Page 3 of 4

### Re: How Do You limit charging to 80%???

Posted: Fri Aug 04, 2017 6:59 pm
If you leave for work at a consistent time, you could set the charger to end charging an hour _after_ you actually expect to leave. Then, when you unplug the car and drive off, it will be 1 hour short of full charge. (That said, if you're driving off right away, there's little harm in charging to 100%).

If you use the trickle charger, you could plug it into a timed outlet (which is rated for 15 amps), and program the outlet to power off 1 hour earlier than when the car is programmed to finish charging.

If you DIY home automation, there are relays which can disconnect 50A, driven by a Raspberry Pi, or similar. You could also connect at ammeter to a Pi and try to detect when the current draw starts to decline. But obviously, that's for pros.

### Re: How Do You limit charging to 80%???

Posted: Fri Aug 04, 2017 8:48 pm
If you leave for work at a consistent time, you could set the charger to end charging an hour _after_ you actually expect to leave. Then, when you unplug the car and drive off, it will be 1 hour short of full charge.

The charge estimate on the dash is generally pessimistic, and the timer seems to use the same algorithm. Setting the timer for one hour after actual departure time might yield a charge surprisingly close to 100%, although as noted this isn't a problem if the car is used shortly thereafter.

### Re: How Do You limit charging to 80%???

Posted: Tue Jul 10, 2018 12:33 am
I built a timer box for \$60 of materials. It works great. We just set the timer based on what's needed to get to 80 percent. Much easier and less hassle than working with the Connect App or the onboard timer for a car that isn't driven every day. We plug it in one hour before leaving to get the last 20 percent on the day it will be driven.

### Re: How Do You limit charging to 80%???

Posted: Mon Aug 27, 2018 10:16 am
I did something similar to KraigShultz: in-between the EVSE and car, add a J-box in which you cut the EVSE signal wire(*), and connect the ends to the two terminals on an unpowered 12-hour timer switch (I used a Westek TMSW12HW). In my case, my EVSE was charging at 12A, or about 10% SOC per hour, so if the Leaf SOC was at 40%, I'd twist the timer knob to "4 hours" and plug-in, and hit the "charge now" button. Or, if I wanted a 100% charge, I just twist to "12 hours" and let the car's charge timer handle when to begin charging.

You could also interrupt one of the 240v legs, but I had read on another post on MNL that there were some negative aspects (I forget... maybe the car beeped at 3am when the power was cut off; or it threw a DTC code sometimes, or something like that). Obviously, you're also limited by the amp rating of the timer switch (10a in my case). By interrupting the signal wire, you are doing exactly the same thing as if you had grasped the J1772 connector and depressed the disconnect thumbswitch... and then stood there until morning.

(*)it's the thin wire

### Re: How Do You limit charging to 80%???

Posted: Mon Aug 27, 2018 4:32 pm
There may be an easier option, see this thread:

viewtopic.php?f=44&t=26040&start=10

Sounds like @mux has it on his ToDo list, hopefully he'll see this thread and comment on any progress he's made. Using his "man in the middle" CAN-BUS device does seem like the best approach...

### Re: How Do You limit charging to 80%???

Posted: Sat Sep 08, 2018 7:16 pm
I wouldn't bother. There's a problem with charging to 80%, actually two problems. One, 12 volt battery charges after Li-Ion battery is full, so if you don't charge to 100%+ then the 12 volt battery is working exclusively off of the Li-Ion, and the 12 volt runs accessories (AC/Heat etc.). Two, all rechargeable batteries have flexibility, or memory. So if you charge to 80% all the time, soon it may not charge to 100%. I've found that my Leaf (2015 S purchased used @ 36k mi.) shows higher range at 100% charge if we get as much as we can out of each charge. I've run it until the low battery warning comes on twice (@ 18 miles until exhaustion) and both times the next morning showed the highest full charge range of 98 miles. Drive it. Charge it. Repeat. Vary how much you run the battery down, occasionally running it down as far as you can while still making it home or to a charging station. It's made to be charged up and driven. Don't over think it. It doesn't care. Full charge range will also vary with weather and the previous day's driving conditions and performance.

### Re: How Do You limit charging to 80%???

Posted: Sat Sep 08, 2018 7:24 pm
Rolinpin6061 wrote: One, 12 volt battery charges after Li-Ion battery is full, so if you don't charge to 100%+ then the 12 volt battery is working exclusively off of the Li-Ion, and the 12 volt runs accessories (AC/Heat etc.).

Nope on 1st part. Nope on the AC and heat.
Rolinpin6061 wrote:Two, all rechargeable batteries have flexibility, or memory. So if you charge to 80% all the time, soon it may not charge to 100%.

Nope on li-ion batteries. This was true of ni-cad batteries.
Rolinpin6061 wrote:Full charge range will also vary with weather and the previous day's driving conditions and performance.

You're talking about the variance in the stupid guess-o-meter due to recent driving history.

### Re: How Do You limit charging to 80%???

Posted: Sat Sep 08, 2018 7:56 pm
Just quoting the Owner's manual. Section CH-30. When plugged to charger, 12 volt battery charges after Li-Ion is full, if necessary. Take it up with Nissan, not me.

And yes, accessories most certainly do run off of 12 volt, Section EV-2. Again, owner's manual. Li-Ion recharges 12 volt, Section EV-5.

Why does everyone think they know better than the manufacturer? If you did, wouldn't you be an engineer at Nissan or Tesla?

Have a nice day.

### Re: How Do You limit charging to 80%???

Posted: Sat Sep 08, 2018 8:12 pm
Rolinpin6061 wrote:Just quoting the Owner's manual. Section CH-30. When plugged to charger, 12 volt battery charges after Li-Ion is full, if necessary. Take it up with Nissan, not me.

The 12-volt is also "charged"/"maintained" by the DC to DC converter when the car is in READY mode (green car with arrows). If you activate the wipers, the 12 volt bus voltage will jump to about 14 volts and stay elevated for awhile, before dropping back down to its too low maintenance voltage (~12.88 volts, IIRC). You can see this with Leaf Spy. It's been discussed here many times.

Page CH-30 of the '15 manual definitely does not say what you claim. Also, page EV-5 says
CHARGING THE 12-VOLT BATTERY
The 12-volt battery is charged automatically using
electricity stored in the Li-ion battery.
When the 12-volt battery is being charged, the
charge status indicator light on the instrument
panel flashes (except when charging the Li-ion
battery or the power switch is in the READY to
drive position). See “Charge status indicator
lights” in the “Charge” section.
While vehicle is driven
The Li-ion battery charges the 12-volt battery as
necessary when the power switch is in the
READY to drive position or ON position.
...
While the vehicle is not in use
When the EV (Electric Vehicle) system is off for
an extended time, the 12-volt battery may be
automatically charged for a short period of time
on a regular basis.

In fact, if you leave a car plugged into an EVSE for an extended period of time (e.g. weeks), you will return to a dead 12 volt battery. For some stupid reason, the car is inhibited from doing the above (periodically charging the 12 volt from the li-ion battery) when plugged in. This has been discussed over and over here.

On older manuals, like for the '11, they actually talked about a 5 day interval for light #3 (li-ion battery charging the 12 volt). The li-ion battery doesn't need to be full for this to happen.
While the vehicle is not in use
When the EV (Electric Vehicle) system is off, the
12-volt battery charges automatically for 5
minutes every 5 days.
The charge timing resets to 5 days without
charging the 12-volt battery if:
. The vehicle is placed in the READY to drive
position for more than 5 minutes.
. The Li-ion battery is charged for more than 5
minutes.
When charging the 12-volt battery, the charge
status indicator light, on the instrument panel
illuminate. See “Charging status indicator lights”
in the “CH. Charging” section.

cwerdna wrote:Nope on the AC and heat.

Rolinpin6061 wrote:And yes, accessories most certainly do run off of 12 volt, Section EV-2.

It says
The 12-volt battery provides power to the vehicle
systems and features such as the audio system,
windshield wipers.

Yes, it supplies those but so does the DC to DC converter when in READY mode. You claimed
Rolinpin6061 wrote:the 12 volt runs accessories (AC/Heat etc.).

It does NOT run AC NOR HEAT other the fan. The manual doesn't say it does. AC compressor and heater are run off the high voltage bus. The wires from the 12 volt bus would need to be VERY thick to meet the power requirements of the AC compressor and PTC heater.

If you look in the service manual (e.g. HA and HAC sections for HVAC), you will see high voltage warnings over and over in them.

If you look at pics of Leaf AC compressors (e.g. at https://www.ebay.com/itm/11-15-NISSAN-L ... 2067304036), you'll notice the orange cable and connector, denoting high voltage. You can also see the that at the bottom of https://www.marklines.com/en/report_all/rep1104_201209 for the compressor and PTC heater (that's the one from the '11 and '12 Leaf).

Also reference page FRG-9 of the 2015 Leaf First Responder's Guide at http://www.boronextrication.com/emergen ... rg-hybrid/. You'll notice that Electric air conditioner compressor and cabin heater have a white number in a black background, denoting high voltage.

Stop misinterpreting or adding words what the owner's manual says.

### Re: How Do You limit charging to 80%???

Posted: Sat Sep 08, 2018 9:59 pm
With 2 posts, both similarly pugnacious, I think Rollinpin may be a troll.