Level 1 vs Level 2 vs Level 3 EV Chargers: What are the Differences?

If you’re going to drive an electric vehicle (EV), you’re going to need to recharge it. That can get a little complicated if you're not clear on how the different charging options work for electric vehicles. Here's a quick guide to the terms to know and the three EV charging levels you need to know.

What Are EV Charging Levels, Anyway?

Charging levels L1, L2, and L3 are three general terms that refer to how fast you can charge your EV battery.

Think of charging your EV like filling up a pool. You probably wouldn’t use a fire hose to fill a kiddie pool or a standard garden hose to fill an inground pool. Recharging an EV is kind of like that: It can take minutes to days, depending on the car's battery capacity, electric vehicle supply equipment (EVSE), and vehicle on-board charger (OBC) capabilities. In other words, how you charge your EV is similar to understanding the size of your EV's 'pool' and the 'hose' used to fill it.



Here are the basic terms to know:

The Charging Station Equipment: EVSE

Charging station power is rated in kilowatts (kW). Higher kW numbers mean faster charging. If the charging station is rated in amps (A), kW can easily be calculated by multiplying by voltage (V) and dividing by 1,000.

The 'Hose' for Receiving Power: OBC

The EVSE delivers power to the OBC, which can only deliver up to its maximum rating to the battery. For example, a 12-kW charger can only charge a maximum of 7.2 kW if the OBC is rated for 7.2 kW, but it may only charge at 6 kW if the battery is too hot or cold.

The Car's Capacity (or Pool): kWh

Battery capacity is given in kilowatt-hours (kWh).

Typical charge time is a simple matter of dividing capacity by power. For example, restoring 50 kWh at 5 kW will take about 10 hours. At 150 kW, it’s about 20 minutes, but at 1.4 kW, it’ll need about 35 hours to finish.

Level 1 Charging Explained

Every EV comes with a free L1 charge cable. It’s universally compatible, doesn’t cost anything to install, and plugs into any standard grounded 120-V outlet. Depending on the price of electricity and your EV’s efficiency rating, L1 charging costs 2¢ to 6¢ per mile. 

The L1 charger power rating tops out at 2.4 kW, restoring up to 5 miles per hour charge time, about 40 miles every 8 hours. Since the average driver puts on 37 miles per day, this works out for many people.

The L1 charger can also work for people whose workplace or school offers L1 charge points, allowing their EVs to charge all day for the ride home.

Many EV drivers refer to the L1 charge cable as an emergency charger or trickle charger because it won’t keep up with long commutes or long weekend drives.

Level 2 Charging Explained

The L2 charger runs at higher input voltage, 240 V, and is usually permanently wired to a dedicated 240-V circuit in a garage or driveway. Portable models plug into standard 240-V dryer or welder receptacles, but not all homes have these.

Level 2 chargers cost $500 to $2,000, depending on brand, power rating, and installation requirements. Subject to the price of electricity and your EV’s efficiency rating, L2 charging costs 2¢ to 6¢ per mile.

Level 2 charging stations are universally compatible with EVs equipped with the industry-standard SAE J1772 or “J-plug.” You can find public-access L2 chargers in parking garages, parking lots, in front of businesses, and installed for employees and students.

Level 2 charging stations tend to top out at 12 kW, restoring up to 12 miles per hour charge, about 100 miles every 8 hours. For the average driver, putting on 37 miles per day, this only requires about 3 hours of charging.

Still, if you’re on a trip longer than the range of your vehicle, you’re going to need a quick top-up along the way that Level 2 charging can provide.

Level 3 Charging Explained

Level 3 chargers are the fastest EV chargers available. They typically run on 480 V or 1,000 V and aren’t typically found at home. They’re being better suited to high-traffic areas, such as highway rest stops and shopping and entertainment districts, where the vehicle can be recharged in less than an hour.

Charging fees might be based on an hourly rate or per kWh. Depending on membership fees and other factors, L3 charging costs 12¢ to 25¢ per mile.

Level 3 chargers are not universally compatible and there is no industry standard. Currently, the three main types are Superchargers, SAE CCS (Combined Charging System), and CHAdeMO (a riff on “would you like a cup of tea,” in Japanese).

Superchargers work with certain Tesla models, SAE CCS chargers work with certain European EVs, and CHAdeMO works with certain Asian EVs, though some vehicles and chargers may be cross-compatible with adapters.

Level 3 charging stations generally start at 50 kW and go up from there. The CHAdeMO standard, for example, works up to 400 kW and has a 900-kW version in development. Tesla Superchargers typically charge at 72 kW, but some are capable of up to 250 kW. Such high power is possible because L3 chargers skip the OBC and its limitations, directly DC-charging the battery.

There is one caveat, that high-speed charging is only available up to 80% capacity. After 80%, the BMS throttles the charge rate significantly to protect the battery.

A Final Plug About Chargers

In the end, finding the right charger will come down to the capabilities of your EV and how much you want to drive it. Generally, do not count on the L1 charging cable that came with the vehicle, unless you don’t drive much.

Most EV drivers need access to an L2 charger, whether it’s at home, work, school, or some other place. Home is the best place for an L2 charger, though, unless you have a dependable reserved space elsewhere. An L2 charger that can charge your vehicle in 8 hours is going to serve you well, but expect longer charge times in deep winter and the dog days of summer.

Finally, if you’re heading outside of your normal commute, download an app to locate and pay for the right L3 charging station for your vehicle.

Reposted from: https://www.lifewire.com/ev-charging-levels-explained-5201716