Electric Vehicles/Charging/Long
Electric Vehicles functionality, day-to-day, is based on it having enough range to do what you need to do.
- If it's just an urban commuter car (to/from work/grocery store), and that's about 50 miles a day, then the Nissan Leaf with its original 73 mile range (now up to 100) is plenty -- assuming you can charge at night, it'll always have enough range to do what you bought it for -- and be more convenient than an IC (Internal Combustion / Gasoline Car), in that use-case. If you can charge at work, or while shopping, and use HOV lanes, that's just gravy. (I knew a lot of happy owners).
- If you don't have at-home charging, then you miss the best feature of an Electric Car (always having a full tank). So in some areas where you don't have your own parking spot, they may never be as convenient as IC's.
- If it's not just a second car, and you want to road trip over it's range or you're a heavy driver (say 250 miles in a day), then the charging speed and infrastructure matter a lot. And there's a cross-over point, where fast filling (and availability of refueling) is going to be in IC's favor for decades.
When you're driving more than a couple hundred miles per day and need to either charge on the go, or emptying the charge and wanting to make sure it'll be charged by morning -- then you kinda need to know this stuff. (At least in concept). Gasoline has much higher energy density, and much more infrastrcuture. EV's are trying to use software to get around some of that (with route mapping), and it mostly works good enough. But people start with a lot of domain knowledge about IC's -- like range, refill times, safety (don't smoke while filling, or put your cigarette out in the gas tank), and so on. New knowledge for EV's feels foreign and overwhelming because it's new.
A lot of specs are confusing, and misleading. They give you theoretical max charging speed (or power) of the cabling/chargers... when you're really limited by the practical max charging speech -- which is based on your car's batteries, State of Charge (SoC), capabilities, and charging profile (software based on battery chemistry and where it is in its lifecycle). But it is a good starting to point to know relative capabilities, even if the absolutes are a little 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. | |||
GM EV1
(1996) |
Inductive | Magne Charge J1773 |
Level 1 = 1.2Kw standard (120v AC) Level 2 = 6.6kW |
Other Charging Connectors[edit | edit source]
This is the rest of the world's charging.
Country | Type | Names | Speed | Connector |
---|---|---|---|---|
Japan | AC | (Type 4) CHAdeMO Mostly Nissan Leaf |
Level 1 : up to 6-7 kW home units (max) Level 2 : ≈22 kW for Nissan Leaf by implementation (43Kw by spec) |
|
DC | v1 : ≈50kW v2 : 200 kW v3: 400kW Future: 800 kW | |||
EU | AC | (Type 2) Mennekes |
Level 1 = 3.7 kW (230v@15A w/15A) Level 2 = 7 kW (230v@30A) Level 3 = 22 kW (3 phase) Level 3+ = 43 kW (Renault Zoë) |
|
DC | CCS2 | v1 : 50 kW v2 : 150 kW v2 : 300 kW |
||
China | AC | GB/T 20234.2-2015 | 220v/440v @ 32A : ≈ 7kW - 14kW | 7 Pin |
DC | 750v | 9 Pin |
Evolution[edit | edit source]
🗒️ V2G |
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CHAdeMO cars/connector even had the ability to sell back battery energy to the grid during peak (Vehicle to Grid or V2G), using your car as backup power for the grid. However, not many people want to wear out their car's batteries faster (or give up range when they might need it), all to make/save a few dollars on electricity. So that feature was more a test case than often used.
CSS added it as well, in theory. But it too hasn't been widely implemented. (Some pilot programs). It looks like the Ford F-150 lightning (EV) will implement it, at least to replace a generator for power outages. Tesla discussed it as an option early on, but they had their PowerWall dedicated battery for that, so didn't implement it for their cars. |
- 1996 - GM's EV1 was first modern EV in 1996[1]with Delco developed "Magne Charge" (J1773 connector)[2], it was an inductive charging paddle system that was slow (1.2Kw standard, or 6.6kW optional charging): it took up to 24 hours to charge the 60-mile range EV1. But it was safe, and the inductive charging would even work submerged in water. The Chevy Electric S-10 pickup and Toyota RAV-4 EV pilot programs also used that connector for a while. But it never got widespread adoption and is dead tech.
- 2001 - California wanted to go to EV's and from inductive to conductive charging, so supported the SAE designed the J1772 SAE connector in 2001... to be implemented in 2006. It didn't get any adoption until 2010 in the Nissan Leaf (which quickly moved to CHAdeMO), and the 2012 plug-in Hybrid Chevy Volt: both small battery vehicles. It was originally 6.6Kw, but it got upped in 2009 to 19.2 kW making it more practical.
- 2003 - Tesla was founded in 2003, but it took until 2008 to bring the Tesla roadster (Darkstar) to delivery. 2,450 units was highest volume EV sales, and it had a 53kWh battery (244-mile range), that required faster charging, so the Tesla charging was created. 2012 brought the Model S and a 85-100KkWh battery, and some modifications to the connector/charging was made, including introducing a SuperCharging network (with 150Kw DC charging) to support trans-continental road trips. Their connector is still smaller and more functional than competitors.
- 2010 - the first widespread adoption with the Nissan Leaf, they used the Japanese CHAdeMO (CHArge de MOve) connector in Japan (and later the U.S.) that became popular with Japanese makers. The Leaf had small batteries/range (24kWh/73 miles) and thus early CHAdeMO chargers were low-power by design. Their later superchargers were also low power (50Kw) in theory, but lower by the implementation (22Kw). While CHAdeMO fixed the specs in v2 to take higher speeds (200-400Kw, with 800Kw possible), other cars needed more power, so had leapfrogged CHAdeMO -- and nobody was going to implement the charging infrastructure without the cars that demanded it. Cars that used CHAdeMO didn't sell for a premium, nor need that high speed of charging. Thus Nissan (and other manufacturers) announced they are moving to CCS1 or CCS2. CHAdeMO is legacy with a practical limit of 50Kw, and dying out.
- 2012 - CCS was evolving to do high-speed DC direct charging. So they announced in 2012, they'd stick a DC pins (optional) on the bottom of J1772 in the U.S. (Type 1), or on the bottom of Mennekes connector in the EU (Type 2). So there was a lot of parallel/competing development.
In the end, Tesla has the most elegant and widest scaled solution in the early years of EV's (both connectors and charging networks). To this day, there are a few other electric charging networks, but none alone comes close to Tesla's reliability or scale. Even combined. But that will change. With National Regulations requiring CCS2 in EU and other places, and multiple other vendors jumping on CCS, and their charging network fleshing out, Tesla's proprietary connector may be replaced in the coming decade. But for now, if you want an EV that you can drive across country, Tesla is still the best option.
China is confusing as heck to research (without reading Chinese). As near as I can tell, they have a standard for how to talk between car and charging, but not on cabling (beyond requiring it to be female connectors in the car, instead of male in the rest of the world). Or at least they were far later to the game. Tesla has some chargers there, and a lot of their companies went to battery swapping (possibly to get around the confusing cabling standard)?
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 a bit confusing. In the real world, what does all that mean? Well, it depends.
The manufacturers give you all these specs -- and they are good for relative measurement -- in that bigger is faster (or less time to charge), and that's better. However, they do NOT hold up in the real world in absolute numbers.
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).
Remember: we're talking about what the connectors/cables can handle as power... but your car controls how fast it actually charges -- and that's not based on how much power the cable/charger can deliver -- it is based on how much the car wants to let it charge. Because cables, inverters, batteries release heat as they charge (or discharge), they have limits and will not run at peak all the time. Batteries are the biggest bottleneck (limiter), and they can take more or less power based on temperature and their SoC (state of charge) -- the lower in power they are, the hungrier (and more able to take power), and the closer to full and the warming (the longer they've been charging) the slower they are. And your cars computer tells the charger how fast to charge (how much power they can take).
So when we look in practice, you get things like:
- 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, that's some pretty dramatic differences. But then the Tesla's have more range/battery, so can take less per mile of range, but nearly as much to charge the whole thing.
- Supercharging gets more dramatic:
- you can in theory do 250Kw or more... but Tesla will only do 250Kw for about 5 minutes, and that's if your battery is 10% SoC or so, then as the charge percent goes up (and the batteries heat up) the rate of charge drops down to about 50Kw by the time you're up to 90% SoC.
- The Hyundai Ioniq seems to be the best at charging -- it charges a little slower at the start, but sustains that rate longer. End result is a few minutes faster at most. Audi/Porsche can surge a litte higher than Tesla, but drop off quicker, and take longer.
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).
Even then, most of the time, you're charging overnight at home -- and you don't really care, as long as you wake up with a full charge every day. When it matters is how much free charge can you get at work (on level 2 / destination charging). Or more importantly, when you're road tripping that you care. And then you're doing splash and dash -- you're taking a break every 3 hours, and getting about 200 miles (3 hours of driving range). And how long does that take?
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.
These numbers are smaller (slower) than spec -- because the specs usually talk about the best case, and not the average case. When you first plug in, the car (batteries) can take a lot (best case), then the batteries start heating up and the rate of charge slows. The worst case is from 90-100% after a full charge, where 250 kW stations are actually only feeding about 50 kW in (or 1/5th best case) -- but most people don't need that to get to the next charging station and will leave at 80%.
- ↑ GM (Chevrolet): Press Release
1996 - ↑ Wikipedia: Magne Charge
- ↑ QuoteInvestigator