The number of electric vehicle units on the road surpassed 26 million in 2022, fueling demand for reliable ev charging stations. The UK saw a 37% increase in public charge points, with EV charger manufacturers like TPSON providing the advanced EV charging solutions needed.
The core function of an EV charging station is converting grid AC power to DC power for the battery. Slower electric car charging relies on the car’s internal EV Charger. For fast ev charging or rapid ev charging, the station performs this conversion externally, delivering power directly. This principle applies from large public infrastructure to portable ev chargers.
The Core Principle: AC vs. DC Power
Understanding how an EV charging station works begins with a fundamental concept: the difference between Alternating Current (AC) and Direct Current (DC). The electricity grid supplies AC power, but an electric vehicle battery can only store DC power. Every charging session, therefore, involves a critical power conversion. The location of this conversion—inside the car or inside the station—defines the charging speed and method.
What is AC (Alternating Current) Charging?
AC charging is the most common method for home and workplace charging. It uses the standard electricity supplied by the power grid. The current alternates its direction periodically, a format that is efficient for long-distance transmission. However, this power is not directly compatible with your car’s battery.
| Feature | North America (United States) | Europe (Most of Continent) |
|---|---|---|
| Voltage | 110-120 Volts | 220-240 Volts |
| Frequency | 60 Hertz | 50 Hertz |
The Role of the Onboard Charger
Every electric vehicle contains a built-in component called an onboard charger. This device acts as a gatekeeper and converter for all incoming AC power. Its sole job is to transform the grid’s AC electricity into the DC electricity the battery can accept. The process is straightforward:
- AC power flows from the wall outlet or charging station through the cable.
- The onboard charger receives the AC power and uses internal components, like diodes, to convert it to DC.
- The car’s Battery Management System (BMS) then manages the flow of this newly converted DC power into the battery pack.
Why It’s Slower
AC charging is inherently slower because the conversion process happens inside the vehicle. The size, weight, and cost of the onboard charger limit its power handling capacity. Most onboard chargers are rated between 7kW and 22kW. This internal bottleneck means that no matter how much power an AC station can supply, the charging speed is ultimately restricted by the car’s own hardware.
What is DC (Direct Current) Fast Charging?
DC fast charging provides a high-speed alternative for rapid top-ups, commonly found along highways and in public charging hubs. This method delivers power in a way that significantly reduces charging time, making long-distance EV travel practical.
Bypassing the Onboard Charger
The key to fast ev charging is its ability to bypass the car’s onboard charger entirely. Instead of sending AC power into the car for conversion, the DC charging station delivers DC power directly to the battery. This approach removes the bottleneck created by the vehicle’s internal hardware, allowing for a much higher rate of energy transfer. Advanced solution providers like TPSON engineer these powerful systems to manage this high-voltage delivery safely and efficiently.
How Stations Convert Power Externally
A DC fast charging station is a much larger and more complex piece of equipment because it houses a powerful AC-to-DC converter. This external converter takes high-voltage AC power from the grid and transforms it into high-voltage DC power before it ever enters the vehicle. This allows the station to deliver immense charging power directly to the battery. The typical power outputs for dc fast charging include:
- Rapid Chargers: 50 kW to 150 kW
- Ultra-Rapid Chargers: 150 kW up to 350 kW
This direct delivery of power is what enables dc fast charging to add hundreds of miles of range in under an hour.
Why Power Conversion is Essential for Batteries
Ultimately, all charging methods must accommodate a basic principle of battery chemistry. Batteries, by their very nature, store energy through a chemical reaction that requires a steady, one-way flow of electrons.
Electric vehicles, like other battery-powered devices such as phones and laptops, are designed to store power exclusively as Direct Current (DC). Consequently, any Alternating Current (AC) power must undergo conversion to DC before it can be used to charge the battery.
This non-negotiable requirement is why power conversion is the heart of EV charging. Whether it happens slowly inside the car or rapidly inside the station, turning AC into DC is the essential step that makes driving on electricity possible.
How Different Types of EV Charging Stations Work
The world of EV charging is categorized into different “levels,” which primarily define the charging speed and power output. Understanding these types of ev charging stations helps drivers choose the right option for their needs, whether they are at home or on the road. Each level works differently based on its power source and how it delivers energy to the electric vehicle.
Level 1 Chargers: Slow and Simple
Level 1 charging represents the most accessible and basic method for powering an electric vehicle. It requires no special installation and uses hardware that often comes standard with the vehicle purchase.
Using a Standard 120V Outlet
This method utilizes a standard 120-volt wall outlet, the same kind you use to plug in a lamp or a laptop. The charger itself is typically a portable cordset that connects the car directly to the household socket. Power flows from the grid as AC, which the car’s onboard charger then converts to DC. Its simplicity is its greatest strength.
Ideal for Overnight Charging
The convenience of level 1 charging comes at the cost of speed. It delivers power very slowly, typically adding just 3 to 5 miles of range per hour.
For an EV with an average 60 kWh battery, a full charge from a standard outlet could take anywhere from 8 to over 24 hours. This makes it best suited for plug-in hybrids with smaller batteries or for drivers who travel short distances daily and can leave their car plugged in overnight.
Level 2 Chargers: The Everyday Standard
Level 2 charging is the most common and practical solution for both home and public charging. It offers a significant speed boost over Level 1, making it the go-to for daily driving needs.
Using a 240V Circuit
A Level 2 station requires a 240-volt circuit, similar to what powers an electric stove or clothes dryer. This higher voltage allows the station to deliver more AC power to the car’s onboard charger. While public Level 2 chargers are widely available, installing one at home requires a professional electrician. Power outputs for level 2 charging vary by location:
- Residential Use: Typically 7.4 kW on a single-phase supply.
- Workplace/Public Use: Can deliver up to 22 kW on a three-phase supply.
Faster AC Power Delivery
With its increased power output, a Level 2 charger can replenish a battery much faster than Level 1. It typically adds around 25 miles of range for every hour it is connected, making it easy to get a full charge overnight or top up significantly during a workday. This balance of speed and cost is why advanced solutions from providers like TPSON are popular for residential and commercial installations.
Level 3 Chargers: DC Fast Charging
Often referred to as DC fast charging or rapid ev charging, Level 3 is the quickest way to power an EV. These powerful ev charging stations are the key to making long-distance travel practical and efficient.
High-Voltage Direct Power
Level 3 charging works by completely bypassing the car’s slower onboard charger. The station itself contains a massive AC-to-DC converter, allowing it to deliver high-voltage DC power directly to the battery. This direct connection enables extremely high rates of power transfer. The power outputs are impressive and continue to grow:
- Rapid Chargers: 50 kW to 150 kW
- Ultra-Rapid Chargers: 150 kW to over 400 kW
Designed for Rapid Top-Ups
The primary purpose of fast ev charging is to add significant range in a short amount of time, mimicking the experience of a gas station stop. Instead of charging to 100%, drivers typically use rapid ev charging to get to 80%, as the charging speed slows considerably after that point to protect the battery. The time savings are dramatic.
| Car Model | 50kW (20-80%) | 100kW (20-80%) |
|---|---|---|
| Mini Electric (28.9 kWh) | 21 mins | Not compatible |
| Nissan Leaf (37 kWh) | 27 mins | Not compatible |
| Tesla Model 3 (57.5 kWh) | 41 mins | 14 mins |
With ultra-rapid dc fast charging points, a usable top-up can take as little as 10 to 30 minutes, making road trips seamless.
Private EV Charging vs. Public EV Charging
An electric vehicle driver can charge their vehicle in two primary settings: at a private residence or at a public station. Each environment operates differently, offering distinct advantages in convenience, speed, and accessibility. Understanding the mechanics of both private and public EV charging helps drivers manage their power needs effectively.
How Private EV Charging Works at Home
Charging at home is the foundation of EV ownership for many drivers. It provides unparalleled convenience and cost-effectiveness, turning a garage or driveway into a personal refueling station. This method relies on the home’s existing electrical system.
The Convenience of Level 1 and 2
Private EV charging primarily uses Level 1 and Level 2 chargers. Level 1 offers plug-and-play simplicity with any standard wall socket, ideal for overnight top-ups. For faster and more practical daily use, Level 2 is the preferred choice for home EV charging. A Level 2 station significantly reduces charging time, making it easy to start each day with a full battery. The ability to manage charging at home ensures the vehicle is always ready for the daily commute.
Installation and Grid Connection
Installing a Level 2 charger for home EV charging requires professional expertise. A qualified electrician must assess the home’s electrical capacity to ensure it can handle the additional load.
Before installation, a technician will check the main fuse and determine if the electrical supply is shared with other properties. This assessment is crucial for safety and performance.
The process involves running a dedicated circuit from the main electrical panel to the charger’s location. In the UK, the total cost for a standard 7kW charger and its installation typically ranges from £800 to £1,500. This investment enhances the charging infrastructure of the home, providing a reliable power source for an electric vehicle.
How Public EV Charging Networks Operate
Public EV charging networks provide the essential infrastructure that supports long-distance travel and offers charging options for drivers without home access. These networks consist of strategically placed stations in locations like shopping centres, service stations, and dedicated hubs.
Accessing Level 2 and DC Fast Chargers
Public networks offer a mix of Level 2 and DC fast chargers. Level 2 stations are common in destinations where drivers park for several hours, such as workplaces or retail parks. For rapid refueling on long journeys, drivers depend on DC fast chargers located along major motorways. These powerful stations, engineered by advanced providers like TPSON, can add significant range in under 30 minutes.
Network Providers and Roaming
A variety of companies operate the public EV charging infrastructure. To simplify the user experience, many of these providers have established roaming agreements.
- Roaming allows a driver to use chargers across different networks with a single app or RFID card.
- It eliminates the need to create multiple accounts, making the process more seamless.
- These agreements require collaboration between competing companies to improve driver convenience.
This interconnectivity is vital for creating a user-friendly ecosystem, ensuring drivers can easily find and use a compatible charger wherever they travel.
The Anatomy of an EV Charging Station
While they appear simple, EV charging stations are sophisticated devices with distinct external and internal components. These parts work together to deliver power safely and efficiently from the grid to an electric vehicle. Understanding this anatomy reveals the technology behind every charging session.
External Components You Interact With
The external parts of an ev charging station are designed for durability and user interaction. They must withstand public use and harsh weather while providing a clear, simple interface for drivers.
The Housing and User Interface
The housing is the protective shell of the station. Manufacturers build these enclosures from robust, weatherproof materials to ensure long-term durability in outdoor environments. Key material properties include:
- UV Resistance: The casing and wiring must resist degradation from prolonged sunlight exposure.
- Corrosion Resistance: Outdoor chargers use materials like powder-coated mild steel and specialist alloys, especially in humid regions where salt and moisture can cause damage.
The user interface typically includes a screen displaying instructions, charging status, and cost. It also features an RFID or credit card reader for payment authentication.
Charging Cables and Connectors
The charging cable and its connector are the physical link to the vehicle. While the cable is a heavy-duty, insulated wire, the connector type varies by region and charging standard. The three main standards for fast ev charging are NACS, CCS, and CHAdeMO.
| Feature | NACS (Tesla) | CCS (Combo) | CHAdeMO |
|---|---|---|---|
| Primary Region | North America (growing) | North America, Europe | Japan, older models |
| AC/DC Pins | Combined in one plug | Separate sections | Separate plug needed |
| Connector Size | Compact | Bulky | Bulky |
| Communication | Proprietary (opening up) | PLC (Power Line Comms) | CAN bus |
The North American Charging Standard (NACS) is compact and handles both AC and DC power. The Combined Charging System (CCS) is the dominant standard in Europe and is used by manufacturers like BMW and VW. CHAdeMO is an older standard found on vehicles like the Nissan Leaf, but it is becoming less common on new ev charging stations.
Internal Electronics That Manage Power
Inside the housing, a network of advanced electronics manages everything from safety protocols to network communication. These components are the brain of the operation.
The Power Control Unit
The Power Control Unit (PCU) acts as the central processor. It manages the flow of charging power, communicates with the vehicle’s Battery Management System (BMS), and monitors safety parameters like voltage and temperature. This unit ensures the station delivers electricity safely and effectively.
The Communication Module
This module connects the station to a central network management system (CSMS). It uses protocols like the Open Charge Point Protocol (OCPP) to act as a universal translator.
OCPP facilitates data exchange between the physical charge point and the software backbone of the charging network. The module handles user authentication, sends real-time charging data, and allows for remote diagnostics and management.
The AC/DC Converter (in DC Chargers)
This powerful component is exclusive to DC fast charging units. While Level 1 and 2 chargers supply AC power for the car to convert, a DC station converts high-voltage AC from the grid into DC internally. This external conversion, engineered by advanced providers like TPSON, allows the charger to bypass the car’s onboard limits and deliver immense power directly to the battery.
The “Handshake”: How the Car and Station Communicate
Before a single kilowatt of energy flows, an electric vehicle and a charging station engage in a crucial digital conversation. This “handshake” is a series of communication protocols that establishes a safe connection, agrees on a charging speed, and monitors the entire session. It ensures the charging process is both efficient and secure.
Initiating the Connection
The communication begins the moment a driver plugs the connector into the vehicle’s charge port. This physical link opens a dedicated line for the car and station to talk.
The Initial Plug-In Signal
The first signal is often a simple analog message known as the Control Pilot. This signal uses Pulse Width Modulation (PWM) to communicate the status of the connection. The station sends a voltage signal that tells the car it is present. The car then responds, confirming its presence and readiness. This initial dialogue moves through several states:
- State A: The cable is disconnected.
- State B: The vehicle is connected but not yet ready to receive power.
- State C: The vehicle is connected and has authorized charging to begin.
Exchanging Key Information
Once the basic connection is verified, the car and station exchange more detailed data to negotiate the terms of the charge. This negotiation ensures the session is optimized for both the vehicle’s battery and the station’s capacity.
Vehicle Battery Status
The electric vehicle’s Battery Management System (BMS) reports critical information to the station. This includes the battery’s current state of charge (SoC), its internal temperature, and the maximum charging power it can safely accept at that moment.
Station Power Capacity
In response, the charging station communicates its maximum power output. For more advanced communication, especially with DC fast chargers, they use digital protocols like ISO 15118. This standard enables smart charging features, enhanced data security through Transport Layer Security (TLS), and even bidirectional energy flow, where the vehicle could potentially send power back to the grid.
Safety and Monitoring Protocols
The handshake does not end once charging starts; it becomes a continuous monitoring loop. This constant communication is the core of the system’s safety features.
Real-Time Voltage and Temperature Checks
Throughout the session, the station and car constantly check voltage levels and battery temperature.
Advanced chargers from providers like TPSON incorporate thermal management systems. These systems monitor for excess heat and can automatically reduce charging power to prevent the battery from overheating, safeguarding both the car and the charger. Safety interlocks also ensure that power is cut immediately if the cable is disconnected prematurely, preventing any risk of electric shock.
Understanding the Charging Curve
This exchange of data allows the charger to follow the vehicle’s requested “charging curve.” The power delivery is not constant. It typically starts low, ramps up for the main phase of charging, and then gradually tapers off as the battery approaches 80-100% capacity. This controlled process protects the battery’s long-term health and longevity.
How to Use Public EV Charging Stations: A Step-by-Step Guide
Using public EV charging stations is a straightforward process. For new electric vehicle drivers, understanding the steps transforms a potentially confusing task into a simple routine. This guide on how to use public ev chargers breaks down the process from arrival to departure.
Step 1: Find and Connect
The first challenge is locating a suitable charger. Drivers must find a station that is both available and compatible with their vehicle’s needs.
Locating a Compatible Station
Drivers can use dedicated mobile applications to find nearby public charging stations. These apps provide real-time data on availability, charging speed, and connector types. Popular options in the UK include:
- Zapmap: Shows real-time availability and allows users to plan journeys with filters for specific charger types.
- bp pulse: Helps users find charge points across the UK, including thousands of rapid and ultra-fast options.
- Motability Go Charge: Provides access to over 50,000 public chargers from more than 20 network operators.
Matching the Connector to Your Car
After locating a station, the driver must ensure the connector matches their vehicle’s charge port. While most new cars use the CCS standard, some older models may require a CHAdeMO connector. The driver simply selects the correct cable from the station and plugs it securely into the car.
Step 2: Authenticate and Pay
Once connected, the driver needs to authorize the session and arrange payment. Public EV charging networks offer several methods for this.
Using a Mobile App
Many networks require drivers to use a specific mobile app. The driver selects the correct charger ID in the app, confirms their payment details, and initiates the session remotely. This method is common across many public EV charging providers.
Tapping an RFID Card or Credit Card
Alternatively, drivers can use an RFID card linked to their network account or a standard contactless payment method.
UK regulations now mandate that new public charging stations with a capacity of 8 kW or higher must offer contactless payment. This allows drivers to pay on a pay-as-you-go basis using a bank card, Apple Pay, or Google Wallet without needing a pre-existing account.
Step 3: Start and Monitor the Session
With payment authorized, the charging session begins. The driver should always confirm that power is flowing correctly.
Confirming Charging Has Begun
A driver can verify the session has started in a couple of ways. First, the mobile app will typically send a confirmation that charging is in progress. Second, the charger’s light indicator provides a visual cue; it often flashes green to show that the vehicle is actively charging.
Tracking Progress on Your App or Dash
Drivers can monitor the charging progress through the network’s mobile app or on the vehicle’s dashboard display. These interfaces show the current battery percentage, the power being delivered, and the estimated time remaining until the charge is complete.
Step 4: End the Session and Disconnect
The final part of using public ev charging stations involves safely ending the session and disconnecting the vehicle. Following the correct procedure ensures the safety of the driver, protects the equipment, and leaves the station ready for the next user. This last step is a crucial part of knowing how to use public ev chargers correctly.
Properly Stopping the Power Flow
A driver must always terminate the charging session electronically before physically removing the cable. This digital command cuts the power flow and releases the locking mechanism that holds the connector in place.
Always stop the charging session before attempting to unplug the charging cable from the car. Failure to do so may cause damage to the cable or the system.
The exact process can vary slightly between networks and vehicles, but it generally follows a clear sequence. To safely stop a DC fast charging session, a driver should:
- Ensure the vehicle is unlocked, as this often signals to the car that the session is about to end.
- Follow the on-screen instructions at the charger. This may involve selecting the connector on the screen and pressing a ‘stop’ button.
- Use the same authentication method to end the session as was used to start it. The driver might need to re-present their RFID card or contactless payment card to the terminal. Alternatively, they can use the stop button within the network’s mobile app.
Some vehicles offer additional ways to stop the charge. For example, certain Volvo models allow the driver to press a release button near the charge port or use the car’s center display to end the cycle. Advanced systems, like those engineered by TPSON, include safety interlocks that prevent power from flowing if the cable is disconnected prematurely, adding a layer of protection.
Unplugging and Stowing the Cable
Once the station and vehicle confirm the power flow has stopped, the connector unlocks. The driver can then unplug the cable from the vehicle. It is good practice to reattach any protective covers to both the car’s charge port and the connector itself. This action prevents dust, moisture, and debris from damaging the sensitive electronic contacts.
After disconnecting from the car, the driver should return the cable neatly to the station’s holster or designated hook. Leaving the cable on the ground creates a trip hazard and exposes it to potential damage from weather or other vehicles. Finally, drivers should move their car from the bay as soon as charging is complete. Many public charging stations charge idle fees to discourage drivers from occupying a spot after their session has ended, ensuring the charger remains available for others.
EV charging stations function as intelligent gateways, safely managing the flow of electricity to an electric vehicle. The fundamental difference in how each ev charging station works is the location of the AC-to-DC power conversion. This single factor determines the speed of all electric car charging.
The charging process relies on a system of communication, power conversion, and safety monitoring. This makes charging a simple and reliable experience, from a standard home unit to an ultra-rapid station.
Advanced solution providers like TPSON continue to innovate, making ev charging stations more efficient and accessible for every driver.
FAQ
Can I use any public charger for my EV?
Most new EVs use the CCS connector, which is widely available. Some older models might need a CHAdeMO connector. Drivers should always check station compatibility using a dedicated app before arriving to ensure the connector and power level match their vehicle’s needs.
Is rapid ev charging bad for my battery?
Occasional rapid ev charging is perfectly safe for modern electric vehicles. However, relying on it too frequently can accelerate battery degradation over time. Most drivers balance it with slower charging at home to maintain optimal long-term battery health and performance.
How much does it cost to install a home charger?
The total cost for a home ev charging installation depends on several factors. These include the charger model and the complexity of the required electrical work. A qualified electrician can provide an accurate quote after assessing the property’s existing electrical system.
What is the difference between kW and kWh?
These units measure different aspects of electricity.
- Kilowatt (kW): Measures power, which is the rate of energy flow. It defines the charging speed.
- Kilowatt-hour (kWh): Measures energy. It defines the amount of energy stored in a battery or delivered in a session.
Can I charge my EV in the rain?
Yes. EV charging stations and vehicle charge ports are engineered with robust, weatherproof seals and multiple safety interlocks. These design features make charging in wet conditions completely safe for both the user and the equipment, preventing any risk of electrical shock.
Why does charging slow down after 80%?
A vehicle’s Battery Management System (BMS) intentionally reduces the charging speed as the battery approaches full capacity. This process protects the battery cells from overheating and stress. This controlled “charging curve” is essential for preserving the battery’s long-term health and lifespan.
