how much charge does it cost to park for 3 weeks?

[caSteve]

I'm going out of town for a about three weeks. Was planning to leave my leaf parked near the airport for the whole time. It will have about 70% charge when I park it. I believe that the drive battery would lose almost no charge over that time, except that if I understand correctly, it'll act as a battery maintainer for the 12V battery. Anyone have an idea of how much that'll cost me in terms of the charge on the drive battery?

 

[although]

I wouldn't expect any significant loss in the drive battery from maintaining the 12v battery. I seem to recall that the manual warns against leaving the car for long periods in a fully discharged or a fully charged state. But that has more to do with the overall health of the battery than any loss of charge.

The load on the 12v battery when the car is off is likely measured in milli-amps. The drive battery capacity is measured in kilo-watt hours. I'm going to go out on a limb here and say that this will be a non issue.

Mike

 

[GerryAZ]

Make sure you unplug anything connected to the OBDII port and turn the car off when you park it. You will loose almost no charge from the traction battery. You may see 1 or 2 percent difference in SOC due to temperature change and 12-volt battery charging. I have left both 2011 and 2015 Leafs sitting at the office or airport for extended trips (up to and including 3 weeks) without incident. The only time I had a problem was when I forgot to unplug the ELM unit from the OBDII port and left the Android device running Leaf Spy Pro on the passenger seat. Leaf Spy was probably requesting data until the battery in the Android device died. This likely discharged the 12-volt battery and I came back to a non-responsive Leaf after 6 days out of town.

Gerry

 

[epirali]

Make sure you unplug anything connected to the OBDII port and turn the car off when you park it. You will loose almost no charge from the traction battery. You may see 1 or 2 percent difference in SOC due to temperature change and 12-volt battery charging. I have left both 2011 and 2015 Leafs sitting at the office or airport for extended trips (up to and including 3 weeks) without incident. The only time I had a problem was when I forgot to unplug the ELM unit from the OBDII port and left the Android device running Leaf Spy Pro on the passenger seat. Leaf Spy was probably requesting data until the battery in the Android device died. This likely discharged the 12-volt battery and I came back to a non-responsive Leaf after 6 days out of town.

Gerry

Just want to second that. I has no loss when I left the Leaf for 5 weeks. I suggest leaving it at 40-50% charge if you can.

 

[LeftieBiker]

Top off the 12 volt battery with an external charger before you park it, because the Leaf does a mediocre job (at best) of maintaining its accessory battery's charge. Some Leafs have been found to have 'phantom drains' that will kill the accessory battery if left alone, while others seem to be just fine. If you have any doubts (and really, even if you have none), check the 12 volt battery's voltage after it sits a while. If it's close to 13 volts it's fine. If it's closer to 12.5 volts it's undercharged.

 

[GerryAZ]

With over 50,000 miles driven in the 2011 and over 10,000 miles so far on the 2015, I have NEVER charged the 12-volt battery with an external charger and had no issues except the one caused by leaving Leaf Spy running as noted above. When I came back to the office and found the 2011 non-responsive, I jump-started it from my office vehicle using some No. 14 AWG test leads. The 2-1/2 year old original Nissan battery was recharged from the DC-DC converter by the time I got home that night. Unfortunately, being deeply discharged took its toll and that old battery died about a month later (2-1/2 years is actually very good life for a conventional lead acid car battery in Phoenix). I replaced it with an AGM deep cycle battery (Optima Yellow Top) which was still going strong when the car met it's demise. I wanted to remove it from the car and keep it for a spare, but the insurance company's storage yard would not allow it.

Gerry

 

[caSteve]

Thanks all -- this was a great help.

 

[epirali]

Top off the 12 volt battery with an external charger before you park it, because the Leaf does a mediocre job (at best) of maintaining its accessory battery's charge. Some Leafs have been found to have 'phantom drains' that will kill the accessory battery if left alone, while others seem to be just fine. If you have any doubts (and really, even if you have none), check the 12 volt battery's voltage after it sits a while. If it's close to 13 volts it's fine. If it's closer to 12.5 volts it's undercharged.

Very good point. I always used to do this before parking for a while. It doesn't hurt.

 

[caSteve]

Just a followup. This turned out exactly as people predicted. I topped up the 12V with a maintainer the night before parking outdoors in warm/hot/sunny weather for three weeks. There was no noticeable loss in charge on the drive battery after three weeks. I am now plenty confident to do this again, with or without the use of the maintainer the night before. Thanks for the advice all!