The charger for new energy electric vehicles (EVs) is a crucial electric power conversion device designed specifically to charge the vehicle’s power battery. According to their installation location and functionality, chargers are mainly divided into on-board chargers and off-board chargers. This article explains the key differences between the two types from multiple perspectives.

1. Installation Location

• On-Board Charger:
  Installed inside the electric vehicle itself. Due to space and weight limitations of the vehicle, on-board chargers are generally compact, lightweight, and have relatively low power.

• Off-Board Charger:
  Installed externally, outside the vehicle, typically in charging stations. Without vehicle size constraints, off-board chargers tend to be larger in volume and higher in power capacity.

2. Power Supply and Charging Mode

• ● On-Board Charger:
  Connects to an AC power source (single-phase 220V or three-phase 380V) via a plug and cable. It converts AC power into DC power suitable for charging the vehicle’s battery.

• ■ Also called AC charger or slow charger.

• ■ Advantages: Convenient charging wherever an AC power socket is available, helping extend battery life due to slow, controlled charging.

• ■ Disadvantages: Limited by vehicle space, generally low power output, resulting in slow charging and longer charge times.

• ● Off-Board Charger:
  Connects directly to the AC power grid and converts AC to controllable DC power to charge the battery, commonly installed in DC charging piles.

• ■ Known as DC charger or fast charger.

• ■ Advantages: High power, can deliver large current for fast charging, significantly reducing charging time.

• ■ Disadvantages: Large size and weight, high construction costs, immobility, fewer available charging stations, and frequent fast charging may reduce battery lifespan.

• ■ Recommendation: Use slow charging as the primary method and fast charging as a supplement.

3. Structural Components

• ● On-Board Charger:
  Comprises two main parts:

• ■ Power Circuit: Includes AC voltage regulator, transformer, and power transistors to convert AC to DC power.

• ■ Control Circuit: Communicates with the Battery Management System (BMS) to dynamically adjust voltage and current and control the charging process.

• ● Off-Board Charger:
  Includes several modules such as power unit, control unit, metering unit, charging interface, power supply interface, and human-machine interface, designed for robust power conversion and user interaction.

4. Performance and Applications

On-board chargers offer high efficiency, reliability, safety, and ease of installation due to their compact design, with output power ranging from 2 kW to 40 kW. They meet the charging requirements for a wide range of vehicles including passenger cars, commercial vehicles, engineering machinery, special vehicles, and even shipborne applications.

5. About TC Charger – Leading EV On-Board Charger Manufacturer

TC Charger, based in China, has over 23 years of expertise in EV on-board charger development and manufacturing. Their factory spans over 2100 square meters with a standardized large-scale production line. Holding 2 technology invention patents and 16 utility model patents, TC Charger produces up to 60,000 units monthly. Their chargers are internationally certified, offering eco-friendly, high-efficiency solutions trusted by customers worldwide.

Summary