How Do I Charge To 95%

[gmcjetpilot]

If you have LeafSpy (LSpy), this is pretty easy to figure out:

1. Read from LSpy your battery capacity at 100%
2. Let us know your EVSE volt and amp specs

Then we can tell you the battery % charging increase per time.

As an example,
My EVSE charges up the car 1% every two minutes (an L2 240 volt, 30 Amp device that sends ~ 6 kWh per hour to the battery)
If I return home at a SoC of 30% and want to leave the car at 80%, I set the timer to charge 100 minutes.

---
If you do not like arithmetic, then do this:
Note the starting and ending SoC after an hour charge.
The difference is the percent increase per hour.
NOTE that different EVSEs may have different charging rates, so the results may not be transferable.

Thanks I don't have LeafSpy (LSpy) yet. I guess it is just a Bluetooth on OBSII Dongle and a free App?

My Clipper Creek Charger is 20 AMP or 220 x 20 = 4.4 KWh (estimate). I have the 6.6 KWh charger.

I can see from my two charges charge time (typical will be 3:30 hours to 2: hours (or less).

[SageBrush]

The 20 Amp Clipper Creek will run at 16 Amp continuous for safety reasons, so your throughput is about
16A*240V = 3840 watt. About 12% is lost to heat, so about 3840*0.88 = 3379 watts into the battery.

The missing information for now in your case is that you do not know the battery capacity so it is simpler to just learn through experiment how many percent the battery takes up in an hour. Since your end goal is to reach a specific percent anyway, you might as well leave everything in percent units.

[DaveinOlyWA]

I know my 2015 has newer battery design. Nissan says it's OK to charge to 100% every time. However some experts still recommend you don't, limit charge to 95% (and they give technical facts to back it up). The advice to not leave battery at 100% for extended time is still valid I assume.

Does anybody have any clever idea on how to do charge to 95%. I know you can use the charge timer to limit the amount of time you charge, but calculating the exact time to shut it off is kind of tricky. I've tried it a couple times to reduce charging time. Apparently not enough, it ends up at 100% anyway. Is there some way to set shut off at 95%? Is there a time to charge chart based on temperature and starting charge to get to 95%?

You can do this but it will take some work on your part due to differences in home EVSEs.


First;

*check SOC

*Check estimated charge time for your EVSE (you will have both slow and fast L2 times listed)

*set end timer to 3 hours AFTER you plan to be up the next day.

*next day (or whenever) get up check SOC.

record all this data over a few days.

Analyze data. You will likely find that it becomes easy to hit your target SOC within a 5-10% delta. (charge times jump in 15 min increments at times)

what you need to look for;

Making sure you check your charge before it gets to balancing stage. This is why I recommend 3 hours. I would be specific but cannot because your EVSE is different than mine.

Yes, this requires setting end time for charging EVERY NIGHT.

Finally; why 95%. The general consensus is 90% based on Bolt, Tesla, etc.

FYI; your best bet is running your car at lowest SOC that covers your needs. This grows in importance with the Mercury. When cold (if it gets cold for you) the issue is pretty small and range is reduced in Winter so charging to full is a not the "best" option but also not significantly bad either. Its better to play it safe than be stranded in life threatening weather

[SageBrush]

I know my 2015 has newer battery design. Nissan says it's OK to charge to 100% every time. However some experts still recommend you don't, limit charge to 95% (and they give technical facts to back it up). The advice to not leave battery at 100% for extended time is still valid I assume.

Does anybody have any clever idea on how to do charge to 95%. I know you can use the charge timer to limit the amount of time you charge, but calculating the exact time to shut it off is kind of tricky. I've tried it a couple times to reduce charging time. Apparently not enough, it ends up at 100% anyway. Is there some way to set shut off at 95%? Is there a time to charge chart based on temperature and starting charge to get to 95%?

You can do this but it will take some work on your part due to differences in home EVSEs.


First;

You win the Rube Goldberg medal for complicating something trivial.

Step 1a: Charge for about an hour and note the SoC change per minute

Step 1: Arrive home and decide how much you want to charge in percent
Step 2: Divide Step #1a into Step #2. You now know minutes to charge
Step 3: Set start charging time (Step #2) minutes before the end charging time

Example, using my car and my EVSE:
It takes 2 minutes to gain one percent

I arrive home with a SoC of 25% and want to charge to 80%
I set the start timer 130 minutes before the end charge time.

---
That is for the OCD amongst us.
Everybody else can just set the start timer to match their typical drive routine and only calculate the unusual days.

[gmcjetpilot]

The 20 Amp Clipper Creek will run at 16 Amp continuous for safety reasons, so your throughput is about
16A*240V = 3840 watt. About 12% is lost to heat, so about 3840*0.88 = 3379 watts into the battery.

The missing information for now in your case is that you do not know the battery capacity so it is simpler to just learn through experiment how many percent the battery takes up in an hour. Since your end goal is to reach a specific percent anyway, you might as well leave everything in percent units.

My charger is a LCS 25 (not a LCS 20), and it runs at 20 amps continuously (needs a 25 amp breaker). The .88 efficiency factor is a good tip. Also my line voltage is a little under 240 volts. What I see is there is little difference in LEVEL 2 charging from 16 Amp to 30 Amp... The quantum jump is going from LEVEL 1 to LEVEL 2.

[gmcjetpilot]

You win the Rube Goldberg medal for complicating something trivial.
Step 1a: Charge for about an hour and note the SoC change per minute
Step 1: Arrive home and decide how much you want to charge in percent
Step 2: Divide Step #1a into Step #2. You now know minutes to charge
Step 3: Set start charging time (Step #2) minutes before the end charging time
---
That is for the OCD amongst us.
Everybody else can just set the start timer to match their typical drive routine and only calculate the unusual days.

There are variations or differences in rate of charge, due to temperature and other factors, including starting SoC. The charge rate is not linear. Yes your rule of thumb is a good ball park, and for your typical charge can come up with a time. From my two monitored charges my typical charge will be about 2-3 hours. My charge rate varied from 3.9% to 4.75% every 10 minutes.

[gmcjetpilot]

Finally; why 95%. The general consensus is 90% based on Bolt, Tesla, etc.

FYI; your best bet is running your car at lowest SOC that covers your needs. This grows in importance with the Mercury. When cold (if it gets cold for you) the issue is pretty small and range is reduced in Winter so charging to full is a not the "best" option but also not significantly bad either. Its better to play it safe than be stranded in life threatening weather

[/quote]

I got the 95% from the YouTube Video
Title: Fast Five: How To Keep Your Electric Car Battery Healthy
Channel: Transport Evolved
Date Aug 30, 2017
https://www.youtube.com/watch?v=AoYmSLBQYDc

[jlv]

Ignore the "experts" who created that video.

Just charge and drive the car as needed. Don't worry about 95%.

[LeftieBiker]

Ignore the "experts" who created that video.

Just charge and drive the car as needed. Don't worry about 95%.

You might also want to ignore this expert. Limiting charge in hot weather is reasonable and prudent.

[jlv]

You might also want to ignore this expert. Limiting charge in hot weather is reasonable and prudent.

I'm no expect, nor do I pretend to be one on the Internet.

I agree that limiting charging in hot weather is reasonable and prudent. That video makes overbroad statements that it attempts to apply to all EV batteries equally. That's not useful.