Leaf Spy AHr max by battery size

[SageBrush]

I didn't know that AGM are low resistance compared to OEM. Is that generally true for AGM or more specific to the one you used ?

I'm mostly interested for my Tesla. I have this notion that the periodic high vampire drains I see in the car are related to slow 12v charging events from the traction battery. I'm guessing that the car is awake during these 12v charging sessions and consuming 200 - 300 watts.

 

[LeftieBiker]

AGM batteries generally have lower resistance. I don't know why, exactly.

 

[SageBrush]

AGM batteries generally have lower resistance. I don't know why, exactly.

Presumably plate thickness, or the glass is a lower resistance than the plate material used in standard PbA. One way or another the ion path has to be shorter or through less dense substance.

I don't think I've ever read resistance measurements in the specs. Is there a spec that correlates ?

 

[DaveinOlyWA]

Yep. To compare, I put a 4 amp charger on it and it took about 3-4 mins to get to 50%, an additional 13 mins to get to 75%

So this past Friday, I check the battery and its 11.88 volts so I put the charger on and this time it took 6 mins to get to 25% (My charger only increments 25%) and another 13-15 mins (sorry didn't stand out there watching it) to get to 50% so yeah; for the most part, the battery is barely surviving most of the winter.

I don't think your measurements make sense.

A new battery is around 40 Ahr
You are talking about ~ ONE Ahr capacity

Perhaps you are measuring surface charge. Gerry will know

Agreed. My guess its the meter on the charger. While charging I noticed voltage at the battery started out around 14.15 volts eventually rising to 14.54 volts. Granted its a different charge parameter but 3 times I charged to full, it took hours to go from 75% to full.

I went back to LS logs and found that charging voltage was only 14.15 volts on startup. Previously w/o charging the 12 volt externally, it was always 14.54 volts so the charging is doing something.

On the AGM thing; iirc the glass mat format allows more even distribution of electrons making the jump from one to another more uniform which is reason why resistance is lower. If my current battery fails, I am likely to just get Li. Yeah, its currently 3X the cost at least but I know a handful who have had theirs 5+ years and no issues whatsoever.

 

[SageBrush]

If my current battery fails, I am likely to just get Li. Yeah, its currently 3X the cost at least but I know a handful who have had theirs 5+ years and no issues whatsoever.

Is your PbA not lasting in the cool NW climate ? I think all you really need is a deep cycle PbA

My interest in a Li battery is for my Tesla. It has ~ a 6 watt vampire drain, and I'd like the battery to have enough capacity to provide 48 hours of vampire drain before the car wakes up to charge the 12v. Alternatively, I can shop for a low resistance PbA so that the charging episode is brief(er). Ideal would be high capacity, fast charging but I don't know if that exists.

Tesla recently announced that Model S and Model X are now being equipped with Li 12v batteries. I'm hopeful that the Model 3 gets to join hte party.

 

[LeftieBiker]

AGM batteries generally have lower resistance. I don't know why, exactly.

Presumably plate thickness, or the glass is a lower resistance than the plate material used in standard PbA. One way or another the ion path has to be shorter or through less dense substance.

I don't think I've ever read resistance measurements in the specs. Is there a spec that correlates ?

Not that I know of. The reason isn't the plate thickness: if the plates were thinner it would be a starting battery rather than a deep cycle battery, as thick plates provide more amps but have a shorter cycling life. I think Dave is probably right about the glass mat, but don't know for sure.

 

[DaveinOlyWA]

If my current battery fails, I am likely to just get Li. Yeah, its currently 3X the cost at least but I know a handful who have had theirs 5+ years and no issues whatsoever.

Is your PbA not lasting in the cool NW climate ? I think all you really need is a deep cycle PbA

My interest in a Li battery is for my Tesla. It has ~ a 6 watt vampire drain, and I'd like the battery to have enough capacity to provide 48 hours of vampire drain before the car wakes up to charge the 12v. Alternatively, I can shop for a low resistance PbA so that the charging episode is brief(er). Ideal would be high capacity, fast charging but I don't know if that exists.

Tesla recently announced that Model S and Model X are new being equipped with Li 12v batteries. I'm hopeful that the Model 3 gets to join hte party.

Well, its my belief my battery has lost over half its capacity. I will be putting it on the charger more in the next few days as we are expected to be in the 20's for most of the week before the snow slams us. Previously, the lowest readings I ever saw was 12.15ish so these 11 volt readings are shocking to me. I have to think the wi fi connection is the culprit. I am in a different location but the temperature ranges are actually appearing to be a few degrees warmer in the new location based on OAT. Right now garage is 56.3º OAT is 31º. The old location would be around 54ish or so.

My first thought was to milk the battery as long as possible and replace with AGM since is DoD is considerably larger but am seeing too many reports of AGM's failing after 2 years or less so??

 

[SageBrush]

My first thought was to milk the battery as long as possible and replace with AGM since is DoD is considerably larger but am seeing too many reports of AGM's failing after 2 years or less so??

Deep cycle, AGM sounds to me like a good solution for the LEAF.
Know any good candidates ?

Back in our Prius days the Optima battery was touted and I had a good experience with it. I also think @GerryAz uses them. I've been hesitating, in part because I read (admittedly some years ago) about quality problems, and because they are expensive.

 

[LeftieBiker]

Supposedly the issues with Optimas, which seemed to be related to sending production to Mexico, have been resolved. I would avoid any Chinese brand AGM batteries.

 

[GerryAZ]

I have been using Optimas in all of my vehicles that they fit. Red Top batteries for ICE starting applications and Yellow Top deep cycle D51R size for LEAFs. I will purchase a D51R Yellow Top for the 2019 LEAF as soon as the OEM battery begins to show weakness, but it seems to be OK for now. I have always had much longer life from Optimas than flooded cell batteries and have not yet had a premature failure. Please be aware that sustained overcharging of any AGM will greatly shorten its life.

 

[SageBrush]

I'd like to hear opinions about
https://www.remybattery.com/intimidator-9a34r-battery.html

This is a 34R, deep cycle, AGM battery
Other threads have mentioned using this battery size in the LEAF with Rogue parts (tray, anchor pieces.)

---
This 51R AGM, dual cycle also looks promising
https://www.remybattery.com/batteries/intimidator-9a51r-group-size-51r-agm-battery-html.html
$170 - 10% discount code if email provided, and free shipping. Part of the 'DEKA' line, manufactured by E Penn

 

[LeftieBiker]

I'd like to hear opinions about
https://www.remybattery.com/intimidator-9a34r-battery.html

This is a 34R, deep cycle, AGM battery
Other threads have mentioned using this battery size in the LEAF with Rogue parts (tray, anchor pieces.)

---
This 51R AGM, dual cycle also looks promising
https://www.remybattery.com/batteries/intimidator-9a51r-group-size-51r-agm-battery-html.html
$170 - 10% discount code if email provided, and free shipping. Part of the 'DEKA' line, manufactured by E Penn

The first one isn't optimum for a Leaf, because it sacrifices some life for starting amps that you don't need. Unless you plan to jump start other vehicles, I'd go for a deep cycle AGM battery. Of course any genuine AGM battery will likely be a big improvement...and the second one seems to be the same deal, but with the correct terminals. I'd get an AGM automotive battery with the longest warranty and the greatest capacity in a 51R size and configuration.

 

[SageBrush]

I'd like to hear opinions about
https://www.remybattery.com/intimidator-9a34r-battery.html

This is a 34R, deep cycle, AGM battery
Other threads have mentioned using this battery size in the LEAF with Rogue parts (tray, anchor pieces.)

---
This 51R AGM, dual cycle also looks promising
https://www.remybattery.com/batteries/intimidator-9a51r-group-size-51r-agm-battery-html.html
$170 - 10% discount code if email provided, and free shipping. Part of the 'DEKA' line, manufactured by E Penn

The first one isn't optimum for a Leaf, because it sacrifices some life for starting amps that you don't need.

Am I wrong to think that CCA correlates with capacity, all else being equal ? That 34R is 44 Lb

 

[GerryAZ]

CCA is not necessarily proportional to Ah. I just looked at Optima's web site. They don't have the Red Top in 51R size so comparing size 34/78 we have: Red Top (starting battery) 38.80 lbs, 50.00 Ah, and 800 CCA; Yellow Top (deep cycle) 43.50 lbs, 55.00 Ah, and 750 CCA. These numbers illustrate the difference between deep cycle and starting with the deep cycle capable of delivering more current at a low discharge rate, but less cranking current.

 

[GerryAZ]

I made some 12V battery measurements to compare with Dave's numbers. I started my Leaf and drove 6 miles to my workshop garage this morning. I parked, turned off the Android device which runs Leaf Spy Pro, left the Bluetooth adapter plugged in to the OBDII port, released the hood, and locked the car at 8:15 AM. The battery voltage was 12.710 at 10:30 AM, 12.622 at 4:30 PM, and 12.598 at 6:30 PM. Therefore, it appears that my car is keeping its 12V battery adequately charged after 18 months of use without external charging and without any special actions--just normal driving and L2 charging.

 

[DaveinOlyWA]

I made some 12V battery measurements to compare with Dave's numbers. I started my Leaf and drove 6 miles to my workshop garage this morning. I parked, turned off the Android device which runs Leaf Spy Pro, left the Bluetooth adapter plugged in to the OBDII port, released the hood, and locked the car at 8:15 AM. The battery voltage was 12.710 at 10:30 AM, 12.622 at 4:30 PM, and 12.598 at 6:30 PM. Therefore, it appears that my car is keeping its 12V battery adequately charged after 18 months of use without external charging and without any special actions--just normal driving and L2 charging.

Well, I was seeing the same last summer. I never check the voltage less than 10-12 hours after driving or charging (usually first thing in morning) but I was seeing 12.35 - 12.55 range quite consistently. I didn't check the battery last Winter so don't know how low it got but hoping I see a few tenths rebound when the weather warms up.

My next wrinkle will be disabling Wifi to see if that changes anything. The likelihood I will miss an update seems rather...remote.

 

[SageBrush]

CCA is not necessarily proportional to Ah. I just looked at Optima's web site. They don't have the Red Top in 51R size so comparing size 34/78 we have: Red Top (starting battery) 38.80 lbs, 50.00 Ah, and 800 CCA; Yellow Top (deep cycle) 43.50 lbs, 55.00 Ah, and 750 CCA. These numbers illustrate the difference between deep cycle and starting with the deep cycle capable of delivering more current at a low discharge rate, but less cranking current.

Emphasis on all else being equal

 

[LeftieBiker]

The main difference between starting and deep cycle batteries is the thickness of the plates. Starting batteries have thinner plates with more surface area, to provide more cranking power. Deep cycle batteries have thicker plates to better withstand sulfation as well as physical shocks, since they are often moved around.

 

[SageBrush]

The main difference between starting and deep cycle batteries is the thickness of the plates. Starting batteries have thinner plates with more surface area, to provide more cranking power. Deep cycle batteries have thicker plates to better withstand sulfation as well as physical shocks, since they are often moved around.

My understanding as well, but take a battery with thin plates and double its capacity. What changes in the CCA ?

 

[LeftieBiker]

How are you doubling the capacity?