt battery is by contrast warranted, as is the similar battery in a Nissan alliance partner Renault Fluence Z.E..

It’s been observed the Volt’s battery affects emissions controls, as a degraded battery would make the engine run more often, but a Leaf with a degraded battery still emits nothing. Beyond this, Nissan has taken the warranty posture it has, which contrasts to General Motors which already suffered through the EV1 debacle, and in any case has learned some public relations lessons.

The Volt’s battery – as is true for Tesla’s – is furthermore more thoroughly engineered with a liquid cooling/heating thermal management system.

In February this year, Nissan said in an article touting its EV prowess that a liquid heating/cooling thermal management system was not necessary for U.S. climates.

In 2010 Wired ran a report suggesting the battery was under-engineered, and that was turned into an Autoblog post which has since proven potentially prophetic.

As patience is now being urged by Leaf owners, comments on the owners’ forum run the gamut, and all options are being explored.

One occupational hazard Nissan essentially took in creating an advanced battery electric vehicle is it attracted some forward-thinking people as its first customers. Many of these folks tend to be well educated, informed, proactive, assertive, and they are watching Nissan for potential improprieties, some of which have already been noted."

[IMG]http://www.hybridcars.com/files/Leaf_ch ... tny_ad.jpg[/IMG]
Leaf owners have also reported being solicited by attorneys, and here's a partial screen shot from a Web page for one firm fishing for business.

Em: http://www.hybridcars.com/news/nissan-l ... 50263.html

Re: Nissan Leaf Owners Hope For The Best, Fear The Worst

Enviado: 26 ago 2012, 23:47
por RJSC
Será por isto que a Renault desistiu de usar as baterias da Nissan no ZOE e Twizy e passou para as LG? :roll:

Isto assim está muito mau!
O mjr disse que a garantia da bateria cobre não a capacidade, mas apenas potência.
Assim pode ter-se uma bateria com 20 km de autonomia que ainda entregue os 80 kW ao motor e a Nissan não trocar porque o carro ainda tem aceleração, apesar de ter uma autonomia miserável.
Pode ser que os Americanos tenham mais sorte, já que a garantia deles não é igual: têm 8 anos em vez de 5 e às tantas a deles até pode cobrir perda de capacidade.

Se isto começar a acontecer em Portugal estão tramados pois enquanto o carro responder com 80 kW ao acelerador mesmo que seja apenas por 1 km, a Nissan está a cumprir com o que está escrito na garantia e não troca a bateria.

Re: Nissan Leaf Owners Hope For The Best, Fear The Worst

Enviado: 27 ago 2012, 01:01
por Malm
No caso do I-MiEV, na garantia da bateria (5 anos), penso que se referem a perdas acima do normal na capacidade. Resta saber o que é que eles consideram perdas acima do normal resultantes de uso normal. E perdas, no meu carro, com 28.000 km e 17 meses de uso, pelas distâncias que continuo a percorrer, não me parece que sejam mais de 10%. Pelas minhas contas, falíveis porque são baseadas essencialmente na minha experiência de condução, as perdas devem rondar os 5%. Não tenho conhecimento de casos de perdas semelhantes ao que se passou com esses Leaf em I-MiEV e seus clones.

Re: Nissan Leaf Owners Hope For The Best, Fear The Worst

Enviado: 27 ago 2012, 14:53
por mjr
Se houver iMiEVs no deserto (o Arizona fica num deserto) devem ser muito poucos.

A garantia do Leaf só cobre a potência, seja em que parte do mundo for.

A resistência interna de uma bateria segue a capacidade restante, pelo que uma bateria com 50% da capacidade terá o dobro da resistência interna original e por isso só poderá entregar metade da potencia máxima original. No Leaf a potencia disponivel da bateria é muito superior aos 80kW do motor. Pelas minhas contas o Leaf deve começar a limitar a potencia quando a capacidade restante da bateria estiver entre os 30-50%

Re: Nissan Leaf Owners Hope For The Best, Fear The Worst

Enviado: 24 out 2015, 11:02
por Filipe

Re: Nissan Leaf Owners Hope For The Best, Fear The Worst

Enviado: 24 out 2015, 13:47
por Fil
RJSC Escreveu:Será por isto que a Renault desistiu de usar as baterias da Nissan no ZOE e Twizy e passou para as LG? :roll:

Isto assim está muito mau!
O mjr disse que a garantia da bateria cobre não a capacidade, mas apenas potência.
Assim pode ter-se uma bateria com 20 km de autonomia que ainda entregue os 80 kW ao motor e a Nissan não trocar porque o carro ainda tem aceleração, apesar de ter uma autonomia miserável.
Pode ser que os Americanos tenham mais sorte, já que a garantia deles não é igual: têm 8 anos em vez de 5 e às tantas a deles até pode cobrir perda de capacidade.

Se isto começar a acontecer em Portugal estão tramados pois enquanto o carro responder com 80 kW ao acelerador mesmo que seja apenas por 1 km, a Nissan está a cumprir com o que está escrito na garantia e não troca a bateria.
Trocou a do Paulo Guerreiro, será que foi por ai? Não me parece. Pelo menos não o vi queixar-se de falta de potência, mas sim de falta de barras (autonomia).