What is the relationship between capacitors and ADAS?

Capacitance Effects of MLCC and Tantalum Polymer Technologies

Over the past few years, the smallest size of the Tantalum Polymer Automotive portfolio has been 3528-21, and now, there are ultra-small case sizes 3216-12 (aka 1206) and 2012-10 (aka 0805). Kemet's T597 series uses the ultra-small 3216-12 case size and is already 125°C and fully qualified to AEC-Q200 standards.

The T597 series launched this year

In addition to AEC-Q200 requirements, the T597 series was also tested in flex (5mm, 60 seconds) and showed all electrical characteristics to be within specification with no cracks.

T597 EIA 3216-12 Flexible Board Test

The new tantalum polymer SMD T597's new case size provides a solution to space issues in order to meet the miniaturization trend of ADAS in the automotive market. For example, as a 5V output power rail for front and rear cameras, it saves board space for ultra-miniaturized ADAS applications.

In this type of application, 0805 and 1206 MLCCs with 10μF and 22μF are common, with maximum operating temperature limited to 105°C. In automotive-grade solutions, the highest capacitance tantalum polymer SMDs P2012-10 (same as 0805) and S3216-10 (same as 1206) may be considered as alternatives.

Wilmer Companioni points out that when replacing MLCCs with tantalum polymer capacitors, the total cost of the solution is the primary driver, not the cost of each component.

Supercapacitors help the future of automotive electrification

Since April 2019, my country has required buses over 9 meters to be equipped with AEB (automatic emergency braking) devices. Because AEB is a basic function of ADAS, some people say that the domestic ADAS system has ushered in policy dividends.

ADAS uses a variety of advanced sensors, controllers, actuators and other devices, all of which require a reliable and stable distributed multi-power network to provide energy in order to realize an integrated system that integrates environmental perception, planning and decision-making, multi-level assisted driving and other functions; at the same time, as a unified safety requirement for automotive electrical and electronic systems, the new version of the functional safety standard ISO26262-18 will also be gradually implemented, and the power safety of its actuators has become one of the key elements of the power supply system.

With the deployment of ADAS, higher requirements are placed on the power consumption of the entire vehicle. Lithium batteries, which are already heavy and have a limited range, are no longer sufficient. How to solve the problem of insufficient power?

As an energy storage device, supercapacitors have the characteristics of high power density, fast charge and discharge, wide operating temperature range, maintenance-free, green and environmentally friendly, high reliability and ultra-long life. Its ideal application is where high power and constant cycle are required, such as KERS (Kinetic Energy Recovery System), where braking energy can be stored and re-powered for on-board equipment.

As technology advances, batteries and supercapacitors have become complementary technologies: batteries provide long-term energy, while supercapacitors provide fast response and high power. Therefore, supercapacitors plus batteries are the future of automotive electrification.

The energy of the battery complements the high current and fast discharge of the supercapacitor

Ulrik Grape, CEO of NAWA Technologies, said his company spent 15 years developing a new type of supercapacitor that can provide three to five times the power and energy of existing supercapacitors. This ultra-fast carbon battery fills the gap between existing supercapacitors and lithium batteries. Its supercapacitor-type battery can more than double the range of electric vehicles, allowing them to travel 1,000 kilometers on a single charge, and can also be charged to 80% of capacity in 5 minutes.

He also admitted that even the most innovative supercapacitors cannot compete with lithium-ion batteries in terms of energy storage. He said: "Of course you can use supercapacitors to power a small car, but the range is short and you need to charge it frequently. For the entire automotive industry, hybrid batteries can unlock the full potential of our technology."

Talking about the original intention of developing hybrid batteries, Ulrik Grape said: "There is no doubt that automotive battery systems are improving significantly, but if two different technologies are combined, it can bring the best hybrid energy storage and power." The theory behind the hybrid battery is the combination of lithium-ion batteries and supercapacitors, which can significantly reduce the weight of the battery pack and improve the overall efficiency and system life.

NAWA's supercapacitors' metal plates are made using a VACNT (vertically aligned carbon nanotube) process, known as ultra-fast carbon batteries. These tubes are arranged in an array like bristles on a brush, greatly increasing the surface area available to hold an electrical charge.

The inner workings of an ultrafast carbon battery

Ulrik Grape also said: "By combining supercapacitors with lithium batteries, the lithium batteries can be made smaller, the complexity of the energy and thermal management systems can be reduced, and the total weight can be reduced from 300 kg to 210 kg with the same total power. The weight is reduced by 30%, but the performance is higher and the driving range is longer."

In fact, China is not lagging behind in the application of supercapacitors. As the first company to apply supercapacitors to passenger cars, Enjing Carbon Energy's full range of 3V supercapacitor monomers fully meet the AEC-Q200 automotive grade requirements and ISO16750-3 Table12 requirements. More than 100,000 units have been installed in models such as Hongqi H5/H9 and Volvo-XC40, and there are nearly ten projects designated, among which the users include many well-known European car brands.

People related to Enjing Carbon Energy believe that the functional safety analysis of automobiles shows that in the L2.5 level and above autonomous driving mode (Hands Off) state, a failure in the vehicle power supply will cause the vehicle driving safety load and autonomous driving load to fail to work. In order to remind the driver to take over the driving immediately and ensure driving safety during the takeover, a backup power supply is needed to power these loads to ensure driving safety. This is where supercapacitors come in handy.

Application of supercapacitor topology

After years of exploration, Enjing Carbon has successfully mastered the combination technology of dry electrodes and supercapacitors, and has more than 40 related patents, becoming one of the few companies in the world with the technical capability to provide 3V systems.

In the "dry electrode battery + supercapacitor" technology system, the dry electrode battery is like a long-distance runner with great endurance, providing a continuous source of power; the supercapacitor is like a 100-meter runner with amazing explosive power, providing the car with strong energy needed instantly, without chemical reactions, and can be charged and discharged millions of times without affecting its service life. In addition, Enjing Carbon Energy is also developing another new type of dry electrode battery, which is estimated to have an energy density 50% higher than the power battery on the market and a cost reduction of 30%.

Supercapacitor monomer

In addition, with the development of the "four modernizations" of automobiles, the number of on-board controllers and actuators is increasing. When a fault occurs, the redundant power supply quickly supplies power, making the vehicle fail-safe or fail-operable. Supercapacitors are the best choice for redundant power supplies because of their fast response, instantaneous power supply, long life, wide operating temperature range, safety and reliability, small size and high power.

The next blue ocean market

ADAS is considered as a prerequisite for achieving ADS (autonomous driving). Although it will take some time to fully realize the autonomous driving of cars, the market demand for ADAS continues to grow. It is estimated that by 2025, the global ADAS market will reach 27.5 billion euros. ADAS, which helps cars drive safely, is becoming a point of excitement for mass consumption.

In recent years, MLCC manufacturers that have encountered a profit "red ocean" in the consumer market have turned to the automotive market. However, compared with the general market, the automotive market has strict reliability requirements and the performance requirements for MLCC are also very different, so innovation is necessary.

Supercapacitors are still a blue ocean market in ADAS and other automotive fields. Of course, opportunities always come to those who are prepared. Let's see who has the ability!