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I have a 2021Prime SE and am simply using the stock charger plugged into my standard, 120V 12A garage outlet, and I have a few questions:
1) After the battery finishes charging, does it still drain my household electricity at all?
2) Is a "full battery" truly 100% and should be avoided, or is it actually ok to leave it plugged in for 12-14 hours at a time?
3) Is it good/bad/ugly for the battery & car in general if I charge it full, run the kids to school (5 miles), plug it back in, run errands (20 miles), plug it back in, run to my parents' house (35 miles), etc., etc., day in and day out?
Thank You!
 

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I have a 2021Prime SE and am simply using the stock charger plugged into my standard, 120V 12A garage outlet, and I have a few questions:
1) After the battery finishes charging, does it still drain my household electricity at all?
2) Is a "full battery" truly 100% and should be avoided, or is it actually ok to leave it plugged in for 12-14 hours at a time?
3) Is it good/bad/ugly for the battery & car in general if I charge it full, run the kids to school (5 miles), plug it back in, run errands (20 miles), plug it back in, run to my parents' house (35 miles), etc., etc., day in and day out?
Thank You!
1, I don't believe it continues to draw once charging stops. 2. The car only accepts a charge up to 80%. 3. It doesn't matter.
 

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2021 Prime XSE, former Prime SE [sold]
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1, I don't believe it continues to draw once charging stops. 2. The car only accepts a charge up to 80%. 3. It doesn't matter.
Minor correction- the car uses 80% of the battery, which is 10% on each side. Max SOC is ~90% verified by folks with a ScanGuage.

Folks that want to eek every bit of life out of their battery advise not to float the battery at full SOC (which the manual also suggests), and set charge timers to finish charging around expected departure. In OP's scenario I think it's fine for back to back trips like that, but I'd set a departure timer for overnight so that you're not floating it at max charge nearly 24x7.
 

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I have my stock charger connected to a kill a watt.
When its done charging, its done...
Less than 5-10 watts...

When charging, it goes to 1300 Watts...
10.8 Amps..

Previous post is right.
Its an 18.1 KW battery (total)
but only 14.5 is used..
You cant over, or under charge it...

Do what your doing......

They say if the car is in "storage"
Let it sit at 50% rather than 100%

What's storage??
Greater than 2,3 Months if I had to guess.....
 

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2021 RAV4 Prime SE Supersonic Red
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@jeffdrex, welcome to RAV4WORLD.

The 80% trips up a lot of people. The software keeps a buffer at the top end and at the lower end. It's probably best to ignore these buffer areas (since we can't exceed those limits) and just think about the car as being between 0-100% charged. With that in mind, if you plug in the car and let it charge to completion, you will have 100% of the battery capacity. However, if you use the Charge Mode, the car will limit the charge to 80% of the useful capacity. I suspect that this was due to the fact that it's easier to charge a depleted battery to about 80% capacity, which should be enough for most people needing to use the Charge Mode. The software could take it further, but efficiency comes into play, and instead of taking that hit, the designers chose to limit Charge Mode to 80%.

It's better if you don't charge the car to 100% if it's going to be sitting for awhile. My understanding is that it's part of the chemical process and a fully charged battery is less stable. I guess that if you fill it up to 100% and then let the car sit, it would be like filling up an ICE vehicle and then leaving the gas cap off. You might lose some of the charge that you put into it. However, at something less than 100% the battery is better at retaining the charge for a period of time. It also might be detrimental to the health of the battery if it's "stored" at 100%.

You also need to consider how you're going to use the car when you do drive it after charging. If you're going to be using HV mode for something like an extended trip at highway speeds, it's better to have something less than 100% charge so the HV system has a place to put excess energy. The car will run fine, but it might have to throw away the excess energy if there is no place to put it. Lots of people will charge the night before and then start their trip in EV mode. If you want to save the EV mode for the destination, you can manually switch to HV after you've used the EV for a few miles. If you don't care about having any EV capacity left, you can drive in EV mode until the battery gets low and the car automatically changes to HV mode.

There are other threads talking about why the Owner's Manual recommends unplugging the charge plug after it has finished. The thought was that the 12V auxiliary battery continues to provide power to the charging CPU even after charging is complete. While it would be a slow drain, it would be a drain and the HV battery will only charge the 12V battery when the car is in READY mode. Further investigation by dedicated RAV4 owners with ScanGauges found that while the HV battery is being charged, there is a charge also going to the 12V battery. However, it was also found that after charging is completed, the charging of the 12V battery also stops.

You asked about leaving the car plugged in for 12-14 hours, but did you mean after the completion of the charge? I also charge at 120V overnight and don't always go out right away to unplug. However, with the potential drain on the 12V battery, I try to unplug within a few hours of completion.

Regarding topping off after each trip, my understanding is that Li-ion don't mind being topped off. Unlike the old NiCad batteries, there is no issue with the battery forming a memory and a reduction in capacity. I usually take pretty short trips around town and only need to charge every 2-3 days. It's nice to have the ICE as a backup so that I don't have range anxiety, so I just charge when I think I might need to and not worry about starting off with a full charge. If I regularly drove 30-40 miles a day, I would be recharging every day. I guess it comes down to personal preference. Doesn't sound like it would adversely impact the HV battery to be charged regularly, so do whatever works best for you.
 

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2021 Rav4 Prime XSE Pro Audio/Dynamic Nav/Weather Packages Build date: June 2021
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However, with the potential drain on the 12V battery, I try to unplug within a few hours of completion.
I proved to myself this is an internet rumor with no basis in reality, at least when the charger is left connected for up to 15 hours which was the end of my field test. Battery voltage actually went up nicely from where it was at the end of charge completion of the traction battery.
 

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2021 RAV4 Prime SE Supersonic Red
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I proved to myself this is an internet rumor with no basis in reality, at least when the charger is left connected for up to 15 hours which was the end of my field test. Battery voltage actually went up nicely from where it was at the end of charge completion of the traction battery.
I would be interested to to know how you conducted your test, especially how you avoided the Heisenburg Uncertainty Principle.
 

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I would be interested to to know how you conducted your test, especially how you avoided the Heisenburg Uncertainty Principle.
Tested at the 12v battery with a multimeter after traction battery charge complete and the 12v battery was at that time was 12.39v. 16 hours later (with the OEM EVSE still connected) 12v battery voltage actually went up to 12.59v, so it appears the EVSE actually charged the 12v battery during that 16h period, destroying yet another unsubstantiated 'recommendation' (which derived from the manual, w/o any explanation, then propagated by nice folks like yourself ;))
 

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If the 12v battery was charging, shouldn't the apparent voltage be closer to 14v? While charging is occurring, that was the voltage I was seeing measuring the 12v battery. A change from 12.39v to 12.59v could be caused by other conditions like the battery recovering or a change in temperature. I am convinced that the 12v does charge when the HV battery is also charging. What I am unconvinced of though is what happens after the HV charge is completed but the EVSE is kept plugged in.
 

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What I am unconvinced of though is what happens after the HV charge is completed but the EVSE is kept plugged in.
I just told you what happens when the HV charge is completed and the EVSE is kept plugged in. Other details: ambient temp started around 37F and ended around the same, in my garage, on a cold day outside. More important that all of this: it certainly DID NOT discharge in the slightest, and that is what this bogus recommendation claims.
 

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I did a test and agree with Noelin.
I plugged in the rav and the battery voltage with charging. 12.4V
Plugged in with no charging, 12.4V. after 3 hours, after six hours 12.4V, after nine hours, 12.3V, after twelve hours,12.3V.
I then unplugged the car and after twelve hours, voltage was 12.3V.
From this, I would say that if there is a draw after charge is complete that the system maintains the battery at its current level especially when plugged in and not charging. FWIW
When in "ready" mode, the charge to the battery is near 14V, which will drop back to the mid 12s when fully charged.
I used my scan gauge to monitor these numbers.
 

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I have a 2021Prime SE and am simply using the stock charger plugged into my standard, 120V 12A garage outlet, and I have a few questions:
1) After the battery finishes charging, does it still drain my household electricity at all?
2) Is a "full battery" truly 100% and should be avoided, or is it actually ok to leave it plugged in for 12-14 hours at a time?
3) Is it good/bad/ugly for the battery & car in general if I charge it full, run the kids to school (5 miles), plug it back in, run errands (20 miles), plug it back in, run to my parents' house (35 miles), etc., etc., day in and day out?
Thank You!
Regarding question #3, IMO it’s better to run in EV for all of these short trips even if it means charging the battery frequently. Short trips ICE powered are hard on the engine, especially if it doesn’t have time to fully warm up. Luckily, the 2.5 ICE in the R4 has both direct and port injection, reducing the possibility of Direct Injection engine carbon fouling.
 

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21 Rav4 Prime SE with a little brother 95 LJ70 diesel
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Fine looking Prime!

I was under the impression that during very cold conditions, there was constant drain on the system to keep the battery warm while plugged in?
 

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Thank you !,,smaller than my highlander but feels bigger , on the cold,,,,More reason to keep it plugged in, I would think - not sure how the system " conditions" the batteries in the cold , only that batteries drain faster, the colder it gets
 

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21 Rav4 Prime SE with a little brother 95 LJ70 diesel
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Yes battery capacity is lower in the cold, electric seats and steering wheel plus heat pump eats up juice. Batteries also are less efficient at supplying power at low temps. You will learn to use the remote heat mode while plugged in to prewarm the car in the cold but when its gets real cold the heat pump can only do so much so switch it to HV to get some engine heat.
 
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