TonyWilliams
Well-known member
TimLee said:... Just like some of those early $10,000 plasma TVs had major deficiencies and experienced burn-in problems, we now know the 2011 / 2012 LEAF battery is first generation chemistry, 2013 is a bit better second generation chemistry, and 2014 (at least at some point in 2014 cycle) will be markedly improved much more heat tolerant chemistry.
We actually don't exactly know that the 2014 "Hot Battery" will in fact be "markedly improved". Yes, that's what they are saying today. But, the problem for me is that they have made a lot of statements in the past that didn't quite turn out to be accurate.
My point is that I'm confident that they ARE feverishly working on that better battery, however it sure took a lot of hammer hits to their respective heads to get the message that things wouldn't work out with the previous plan. The handwriting was on the wall for a LOOOOOoooooong time.
It was so painfully obvious that the gig was up last summer, that Mark Perry was telling folks that the battery would degrade quickly in heat when his boss was telling the press that it was all the "instruments" and the battery was fine.
So, I hope for the best. The Nissan LEAF is just too important to the EV movement to hope otherwise.
*******************************
2009 - Tesla CEO Elon Musk, well before LEAF was released for sale rips on Nissan's battery technology, and says it's "primitive" without a temperature management system.
January 25, 2010 Autoblog: "Is the Nissan LEAF Battery Pack under Engineered?".
From battery expert Charles Whalen:
"the LiMn2O4 chemistry, that both GM and Nissan are using in the Volt and Leaf, being the most heat sensitive and having the shortest life at higher ambients).... it is the combination of: a) the high ambients in hot climates like Phoenix and South Florida, b) the exponential nature of this Arrhenius function relating lithium battery life to temperature (where battery life roughly doubles for about every 25 degrees F reduction in temperature), and c) the high current cost of lithium batteries [$625/kWh for the Volt ($10,000/16kWh) and $750/kWh for the Leaf ($18,000/24kWh)], … that makes a liquid-cooled, water-chilled, active thermal management system economically advantageous and viable ***FOR AN EV THAT WILL SPEND ITS LIFE IN A HOT CLIMATE***."
A recent study by Pikes Research with U.S. Department of Energy data shows, lithium ion batteries (like those in the LEAF) exposed to hotter average temperatures lose their ability to store energy; the hotter the temperature the faster they lose their storing ability. So BEV owners in Phoenix will likely be looking to replace their batteries faster than owners living where the thermometer doesn’t often reach 110°F.
“Thermal management of lithium-ion battery systems is critical to the success of all-electric vehicles because extreme temperatures can affect performance, reliability, safety and durability,” says a Ford press release.
“Extreme temperatures impact a battery’s life and performance, making it crucial to have an effective cooling and heating system to regulate temperature for these demanding applications,” said Anand Sankaran, Ford executive technical leader, Energy Storage and HV Systems.
November 2011 - the first known Nissan LEAF had it's battery pack replaced.
April 2012 - another Phoenix area LEAF driver reported the same issues.
August 3, 2012 - Mark Perry, Director of Product Planning for Nissan North America. On August 3, 2012, he was reported to have said, "We've also been very transparent in making sure people know that battery capacity will degrade in very high heat – for instance, if the cars sit out in 110-degree heat for five hours a day."
September 4, 2012- Andy Palmer, executive vice president of Nissan also dismissed recent reports of battery problems in hot weather for the LEAF. A number of owners in America complained of reduced range during summer, but Palmer says the problem is a faulty battery level display.
"We don't have a battery problem," he says.