Using D batteries to kick-start the Leaf

[johnrhansen]

Just curious. Why D batteries?

A (very) small 12v SLA battery can be had for ~$10. While it certainly won't jump an ICE car, it's more than enough power for the Leaf's electronics. At 2.1 lbs, you have a single battery you can leave disconnected in the glove compartment, trunk space, or probably even fashion a bucket/case for it parallel to the main 12V (my battery has ~1" extra room on the sides)

Alkaline batteries last forever if they are not used, lead acid batteries on the other hand, will self discharge fast enough so that no voltage will be available if you need it. How about a 12 volt lantern battery?

http://www.apexbattery.com/12v-4200mah-hvy-lantern.html?utm_source=googlepepla&utm_medium=adwords&id=18283950120&gclid=CjgKEAjwuMmdBRDljdfi2_qQpxkSJADDCRwsY21IfV3usjzkgdUEAvTS6D7AIrc_MeqHExLr0uvgVfD_BwE" onclick="window.open(this.href);return false;

 

[kikngas]

I don't get why you can't just put the jumper right on the battery isn't that where the voltage is all the time and where all the current flows from when you first turn the car on?

You never connect jumper cables to the negative terminal. The reason is the same, regardless of what you are jumping. As batteries charge, they can release hydrogen. Think Hindenburg. And so the whole point is not a current level issue, it is a spark issue. Especially when you disconnect the jumpers, that small spark could possibly cause problems. So, you always want that negative terminal to be the last connection, you want it to be away from the battery, and you want the lead going to the battery with the power to be the last lead connected (i.e. connect positive leads, then the negative to frame of dead battery vehicle, then negative to frame of live battery). To disconnect, you reverse the process.

There are certainly scores of people that will tell you that they've jumpered directly to both battery terminals 100s of times and never had any problem. I'm not disputing that. I'm just sayin' that the method described above is safer. It's how you should jump an ICE as well.

Think spark, think Hindenburg, and you can remember the sequence. The dead battery is the one charging and most likely to have hydrogen near the battery. That's why the last connection on, and first removed is on the other end of the cables.

 

[foolios]

I'd like to see some more input on this matter of connecting batteries for jumping.

I was told "Red of the Dead".
So start with positive of the dead battery then to + of the good (Positives), then from that same good batteries negative to the frame of the dead car(Negatives).

So it would work just as well if I didn't hook up the neg to the good battery as well? I can use the frame of both vehicles for jumping purposes?

 

[dgpcolorado]

I'd like to see some more input on this matter of connecting batteries for jumping.

I was told "Red of the Dead".
So start with positive of the dead battery then to + of the good (Positives), then from that same good batteries negative to the frame of the dead car(Negatives).

So it would work just as well if I didn't hook up the neg to the good battery as well? I can use the frame of both vehicles for jumping purposes?

Yes, the negative connection can be the frames of the vehicles on both ends of the connection.

You've had questions about jumping answered before. Anyway, the subject of using a LEAF to jump another vehicle has been beaten to death in other threads. The procedure from our resident expert:
Jumping another vehicle

Since this thread is about jumping a LEAF with a dead battery, the connection sequence should be reversed (and the dead LEAF won't be in READY mode until the connections are made and the start button pushed).

And, since the subject always comes up, the reason the negative connection on the LEAF should be made away from the negative terminal — in addition to the risk of a hydrogen explosion — is because there is a current sensor on the post. Again, from Phil:
current sensor