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Re: The Battery Replacement Thread

Posted: Mon Sep 14, 2015 4:07 pm
by kolmstead
Didn't Nissan remove the capacity vs bars chart from the service manual fairly early on? If so, we don't really know how the math on the 2013-2015 models compares, let alone new 2016.

Haven't tried an endurance run at my "standard" test conditions; the only data I had was from the original run home from Palmdale, CA where I made 84 miles and ended up just a little below VLBW. I do know that my current 100% charge shows 175 GIDS, about 13.6 kWh. I've been getting 45-55 miles to turtle, at around 4.0 mpk.

As far as we know, no-one has gotten a new battery by presenting any data other than 4 bar loss, so I question the utility of doing endurance runs or measuring how much energy it takes to recharge the battery. The warranty only says "less than nine capacity bars" and "less than 70% capacity", with no means given to measure that number.

Re: The Battery Replacement Thread

Posted: Mon Sep 14, 2015 4:24 pm
by fooljoe
kolmstead wrote:As far as we know, no-one has gotten a new battery by presenting any data other than 4 bar loss, so I question the utility of doing endurance runs or measuring how much energy it takes to recharge the battery. The warranty only says "less than nine capacity bars" and "less than 70% capacity", with no means given to measure that number.
We do know of cases of Nissan granting replacements for those who didn't qualify for the warranty in the strict sense. Here's one example.

Obviously it's still early, since we haven't had anybody hit the 5-year mark yet. But it's inevitable that some (perhaps many) will find their warranty expiring while they sit on 9 bars and <70% SOH as reported by LeafSpy. Given Nissan's statements around the 70% number, I think those that "just miss" the warranty could and should fight Nissan to get them to honor their promises; I'm just suggesting a way to collect some evidence for the fight.

Re: The Battery Replacement Thread

Posted: Mon Sep 14, 2015 6:34 pm
by DaveEV
The only consistent way for an end user to prove that the battery has declined to less than 70% capacity is to measure the amount of energy used to charge the car from turtle to 100%. Chargepoint and Blink stations, for example, will measure energy dispensed to the car. Or you can buy a meter from EKM Metering or similar to measure.

One would probably want to repeat this test 2-3x to be sure.

When new, the LEAF takes about 25 kWh from the wall to charge from turtle to 100%. So if your LEAF takes less than 17.5 kWh to charge, you're under 70% capacity remaining.

Re: The Battery Replacement Thread

Posted: Mon Sep 14, 2015 8:14 pm
by kolmstead
Is turtle good enough, or do I need to push on to contactor disconnect? Turtle certainly isn't a problem; I'm hitting that two or three times a week. There's more than one flavor of turtle. I can be very close, say 0.5 or 0.6 kWh remaining, and if I turn off the car and restart it, it comes up turtled at 0.4 or 0.3 kWh remaining. Or I can push it lower as long as I don't restart.

But I don't believe that Nissan would replace my car's battery based on that test.

-Karl (65.9%)

Re: The Battery Replacement Thread

Posted: Mon Sep 14, 2015 9:41 pm
by fooljoe
drees wrote:The only consistent way for an end user to prove that the battery has declined to less than 70% capacity is to measure the amount of energy used to charge the car from turtle to 100%. Chargepoint and Blink stations, for example, will measure energy dispensed to the car. Or you can buy a meter from EKM Metering or similar to measure.

One would probably want to repeat this test 2-3x to be sure.

When new, the LEAF takes about 25 kWh from the wall to charge from turtle to 100%. So if your LEAF takes less than 17.5 kWh to charge, you're under 70% capacity remaining.
The problem with this method is that the overhead from charging is inconsistent. Charging efficiency varies quite a bit depending on the voltage and amperage of the supply (for example L2 is roughly 10% more efficient than L1) and all sorts of other factors like the pack's temperature, internal resistance, and so on.

Plus you'd then be relying on some third party gauge for power consumption, giving Nissan something to point the blame at. Using the efficiency and odometer on the dash may not be the most accurate measures, but if they're wrong that's Nissan's problem.

Re: The Battery Replacement Thread

Posted: Tue Sep 15, 2015 12:16 am
by DaveEV
kolmstead wrote:Is turtle good enough, or do I need to push on to contactor disconnect?
Certainly going all the way to contactor disconnect would be best, but I don't think that level of accuracy is required since there is so little energy available once turtle kicks on, anyway.
kolmstead wrote:But I don't believe that Nissan would replace my car's battery based on that test.
No, certainly not without a fight, anyway.
fooljoe wrote:The problem with this method is that the overhead from charging is inconsistent.
The difference between 208/240V is pretty small, but it should be easy to compensate for.

One should charge on a station that can supply maximum current.
fooljoe wrote:all sorts of other factors like the pack's temperature, internal resistance, and so on.
Temperature can be compensated for, but it resistance doesn't vary by enough to matter at the charging rates.

Internal resistance of the pack is around 0.85 ohms when new at room temperature and around 1.15 ohms at 70% or so.
fooljoe wrote:Plus you'd then be relying on some third party gauge for power consumption, giving Nissan something to point the blame at. Using the efficiency and odometer on the dash may not be the most accurate measures, but if they're wrong that's Nissan's problem.
Obviously one would simply use their data as a starting point - Nissan can supply their own test procedure using their own calibrated test equipment for the final say. But hey, if you have a better idea that one can use to produce consistent results, let's hear it.

So far it seems that you're only option if that 4th bar just won't drop is to drive as inefficiently as possible around while QCing and hope that 4th bar drops before your warranty expires.

Re: The Battery Replacement Thread

Posted: Wed Sep 23, 2015 5:29 pm
by 1932highboy
My new battery has came in and I am getting it installed tomorrow.

Re: The Battery Replacement Thread

Posted: Thu Sep 24, 2015 6:08 am
by pjoseph
After

Before

LeafSpy Screen shots

Re: The Battery Replacement Thread

Posted: Thu Sep 24, 2015 7:18 am
by Stanton
^ ^ ^ what's the (before) AHr reading? Should be 4x.x

Re: The Battery Replacement Thread

Posted: Thu Sep 24, 2015 8:15 am
by mwalsh
Stanton wrote:^ ^ ^ what's the (before) AHr reading? Should be 4x.x
Low - 42.22AHr


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