Question Type: Design Support
Q: At -40°C, the peak starting current of the door lock motor may double. Can the supercapacitor still output sufficient instantaneous current when the ESR rises due to low temperature?
A: It can fully meet the requirements. We recommend using a 25F 2.7V supercapacitor. This specification has an ESR < 30mΩ at room temperature and an instantaneous discharge capacity of over 15A. Even at -40°C, where the discharge capacity decreases by 30%, it can still output a discharge capacity of over 10A, fully meeting the requirements for normal door lock motor drive and unlocking at low temperatures.
Question Type: Design Support
Q: How much energy is required for a single unlocking action? If 2-3 consecutive actions are required, is the supercapacitor capacity sufficient?
A: Taking a passenger car as an example, the door lock motor has an unlocking current of 3.5A and an unlocking time of 0.1S. The energy required to unlock two doors is as follows: 12V × 3.5A × 0.1S × 2 times = 8.4J. With 4 door handles + 4 door locks + 2 child locks, the total energy required is: (8.4J × 10 locks) / 80% (conversion efficiency is assumed to be 80%) = 105J. It is recommended to use 5 25F 2.7V supercapacitors connected in series, which can provide the following energy: 0.5 × 5F × (12V² – 9V²) = 157.5J. Even with a capacity decay of about 30%, it can still unlock normally more than twice.
Question Type: Design Support
Q: After the vehicle has been parked for 2 weeks, will the self-discharge of the supercapacitor cause it to fail to unlock in the event of a collision?
A: Supercapacitors utilize their fast-charging characteristics to fully charge in a very short time after the vehicle starts. For example, with a charging current of 5A, five 25F 2.7V supercapacitors connected in series can charge from 0V to 12V in just 20 seconds. There’s no need to worry about excessive self-discharge of the supercapacitors after the vehicle has been parked for a long time.
Question Type: Design Support
Q: After the vehicle is powered on, regulations require it to return to an “unlockable” state within xx seconds. Can the supercapacitors charge to the “unlockable” capacity within the specified time?
A: It fully meets the regulatory requirements. It can be fully charged in a very short time after the vehicle starts. For example, with a charging current of 5A, five 25F 2.7V supercapacitors connected in series can charge from 0V to 12V in just 20 seconds.
Question Type: Technical Principle
Q: If multiple supercapacitors are used in series, will there be issues with uneven voltage between individual cells? Will this affect the reliability of the operation during a collision?
A: Reliability is fully guaranteed. YMIN supercapacitors undergo 100% capacitance and resistance matching before leaving the factory, with capacitance and ESR tolerances controlled within 5%, ensuring consistency between individual cells. In practical applications, the circuit is equipped with a balancing circuit; when there is a deviation in the voltage of a single cell, the circuit will actively perform voltage balancing, thus providing double protection for product reliability.
Question Type: Design Support
Q: How to monitor the health status of supercapacitors in applications? What parameters need to be monitored?
A: In practical applications, because the charging and discharging characteristics of supercapacitors are almost completely linear, health status monitoring is relatively simple. It only requires discharging the capacitor through a load, taking the voltage difference within the corresponding discharge range, and performing logical calculations through software to monitor the product’s health status. The industry standard for judging lifespan is: capacitance decay within 30%, and internal resistance not exceeding 4 times; adjustments can also be made flexibly according to actual operating conditions.
Question Type: Technical Principle
Q: Under freezing, jamming, or object-clamping conditions, the instantaneous current of the motor can reach tens of amperes. Can supercapacitors withstand such pulses?
A: Absolutely. Taking a passenger car as an example, the locked-rotor current of a door lock is typically 7-8A, the locked-rotor current of a child lock is 2-3A, and the locked-rotor current of a door handle is around 10A. A 25F 2.7V supercapacitor can achieve an instantaneous discharge capacity of over 15A at room temperature. Even at -40℃, where the discharge capacity decreases by 30%, it can still output a discharge capacity of over 10A, which fully meets the usage conditions under locked-rotor conditions.
Question Type: Life Cycle Issue
Q: How can you ensure that the supercapacitor can meet the life cycle of the entire unit for more than 10 years? Are there any relevant data and lifespan calculation models?
A: YMIN SDH series supercapacitors belong to the 85℃ high-temperature resistant series. The products meet automotive-grade requirements. Based on a 10-year lifespan, using 5 capacitors in a 12V power supply system, operating for 3 hours daily at 45℃, the total operating time is approximately 11,000 hours. According to the supercapacitor lifespan calculation rule (a 10℃ decrease in temperature doubles the lifespan, a 0.1V decrease in voltage increases the lifespan by 1.5 times), therefore, under 45℃ and 2.5V (single capacitor voltage) conditions, the lifespan is 36,000 hours, far exceeding the product’s design lifespan and fully meeting the 10-year lifespan requirement.
Question Type: Technical Principle
Q: The mechanism of supercapacitor capacity decay and internal resistance increase, and the relationship between voltage and temperature.
A: The performance decay of supercapacitors is mainly related to two materials—the electrodes and the electrolyte. During long-term charge-discharge cycles, frequent insertion/extraction of ions into/out of the activated carbon pores can cause partial collapse or blockage of the microporous structure, preventing ion adsorption and thus reducing capacity and increasing internal resistance. Under the influence of voltage and temperature, the electrolyte decomposes and vaporizes, thereby reducing capacity and increasing internal resistance. Voltage is a key factor leading to performance degradation. The higher the operating voltage, the faster the electrolyte decomposes; lowering the voltage can extend lifespan. For every 0.1V decrease in voltage, lifespan increases by 1.5 times. High temperatures drastically accelerate electrolyte decomposition and electrode degradation. According to Arrhenius’s Law, for every 10°C increase in temperature, lifespan is halved. Operating at the lowest possible temperature can extend product lifespan.
Question Type: Technical Principle
Q: After the vehicle is powered off, will the supercapacitor discharge in reverse to other vehicle body modules? Is isolation required?
A: This can be resolved, and isolation is necessary. Unidirectional isolation using MOSFETs or Schottky diodes can prevent the supercapacitor from being “absorbed” by other modules. With isolation, the emergency unlocking action remains stable and will not be interfered with by the vehicle’s electrical grid.
Question Type: Design Support
Q: How safe is the supercapacitor? Do its raw materials contain hazardous substances? Are there any special requirements for transportation? A: Supercapacitors store energy through physical energy storage, without any chemical reactions. Therefore, the product has excellent safety performance. It leaves the factory uncharged, requires no transportation certification, and all materials used comply with RoHS and REACH certifications, making it a truly green energy product. It has significant advantages in environmental protection and safety, as all its components contain no harmful chemicals and will not pollute the environment.
Question Type: Design Support
Q: After a collision, if the main battery is instantly de-energized, will the electronic door locks fail to open? Will the doors become stuck, preventing escape? Is it necessary to rely on a supercapacitor to guarantee unlocking?
A: Don’t worry, it won’t. After a collision, when the main power supply is lost, the supercapacitor, acting as a backup power source for the door locks, will quickly and sequentially drive the door locks, child locks, and door handle motors, instantly unlocking the doors.
Question Type: Design Support
Q: If the collision is severe and the doors are deformed, will unlocking still be possible?
A: After a collision, the supercapacitor, utilizing its rapid response capability, will sequentially and quickly activate the door locks, child locks, and door handle motors within one second, ensuring immediate door unlocking.
Question Type: Performance Comparison
Q: In extremely low temperatures, can the supercapacitor still provide enough energy to unlock the doors?
A: Absolutely. Taking a 25F 2.7V supercapacitor as an example, this specification can achieve an instantaneous discharge capacity of over 15A at room temperature. Even at -40℃, where the discharge capacity decreases by 30%, it can still output a discharge capacity of over 10A, fully meeting the requirements for normal door lock motor activation and unlocking at low temperatures.
Question Type: Technical Principle
Q: How do the door locks unlock after a vehicle collision? Is manual operation required?
A: It’s fully automatic and requires no operation whatsoever. After a collision, the supercapacitor acts as a backup power source for the door locks. It fully charges in a very short time after the vehicle starts. Following the collision, the supercapacitor, utilizing its rapid response capability, sequentially and quickly activates the door locks, child locks, and door handle motors within one second, ensuring immediate door unlocking.
Question Type: Design Support
Q: How can I confirm that the supercapacitor backup power system is always in normal standby mode? How can I know if it malfunctions?
A: In practical applications, the collision module integrates a supercapacitor health monitoring function. This involves discharging the capacitor through a load, recording the voltage difference within the corresponding discharge range, and performing logical calculations through software to monitor the product’s health status in real time.
Question Type: Design Support
Q: If the vehicle has been parked for a long time and the capacitor is depleted, will the unlocking function still work normally?
A: Supercapacitors utilize their fast-charging capabilities to fully charge in a very short time after the vehicle starts. For example, a commonly used 25F 2.7V supercapacitor can be fully charged from 0V to 12V in just 20 seconds. There’s no need to worry about the supercapacitor running out of power after the vehicle has been parked for a long time.
Question Type: Life Cycle
Q: Does this capacitor require maintenance after being installed in the car?
A: No. Supercapacitors have a cycle life of over 500,000 charge-discharge cycles. Assuming a 10-year lifespan, the lifespan of a supercapacitor far exceeds the product’s design lifespan, truly achieving maintenance-free operation.
Question Type: Life Cycle
Q: Will the supercapacitor suddenly run out of power? Is it prone to aging? Will it fail at a critical moment (collision)?
A: No, the charging and discharging characteristics of supercapacitors are linear. Sudden power loss is unlikely. Even if completely depleted, it can be fully charged within seconds, without affecting normal use.
Question Type: Safety
Q: Will the supercapacitor explode or catch fire? Is a short circuit dangerous? Is it safe after a collision?
A: Supercapacitors use physical energy storage methods without any chemical reactions, making them extremely safe. They will not catch fire or explode upon impact, making them the best green and environmentally friendly backup power source.
Post time: Dec-29-2025