BLOG
  • Home
  • |
  • Electric Shock Showdown: AC vs DC EV Chargers

Electric Shock Showdown: AC vs DC EV Chargers

call me now
July 7, 2023

When charging an electric vehicle, the majority of public charging stations and home EV chargers use AC. AC charging is slower than DC charging, taking several hours to fully charge an EV. We’ll take a look at AC vs DC EV Chargers in this article.

On the other hand, DC charging is much faster, with some stations capable of delivering 80% charge in as little as 30 minutes. However, these stations are typically more expensive and less widely available than AC chargers.

One of the main differences between AC and DC charging is where the conversion from AC to DC occurs. With AC charging, the conversion happens within the vehicle. In contrast, DC charging involves an external charger that converts the AC power from the grid into DC power, which is then supplied directly to the vehicle.

It’s worth noting that not all EVs are capable of DC fast charging. While most modern EVs can accept DC charging, some older models may not have the necessary components to handle the high voltage and current involved.

Additionally, the charging speed can also depend on the capacity of the EV’s battery. A larger battery may take longer to charge, even with a fast DC charger.

AC vs DC EV Chargers

The EV Charging Ecosystem: Navigating the Different Types of Charging Stations

The EV charging ecosystem is a complex network of charging stations, each with its own set of advantages and limitations. For example, Level 1 charging, which uses a standard 120V AC outlet, is the slowest but most ubiquitous form of charging. It’s ideal for home charging, where time isn’t a pressing concern.

Level 2 charging, which uses a 240V AC outlet, is faster and more suitable for public charging. Many businesses and public spaces offer Level 2 charging stations, making it a convenient option for EV drivers on the go.

DC fast charging, also known as Level 3 charging, is the fastest form of charging and is essential for long-distance travel. DC fast chargers use a high-power DC current to quickly charge an EV’s battery, allowing drivers to get back on the road in a fraction of the time it would take with other types of charging.

However, while DC fast charging is convenient, it’s also more expensive and less widely available than other types of charging. Additionally, not all EVs are capable of accepting DC fast charging, so it’s important for drivers to check their vehicle’s capabilities before relying on this type of charging.

Another factor to consider in the EV charging ecosystem is the charging network. Some charging stations are part of a larger network, such as Tesla’s Supercharger network or the ChargePoint network, which provide additional benefits such as real-time charging monitoring and the ability to pay for charging through a single account.

AC vs DC: Understanding the Fundamentals of Electrical Currents in EV Charging

AC (alternating current) and DC (direct current) are the two main types of electrical currents used in EV charging.

DC current, on the other hand, flows in a single direction and is the type of current stored in EV batteries. While AC charging is slower, DC charging is much faster and is necessary for long-distance travel. DC charging stations, also known as Level 3 charging stations, use a direct current to quickly charge an EV’s battery, allowing drivers to get back on the road in a fraction of the time it would take with AC charging.

It’s worth noting that not all EVs are capable of accepting DC fast charging. While most modern EVs can handle DC charging, some older models may not have the necessary components to handle the high voltage and current involved.

EV charging curves 

When it comes to charging electric vehicles (EVs), AC and DC charging methods differ not only in their power source, but also in how their power output fluctuates throughout a charging session. This is reflected in the EV charging curve, which varies depending on the charging method used. For instance, in AC charging, the charging curve tends to be more gradual and steady, while in DC charging, the curve is typically steeper and faster. To put it simply, the charging curve reflects the rate at which an EV’s battery charges over time, and this rate can vary significantly depending on the charging method used.

AC charging curve

In AC charging, the power supplied to an EV remains relatively consistent throughout the charging session, with little fluctuation in the EV charging curve. This is because AC charging relies on a small onboard converter that can only handle a limited amount of power spread out over longer periods. As a result, the charging curve for AC charging tends to be flatter and less steep than that of DC charging. While this may mean that AC charging takes longer to fully charge an EV than DC charging, it also means that AC charging is generally less expensive and more widely available, making it a popular choice for many EV owners. However, it’s worth noting that advancements in technology are constantly improving the charging curve for both AC and DC charging, making both methods more efficient and convenient for EV drivers.

DC charging curve

DC charging, in contrast, can deliver much higher power to an EV by bypassing its slower onboard converter. However, this results in a decreasing charging curve as the EV’s battery initially accepts a high flow of power but gradually takes in less as it approaches full capacity. To better understand this concept, imagine a glass as the EV’s battery, a water bottle as a DC charging station, and the water inside the bottle as the power. Initially, you can quickly fill the glass with water, but as you approach the top, you need to slow down to prevent overflow.

You can take a look at our ABB Terra 54 DC Fast Charger.

This same logic applies to DC fast and ultra-fast charging, resulting in decreasing power output as the battery approaches full capacity. In fact, EVs require less power as the battery reaches around 80 percent full, which explains the decreasing power output seen in the charging curve.

Optimized by Optimole