OrientExpress
Well-known member
That is an interesting argument Counselor. I'd be interested to see your case law basis.
Are you sure about that ?abasile said:That said, with four or five temperature bars, our LEAF's regen is now poor even at relatively low SOCs. On a long downgrade, the LEAF also tends to limit sustained regen. So even if I were to start the 4,900' descent with 15 kW of regen available on a good day, there'd be practically no regen available after maybe 2000' of elevation loss.
I know, it shouldn't be that way, as there ought to be plenty of room for a few kWh or so if the LEAF is charged to about 50%. (Remember that some of that potential energy is lost to friction, aero drag, and drivetrain losses.) But that's been my experience. At least it was my experience until last year when we got another EV which we use for all of our trips off the mountain, and I have no reason to believe the LEAF gets better with age!SageBrush said:Are you sure about that ?abasile said:That said, with four or five temperature bars, our LEAF's regen is now poor even at relatively low SOCs. On a long downgrade, the LEAF also tends to limit sustained regen. So even if I were to start the 4,900' descent with 15 kW of regen available on a good day, there'd be practically no regen available after maybe 2000' of elevation loss.
4900 feet is about 6 - 7 kWh of potential energy
Our MY2011 LEAF has lost three capacity bars and can charge at a rate of 25 kW up to about 70% SOC, yet the regen operates just as abasile describes. This evening I saw the regen put out about 10 kW when the car was traveling at about 40 MPH at the top of the mountain, but the power level dropped to about 5 kW after the car had sped up to 65 MPH. (On this mountain, about 20 kW is required to maintain a constant speed. Our 15.5-year-old Honda Civic Hybrid with its original battery (that has a BMS which has also been reprogrammed after a lawsuit) does a better job holding its speed on this mountain than the LEAF.SageBrush said:Interesting. That is unexpected.
What sustained charge rates during QC can the LEAF accept ?
No, the issues abasile describes are more significant when the battery is cold.SageBrush said:Is your traction battery actually hitting such high temperatures that it goes into a turtle-ish mode ?
Nah. They ALL work this way after the P3227 reprogramming. They are not likely to replace a battery that is working just like all other degraded batteries.SageBrush said:Nissan will probably try to tell you it is a matter of expected degradation, but they will be wrong.
Get your case documented before the 8/80 defect warranty lapses, and fight until you get the defect resolved.
No, I noticed this immediately after the P3227 update, my car was flashed in July '13. TomT and DaveinOlyWA also noticed, too. P3227 definitely reduced the amount of available regen.GerryAZ said:Those who claim the P3227 software update significantly reduced regeneration probably did not have enough degradation to notice the reduced regeneration as the weather cooled in the fall of 2012.
GerryAZ said:The original 2011 and 2012 batteries from Japan have higher internal resistance after some degradation than the 2015 lizard batteries. The internal resistance also increases as battery temperature decreases. I saw the regeneration drop significantly on my 2011 as the ambient temperatures cooled off in the fall of 2012 (long before the P3227 software update was issued) when it had 10 capacity bars. I saw no change to regeneation when the P3227 software update was performed as part of the testing after the car was down to 8 capacity bars in the summer of 2013. Regeneration was restored when the battery was replaced in October of 2013, but available regeneration was already dropping by the time the car met its demise in January 2015. Those who claim the P3227 software update significantly reduced regeneration probably did not have enough degradation to notice the reduced regeneration as the weather cooled in the fall of 2012. The software update on most cars was done during the spring and summer of 2013. The loss of regeneration was heavily discussed on the forum during fall and winter of 2013 after cars in mild climates had enough battery deterioration to make it noticeable.
In contrast, my 2015 has significant regeneration available within a mile or two after leaving the house with a full charge (even with over 50,000 miles on the original battery).
drees said:No, I noticed this immediately after the P3227 update, my car was flashed in July '13. TomT and DaveinOlyWA also noticed, too. P3227 definitely reduced the amount of available regen.GerryAZ said:Those who claim the P3227 software update significantly reduced regeneration probably did not have enough degradation to notice the reduced regeneration as the weather cooled in the fall of 2012.
DaveinOlyWA said:I have to side with the masses here. I think you have a very valid claim and not so much on Poor programing causing lack of regen, excessive degradation, etc.
Simply a car designed with insufficient braking power. You should not have to stop several times going down the mountain. I used to live in Riverside, so have a pretty good idea of your location and have been up and down that mountain many times and yeah, its hell on brakes for sure but its not that bad.
You have a serious performance issue that borders on a major safety violation.
drees said:I don't notice much of a difference in the internal resistance of my replacement pack and my original pack when new. LeafDD reports 75-85 mOhm depending on pack temperature. I recall only slightly higher values by the time I had LeafDD on my original pack.
The '13+ LEAFs just seem to have much more aggressive regenerative braking profiles than the '11-13, especially after the P3227 update.
I'm sure that the pack's internal resistance sets a ceiling on available regen or QC. The problem is that this ceiling seems to then be subject to other non-sensical factors like vehicle speed and amount of recent regen. I think that Nissan has intentionally crippled the regen performance.GerryAZ said:My experience is that the lizard battery in the 2015 has much lower internal resistance so the LBC (lithium battery controller) can allow much higher regeneration rates (or quick charge rates) without reaching maximum cell voltage.
Has anyone found a way to hack the LEAF and install an earlier firmware version? This is probably not a good idea for anyone desiring to file a claim with Nissan or reach a settlement. Otherwise, if we end up having to keep the original battery (and I'm almost certainly not paying $5K for a new, puny 24 kWh battery in a car that's barely worth $5K), then I'd love to try un-doing P3227 if it's feasible without spending tons of hours.DaveinOlyWA said:Not sure about that either. without checking, it seems like neither my 2013 or 2016 had as much as my "unaltered" 2011 did.
Okay, it's true that practically every used car has at least some value, even if it's just for the scrap metal. However, unless it's been in a wreck, a six or seven year old vehicle should still have plenty of functional value. Our 2011 LEAF still has functional value to us, but it is severely compromised relative to what I'd consider pretty reasonable expectations. I'm only mentioning the low resale value in making the point that I cannot justify spending $5k out of my own pocket on a replacement "24 kWh" battery.DaveinOlyWA said:well thinking of your EV as throwaway is on you. It has value to someone but not to you. Now evaluating low resale as throwaway is a good argument but the reality is low resale applies to everything that is 7 years old.
When we purchased the LEAF in April 2011, Nissan did warn us in writing that the battery might lose plus or minus 20% of its capacity in five years. Given our cool microclimate and the benefits of cool temperatures for battery longevity, I was expecting that we'd be on the low end of this, and we instead exceeded 20% loss. (Our LEAF is still on the low end of capacity loss relative to other cars in California, of course.)DaveinOlyWA said:But your elevation challenges makes it a safety hazard imm. Range is not good but a lot of people less on a regular basis.
With an especially cold battery and/or high state of charge, any BEV will have limits on regenerative braking. This is characteristic of the technology, at least as it exists today for all known BEVs, and should not itself be considered a "defect". Just as ICE cars have their particular quirks and limitations, this is a BEV-specific behavior pattern that drivers need to be prepared for.Reddy said:Abasile: I'm willing to join you on this topic. Even though I live on the flats, my original 2011 battery has nearly zero regen when cold (it's just starting for this winter, essentially anything under 50 F) unless I'm driving less than 35 mph and have less than 50% SOC. Range is not a problem since my commute is 8 mi RT and our community is pretty small. However, the lack of regen (especially for the unobservant masses) make it difficult to gauge stopping distances without using the friction brakes. My hypermileing skills are suffering greatly. :x
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