Electric Vehicles/Charging/Short
Electric Vehicles functionality, day-to-day, is based on it having enough range to do what you need to do. Urban commuter cars (with your own parking/charging spot) don't need much range or charging speed -- but cross-country road trips need more range, faster charging and more chargers.
A lot of specs are confusing, and misleading. They give you theoretical max charging speed (or power) when you're limited by other things (car, car battery, etc). But it's a starting to point to know relative capabilities, even if the absolutes are lower and more nuanced.
North America Charging Connectors[edit | edit source]
The basics are you have these connectors (CHAdeMO and Magne Charge are legacy only):
| Country | Type | Names | Speed | Connector |
|---|---|---|---|---|
| U.S.
2007 |
AC | (Type 1) J1772 |
Level 1 = 1.4Kw - 1.9Kw (120v@12A w/15A circuit up to 12v0@16A w/20A circuit) Level 1+ = 2.8Kw (120v@24A w/30A circuit - optional / not in spec) Level 2 = 7.6Kw - 19.2Kw (240v@32A w/50A circuit up to 80A w/100A circuit) |
 |
| DC | CCS1 Supercharging |
Level 1: 36Kw Level 2: 72Kw Level 3: 400Kw (400Kw is theoretical, 350Kw is delivered) |
 | |
| Tesla | AC | Tesla | Level 1 = 1.4Kw - 1.9Kw (120v@12A w/15A circuit up to 12v0@16A w/20A circuit) Level 1+ = 2.8Kw (120v@24A w/30A circuit - optional / not in spec) Level 2 = 12Kw - 19.2Kw (240v@32A w/50A circuit up to 80A w/100A circuit) Level 2+ = 277v (3 phase commercial) |
 |
| DC | v1 = 72Kw (Urban / in-malls, etc) v2 = 150Kw (shared between 2 stalls) v3 = 250Kw (300Kw announced) | |||
| Japanese Cars (2010) |
AC | (Type 4) CHAdeMO Mostly Nissan Leaf |
Level 1 : up to 6-7Kw home units (max) Level 2 : ≈22Kw for Nissan Leaf by implementation (43Kw by spec) |
 |
| DC | v1 : ≈50Kw by implementation v2 : 200Kw, 400Kw (800Kw future): none implemented in U.S. |
Theory and practice[edit | edit source]
| 🗒️ MATH |
|---|
| AMPs x Volts = Watts. Thus 110v @ 12A = 1.3Kw, 220v @ 50A = 12Kw and 800v @ .3A = 250Kw |
Those specs are nice, but in the real world, what does all that mean?
For the most part the Level 1 (110v, normal wall outlet) and Level 2 (240v, Clothes Dryer, Dedicated home chargers, or what you find at Grocery Stores and malls) is not going to overtax the batteries/systems which are designed for peak Level 3 / DC SuperCharging at MUCH higher amounts of power. However, the SuperCharging is completely able to overpower your car's batteries, so you'll never get near the theoretical peak performance (for long).
- On Level 1 charging, you might think 120v @ 20A = is 2.4Kw... but in truth, a 20A circuit breaker, will be throttled by the charger/car to about 16A (1.9Kw) and most people only have a 15A breaker throttled to about 12A (1.4Kw), or about half of theoretical.
- On Level 2 changing, a Chevy Volt and Spark do about 3.3Kw, the Nissan Leaf does about 6.6Kw, but a Tesla can do like 20Kw -- but most places are going to deliver less than that.
- Supercharging can in theory do 250Kw or more... but cars will only take that for about 5 minutes when your battery is low. As it charges it heats up, and keeps dropping the rate of charge until you get to about 50Kw by the time you're up to 90% charge.
Real World Time[edit | edit source]
So users don't care about specs like kilowatts, they care about time (how much time does it take to charge). So instead of following the engineers, fans and geeks, I use the more common sense average miles per hour of charge (M/H). Here's a table with very loose guidelines on what it'll take to charge for the next dash.
| Country | Type | Names | Charging Speed | 20-80% Fill ( ≈200 miles) |
|---|---|---|---|---|
| Both | AC | J1772 | Home 110v = 2MPH Destination = 20-30MPH Home 220v = 44MPH |
10 hours 7 Hours 5 hours |
| CCS1 | DC | CCS1 | L1 : 100 M/H L2 : 200 M/H L3 : 400 M/H |
2 hours 1 hour 30 minutes |
| Tesla | DC | Tesla | v1 = 250 M/H v2 = 350 M/H v3 = 400 M/H |
45 minutes 35 minutes 30 minutes |
If you're trying to fill up to 100% and you have a 300-mile range, figure about an hour (+/- a few minutes). And if you're going shorter, you can divide accordingly.
EV road-trippers learn how to use their cars charging, driving until their battery is low, then only giving it enough charge to get to the next station (+ say 10-20% safety margin). It starts working out to about 30-40 minute breaks every 3 hours or so, maybe a little longer if you get a meal while it charges -- which is not much worse than an IC (Internal Combustion) for practical road trips.