Info on the Lead Acid Battery of the Nissan Leaf? (To be used with an Inverter for appliance use)

[NissanLeafCamper]

connected the negative to the body of the top part of the motor.

Hey Brock good to hear from you. I read through that thread but did not notice you were a 2013 owner. Model S to boot! From what you told it sounds like the dc to dc converter on the 2013 leaf provides the same about of power as the 2011 and 2012 dc to dc. That is good news. Were you also able to check voltage with the wipers running by any chance to see if it went up to 14.5v? You did not mention it, but I wonder if you had done any additional testing after that.

For the negative cable you mention "The body of the top part of the motor" Is this the same spot where the negative wire from the battery is hooked up to? Is it okay to clamp down the inverter's negative on the same spot as the lead acid battery's negative wire is? Would it cause problem if they are both hooked up together?

You can see the negative wire connected here at the top part of the picture. There is also another point that holds the wire in place. It does not seem to be a connection point but rather a holding point to hold the wire up. Would this be a good spot to connect the inverter? What is the purpose of holding the wire up like that? Just so it does not pull down where the wire is connected?

I also noticed that the negative wire of the battery is grounded? at two places? first it loops to the driver side and attaches to the metal frame of the car's body.

Then it loops around to the passenger side and connects to the top part of the motor (First pic I posted). Why two connection points for the negative wire of the lead acid battery? Is it just insurance against something?

Also, why the danger of the connections of the inverter to get hot? Is it because the surface area of the connection is small? Is it better to have a bigger surface area connected? Huge copper wires are best? What is the risk of the connections getting too hot? Melting? fire? Should I keep a fire extinguisher close by? I would likely run the induction cooker for about 10 minutes or 15. Depends on what i'd cook. Eggs are super fast though.... Frying meat might be a little bit at 10 I think.

 

[BrockWI]

I haven't tried the wiper motor trick, I think the 13.1v it sit's at is fine for powering the external inverter. Yes I connected the negative lead right where the aux battery's lead connects. And yes I would assume that second connection point or wire holder is just to keep that cable where it should be and not moving around much.

I am not sure why the negative lead connects at two points, my guess is to make sure the car has a good ground between the motor and chassis.

When I was checking things for heating up mostly I was concerned about the positive and negative clamps to the inverter itself, if I used this regularly I would hardwired it. Yes if there is a weak connection it could heat up and potentially melt, as well as drastically reduce the capacity of power the off board inverter can handle. Fire extinguishers are always good to have around I have two in our garage, one at the entrance to the house and at the opposite side at the person door leading out the back.

I did run the setup with the 2000w inverter powering a 13 amp @ 54 v charger (approx 750w) when we had an extended outage last year. It ran for about 3 hours, and the leaf had no problem with the load and nothing got warm.

 

[LeftieBiker]

A voltmeter on the battery might show a slight jump or drop in voltage when the wipers are turned on (or a drop followed by a recovery) or it might not. Not that is worth a try.

Actually, the voltage RISES from 13.1V to 14.5V when the wipers are turned on.

That's the way it ought to behave. I just didn't trust Nissan to get it right.

 

[NissanLeafCamper]

I did run the setup with the 2000w inverter powering a 13 amp @ 54 v charger (approx 750w) when we had an extended outage last year. It ran for about 3 hours, and the leaf had no problem with the load and nothing got warm.

Hi Brock!

It sounds like the dc to dc has the same out put as the one in the 2011 / 2012. Since the dc to dc can only give out like 1.7k watts we are restricted to only that much power? Meaning, bigger inverter won't help because output is only 1.7k?

http://www.solar-wind.co.uk/cable-sizing-DC-cables.html

I was given that link to find out what size of wires I should use for the inverter. I entered 1% acceptable loss,12 volt system voltage, 166.66 amps (I did 2000w/12v), and entered 1 foot (0.3048m) for cable length. Recommended size is 4 awg. Does this sound like a good size cable?

To be honest I don't think 1 foot of length would be enough to run the inverter inside the leaf? I also have no idea how I would run the cables inside the leaf. Would you happen to know what is the best way? In the other thread for black out inverter someone mentioned a firewall.... but I don't know what that is.

I like charging my netbook in the car and it only uses 36w. Do you think using the xantrex is over kill for charging the netbook? How much Watts will the xantrex consume while on? I have a small 150w modified sinewave inverter that I plug in the aux socket to charge my netbook. Obviously I will be charging my laptop more often than when I will actually cook/blend. So if the xantrex uses more watts just for being on... it makes me wonder if I should stick with the modified wave inverter for that purpose.

What do you suggest Brock? Thanks for your information BTW it has been really helpful

 

[BrockWI]

I would suggest a larger inverter because a larger inverter can handle surges better than a smaller one. Say your trying to start a full sized fridge, a 1000w unit might fault out on the motor start but a 2000w unit will likely start it. As far as the 1700w from the Leaf's converter, remember again the Leaf's small 12v battery will act as a buffer allowing you to pull more than that 1700w for a brief time. So say a motor needs 3000w to start and 400w to run, the 2000w inverter will handle that start up surge and the battery will temporarily add it's capacity to that starting surge of power.

The two biggest factors in most folks not being satisfied with an inverters performance is using to small wire input side wires. Even #4 at 4 feet, trying to start a 400a surge of a motor start will drop the voltage to much and the inverter will fault out, it's not that the inverter can't handle the load, it just doesn't have the supplied power to do so. Secondly is an undersized battery feeding the inverter. It's the same problem, the voltage sags under large starting current and again the inverter see's this as a fault condition and shuts off. In this case the Leaf's small starter battery is only acting as a buffer, really relying on the dc-dc converter in the Leaf and that being supplied via the traction pack.

As to the size of wire your using, it totally depends on the loads on the up stream side. If you have any motor starts, just quadruple the wire size from that calculation on Wind & Sun. If your running restive loads or similar you can size it to what you should. Worst case you start with #2 and see you have a problem, you can always up size that input wire.

I leave my inverter right next to the battery so I never looked at how I could get the heavy wire in to the cabin.

Don't forget to fuse that wire, shorting out a #2 wire will ruin your day with no fuse in place, bad, bad things can happen.

For smaller loads, under say 200w I would just use a smaller inverter, the 2000w xantrex uses about 400mA sitting idle on, it's not a small inverter, my 400w inverter uses about 50mA sitting idle, the right tool for the right job...

 

[NissanLeafCamper]

Thanks Brock.

Do you think the blender at 375w will require a starting surge higher than 1800 watts? I will only use the inverter with the 1800 watt induction cooker and the 375 blender, but I wonder if in the future I will use it with something that has a bigger starting surge? What do you think is the highest starting surge the xantrex2000 can handle? 3,000 watts is already a lot... do you think it could go up as high as 4,000watts for a starting surge? I am wondering if I should look into something bigger than the xantrex2000. I don't think I will use it with a bigger appliance in the near future. In the longer them though... I am not sure. Would you be able to recommend something bigger just to see price difference?

Then to be on the safe side I should order 2 AWG or better yet stick with 1 AWG? Are there any negatives toward using too big of a wire? I'm going to keep the installation under the hood. I think this would make it much easier and less costly with the wire; plus the extra money can go toward getting thicker cables. When I cook or blend it should be outside the leaf. It'd be awkward doing it inside....

Okay I will stick with my 150 modified sinwave inverter to charge my 36w netbook. Thank you for answering that question I had herd that the bigger the inverter it is the more it drains when on, but I actually did not know for sure.

Do you remove the inverter when not in use? Or do you always keep it under the hood of your car? If you do... would it be possible to see a picture of where you have it mounted? If you leave it under the hood... does it not get dirty? What about getting hot from the nearby engine? or the radiator... i think the leaf has one, albeit I think it is a small one.

In the Xantrex2000 reviews at amazon some people mention installing a breaker. I also see that it is frequently bought with "E2 by Scoshe EWFH Single ANL Fuse Holder". I'm new to all of this, but it seems to be worth getting the Fuse Holder. I think there are also breaker versions of this device? Do you recommend me getting either a fuse holder or a breaker ... box version? I've read that fuses are inexpensive, so if it can save the $300+ then it should be worth it.

One issue mentioned for that holder is that it cannot hold very large wires.... Are you able to recommend any?

Another issue is the DC to DC converter "Folding Back" from too much of a load? Taking that into consideration.... Should I use a fuse to mainly protect the DC to DC current or the xantrex2000 capabilities? I'm not sure at what demand the DC to DC converter "Folds Back" but if it does... won't that put me in the risk of the battery being completely drained?

Do you know if the xantrex has a feature to protect the battery when it gets to low? Auto shut off I think it is called.

 

[BrockWI]

I would think that blender will work on a 1000w inverter fine, the 2000w won’t even notice it. With good sized cable you should be able to run any single item you can plug in to it, including a stock leaf EVSE, yes I have tried it, so I would stick with the sw2000.

Personally I would go with 1 AWG because you plan to use the induction burner. I usually leave my inverter at home, we did take it to a park this summer and used it to run some loads, and everyone thought it was cool It is just in the trunk until I need it.

For you laptop you might look at a 12v supply option and just avoid the inverter, but if you already have a small inverter it will work.

You could go the breaker route, I went the fuse route because it is less expensive and smaller, sort of like a big inline fuse. I got mine from Wind & Sun and matched it to what I have on my solar PV bank since I already had them and know they work well. They handle up to 4/0 passing through. At Amazon look at the Go Power FBL 200 block, they look very close to what I have, they are the same class T fuses.

I am not sure what “folding back” is, so I can’t help with that, hopefully someone will chime in.

Yes the inverter will just shut off if it gets below 10.5v and beeps constantly I believe at 11.5v With the Leaf on you shouldn’t ever see it that low, you just have to watch your main pack to make sure you don’t run it flat. But the car will shut off and then the aux battery would very quickly be drained as well, then you would be really stuck

 

[GerryAZ]

BrockWI has good points on inverters. There is no need to unplug the windshield wiper motor. If you really want the DC-DC converter to provide over 14 volts output while you are using the inverter, just connect the inverter's negative supply directly to the negative terminal of the 12-volt battery. The reason Ingineer recommended against connecting accessory loads to the negative terminal of the battery is because the Hall-Effect sensor on the negative battery lead sees the accessory load as 12-volt battery charging current and keeps the charging voltage high. With my 2011, the charging voltage stayed above 14 volts until the current dropped below about 10 amperes. With my 2015, the charging voltage drops to float voltage of about 13 volts when the current drops below about 5 amperes.

Although I have told you an easy way to keep the voltage high, I recommend that you connect the inverter negative supply to chassis ground and let the 12-volt battery system run at normal float voltage (about 13 volts). The 12-volt battery will be overcharged if the voltage stays at 14 or higher for extended time. Overcharging a vented lead acid battery causes excessive gassing in the cells and loss of electrolyte. This means you would need to add distilled water to the battery more frequently and you might see corrosion on metal in the vicinity of the battery. Overcharging a sealed lead acid battery will shorten its life and could cause catastrophic failure if internal pressure from gassing gets too high.

Gerry