LeftieBiker
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Delivery Date: 30 Apr 2018
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Re: Replace small 12v battery to regular one.

Sat Apr 13, 2019 12:05 pm

Leaf and many modern vehicles charge 12V battery to very optimal state of charge, around 80%.


Lead-acid batteries like to be at 100% state of charge, or as close to it as possible. 80% may be good for a lithium battery, but 80% on a LA battery will cause gradual but significant sulfation.
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.

arnis
Posts: 948
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Leaf Number: 015896
Location: Estonia, Europe

Re: Replace small 12v battery to regular one.

Sat Apr 13, 2019 1:35 pm

Correct. Though charging to this high state of charge results in excessive gassing (electrolyte loss - aka water boils out).
Salt deposition starts at around 60%.
Keeping charging voltage up to around 80% state of charge does not result in excessive gassing.
Ideal window is narrow though definitely doable.
Short range EVs <30kWh -- Medium range: 30-60kWh -- Long range: >60kWh
Charging: Trickle <3kW -- Normal 3-22kW -- Fast 50-100kW -- Supercharging >100kW

powersurge
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Joined: Wed Oct 21, 2015 10:24 am
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Location: Long Island, NY

Re: Replace small 12v battery to regular one.

Wed Apr 17, 2019 6:28 am

I don't seem to see the need to worry about the 12V battery. After 4+ years and 55K miles, my battery is perfectly happy with good voltage numbers. I don't see the 12v battery to be a "maintenance" concern for most drivers. Also, if you put the battery on a "battery tender", then you really will not have issues......

BUT....... You should open the battery and check the water level on the cells regularly... That will kill the Bat.

arnis
Posts: 948
Joined: Sat Jan 23, 2016 3:21 pm
Delivery Date: 23 Jul 2014
Leaf Number: 015896
Location: Estonia, Europe

Re: Replace small 12v battery to regular one.

Thu Apr 18, 2019 7:22 am

Only if cells can be opened. Valve regulated battery with 13.0V charging voltage will not let electrolyte to evaporate nor boil even in hot weather.
Short range EVs <30kWh -- Medium range: 30-60kWh -- Long range: >60kWh
Charging: Trickle <3kW -- Normal 3-22kW -- Fast 50-100kW -- Supercharging >100kW

LeftieBiker
Moderator
Posts: 11337
Joined: Wed May 22, 2013 3:17 am
Delivery Date: 30 Apr 2018
Location: Upstate New York, US

Re: Replace small 12v battery to regular one.

Thu Apr 18, 2019 1:02 pm

arnis wrote:Only if cells can be opened. Valve regulated battery with 13.0V charging voltage will not let electrolyte to evaporate nor boil even in hot weather.


The North American Leaf 12 volt batteries use flooded cells that can (and should, annually) be opened.
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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