Help please: 2019 SL+ won't start in garage after charge
- Thread starter frontrangeleaf
- Start date
Help Support My Nissan Leaf Forum:
I welcome a discussion, but that is different than feeling obliged to counter 'LFP is great in the LEAF!' posts that do not bother to clarify weather gotchas. I'm not saying LFP without thermal control in below freezing temps is dangerous, I'm saying it is not suitable for cold weather climates.knightmb said:
Color me skeptical on that claim. There is a lot more power drain on the 12v than just starting up the car.
knightmb
Well-known member
I'll start a topic about it, I feel like I'm hijacking this topic. :lol:
To the OP, I agree with everyone here, go with a good quality AGM as it's a one and done for replacement.
To the OP, I agree with everyone here, go with a good quality AGM as it's a one and done for replacement.
SageBrush said:
frontrangeleaf
Well-known member
LeftieBiker said:
They advertise this as non-spillable, for vehicles with high electrical demands and start/stop technology, with 2x the life of a flooded battery. All of which suggests to me it really is an AGM in some reasonable sense. CCAs are notably lower than their next level down 'gold' battery, which I welcomed.
Perhaps not of the same quality as a yellow top Optima, but I couldn't find one of those locally, and they were about $70 more.
I haven't really seen this noted but marine batteries aren't necessarily AGM batteries although they are probably better suited for a Leaf that needs more reserve capacity at the expense of higher CCA and they might also be able to handle lower voltages? Not sure if you can find a 51R size in a marine battery though as they tend to be larger sized(group 27 if memory serves me) and way too big to fit in a Leaf. Last time I was at a store that sold 12v batteries it seemed to me all the "marine" batteries were AGM but I'm pretty sure that wasn't always the case and marine batteries had liquid acid just like regular automotive batteries.
Marine batteries used to be starting type, but with somewhat thicker plates. No idea now.
frontrangeleaf
Well-known member
My understanding for flooded batteries is as follows:
Starter batteries optimized for very short duration (dozens of seconds) @ very high current output. Translates to more numerous thinner plates to maximize surface area. Will not tolerate deep cycling, as the thin plates rapidly degrade when chemically stressed. Some level of permanent damage can result from even a single complete discharge, as I understand matters, although the battery may continue to start your car as long as it's not too cold out, etc.
True deep cycle batteries are on the other end of the spectrum, with fewer thicker plates more resistant to unwanted physical degradation in deeper cycles (down to 50% SoC). These are also known as "golf cart" or RV "house" batteries. The battery we purchased for our camper is of this type (travel trailer, no need to start an engine). Not a starter battery. Does not have a CCA rating. Also has a different chemistry (has antimony alloy in the plates).
"Marine/RV" batteries are a hybrid in between the 2 types above, with some ability to start boat and RV engines combined with more longevity when cycled somewhat deeper (80% SoC IIRC). Most so-called "deep cycle" batteries are of this type. The give away is a CCA claim. If they make one, it's not a true deep cycle, it's a hybrid.
I have no idea how the above maps onto the AGM world, but I imagine it would parallel the above.
The battery we bought for our Leaf is a hybrid, likely. Almost certainly an AGM as noted earlier.
AGMs would be useful on a boat because they're spillproof. Also used in off-road vehicles driven at high-angles (very steep inclines). Our Audi, although not an off-road vehicle per se, is rated to grades up to 30% in part because it has an AGM battery. The other consideration is the oil pump sump, which needs to be properly baffled so that it doesn't suck air at high inclines.
If I'm following along properly, the main reason we recommend AGM batteries for the Leaf is that they resist sulfation due to low charge, largely because they don't stratify the way a flooded battery does when left sitting at low charge. That, and they're more affordable that lithium, at least for now.
Starter batteries optimized for very short duration (dozens of seconds) @ very high current output. Translates to more numerous thinner plates to maximize surface area. Will not tolerate deep cycling, as the thin plates rapidly degrade when chemically stressed. Some level of permanent damage can result from even a single complete discharge, as I understand matters, although the battery may continue to start your car as long as it's not too cold out, etc.
True deep cycle batteries are on the other end of the spectrum, with fewer thicker plates more resistant to unwanted physical degradation in deeper cycles (down to 50% SoC). These are also known as "golf cart" or RV "house" batteries. The battery we purchased for our camper is of this type (travel trailer, no need to start an engine). Not a starter battery. Does not have a CCA rating. Also has a different chemistry (has antimony alloy in the plates).
"Marine/RV" batteries are a hybrid in between the 2 types above, with some ability to start boat and RV engines combined with more longevity when cycled somewhat deeper (80% SoC IIRC). Most so-called "deep cycle" batteries are of this type. The give away is a CCA claim. If they make one, it's not a true deep cycle, it's a hybrid.
I have no idea how the above maps onto the AGM world, but I imagine it would parallel the above.
The battery we bought for our Leaf is a hybrid, likely. Almost certainly an AGM as noted earlier.
AGMs would be useful on a boat because they're spillproof. Also used in off-road vehicles driven at high-angles (very steep inclines). Our Audi, although not an off-road vehicle per se, is rated to grades up to 30% in part because it has an AGM battery. The other consideration is the oil pump sump, which needs to be properly baffled so that it doesn't suck air at high inclines.
If I'm following along properly, the main reason we recommend AGM batteries for the Leaf is that they resist sulfation due to low charge, largely because they don't stratify the way a flooded battery does when left sitting at low charge. That, and they're more affordable that lithium, at least for now.
Two other things to note: the AGM batteries may work better with the Leaf's charging system because they accept a higher amperage charge more readily, and the car seems to be programmed to give them that. This why there is speculation that the Leaf was originally designed to have a lithium accessory battery. And as I understand it, the glass fibers are there in a high enough density to physically inhibit the growth of large sulfate crystals.
i can't find any information that supports higher current for AGM, in fact just the opposite:
From what i found online, the typical standard AGM charging rate seems to be 0.1C, so for a 35Ahr battery that would be 3.5 Amps; with a maximum rate of 0.2 to 0.3C depending upon manufacturer, but seems to be not recommended except for time-critical situations.
The internal resistance is related to the rate of the chemical reaction in the cells, the biggest factor is temperature; but its still the same lead+sulfuric acid chemical reaction in all of them.
The laef seems to be set up to charge AGM without damage to them, but the compromise is that it is somewhat insufficient to maintain flooded cell batteries such as an ICE car.
From what i found online, the typical standard AGM charging rate seems to be 0.1C, so for a 35Ahr battery that would be 3.5 Amps; with a maximum rate of 0.2 to 0.3C depending upon manufacturer, but seems to be not recommended except for time-critical situations.
The internal resistance is related to the rate of the chemical reaction in the cells, the biggest factor is temperature; but its still the same lead+sulfuric acid chemical reaction in all of them.
The laef seems to be set up to charge AGM without damage to them, but the compromise is that it is somewhat insufficient to maintain flooded cell batteries such as an ICE car.
nlspace said:
Given your bolded statement, have you measured what the Leaf's typical 12V battery charging current is,
i.e. based on various levels of SOC of its 12V battery? More specifically, does the Leaf actually monitor
the charging current or just provide a voltage source for charging?
knightmb
Well-known member
Actually, I might have that answer in this topic: https://mynissanleaf.com/viewtopic.php?f=9&t=32938
Near the bottom of the first page where I posted screen-shots from LeafSpy.
Near the bottom of the first page where I posted screen-shots from LeafSpy.
Learjet
Well-known member
knightmb said:
I'm pretty sure the voltage reduces below ~14.4 to ~13.1 at some amp level of charge, assuming the windshield wipers are not on.
Looking at your screen shot, it may reduce initial charge voltage at 0.5 amps? should be a pretty easy thing to watch leafspy after initial startup and note the amp level when voltage is reduced.
Learjet said:
Right, but what is the peak and average charging current? This appears to be of importance when using an AGM battery in the Leaf,
given comments made up-thread by some about the peak charging current for AGM batteries.
https://www.ayixa.com/how-many-amps-can-you-charge-an-agm-battery-at/
Here's one rated at 41 Ahr; https://www.autozone.com/batteries-starting-and-charging/battery/p/duralast-platinum-agm-battery-51r-agm-group-size-51r-435-cca/229893_0_0
