VitaminJ
Posts: 396
Joined: Tue Jan 03, 2017 11:46 am
Delivery Date: 07 Jan 2017
Leaf Number: 415775
Location: Morrison, CO
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Re: 12 Volt Lead Acid Battery Replacement

Sat Jan 21, 2017 4:55 pm

Well I got struck by the 12v curse today, Leaf is nonresponsive. I tried jumping it and then switching on the windshield wipers, thinking that triggers the 14.4v DC converter to kick on, but nothing happened. Charging the 12v battery on the bench at the moment, probably going to replace it with a LiFePO. I have about 30 suitable Lipo RC batteries, but the voltage doesn't quite match up, too high for a 3S and too low for a 4S.
2013 Ocean Blue SV w/ QC and LED
- +0.2 mi/kwh Aeromods
- 2lb 5Ah LiFe 12v battery

LeftieBiker
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Location: Upstate New York, US

Re: 12 Volt Lead Acid Battery Replacement

Sat Jan 21, 2017 10:07 pm

Just keep in mind that the issue isn't high current drains, but problematic charging behavior by the car. Even a Lithium battery will get low eventually and have to be recharged, unless the 'capacity theory', which says that higher capacity accessory batteries will be charged adequately by the car, is correct. In either case, a better SLA battery and a maintainer would be much cheaper, and potentially more reliable.
Scarlet Ember 2018 Leaf SL W/ Pro Pilot
2009 Vectrix VX-1 W/18 Leaf modules, & 3 EZIP E-bicycles.
PLEASE don't PM me with Leaf questions. Just post in the topic that seems most appropriate.

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IssacZachary
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Leaf Number: 420789
Location: Gunnison, CO, USA

Re: 12 Volt Lead Acid Battery Replacement

Sun Jan 22, 2017 12:05 am

Anyone putting voltmeters and ammeters on their Leaves? (I'm still not sure if the correct term is Leaves or Leafs.) That would be the way to see if it's the Leaf's charging system or the battery that's goofy.

The most fool proof energy storage would be an ultra capacitor battery with balancers. There are guys doing this on their ICE vehicles and turning out just fine. But it wouldn't hold a lot of charge and could go dead quicker than even a lead acid battery if there were too much drain. At least going dead wouldn't hurt it at all. And yes, the insane amperage that an ultra capacitor can put out isn't necessary in a BEV, but it's the longevity that catches my attention at millions of cycles instead of a few hundred (lead acid) or thousand (lithium).

2013 SL SOLD :cry:
2013 Toyota Avalon Hybrid CURRENT

LeftieBiker
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Location: Upstate New York, US

Re: 12 Volt Lead Acid Battery Replacement

Sun Jan 22, 2017 12:27 am

The most fool proof energy storage would be an ultra capacitor battery with balancers.


It's the BMS that makes lithium packs less reliable. Perfectly good sets of cells get ruined by a malfunctioning BMS. I wouldn't want to test that with ultra-capacitors...

"LEAF" is actually an acronym made up by Nissan, so the plural is "Leafs." As for voltmeters, the problem with installing one is that they are all made in China. Some are accurate, others wildly not. If you get one that tests good, it could at least provide a benchmark.
Scarlet Ember 2018 Leaf SL W/ Pro Pilot
2009 Vectrix VX-1 W/18 Leaf modules, & 3 EZIP E-bicycles.
PLEASE don't PM me with Leaf questions. Just post in the topic that seems most appropriate.

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IssacZachary
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Re: 12 Volt Lead Acid Battery Replacement

Sun Jan 22, 2017 1:18 am

LeftieBiker wrote: It's the BMS that makes lithium packs less reliable. Perfectly good sets of cells get ruined by a malfunctioning BMS. I wouldn't want to test that with ultra-capacitors...


Thanks! Leafs it is!

Now that you mention is, my brother-in-law, who's always wanted to build his own BEV and has a degree in electrical engineering, told me once that it would be much better to bottom balance lithium cells and then manually check them with a good digital multi-meter once in a while than to add a top balancing BMS. The same may be true with the ultra capacitors.
2013 SL SOLD :cry:
2013 Toyota Avalon Hybrid CURRENT

LeftieBiker
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Joined: Wed May 22, 2013 3:17 am
Delivery Date: 31 May 2013
Location: Upstate New York, US

Re: 12 Volt Lead Acid Battery Replacement

Sun Jan 22, 2017 3:40 am

I have a Vectrix VX-1 maxiscooter that was converted by the previous, original owner from the horrible OEM NiMH pack that sank the company, to 18 pairs of Leaf cells. It has no BMS. As long as the cells check out ok in the Spring (there are measuring/balancing leads) voltage-wise, I shouldn't have to worry about a failed BMS, or anything else but heat and low voltage, all season.
Scarlet Ember 2018 Leaf SL W/ Pro Pilot
2009 Vectrix VX-1 W/18 Leaf modules, & 3 EZIP E-bicycles.
PLEASE don't PM me with Leaf questions. Just post in the topic that seems most appropriate.

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Stanton
Posts: 2097
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Leaf Number: 7458
Location: Plano, TX
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Re: 12 Volt Lead Acid Battery Replacement

Sun Jan 22, 2017 8:24 am

If you really want to "get the lead out" for the 12v battery, why don't you just replace it with a LiFePO4 made for that purpose (BMS included)? There's a whole thread on it http://www.mynissanleaf.com/viewtopic.php?f=37&t=11999
2011 Blue Ocean SV w/floor mats & window tint
12v LiFePO4 battery & FIAMM 74100 horns
Wet Okole seat covers (front)
Tor's low-power heater mod
2013 sun visor
3G modem upgrade
L2 EVSE Upgrade
Battery Pack replaced (Rev E) @51 months and 41k miles

VitaminJ
Posts: 396
Joined: Tue Jan 03, 2017 11:46 am
Delivery Date: 07 Jan 2017
Leaf Number: 415775
Location: Morrison, CO
Contact: YouTube

Re: 12 Volt Lead Acid Battery Replacement

Sun Jan 22, 2017 9:37 am

The Leaf already has a voltmeter on the 12v battery, you can see it in Leaf Spy.
2013 Ocean Blue SV w/ QC and LED
- +0.2 mi/kwh Aeromods
- 2lb 5Ah LiFe 12v battery

LeftieBiker
Posts: 9418
Joined: Wed May 22, 2013 3:17 am
Delivery Date: 31 May 2013
Location: Upstate New York, US

Re: 12 Volt Lead Acid Battery Replacement

Sun Jan 22, 2017 1:16 pm

VitaminJ wrote:The Leaf already has a voltmeter on the 12v battery, you can see it in Leaf Spy.


That's true. It would be convenient, though, to have one that can be read instantly, without having to connect LeafSpy.
Scarlet Ember 2018 Leaf SL W/ Pro Pilot
2009 Vectrix VX-1 W/18 Leaf modules, & 3 EZIP E-bicycles.
PLEASE don't PM me with Leaf questions. Just post in the topic that seems most appropriate.

joeriv
Posts: 166
Joined: Sun Mar 24, 2013 1:33 pm
Location: Fairfield County CT

Re: 12 Volt Lead Acid Battery Replacement

Sun Jan 22, 2017 7:24 pm

For about $12 you can get a battery analyzer that plugs into the 12 volt accessory port. I bought the Innova 3721 on Amazon and it works great.
2017 Leaf S with QC, JUN mfg date

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