Posts: 1
Joined: Thu Jan 07, 2021 12:12 am
Delivery Date: 07 Jan 2021
Leaf Number: 400325

60% loss with basic V2H setup (3Kw 12v Inverter)

Thu Jan 07, 2021 12:36 am

Dear Leaf community,
I've been experimenting with powering a house from a 2013 Leaf via a $100 true sine wave inverter ( ... 4915742804) and cannot find a reason for over 60% loss of the power on the way.

The Leaf capacity monitor shows 6 bars and LeafSpy indicates the SOH of around 48%.

When I charge the Leaf to 100% and plug in an electric heater into the 12v to 120v inverter, it takes about 5 hours to drain the main battery to around 20%.

So, ideally, it should be receiving at least 8KWh output. However, the wattmeter shows only around 2 KWh used by the heater. To simulate an emergency, I use a 100ft extension cord between the inverter and the heater, but it shouldn't have more than 60W loss (the inverter indicates 115v output and the wattmeter at the end shows 106v input).

I understand that having the car on will cause some drain. Also, the 12v inverter is probably only about 80% efficient, but that should give me at least 6-7 KWh, not 2. All the accessories in the Leaf are off.

Any ideas what else might be causing such a loss and how to track down a culprit? I'd love to hear your stories if anyone else tried something similar.

Thank you!

Posts: 368
Joined: Mon Jun 05, 2017 10:21 pm
Delivery Date: 06 Jun 2017

Re: 60% loss with basic V2H setup (3Kw 12v Inverter)

Thu Jan 07, 2021 7:12 am

That sounds about right based upon your limited measurement data. Was it about a 400W heater that you were using as the load?

You would need to monitor the voltage and current out of the pack and also in and out of the DCDC and in/out the inverter to see the power split and losses for keeping the car ON and for running the inverter.

Posts: 6
Joined: Mon Jul 06, 2020 6:31 am
Delivery Date: 06 Jul 2018

Re: 60% loss with basic V2H setup (3Kw 12v Inverter)

Thu Jan 07, 2021 7:59 am

This is why im trying to work on a bidirectional chademo v2h like the leaf was designed for.

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Posts: 6257
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: NM

Re: 60% loss with basic V2H setup (3Kw 12v Inverter)

Thu Jan 07, 2021 10:21 am

Some thoughts (may be useful, or way off) ..

Your 12v starts out with a capacity of perhaps 30 Ahr and then it acts as a conduit for your 12v converter. That converter is Amp limited.

So I'm not surprised that the total energy coming out of your inverter is low, but I don't understand where the traction battery energy went.
2013 LEAF 'S' Model with QC & rear-view camera
Bought Jan 2017 from N. California
Two years in Colorado, now in NM
03/18: 58 Ahr, 28k miles
11/18: 56.16 Ahr, 30k miles
09/20: 54.3 Ahr; 38k miles
2018 Tesla Model 3 LR, Delivered 6/2018

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