- The Volvo PHEV has a 3.7 kW onboard charger.
- and Watts = Volts * Amps
- so the amps the car will draw: 3,700W/240V = 15.4A, or 3,700/120V = 30.8A. So it appears that yes, you could plug this car into a 40A 120V outlet – although I’ve never heard of one of these. lol. But you can see that a 20A circuit, at 240V, will supply all the power the charger can consume.
- How long will it take to charge? The car has a 18.8 kWh battery, with 14.7 kWh usable.
- 14.7 kWh * 1.10 (for heat loss) / 3.7 kW = 4.37 hours. So the car should fully charge, from 0% to 100%, in a bit less than 4 1/2 hours when using the 240V 20A plug/adapter.
- But if you charge with the 12A 120V adapter, this thing is designed for a 15A circuit, how long will it take? 12A * 120V = 1.44kW which is less than half speed. okay. 14.7kWh * 1.10 / 1.44 kW = 11.2 hours.
So, there’s your choice. Install a 240V 20A (NEMA 6-20) outlet and charge your PHEV up in 4 1/2 hours. Or just stick it in a standard 15A wall outlet and it will require just over 11 hours. I guess it depends on how long “overnight” is for you – and how earnest you are about EV’ing around the neighborhood 😉 I’m pretty sure the Volvo engineers sized this battery thinking about what “overnight” meant. The first generation Volvo PHEVs only had a 10.4 kWh battery – so it easily charged overnight.
a couple of notes: no matter how many AC amps you supply to the car the onboard charger can only accept 3.7 kW. And this is worth understanding. The high voltage battery in the Volvo PHEV is 400V DC. And to charge a DC battery you need to give it (just over) 400V DC – so the on-board charger is responsible for transforming 120 or 240V AC to 400V DC. So it’s actually a misnomer to call the “charging cable” the “charger”. Because the level 1 (120V AC) and level 2 (240V AC) charger is really onboard the car itself. This is true for all EV’s.
And that’s why the box on the wall, or the portable cable, is not a charger – but instead properly called an EVSE (Electric Vehicle Supply Equipment). woohoo.
What’s also interesting. only 78% of the PHEV battery is considered “usable”. presumably the other 22% is reserved to preserve capacity over time. This is pretty cool really – and should give us all some reassurance of the longevity of the Volvo PHEV. Note that a Volvo EX40, for example, apparently only reserves 3kWh of it’s 82 kWh battery. damn. the PHEV reserves 4.1 kWh!
There’s been some commentary recently about charging your PHEV to just 80%. But I guess now we know why the engineers designed it to go to 100% Because when you charge your PHEV to 100% it is only 80%. lol.