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Post by jake on May 9, 2016 11:14:10 GMT 11
I always thought part of it was temperature dependent. I found mine decreases over summer and creeps back up a bit in the cooler months. A few days in the sun would bring down the SOH and a weekend in the underground garage would bring it back up, etc. Your graph seems to suggest that too. Yep, the cooler you keep your car, the longer the battery will last.
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Post by Phoebe on Jun 8, 2016 15:18:12 GMT 11
I have just lost my first bar, 3 years and 7 months after I got my LEAF with the speedo now at 7378kms. Always keep it cool so I reckon time is a bigger factor than distance travelled, at least for me.
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Post by hieronymous on Jun 8, 2016 16:58:55 GMT 11
I have just lost my first bar, 3 years and 7 months after I got my LEAF with the speedo now at 7378kms. Always keep it cool so I reckon time is a bigger factor than distance travelled, at least for me. Commiserations, Phoebe, you have been ever hopeful of holding off the evil day Given your infrequent use, I suggest you try what I do, and limit your charge level to 2 bars at all times except when you have a longer distance in mind. With that much charge I can easily get 20+ km above LBW, and comfortably get another 15km below that without worrying about running out - it might work for you locally.
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Post by Phoebe on Jun 8, 2016 17:19:17 GMT 11
That would mean charging a lot more often. I only charge once every 2 or 3 weeks so I think I'll stick with what I am doing, because my current routine works for me as I always pick a sunny day so that what I get from the sun, topped up with my battery storage, more or less does the job, even at this time of the year.
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Post by jeffthewalker on Jun 8, 2016 18:05:41 GMT 11
I have just lost my first bar, 3 years and 7 months after I got my LEAF with the speedo now at 7378kms. Always keep it cool so I reckon time is a bigger factor than distance travelled, at least for me. I should consider myself lucky. I have now done 18,000km and still to lose a bar. My only concern is that I register 56Ah (when full) in LEAF Spy and have never seen over 60Ah like some others have.
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Post by hieronymous on Jun 8, 2016 18:54:16 GMT 11
Of course, I was forgetting your PV panels & battery. Your "Big Picture view" is completely different to mine! My costs are constant, so I charge every couple of days, overnight.
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Post by EVangelist on Jun 9, 2016 0:11:03 GMT 11
I have just lost my first bar, 3 years and 7 months after I got my LEAF with the speedo now at 7378kms. Always keep it cool so I reckon time is a bigger factor than distance travelled, at least for me. At that rate, your Leaf should last about 40 years
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Post by jacky on Jun 9, 2016 13:50:54 GMT 11
I have just lost my first bar, 3 years and 7 months after I got my LEAF with the speedo now at 7378kms. Always keep it cool so I reckon time is a bigger factor than distance travelled, at least for me. Do you know when your LEAF was built? Mine was November, 2012 and still have 12 bars. If time is a big factor, it should loss a bar in the next 1-3 months.
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Post by Phoebe on Jun 9, 2016 16:23:24 GMT 11
I have just lost my first bar, 3 years and 7 months after I got my LEAF with the speedo now at 7378kms. Always keep it cool so I reckon time is a bigger factor than distance travelled, at least for me. Do you know when your LEAF was built? Mine was November, 2012 and still have 12 bars. If time is a big factor, it should loss a bar in the next 1-3 months. April 2012
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Post by jeffjl on Jun 10, 2016 15:43:25 GMT 11
Do you know when your LEAF was built? Mine was November, 2012 and still have 12 bars. If time is a big factor, it should loss a bar in the next 1-3 months. April 2012 POW! Way to go Phoebe. Make the rest of us feel jealous.:-)
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Post by jacky on Jun 13, 2016 15:12:12 GMT 11
Just lost the first bar this morning at 34,400 km.
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Post by jake on Jun 15, 2016 0:57:00 GMT 11
I have just lost my first bar, 3 years and 7 months after I got my LEAF with the speedo now at 7378kms. Always keep it cool so I reckon time is a bigger factor than distance travelled, at least for me. Your car was always going to be the deciding factor for me. So it seems the age of the battery is a bigger factor than I thought.
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ant
EV Enthusiast
2012 Leaf, EV enthusiast, AEVA WA Secretary
Posts: 43
LEAF OWNER?: Yes
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Post by ant on Jun 20, 2016 17:03:45 GMT 11
Bought my 2012 ( of course this info is redundant in Aus.. ) Leaf ( with 15 000km on the clock four months ago, had one bar already gone. By the time I managed to plug in and use Leaf Spy Pro, it was at 79% SOH. Not long after that it was at 78%. I think if I had known that the battery was so low I doubt I would have bought it. Fully expect to see the second bar go any time now, having now done an additional 2 500km. I suspect that , being a demo, the car was left at full charge outside the dealership in the full sun and that in Western Australia means HOT! and that this was the major factor in the battery degradation. In a way, I hope the battery now degrades below 9 bars by 2017 as I would then be able to call in the warranty - but worst case scenario is that it degrades to 9 bars by the time the warranty expires... Not happy Nissan..
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ant
EV Enthusiast
2012 Leaf, EV enthusiast, AEVA WA Secretary
Posts: 43
LEAF OWNER?: Yes
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Post by ant on Jun 20, 2016 17:05:13 GMT 11
Just lost the first bar this morning at 34,400 km. What does Leaf Spy Pro say?
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Post by jacky on Jun 20, 2016 18:35:18 GMT 11
Just lost the first bar this morning at 34,400 km. What does Leaf Spy Pro say? I don't have the dongle.
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Post by rusdy on Jun 20, 2016 19:42:30 GMT 11
Bought my 2012 ( of course this info is redundant in Aus.. ) Leaf ( with 15 000km on the clock four months ago, had one bar already gone. By the time I managed to plug in and use Leaf Spy Pro, it was at 79% SOH. Not long after that it was at 78%. I think if I had known that the battery was so low I doubt I would have bought it. Fully expect to see the second bar go any time now, having now done an additional 2 500km. I suspect that , being a demo, the car was left at full charge outside the dealership in the full sun and that in Western Australia means HOT! and that this was the major factor in the battery degradation. In a way, I hope the battery now degrades below 9 bars by 2017 as I would then be able to call in the warranty - but worst case scenario is that it degrades to 9 bars by the time the warranty expires... Not happy Nissan.. Don't lose hope yet. You'll probably find your SOH increase over time as I did (mine increased by 3% to date). My guess, the SOH prediction is not that great (I can't blame them, SOH accurate measurement is a rocket surgery / brain science in itself). My finding here.
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Post by 4wardthinking on Aug 12, 2016 11:33:28 GMT 11
Well, having mastered the Prius module adverse propaganda, I feel I should now have a go at dispelling the mist surrounding the Lithium power pack used in the LEAF. Firstly, I carried out an experiment on LiOn 18650's I have an abundance of. I have them sat charged to 95%, which is slightly higher than achievable on a Leaf pack due to its self protection algorithms incorporated in the vehicle. I sat down for weeks testing, charging and loading them. Eventually I weeded out the weak & no-go ones. I placed the 0.4v items in a poly box some 18 months ago, and almost left them until recently, I had occasion to 're-discover' them as I was looking for a few to replace sad ones in an appliance we have. The up-shot is I decided to experiment with three in particular. These over heated, and generally failed all use ability openings in the past. So, I prodded and poked them, and with very little a do, now had them holding charge. I then set out with an intelli charger to push them to a point where they would absorb no more power past the heat producing curve exhibited by them under complete absorption. I then set out to load them to test their output measured carefully. Result was first pass gave 2500mAh. Not bad for a rated cell of 2600mAh. These are a reputable cell manufacturers item, so I have little doubt on their official rating, although I accept that no two cells are identical. I recreated the same conditions, applied the same methodology, and came up with the same results. Off I did the same procedure once more, and a similar result was noted. Odd!, possibly, but consider many reasons why I had been inundated with statements and forecasts in the past years, but I, as per usual, set out to test the claims. I have them sat right beside me now, laid idle for 4 weeks. They have not exploded, bulged, gassed, generated any kind of heat. I monitor them with an IR thermometer twice daily. So, there's an interesting result to say the least. Now I don't have to buy more.....
To follow. A documented test of the Leaf power pack. Bought with 74% SOH showing on LeafSpy. Things are changing in this already in my first pass of evaluation. I am not!. For the Nissan Warranty Spies!!, doing anything un-toward to the pack. I note the system attains its SOH based upon "useable" absorption and capacity, which is now in my mind directly related to the "Gid". I am close to establishing its real annotation, and what it is indicating. I will continue in another thread when I have tested the theory. I also am forming a way to increase the "aging" packs potential. Interesting times ahead. When I have proof, I will do a write-up for all to consider.
Keep waving at the fossil Servo's guys!.
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ant
EV Enthusiast
2012 Leaf, EV enthusiast, AEVA WA Secretary
Posts: 43
LEAF OWNER?: Yes
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Post by ant on Aug 25, 2016 15:48:59 GMT 11
Well, having mastered the Prius module adverse propaganda, I feel I should now have a go at dispelling the mist surrounding the Lithium power pack used in the LEAF. Firstly, I carried out an experiment on LiOn 18650's I have an abundance of. I have them sat charged to 95%, which is slightly higher than achievable on a Leaf pack due to its self protection algorithms incorporated in the vehicle. I sat down for weeks testing, charging and loading them. Eventually I weeded out the weak & no-go ones. I placed the 0.4v items in a poly box some 18 months ago, and almost left them until recently, I had occasion to 're-discover' them as I was looking for a few to replace sad ones in an appliance we have. The up-shot is I decided to experiment with three in particular. These over heated, and generally failed all use ability openings in the past. So, I prodded and poked them, and with very little a do, now had them holding charge. I then set out with an intelli charger to push them to a point where they would absorb no more power past the heat producing curve exhibited by them under complete absorption. I then set out to load them to test their output measured carefully. Result was first pass gave 2500mAh. Not bad for a rated cell of 2600mAh. These are a reputable cell manufacturers item, so I have little doubt on their official rating, although I accept that no two cells are identical. I recreated the same conditions, applied the same methodology, and came up with the same results. Off I did the same procedure once more, and a similar result was noted. Odd!, possibly, but consider many reasons why I had been inundated with statements and forecasts in the past years, but I, as per usual, set out to test the claims. I have them sat right beside me now, laid idle for 4 weeks. They have not exploded, bulged, gassed, generated any kind of heat. I monitor them with an IR thermometer twice daily. So, there's an interesting result to say the least. Now I don't have to buy more..... To follow. A documented test of the Leaf power pack. Bought with 74% SOH showing on LeafSpy. Things are changing in this already in my first pass of evaluation. I am not!. For the Nissan Warranty Spies!!, doing anything un-toward to the pack. I note the system attains its SOH based upon "useable" absorption and capacity, which is now in my mind directly related to the "Gid". I am close to establishing its real annotation, and what it is indicating. I will continue in another thread when I have tested the theory. I also am forming a way to increase the "aging" packs potential. Interesting times ahead. When I have proof, I will do a write-up for all to consider. Keep waving at the fossil Servo's guys!. I will be awaiting your results with a keen interest - I did notice that when I had my iMiEV the battery revived ( counter intuitively ) and range increased about 10% after a few DC fast charges from flat to full in a row, not sure whether that was conincidence ( start of summer ) or not. But the leaf is degrading ( lost second bar recently ) and if there is a way to kick an extra few % out of it, I would be a much happier
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Post by 4wardthinking on Aug 25, 2016 17:04:41 GMT 11
My first and on-going logic is to allow the pack to determine its parameters, akin to the "great cell memory" propaganda mischievously banded about. There is no such thing. The logic of mine follows the idea of draining the pack as far as it would go a number of times, and only charging back to 15%. Eventually the balancing circuitry is constantly pushing power from one cell to the next, as seen on leaf spy as it happens. The visual is probably not as physical connections remember. I have spent four days doing this to my pack of ten bars. The pack has to have the lowest point defined electrically. Imagine losing top 5%, and bottom 5%, that would rapidly give you 90% capacity. The most power a pack is capable of is between the weakest and strongest cells. You can see this defined on LS too. Now the cells are all unique, and not one will have the same properties as the other. Bad, but true. The art as I'm seeing is allowing the pack to get very low, and apply a light load to force it to flow power across the pack. Serial connection should assist, along with the bleeding of the control circuitry inter-cell. Now I have noticed the cells voltages are slowly becoming closer the more I repeat this. It's actually balancing the pack, and the weakest will not be far from the strongest one. I'm trying to figure out if the pack continues to attempt equilibrium when the car is turned off. In which case that may explain and give indication of how long a pack can stay viable. Now I also note the pack on 100%(not seen it yet in reality), as it nears charge completion begins to equalise the cells at this point too. Now how effective it can be depends largely on the power the inter-cell bleed circuitry is, and wether it's restricting itself as voltage rises. Cell monitoring and theoretical charge level on Lion cells is derived from its voltage open circuit. The first indication was the wife clearly saying, and proving by the charge level upon return from her 5 day a week, exactly the same route. First acid test is the old seat of the pants dyno as they say. To be clear on this, you have to allow the car to predict range with repetitive, unchanging use. Now the car is all about finished being polished with UV protection, and I will confirm, with a weeks gap between use, and sat idle with the pack at 93% charge all them days ago next week. The hard to avoid variable is the car deciding to charge it's old style lead acid battery on a daily basis to replace power used, and typical lead acid battery self discharge. I am seriously considering a Lion 12v battery. It makes sense a number of ways. Firstly, self discharge is far lower over time. Secondly they are lighter per capacity over lead acid heavy weights. And thirdly, maintenance is next to nil. Avoiding acid leakage, corrosion and no top up, where a AGM may not be interchangeable due to its differing charge voltage required. Any weight loss will increase power to weight ratio!. Now bear in mind I don't have a bench pack, my testing is live vehicle only. If I damage my previously 72% SOH pack irreversibly, I carry the can for it. However I am very pleased with the results this far, and it pleases the Ministry of War & Finance too!. Remember I cannot be responsible for any damage or inconvenience caused by duplicating my experiments here. I'm simply documenting findings and discoveries about the power supply system in my Leaf. I await a CAN BUS adapter so I can dig deeper into the mystery box, and hopefully help or add info for others to consider. Quick disclaimer I have to write am afraid. Degradation is imposed on the pack as well as it is physically evident. One could call it stretching the pack back out. It's a way used in NIMH cells to bring them back following control circuitry slowly shutting them down. Charging any cells is the enemy of them if it doesn't have the very delicate touch. A Lion battery can be easily charged with DC, but the current and voltage has to be sampled and adjusted to suit many factors. That's the difficult part. There is by the norm, a weakness in charging and balancing a serial connected battery, and the err to safety with respect to longevity is an in-built downward spiral. I have seen countless bad cells be resurrected. I still have my famous three, which are now back in use.... And no problems charging or discharging. Most would recycle them and buy replacements. But I have spotted a way to revive them. Interesting to say the least when documentation states it cannot happen. They came from a faulty PC battery, which in theory was charge controlled. Now ponder this. What if they could last far longer, would this affect production figures in the short run, and cash flow in the manufacturing of them?. Would or could the vehicle or item have a built in degradation program along side natural degradation. It certainly appeared to be the case with Prius HV batteries. Most fail around the 140-175 thou km point!. Odd, but driving habits are different!. I had one cell fail in one battery module in our '06 Prius. When one begins to fail, it propagates across the whole pack if not caught in time. I was lucky and spotted a slight anomaly, and acted immediately. That one cell in one module failed, like many things do in the public market place, that's life. That pack didn't have such a complex inter-cell balance bleed off system that's found in the LEAF, if it had, it would still have failed in my opinion. One day good, next day failed. Rip the pack apart, charge all to 50%, including the replacement module. All together, and good for another few hundred thousand Kms now. The more advanced the pack, the better the watchdog system will be in theory Don't confuse any of this with natural chemical changes in the cell itself. It's pretty complex stuff. I will take time to jot down my findings for certain. There may be inaccuracies too, but information shared is always good. More to come.
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Post by jake on Nov 29, 2016 9:32:49 GMT 11
Since I started this thread, I wanted to repost here stating that after a year of owning the Leaf and my observations of battery life of other owners, I have changed my mind about the order of degradation factors. I now think they are in this order from the most to least.
1. Heat 2. Age 3. Leaving at 0% or 100% 4. Cycling
Heat remains the main enemy of the Leaf battery while it seems aging of the battery affects it much more than I thought. Cycling goes to the bottom of the list as it seems there are enough cycles in the battery to last the cars lifetime.
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Post by 4wardthinking on Nov 30, 2016 17:52:43 GMT 11
Heat is the dangerous facet. It's a bad aspect of charging.. it produces thermo-chemical heat which isn't a pleasant side-effect. I do wonder why Nissan missed this. ...or did they?. Many reasons spring to mind. It's almost certain now that heat is the number one cell killer. Maybe there is a reason to allow this to take place, Post sale money making is next to zero on the likes of a LEAF, so maybe consciously creating a "life-span" may be intentional. The dangerous thing is people will be taking a spanner to a failed pack, with fatally limited high voltage DC knowledge.
I now wait as the nine bar summer inflicted rot approaches. .....but nothing moving as yet. The previously mooted 3% loss has shown itself, yet the car with its mundane, repetitive daily route still reaps the distance, sometimes marginally better. Odd. Either way, the whole "worthless" with any battery reduction appears to be adverse propaganda. If distance is the thing, then a train, plane or coach is the thing. The car simply takes less power if it can't use it, no problems for our normal use, now or in the future I can foresee. As a percentage, most local travel has little limitation. The Prius has a 45 litre tank, but it's only been used in total a few times in seven years, normally lasts a few weeks as a rule. The mind-set of owners "needing", but not actually doing 800km on their Chelsea tractor run requires something, not the car itself. It must be a hard 15 second task to simply plug the car in for some I guess.
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Post by Feng on Jan 13, 2017 16:36:05 GMT 11
So how's everyone coping with the heat? I didn't think it would impact my car but it's definitely causing problems. My air conditioner has been cutting out and I'm getting overheat errors using my OBDII dongle. Might be related to the front end repairs I had a few years ago. My battery capacity is also declining slowly. It's now at 45.43Ahr (69%). Lose another two Ahr or so before 15,000kms and I'll qualify for warranty.
After Leslie's experience I'm hesitant to have it off the road for so many months. On the other hand if I get a new battery pack I would be incredibly happy about it. One can dream!
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Post by 4wardthinking on Jan 13, 2017 18:46:02 GMT 11
IT doesn't have to be off the road so long. All you do is see them, arrange a repair period(days), and pick it up refreshed. The car, like many other premium products on the market, is clearly defined under consumer law. As an owner, you have the right to demand a timely repair period. This doesn't extent to weeks on end. The lack of resource from the dealer doesn't give them right to take their time. If the rest of the world takes less than a week, there is no logical reason it should not here.
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Post by 4wardthinking on Jan 13, 2017 18:48:29 GMT 11
So how's everyone coping with the heat? I didn't think it would impact my car but it's definitely causing problems. My air conditioner has been cutting out and I'm getting overheat errors using my OBDII dongle. Might be related to the front end repairs I had a few years ago. My battery capacity is also declining slowly. It's now at 45.43Ahr (69%). Lose another two Ahr or so before 15,000kms and I'll qualify for warranty. After Leslie's experience I'm hesitant to have it off the road for so many months. On the other hand if I get a new battery pack I would be incredibly happy about it. One can dream! I was of the impression it's nine bars or less was definitive repair. Someone may correct me if I'm wrong. A question here. Did you have the software change done?. If you are not seeing A/C errors, I'd see it as normal operation. The test is 20degrees below ambient at the dash center vent. Overheat alarm is usually the radiator at the front has an obstruction to cross-airflow. Another is the fans that drag the sir through too. I, or another may wish to check the comparative operation on theirs to see if their multispeed fan works at what temperatures. It could be a fault or not connected fan too, after the repairs, it's just a guess Have a look in and behind there first, then flick back. I'll try to resurrect the Nissan Diagnostics in the next few weeks, and see if it will be more specific when I try to do this on our leaf.
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ant
EV Enthusiast
2012 Leaf, EV enthusiast, AEVA WA Secretary
Posts: 43
LEAF OWNER?: Yes
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Post by ant on Jan 15, 2017 3:03:16 GMT 11
Well, having mastered the Prius module adverse propaganda, I feel I should now have a go at dispelling the mist surrounding the Lithium power pack used in the LEAF. Firstly, I carried out an experiment on LiOn 18650's I have an abundance of. I have them sat charged to 95%, which is slightly higher than achievable on a Leaf pack due to its self protection algorithms incorporated in the vehicle. I sat down for weeks testing, charging and loading them. Eventually I weeded out the weak & no-go ones. I placed the 0.4v items in a poly box some 18 months ago, and almost left them until recently, I had occasion to 're-discover' them as I was looking for a few to replace sad ones in an appliance we have. The up-shot is I decided to experiment with three in particular. These over heated, and generally failed all use ability openings in the past. So, I prodded and poked them, and with very little a do, now had them holding charge. I then set out with an intelli charger to push them to a point where they would absorb no more power past the heat producing curve exhibited by them under complete absorption. I then set out to load them to test their output measured carefully. Result was first pass gave 2500mAh. Not bad for a rated cell of 2600mAh. These are a reputable cell manufacturers item, so I have little doubt on their official rating, although I accept that no two cells are identical. I recreated the same conditions, applied the same methodology, and came up with the same results. Off I did the same procedure once more, and a similar result was noted. Odd!, possibly, but consider many reasons why I had been inundated with statements and forecasts in the past years, but I, as per usual, set out to test the claims. I have them sat right beside me now, laid idle for 4 weeks. They have not exploded, bulged, gassed, generated any kind of heat. I monitor them with an IR thermometer twice daily. So, there's an interesting result to say the least. Now I don't have to buy more..... To follow. A documented test of the Leaf power pack. Bought with 74% SOH showing on LeafSpy. Things are changing in this already in my first pass of evaluation. I am not!. For the Nissan Warranty Spies!!, doing anything un-toward to the pack. I note the system attains its SOH based upon "useable" absorption and capacity, which is now in my mind directly related to the "Gid". I am close to establishing its real annotation, and what it is indicating. I will continue in another thread when I have tested the theory. I also am forming a way to increase the "aging" packs potential. Interesting times ahead. When I have proof, I will do a write-up for all to consider. Keep waving at the fossil Servo's guys!. Have you managed to improve your SOH with your efforts? I note that mine remains on 78% - first measured in June 2016
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ant
EV Enthusiast
2012 Leaf, EV enthusiast, AEVA WA Secretary
Posts: 43
LEAF OWNER?: Yes
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Post by ant on Jan 15, 2017 3:06:10 GMT 11
So how's everyone coping with the heat? I didn't think it would impact my car but it's definitely causing problems. My air conditioner has been cutting out and I'm getting overheat errors using my OBDII dongle. Might be related to the front end repairs I had a few years ago. My battery capacity is also declining slowly. It's now at 45.43Ahr (69%). Lose another two Ahr or so before 15,000kms and I'll qualify for warranty. After Leslie's experience I'm hesitant to have it off the road for so many months. On the other hand if I get a new battery pack I would be incredibly happy about it. One can dream! I was of the impression it's nine bars or less was definitive repair. Someone may correct me if I'm wrong. A question here. Did you have the software change done?. If you are not seeing A/C errors, I'd see it as normal operation. The test is 20degrees below ambient at the dash center vent. Overheat alarm is usually the radiator at the front has an obstruction to cross-airflow. Another is the fans that drag the sir through too. I, or another may wish to check the comparative operation on theirs to see if their multispeed fan works at what temperatures. It could be a fault or not connected fan too, after the repairs, it's just a guess Have a look in and behind there first, then flick back. I'll try to resurrect the Nissan Diagnostics in the next few weeks, and see if it will be more specific when I try to do this on our leaf. I asked for documentation for warranty since I don't have anything - Nissan Aus wrote the following: Nissan Motor Co. (Australia) Pty Ltd are pleased to advise the Lithium-Ion battery in your Nissan Leaf vehicle is warranted against capacity loss below nine (9) bars as indicated on the vehicles battery level gauge for a period of 60 months or 100,000 km’s, whichever occurs first. This newly expanded limited warranty covers (free of charge) any repairs needed to return battery capacity to a level of nine remaining bars on the vehicles battery level gauge. If possible, the Lithium-ion battery will be repaired and the original Lithium-Ion battery returned to the vehicle, otherwise, the battery will be replaced.
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Post by 4wardthinking on Jan 15, 2017 8:43:32 GMT 11
Well, having mastered the Prius module adverse propaganda, I feel I should now have a go at dispelling the mist surrounding the Lithium power pack used in the LEAF. Firstly, I carried out an experiment on LiOn 18650's I have an abundance of. I have them sat charged to 95%, which is slightly higher than achievable on a Leaf pack due to its self protection algorithms incorporated in the vehicle. I sat down for weeks testing, charging and loading them. Eventually I weeded out the weak & no-go ones. I placed the 0.4v items in a poly box some 18 months ago, and almost left them until recently, I had occasion to 're-discover' them as I was looking for a few to replace sad ones in an appliance we have. The up-shot is I decided to experiment with three in particular. These over heated, and generally failed all use ability openings in the past. So, I prodded and poked them, and with very little a do, now had them holding charge. I then set out with an intelli charger to push them to a point where they would absorb no more power past the heat producing curve exhibited by them under complete absorption. I then set out to load them to test their output measured carefully. Result was first pass gave 2500mAh. Not bad for a rated cell of 2600mAh. These are a reputable cell manufacturers item, so I have little doubt on their official rating, although I accept that no two cells are identical. I recreated the same conditions, applied the same methodology, and came up with the same results. Off I did the same procedure once more, and a similar result was noted. Odd!, possibly, but consider many reasons why I had been inundated with statements and forecasts in the past years, but I, as per usual, set out to test the claims. I have them sat right beside me now, laid idle for 4 weeks. They have not exploded, bulged, gassed, generated any kind of heat. I monitor them with an IR thermometer twice daily. So, there's an interesting result to say the least. Now I don't have to buy more..... To follow. A documented test of the Leaf power pack. Bought with 74% SOH showing on LeafSpy. Things are changing in this already in my first pass of evaluation. I am not!. For the Nissan Warranty Spies!!, doing anything un-toward to the pack. I note the system attains its SOH based upon "useable" absorption and capacity, which is now in my mind directly related to the "Gid". I am close to establishing its real annotation, and what it is indicating. I will continue in another thread when I have tested the theory. I also am forming a way to increase the "aging" packs potential. Interesting times ahead. When I have proof, I will do a write-up for all to consider. Keep waving at the fossil Servo's guys!. Have you managed to improve your SOH with your efforts? I note that mine remains on 78% - first measured in June 2016 It's interesting to say the least. Your(and many others) quote relating to heat is a facet I'm testing at present. Our LEAF is getting out in the 40 degree heat, and the only modules I can pick that are weaker are showing themselves more clearly than others. The % of capacity has held steady now since July. The anoted Hx has a little variance, but it remains to be demonstrated heat affects it much beyond a few digits. I'm aiming to prose the LEAF from the wife's hands to take it to the Gong for a number of fast charges now the intrepid explorers have charted it. Is there a correlation between FC & any possible correlation, or do dendrites get 'fizzled' away at higher rates of charging is my next part of the puzzle. But to answer the question, the charge capability hasn't changed since I prodded it back to 74%. It makes me wonder what the previous owner did that I am not, that caused the initial 25% drop. The figure was 5% every 6 months, yet it has abated aparrently since July?. Since owning, the 39 DCFC's recorded has not changed.
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Post by duncan on Feb 5, 2017 6:55:16 GMT 11
So how's everyone coping with the heat? I didn't think it would impact my car but it's definitely causing problems. My air conditioner has been cutting out .... Interesting you should mention.....ours cut out once the other day too, very hot day. AC was on but not cooling the air and also not drawing any power. Turned it off for a couple of minutes, restarted and it was OK again, but we are taking it to nissan next week
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