My new Juicebox Pro 40 seems to take a lot longer time to charge than Nissan's Aerovironment

My Nissan Leaf Forum

Help Support My Nissan Leaf Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

wtdedula

Active member
Joined
Sep 10, 2017
Messages
38
Hi All;
I just got my new Juicebox Pro 40 today and tried it out. My 2015 6KW Leaf was charged up to about 89% when I started charging and after about 45 minutes, I decided to go in the car and see how much % charge remained. It was stuck on 98% for the longest time - maybe 10 minutes. Is this normal ? The few times I charged at Nissan Showrooms, it didn't seem to take nearly this long as it was nearing the end of its charging cycle using their Aernvironment charger. Even though it's overpriced, I'm thinking of returning the Juicebox and getting the Aerovironment unit.

Tim
 
Maybe the car was doing some cell-balancing. From the way you describe the situation, the amperage of the EVSE is probably not the issue. The vehicle tapers down the charge rate as the SOC nears full.
 
As Nubo noted, the charge rate probably tapered to allow cell balancing. I believe the Juicebox has adjustable output so you might want to verify the setting. Normally, the setting should be 80% of the supply circuit breaker rating (40A output for 50A breaker, 32A output for 40A breaker, 24A output for 30A breaker). The AeroVironment unit needs a 40A breaker and has a maximum output of 30 amperes.
 
Time from low SoC for an hour. That will be the EVSE rather than the battery or OBC
If the battery starts out really cold, start your hour test after some 15 minutes of charging.
 
Yes, you cannot blame the plug in charger for charging time. It gives the car what the car is calling for.... You don't return the charger because it may be protecting your battery....

Starting at 89%, is a very high starting charge point, and may actually be bad for the battery according to what the manual says... something like, "do not charge when the battery is at a high level of charge."

Better to start your hour of charging time at 30-40%. I bet you it will charge at 25-35% capacity per hour.
 
wtdedula said:
Hi All;
I just got my new Juicebox Pro 40 today and tried it out. My 2015 6KW Leaf was charged up to about 89% when I started charging and after about 45 minutes, I decided to go in the car and see how much % charge remained. It was stuck on 98% for the longest time - maybe 10 minutes. Is this normal ?
The behavior you describe is normal when charging to 100%. It can take maybe an hour from around 95 or 96% on the dash display until the car stops.

On 2013 to (AFAIK) 2017 Leafs, when the car's near full, you'll see a taper then usually 3 bounces, sometimes 2, see http://www.mynissanleaf.com/viewtopic.php?p=490435#p490435.

If one charges to 80% (the option was removed on model year 2014+ US Leafs), power is cut abruptly. There's no ramp down nor bounce.
powersurge said:
<span>Yes, you cannot blame the plug in <a href="http://www.amazon.com/s/?field-keywords=electric%20vehicle%20charger&tag=myelecarfor-20" class="interlinkr" target="_blank">charger</a> for charging time. It gives the car what the car is calling for.... You don't return the <a href="http://www.amazon.com/s/?field-keywords=electric%20vehicle%20charger&tag=myelecarfor-20" class="interlinkr" target="_blank">charger</a> because it may be protecting your battery....</span>
First off, the OP bought an EVSE, NOT a charger. See http://www.mynissanleaf.com/viewtopic.php?p=262630#p262630. J1772 (for L1 and L2 AC charging) EVSEs have no knowledge of the state charge of the battery. It doesn't "protect" the battery since it know nothing about it. The car's on-board charger (not the EVSE) is doing the ramping down.

Please see https://openev.freshdesk.com/support/solutions/articles/6000052074-basics-of-sae-j1772 and http://www.sae.org/smartgrid/chargingprimer.pdf. The EVSE tells the car the max amperage it can draw via pilot signal and the car is supposed to obey and draw no more than that.
 
Nick Sayer has a device that will read the pilot and show what the EVSE will supply. Both units are limited to the car charger needs. An Upgraded leaf will draw 27.5A from either the 30A Aeroenvirement or the 40A JuiceBox. In both cases the excess is ignored. The same would hold for a Volt. In that case the charger would take 14A and ignore the rest. The car sets the current and as long as there is enough the excess is ignored.

If you are in the Anaheim area I would be happy to read your EVSE's with Nick's unit.
 
So informative everyone - Thanks. I will run some more tests though next time I'll let my battery get down to 20% or a bit lower. Everyone seems to have the same message - it's not the EVSE but the car that determines the charge time.

Tim
 
The link is to a screenshot of the JuiceBox app on my phone showing my charging yesterday.
The green graph shows the charge speed dropping toward the end of the charge session. I think I unplugged at over 90%, I usually aim for 80%.
https://flic.kr/p/213vJMS
 
wtdedula said:
So informative everyone - Thanks. I will run some more tests though next time I'll let my battery get down to 20% or a bit lower. Everyone seems to have the same message - it's not the EVSE but the car that determines the charge time.

Tim

To clarify, charge rate is determined by both devices. The EVSE "advertises" its maximum rate, and then the car's charger will use that rate as its upper limit. Some EVSE have adjustable output so it's possible that a 40A unit could be set to 16A, for example and then the LEAF would not exceed 16A. But regardless of the upper limit, the car's charger will be trickle-charging the pack by the time it hits 98%.
 
I really know nothing about the JuiceBox but the OpenEVSE defaults to 16A. It might be that the JuiceBox was set lower than the 30A Aeroenvirement unit. With OpenEVSE it is a menu item to set the current. On the basic JuiceBox units I built it was a pot. I think on the deluxe units it is done through wi-fi. As I said I am ignorant of the current JuiceBox's
 
Right, the JuiceBox can be set to limit the charging current. Set it to at least 28A if you want to maximize for your Leaf, and use 32A if you also have an EV with a 7.2kW charger.
 
Back
Top