I'm trying to charge as fast as possible on my existing electrical circuit. I have a 20 Amp 120v outlet (rather than the standard 15A). Is it possible to get a charger that will utilize this extra headroom? As I understand it, Level 2 chargers require a higher voltage outlet and Level 1 chargers are built for 15A circuits.
OP consider this, instead of spending roughly ~$410 shipped to charge at about ~1920 watts with that expensive EVSE unit, spend ~$300 to ~$400 on installing a 240v NEMA 14-50R. Now use your Toyota OE 120v* EVSE at 240 volts with a quality 10 AWG adapter. You'll be charging at ~2880 watts for roughly the same price, your new charge up time will be about ~2:28 minutes. Any future EV that you purchase will also use your smartly installed NEMA 14-50R. Rob43 * Works Flawlessly.
Something that you may want to research is any incentives that MAY be offered in your area. I know (I think) some States or utilities offer various incentives. When I had my Level-2 station installed in 2016 I qualified for both Federal and Oregon programs (both have ended, I think).
The onboard charger is 3.3 kWH, right? So any combination of volts & amps that provide at least 3.3 kWH to the onboard charger will yield the quickest charge.
Yes. 12A @240V Aftermarket can get 16A @240V which is roughly a reduction of 30min in charging time (2:30 vs 2:00). But an increase in cost of having to get a separate cable.
I was just about to make the same comment/question. On a 120 volt circuit, the Prime is designed to charge at 12 amps or less. On a 240-volt circuit, the Prime will draw up to 16 amps. To allow the Prime to be plugged into a 120-volt circuit which may not have 12 amps available because of other electrical devices sharing the circuit, the Prime's charging current demand can be set to 8 amps. The time it takes to fully charge the Prime's traction battery will be longer at the lower current setting. At 120 volts, the Prime's charging circuit will drawn no more than 12 amps, regardless of whether it is plugged into a 15-amp or 20-amp circuit. Even if you charged your Prime by plugging it into a 20-amp circuit with a 3rd-party 120-volt device rated for a higher current, it will not draw any more current than it will when using the EVSE charging cord which came with your Prime. If you want to charge faster, you must use a 240-volt Level 2 EVSE connected to a 240-volt supply. And, with that configuration, your Prime will still limit itself to 16 amps -- even if your level 2 EVSE is capable of delivering 40 amps or more. Consider that power (watts) = volts x amps: 120 volts x 8 amps = 960 watts; 120 volts x 12 amps = 1440 watts; and, 240 volts x 16 amps = 3840 watts. So, if you plug your Prime into 120 volts at 8 amps for one hour, you nominally will add 0.96 kilowatts hours (kWh) to your battery. Similarly, at 120 volts at 12 amps, in one hour you will add 1.44 kWh. And at 240 volts at 16 amps, in one hour you will add 3.84 kWh. The time to fully charge your Prime (approximately 8300 kWh) will be inversely proportional. i.e., higher current x higher voltage = faster charging. 8300 kWh / 240 volts x 16 amps = 135 minutes (2 hours, 10 minutes) 8300 kWh / 120 volts x 12 amps = 345 minutes (5 hours, 45 minutes) 8300 kWh / 120 volts x 8 amps = 519 minutes (8 hours, 39 minutes) And, before anyone starts comparing their actual charging times with the above calculations, consider: 8300 kWh is just an approximation of the Prime's charging cycle; the efficiency of the charging process is affected by the charging voltage; the battery temperature; the battery age and condition; and, many other factors. These calculations are intended only to provide a reasonable representation of the relative times needed to fully charge a Prius Prime at various voltages and currents.
I think I know: Any EVSE and Charging circuit (in the car) will use the lowest advertised Amperage. The included EVSE cable advertises 12 Amps. (max) Rob43's and other 240 to 120 Volt adapters do not change that. The Prime's Charging circuit normally charges 16 Amps at 240 Volts, and can be set to charge at 8 Amps. SAE J1772 - Wikipedia Old Bear makes the claim that the Prime can only charge 12 Amps at 120 Volts instead of 16 Amps and I am not sure I know that. A 16 Amp, 120 Volt EVSE is pretty rare, but i would not be surprised if it did not charge faster than the included cable. The ability to know the Voltage would add complexity I am not sure exists in the Prime and does not seem to be in the standard. Now I wish I had a 16 Amp 120 volt charger and a Prime, and a car that took a higher amperage. I would try to make Bob Wilson quality graphs.
Based on ONE report that I read somewhere on this forum, the PriusChat poster stated that his aftermarket 16 amp / 240 volt EVSE unit would charge up his Prime "a little bit" faster when plugged into 120 volts as I remember it. The math says "if" this worked, it would shave roughly 1 hour off of the charging time. This would be a big waist of money... Rob43
It was a 16 amp something, but this was far from ground braking news at the time, so I'm not sure... Rob43
Ah... truth in advertising. Actually, the EVSE "advertises" the maximum current it can deliver. There is no circuitry inside an EVSE to limit current. Once the EVSE completes handshaking with the vehicle, the power line is connected directly to the vehicle through simple switched contacts. Consider for a moment that when the Prime is plugged into a Level 2 charger which "advertises" 40 amps available, the Prime still draws a maximum of no more than 16 amps. This is a function of the Prime's internal charging circuit and is designed to optimize the charging of the traction battery without damaging any of the individual cells. Please notice in my previous post that I am not making the claim. The excerpt is from the Toyota manual and says that, on a 120-volt EVSE, the Prime will charge at 12 amps or less. Also, notice that the charging current can be set to a lower number using the Prime's software but there is no way to set it to a higher number -- unless, of course, you hack the car's software. And that would be bad because the hardware (battery configuration) is designed so that the charging voltage is distributed between specific clusters of individual cells depending upon whether the charging voltage is 120v or 240v. I agree that experimentation and the scientific method are an excellent way to prove of disprove a hypothesis. If you assemble the apparatus for this experiment, I would enjoy learning of your results. Possibly you will confirm your suspicion that the Prime has an undocumented feature.
'i would not be surprised if it did not charge faster than the included cable' my elementary school english teacher is rolling in her grave.
For the sake of argument, consider the idea that "Home Power Source" in the manual may merely refer to the included EVSE cable that comes with the Prime. Then we agree in every detail. The included EVSE cable always claims it can do 12 Amps. The internal charger in the Prime can do 16 Amps, but has software that can limit it to 8 Amps. When using the Included cable (at 120 Volts or 240 Volts) max Amperage is 12. When using virtually any L2 charger the max Amperage is 16. The protocol mentions ventilation signalling, which may reduce Amperage if the Car detects overheating. (It almost reads like this is at startup of charging) Certainly the car has an 8 Amp setting. Unfortunately, a 16 Amp Level 1 charger is rarer than hen's teeth. So we may be forced to agree to disagree, having no way to prove either interpretation. While I am a huge fan of the Scientific Method, i am not about to buy a Prime, a Model 3 and a entirely inadequate Level 1 charger for them! (I have every hope of dying still owning my Prius v)
