Another Way to Enforce 80% SoC Charging

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SageBrush

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I've been slowing learning about home automation stuff and think that it is pretty straightforward to use it for this task

Toys needed:
1 CT (current transducer sensor)
1 Smart breaker
1 Hub

Overview
When the LEAF SoC reaches a thresh-hold, the car pulls ever lower currents with increasing SoC to protect the battery. Since the current draw is SoC dependent, measuring the current is similar to reading the battery SoC. Once a car owner decides the threshold current they want to stop charging, it becomes a small matter for the hub to query the CT for its current, and to direct the smart breaker to flip to off when current drops below the assigned level.

That simple, really.
My only small hesitancy here is a system that cuts off the EVSE with a brute switch. I'm sure that is fine for the occasional grid hiccough but I'm not sure it should be a daily routine. A smart EVSE that could be controlled by the Hub would be more elegant.
 
I've always wondered that since Nissan did have that function long ago in the 2013 model, if something like it still exist in the code and can be turned on or off via some Nissan console tools for example as a diagnostic test. At least if something did exist like that, it could lead to something that could be put into LeafSpy. :eek:

At 80% charge though, seems my L2 is still pulling the full current all the way towards +90% if the temperature isn't too cold. Might be a tough project to get it the way you want it to work.
 
knightmb said:
At 80% charge though, seems my L2 is still pulling the full current all the way towards +90% if the temperature isn't too cold.
Noted, thanks.
Stopping at 90% SoC though is still the large share of the benefit of stopping at 80% SoC
 
no rate decrease on my car at 80%....as I said before...

Using the display in the car...if it says 5 hours to 75% use a timer on your phone set to 5 hours then when your alarm goes off go unplug it...or set the car charge timer to come on at 1:00 am and go off at 6:00 am...or whatever time combination works for your schedule and the hours needed to 75%.

Either method works great for me and I do this all the time...the car will charge to 75% plus or minus a few percent either way due to the time estimate.
 
Seems like it would be easier to break the connection for the pilot signal to stop charging "safety" vs. just killing the power to the EVSE. It would take some kind of in-between bridge connector to do it, but could work more towards your goal of doing a safer disconnect once the power level you want is reached.

SageBrush said:
My only small hesitancy here is a system that cuts off the EVSE with a brute switch. I'm sure that is fine for the occasional grid hiccough but I'm not sure it should be a daily routine. A smart EVSE that could be controlled by the Hub would be more elegant.
 
Learjet said:
no rate decrease on my car at 80%....as I said before...

Using the display in the car...if it says 5 hours to 75% use a timer on your phone set to 5 hours then when your alarm goes off go unplug it...or set the car charge timer to come on at 1:00 am and go off at 6:00 am...or whatever time combination works for your schedule and the hours needed to 75%.

Either method works great for me and I do this all the time...the car will charge to 75% plus or minus a few percent either way due to the time estimate.

Some EVSE actually have timers you can set for shut-off built in, so that might be helpful for those that have that type installed.
 
knightmb said:
Seems like it would be easier to break the connection for the pilot signal to stop charging "safety" vs. just killing the power to the EVSE. It would take some kind of in-between bridge connector to do it, but could work more towards your goal of doing a safer disconnect once the power level you want is reached.

SageBrush said:
My only small hesitancy here is a system that cuts off the EVSE with a brute switch. I'm sure that is fine for the occasional grid hiccough but I'm not sure it should be a daily routine. A smart EVSE that could be controlled by the Hub would be more elegant.

That type of solution already exists, see "BatterySaver" heading on Dala's EV repair website:

https://dalasevrepair.fi/#products
 
alozzy said:
That type of solution already exists, see "BatterySaver" heading on Dala's EV repair website:

https://dalasevrepair.fi/#products
You may wish to read the description, Can-bridge required
 
knightmb said:
Some EVSE actually have timers you can set for shut-off built in, so that might be helpful for those that have that type installed.
Yeah ...
I'm not positive about the Grizz-L smart EVSE but since it uses open source protocols for its Wi-Fi control it may be a natural target for this type of automation
 
SageBrush said:
alozzy said:
That type of solution already exists, see "BatterySaver" heading on Dala's EV repair website:

https://dalasevrepair.fi/#products
You may wish to read the description, Can-bridge required

Yes, I realize that - but it works. Nobody mentioned price as a consideration :)
 
SageBrush said:
alozzy said:
That type of solution already exists, see "BatterySaver" heading on Dala's EV repair website:
https://dalasevrepair.fi/#products
You may wish to read the description, Can-bridge required
Getting ready to test this out: I'm installing Dala's CAN-bridge for a battery swap this weekend!
 
I wrote some Smarthings code to run a dust collection system based on load sensed from a Zwave smart switch. You could 100% do the same, although the Aeon plug I based off is 15amp 120V max.

https://community.smartthings.com/t/app-to-manage-shop-garage-dust-collector-vacuum-system/46753
 
Stanton said:
alozzy said:
That type of solution already exists, see "BatterySaver" heading on Dala's EV repair website:
https://dalasevrepair.fi/#products
Getting ready to test this out: I'm installing Dala's CAN-bridge for a battery swap this weekend!
DougWantsALeaf said:
Awesome, please post some pics of the process.
Dala's BatterySaver solution works so well that I'm considering dropping timer-based charging and going with a permanent 80% or 90% charging solution (just plug it in and fuggedaboutit). Now that I have a bigger (40 kWh) battery pack, I don't have to charge as often...so letting the pack "cool down" before charging is not as big of an issue. In addition, it takes so long to charge (I have the original 3.3 kW charger) that I drive soon after it's finished. Kind of an unexpected benefit of my upgrade(s).
 
Thanks. Some of these solutions seem complex. I just bought a 2018 PLUS, and was wondering how to limit charging. I'm retired, and we usually drive the M3. (easy to set up start time and charging limit. For me, in town, it's 60%, ~165mi?)
I doubt if I'll be driving it much, and will probably charge it 2-3 times a month, at most? I start charging at 11p, and will figure out when it needs to shut off.
 
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