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Had a client ask what happens if he doesn't use his electric car for a few month, could the battery pack run flat?
My answer was - I don't no, I can install any charge unit you want but as I haven't bought a Nissan nv200e yet I won't no. I said I'll ask the clever guys on a forum.....
Any info gratefully received.
 

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Had a client ask what happens if he doesn't use his electric car for a few month, could the battery pack run flat?
I think most EV's would eventually run the pack flat because they contain monitoring systems that use some energy even when the car is not in use. Tesla recommend their cars are plugged in when not in use and I've used that strategy when traveling for more than six weeks.
 

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Peugeot iON 2013, Renault Zoe 50 2020
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My understanding is that the main traction pack is completely disconnected when the car is switched off. All the systems that stay on when the car is switched off are run from the regular 12V battery, which will eventually go flat under the load.
The vehicle will then require a jumpstart to start, which will bring the main traction pack back into play, which will then recharge the 12V battery.
This info is based on the behaviour of my EV (i-MIEV/iON/C-Zero) and also the behaviour of the Toyota Prius.
The jumpstart doesn't require a huge battery, as there is no starter motor and engine to turn - I have heard of people using rechargeable drill batteries to do it.
 

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When the 12V died (the second time) on the LEAF I charged it for about 5 mins from a Halfords battery charger, that was enough. When they tested it the following week it was at about 70-80% charged (from light daily use).
 

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Just leave it plugged in then no worries, but Renault had my car for 3 months and they did not charge it, it only had 15% when I toke it in. Was still the same when I picked it up. It had to have its inverter replaced
 

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My understanding is that the main traction pack is completely disconnected when the car is switched off
Don't forget that most of the commercial EVs have a Traction Battery Management System that presents a parasitic load at all times so the system is never truly 'switched off' and will discharge overtime... one reason why many in the EV conversion world don't use BMS :)
 

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Don't forget that most of the commercial EVs have a Traction Battery Management System that presents a parasitic load at all times so the system is never truly 'switched off' and will discharge overtime... one reason why many in the EV conversion world don't use BMS :)
Interesting to hear that - I wonder if the BMS is powered from the 12V battery or the traction battery?
If it's powered from the 12V side then maybe disconnecting the 12V battery would be best for storage?
 

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The Leaf periodically charges the 12V battery from the traction battery when turned off so although a Leaf in a switched off state won't drain the traction battery directly the traction battery will discharge over time as it periodically recharges the 12V battery.

I know that the solar panel on the Leaf is a bit of a gimmick but this is the only situation where it actually has some use. The solar panel trickle charges the 12V battery reducing the the need for the traction battery to recharge it. So, if you have a Leaf with the solar panel and it is in the sun during the day then the traction battery should not discharge.
 

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So how have I had two flat 12v battery incidents with a charged traction battery and the solar panel? Grrr.
Very annoying. Sounds like a fault of some kind to me :)

The Leaf should never allow the 12V battery to go flat all the while there is power in the traction battery and with the solar panel it should pretty much guarantee it never goes flat IMO.
 

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Very annoying. Sounds like a fault of some kind to me :)

The Leaf should never allow the 12V battery to go flat all the while there is power in the traction battery and with the solar panel it should pretty much guarantee it never goes flat IMO.
I've apparently missed a call from Nissan today so will try and find out if they're coming around to this rather than the "wait for it to fail and get a flatbed" line so far taken.

Any online documentation relating to the way the LEAF batteries work together? I tried Google but came up empty handed, it'd be very handy to have!
 

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I think there is a section in the manual about it. IIRC the traction battery top-up only while off happens once every 5 days and then only for 5 minutes, so it's possible you can drain the 12v before it even gets a chance.
 

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From the 2011 Leaf Manual...

While the vehicle is not in use
When the EV (Electric Vehicle) system is off, the 12-volt battery charges automatically for 5
minutes every 5 days.

The charge timing resets to 5 days without charging the 12-volt battery if:
. The vehicle is placed in the READY to drive position for more than 5 minutes.
. The Li-ion battery is charged for more than 5 minutes.
So yes, very easy to drain the battery if there is a fault or if the lights left on etc though the 12V charging in this way is for a normal, healthy car in which case the 5 days is probably perfectly adequate.
 

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I see, so no regular "in motion" daily charge ala ICE vehicles? Any docs on the solar panel?

If I seem lazy it's because I'm trapped under a sleeping six year old, afraid of the wrath should I wake her!
 

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I see, so no regular "in motion" daily charge ala ICE vehicles? Any docs on the solar panel?

If I seem lazy it's because I'm trapped under a sleeping six year old, afraid of the wrath should I wake her!
LOL! Please! Too much information! ;)

No worries. I have the manual in PDF format so I can do searches...

From Manual:
While vehicle is driven
The Li-ion battery charges the 12-volt battery as necessary when the power switch is in the
READY to drive position.
So when powered on it charges the 12V as necessary. I have noticed on LeafSpy that this is quite often. I know it is charging when the 12V battery voltage goes up to 13.2V and that happens quite frequently

Re solar....
SOLAR CELL MODULE (if soequipped)
This vehicle uses a solar cell module to provide
power to the 12-volt battery. The solar cell
module only provides power to help maintain the
charge of the 12-volt battery; it will not recharge
a discharged 12-volt battery.
The solar cell module does not provide power to
the Li-ion battery.
 

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Digging up an old thread here but wanted to avoid repeating whats already been said. I'm off on holiday soon which mean a 25 mile trip to heathrow, was debating whether to take a taxi or take the 2011 leaf and park it there for two weeks until i'm back, the costs work out about the same.

A 50 mile round trip seems just about doable assuming no battery drain in the meantime. But i've heard the battery will drain as some power is used to keep it at 'optimal temperature' rather than the 0 degrees it currently is. Is that true? If so how much drain can i expect in two weeks?
 
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