Key elements to ensure safe charging of electric vehicles

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Key elements to ensure safe charging of electric vehicles

Posted Date: 2024-02-01

With the rapid development of electric vehicles, how to charge the batteries of electric vehicles safely, stably and quickly has become one of the key factors for whether electric vehicles can be widely accepted by consumers. Among them, important components to ensure the safety of battery charging are convenient It is a fuse that meets the specifications of the automotive industry AEC-Q200. This article will introduce you to the key technologies of electric vehicle charging, as well as the characteristics of fuses launched by SCHURTER that meet the requirements of the AEC-Q200 specification.

It is very important to ensure the safety of a large number of series and parallel rechargeable batteries

The supply of fossil fuels is limited, and harmful gases are released when burned, causing air pollution. This makes electric vehicles an important direction for the future development of the current automobile industry. But in recent decades, the number and size of cars has increased, making them more comfortable, stronger, safer, and therefore heavier, with mid-range cars already weighing 1.5 tons. Therefore, electric vehicles also require a large amount of energy to provide sufficient power.

Sufficient power for an electric car is achieved by interconnecting small battery cells (each cell size is 4 VDC/3200 mAh) in parallel and series, which requires 100 cells in series to obtain approximately 400 VDC operating voltage, and then through many of these 400 V series-parallel battery packs to achieve the durability, range and performance of the entire battery package. In a powerful electric vehicle, thousands of cells will be needed to be assembled quickly in this way.

Therefore, ensuring safe charging of electric vehicles is crucial, which involves multiple safety measures and practices. During the charging process, approved charging equipment must be used, and the charging equipment must be inspected and maintained regularly to avoid moisture and extreme environments. It is also necessary to insert and disconnect the plug correctly during the charging process, monitor the charging process, and follow the manufacturer's instructions. It is recommended to prevent overcharging and avoid physical damage. In electric vehicles, a battery management system (Battery Management System, BMS) is usually used to ensure the safety of charging and discharging.

The BMS of electric vehicles is a key electronic system used to monitor, control and manage the high-voltage lithium-ion batteries in electric vehicles. BMS is designed to maximize battery performance, safety and longevity. The functions of BMS usually include voltage monitoring, temperature monitoring, charge and discharge management, fault detection and management, capacity estimation, communication and control and other functions. BMS can maximize battery performance while also ensuring battery safety and long-term service life. Vehicles can use battery energy more efficiently while reducing the risk of battery damage or performance degradation.

Battery balancing is a key technology to ensure the safety of the charging process

The charging process is very important, considering that thousands of these batteries are installed in electric vehicles, and the batteries must ultimately be charged in the shortest possible time. The solution to this tricky task is called "cell balancing," which refers to the fact that multiple similarly constructed battery cells may have small differences in electrical characteristics due to manufacturing differences or usage conditions, causing some cells to be Other cells charge or discharge faster, causing the voltage or capacity of the cells to become unbalanced. "Battery balancing" is the electronic circuit (usually part of the BMS) that evenly charges the battery pack.

The main purpose of battery balancing technology is to ensure that each unit in the entire battery pack can be charged and discharged evenly to avoid problems caused by imbalance between units, such as capacity imbalance, voltage imbalance, etc. Battery balancing works by slowing down the charging of batteries that absorb energy very quickly, so the weakest link in a series battery pack determines the speed of the charging process. Each battery cell needs to be treated individually, which is the only way to utilize the maximum capacitance of the battery pack and offset the aging/degeneration of individual cells.

Of course, each individual cell in the battery pack must be protected against overcurrent. Thousands of fuses are required per battery pack, depending on each battery pack. Since there is no room for error in a battery pack, the requirement for such a fuse is complete reliability. Such protection must be able to operate without any failure for at least 15 years. The fuse must perform its function in the coldest winter as well as in the hottest weather, facing shock, vibration and daily wear and tear, as well as opening, closing, acceleration and other cycles. Capacity will be indispensable, and the requirements for these fuses are quite stringent.

Cell balancing technology is important to extend battery life, improve performance, and ensure safety. By maintaining a balance between individual battery cells, the performance of the entire battery pack is utilized more efficiently and the risk of possible battery damage or performance degradation is reduced.

AEC-Q200 specifies standard requirements for passive components in the automotive industry

AEC is the abbreviation of Automotive Electronics Council, behind which is a US-based organization focused on the standardization of electronic component qualifications in the automotive supply industry. The Q200 standard was launched in the mid-1990s and describes the requirements for passive components, while the Q100 standard and its derivatives focus on active components. These AEC standards are globally recognized and accepted by all leading manufacturers in the automotive industry.

The development of the AEC-Q200 standard aims to ensure the reliability and durability of automotive electronic components under extreme environmental conditions, because the internal environment of the car has very stringent requirements for electronic components, such as high temperature, low temperature, vibration, humidity changes, etc.

The AEC-Q200 standard was first introduced in 2001 and has been continuously revised and updated since then to adapt to changing technologies and needs. It covers a variety of test conditions and requirements to ensure the reliability of electronic components. The standard specifies various test items, including high temperature life test, low temperature life test, damp heat life test, damp heat cycle test, damp heat constant pressure test, temperature cycle test, mechanical vibration test, etc., to verify the reliability of components under extreme conditions. and durability.

Compliance with the AEC-Q200 standard is critical for parts manufacturers and suppliers in the automotive electronics supply chain. Parts that meet this standard can prove that they can provide stable and reliable performance in automotive applications and help reduce Automotive recalls and issues caused by electronic component failures while enhancing vehicle safety and reliability.

Specific tests and a specifically defined set of requirements for fuses used in automobiles have not been relevant throughout the history of automobiles. However, because technology and applications in the field of automotive electronics continue to evolve, with the introduction of electronic control units and electric drives, this situation has completely changed, and fuses will also be included as a subject in the next update of the Q200 standard, AEC-Q200 Standards are also constantly being updated and improved to ensure that they meet current and future automotive electronic component needs and to continue to improve the reliability and safety of automotive systems.

High-quality fuses that meet AEC-Q200 specifications

SCHURTER has always focused on the high reliability requirements of the aerospace industry, and cooperates with the European Space Agency (ESA) and develops products based on the specification requirements of other passive components of AEC-Q200. Through global cooperation with the automotive industry In close cooperation with the key players, SCHURTER has developed test procedures for fuses to meet the requirements of Q200. Fuses manufactured in this way can carry the unrestricted and internationally recognized Q200 "Approval Seal".

SCHURTER offers the automotive industry a complete range of AEC-Q200 compliant fuses supporting a variety of applications (battery management, air conditioning, close-coupled electronics for diesel and gasoline engines, etc.). SCHURTER's close links with international automotive organizations and the industry itself make SCHURTER well-equipped to solve all problems related to the protection of electronic equipment in vehicle manufacturing.

SCHURTER has always been a progressive innovator and manufacturer of electronic and electrical components worldwide. SCHURTER's products ensure a safe and clean power supply while making equipment easy to use. SCHURTER offers a wide range of standard products, including circuit protection, connectors, EMC products, switches and input systems, as well as electronic manufacturing services. In addition, SCHURTER is ready to work with customers to meet their application-specific requirements.

Take the SCHURTER UMT 250 series fuse as an example. This is a surface mount (SMD) fuse with a size of only 3 x 10.1 mm. It supports 250 VAC and 125 VDC. It is an SMD fuse that can operate from 80 mA to 10 A. , can be designed with the smallest compact package, achieve maximum breaking capacity with the smallest footprint, and is suitable for pulse-type continuous current.

The UMT 250 series operates in high current ranges from 80 mA to 10 A, supports high breaking capabilities of 200 A @ 250 VAC (IEC), and is UL listed for 277 VAC and 250 VDC and can be used in accordance with ATEx and IECEx requirements The impermeable hermetic sealing potting compound can also be used in intrinsically safe applications, including primary protection of SMD PCB, medical equipment, battery protection and other application fields.


The safety of battery charging and discharging of electric vehicles is a key element that cannot be ignored. Fuses that meet the AEC-Q200 standard are important components to ensure the safety of battery charging of electric vehicles. SCHURTER provides the automotive industry with a full range of fuses that comply with AEC-Q200 standards, which can meet the safety needs of various applications in electric vehicles and will be your ideal component choice for developing related products.

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