The Difference Between Level 1 & 2 & 3 EV Chargers

With the popularity of electric vehicles, it has become indispensable to understand the importance of charger ratings. In this article, we'll take a look at how charging levels affect electric vehicles and explain the differences between the different levels.

If you own a plug-in vehicle or are considering purchasing one, you've probably heard terms related to charging speeds such as "Level 1," "Level 2," and "Level 3." Level 3 is further categorized as DC fast charging and Tesla Supercharging. The higher the charging level, the faster the charging process, as more power is transferred to the vehicle. It is important to note that different EVs charge at different speeds at each level, this is because each EV can receive different levels of power from the EVSE (Electric Vehicle Supply Equipment).

When an EV is connected to a power source, a series of communication processes take place between the charger and the vehicle. Basically, the vehicle asks the charger how much power it can provide and then asks the charging station for the maximum amount of power it can provide and that the vehicle can accept.

The vehicle always determines the amount of power it will accept, so you don't have to worry about plugging into a charging station that provides more power than the electric car can handle. The vehicle will limit the power provided by the charger to ensure safe charging.

Please note that the charging level numbers are not perfect either, but they are a common industry standard.

Here, we explain what these levels mean and how they affect EVs. Keep in mind that regardless of the charging method, batteries charge faster when empty, slower when fully charged, and the charging rate is also affected by temperature.

All of the above charging levels apply to Tesla and other brands of EVs. Although Tesla uses a proprietary connector, the industry has agreed on an international standard that regulates charging for all electric vehicles, called J1772.

In what follows, we'll explore each charging level in more detail to help you better understand the EV charging process and options.

Level 1 Charging

Level 1 charging is a type of electric vehicle (EV) charging that utilizes a standard household outlet with a voltage of 120 volts. It is often referred to as "trickle charging" because it provides a slower rate of charging compared to other levels. On average, Level 1 charging adds 3-5 miles of range to an EV or plug-in hybrid electric vehicle (PHEV) per hour of charging.

The charging time for Level 1 depends on the vehicle's efficiency and its electric range. For modern PHEVs with an electric range of 15-60 miles and EVs with a range of 150-400 miles, it could take around 30 hours to fully replenish 150 miles of range at the fastest Level 1 charging rate. The efficiency of the vehicle plays a significant role, as less efficient vehicles will get less range from the same amount of electricity compared to more efficient ones.

Automakers typically include a small Level 1 charger with their plug-in vehicles. This charger consists of a small box or cylinder with a short cord and a grounded household plug on one end, and a longer cord with a pistol-grip connector on the other end, which plugs into the car. This charger is technically called an Electric Vehicle Service Equipment (EVSE) or Supply Equipment. Although Level 1 charging is considered the least useful charging level, the designation remains relevant because there is minimal difference in the amount of power these chargers provide. Typically, Level 1 chargers are limited to 10 or 12 amperes of current to accommodate usage on a 15 or 20-amp circuit, which may also power other electric outlets and appliances. While there is a distinction between 10 and 12 amps, the charging rate is still relatively slow. It is worth noting that the Level 2 description further highlights how the level designation can be arbitrary.

For PHEVs, Level 1 charging is often sufficient due to their smaller battery size and the presence of a gas backup system. However, if affordable, it is recommended to consider Level 2 charging. Level 1 charging does not provide enough power to preheat or precool the cabin in extreme temperatures while still connected to the grid, which is crucial for preserving battery charge and range.

Some automakers are now including a more robust, standard charger with their EVs, capable of both Level 1 and Level 2 charging. These chargers come with interchangeable short pigtail cords featuring different types of plugs to determine the operating level. Tesla has been employing this approach with their Mobile Connector for years, and other manufacturers, such as Ford with the Mustang Mach-E, are following suit. These chargers often have a maximum rating of 32 amps (for use on a 40-amp circuit) and may offer more than enough charging capability for most owners.

Level 2 Charging

Level 2 charging is the most useful type of charging for electric vehicles (EVs) at home. It is faster than Level 1 charging and provides a more satisfying ownership experience. While Level 1 chargers use a standard household outlet with 120 volts, Level 2 chargers operate at 240 volts. This is the same voltage used for appliances like clothes dryers and electric ovens.

The charging speed at Level 2 depends on two factors: voltage and current. The voltage is fixed at 240 volts, but the current can vary. Level 2 chargers can support currents from 12 to 80 amps. The actual charging speed depends on the specific vehicle and charging unit used. Charging for one hour at Level 2 can add anywhere from 5.5 to 60 miles of range.

Level 2 chargers come with different amp ratings, such as 12, 16, 20, 24, 32, 40, 48, or 64 amps. Some chargers can also be adjusted to lower current levels to accommodate less robust electrical circuits.

Many automakers now include combination Level 1/2 chargers with interchangeable cords. These cords can be plugged into a standard household 120-volt outlet or various styles of 240-volt outlets. For example, Tesla provides its customers with a Mobile Connector rated at 32 amps, which can be used with a 240-volt outlet. This setup can add approximately 30 miles of range per hour for a small Model 3 sedan or 20 miles of range per hour for a Model X large SUV. Other Tesla models offer similar charging rates.

It's important to note that Tesla chargers are not inherently faster than other chargers with comparable ratings and different connectors. The perceived difference in speed is due to the higher efficiency of Tesla vehicles, meaning they gain more range for the same amount of energy.

In summary, Level 2 charging is the most recommended option for charging EVs at home. It offers faster charging speeds and a more convenient ownership experience compared to Level 1 charging.

Level 3 Charging

Level 3 chargers, also known as DC fast chargers or superchargers, are the fastest charging option for electric vehicles (EVs) available today. They use direct current (DC) to charge EVs much faster than Level 1 and Level 2 chargers. Level 3 chargers can fully charge an EV in under an hour, making them ideal for long-distance travel and road trips.

These chargers are commonly found alongside main thoroughfares and highways, making them accessible for EV owners who frequently take extended trips. However, it's important to note that not all EV models are compatible with Level 3 charging. Compatibility depends on the specific make and model of the vehicle.

Level 3 chargers are not as standardized as lower-level chargers. They require special components like a Combined Charging System (CCS) plug or a CHAdeMO plug used by some Asian automotive manufacturers. The availability and compatibility of Level 3 charging stations depend on the specific charging standards supported by the EV.

The charging fees for Level 3 chargers can vary, with some stations charging based on an hourly rate and others charging based on the amount of kilowatt-hours (kWh) consumed. The cost of Level 3 charging is generally higher than Level 1 or Level 2 charging due to the higher installation and maintenance costs associated with the infrastructure.

Level 3 chargers are typically found in high-traffic areas such as highway rest stops and shopping districts, where EVs can be recharged quickly. They are designed for commercial and heavy-duty EVs, but most passenger EVs can also use them.

These chargers operate at higher voltages, typically running on 480 V or 1,000 V, and are not typically found at home. They can deliver an impressive range of approximately 150-350 miles per hour of charging, depending on the specific charger and EV.

It's important to note that Level 3 chargers are not universally compatible, and there is no industry standard. The three main types are Superchargers (for Tesla vehicles), SAE CCS (for certain European EVs), and CHAdeMO (for certain Asian EVs). However, some vehicles and chargers may be cross-compatible with the use of adapters.

Level 3 chargers can provide high charging power, starting at 50 kW and going up from there. For example, the CHAdeMO standard can provide up to 400 kW, and a 900 kW version is currently in development. These high power levels are achieved because Level 3 chargers directly charge the EV battery with DC power, bypassing the on-board charger (OBC) and its limitations.

It's important to note that high-speed charging is only available up to 80% capacity. After reaching 80%, the charge rate is significantly reduced to protect the battery.

DC Fast Charging

DC fast charging, also known as Level 3 charging, is the fastest charging method available for electric vehicles (EVs) in the United States. Compared to Level 1 and Level 2 chargers, which use alternating current (AC), DC fast charging utilizes direct current (DC) power to charge EVs at a much faster rate.

One of the key advantages of DC fast charging is its incredible speed. EVs using DC fast chargers can achieve an impressive range of approximately 150-350 miles per hour of charging. This makes DC fast charging the perfect choice for EV owners who frequently embark on long-distance travels or road trips.

In the US, DC fast charging stations are commonly found along major highways, rest stops, and in public charging networks. This strategic placement ensures that EV owners have access to quick charging solutions during their journeys, providing convenience and peace of mind.

It's important to note that not all EV models are compatible with DC fast charging. The availability and compatibility of DC fast charging stations depend on the specific make and model of the vehicle. EV owners should check their vehicle's compatibility and charging capabilities before relying on DC fast charging as their primary charging method.

It's worth mentioning that the installation and maintenance costs associated with DC fast charging infrastructure are generally higher compared to Level 1 or Level 2 chargers. However, the speed and convenience that DC fast charging offers make it a valuable option for EV owners who need to quickly charge their vehicles during long trips.

While Level 3 chargers are not as standardized as lower-level chargers, there are different types of DC fast charging standards. In the US, the three main types are Superchargers (for Tesla vehicles), SAE CCS (for certain European EVs), and CHAdeMO (for certain Asian EVs). It's important to ensure that the EV and the charging station support the same charging standard for compatibility.

DC fast chargers generally start at 50 kW and go up from there. The charging speed can vary depending on the specific charger and the capabilities of the EV. It's important to note that after reaching approximately 80% capacity, the charging speed is significantly reduced by the EV's battery management system (BMS) to protect the battery's health.

In conclusion, DC fast charging provides unparalleled speed and convenience for EV owners who need to efficiently charge their vehicles during long journeys. With strategically placed charging stations along major highways, EV owners can easily access quick charging solutions to extend their range and enjoy worry-free travels. However, it is essential to check the compatibility of the EV model and consider the costs associated with DC fast charging before relying on it as the primary charging method.