Pushing the Limits Again: YMIN LKC Series -65℃ High-Voltage Aluminum Electrolytic Capacitors Define a New Era in Low-Temperature Performance for High-Voltage Aluminum Electrolytic Capacitors

I. The Challenge of Power Supply in Extreme Environments

In military equipment (such as field communications and radar systems), rail power supplies (auxiliary power supplies for trains in high-altitude and cold regions), and charging piles in northern winters and power supplies exported to Russia and North America, equipment often needs to start up instantly and operate stably at temperatures of -40℃ or even lower. High-voltage aluminum electrolytic capacitors, as key energy storage components in power modules, directly determine whether the entire system can power on normally due to their low-temperature performance.

When the ambient temperature drops below -55℃, the viscosity of the electrolyte in traditional high-voltage aluminum electrolytic capacitors increases dramatically, and the ionic conductivity drops drastically, causing the ESR (Equivalent Series Resistance) to soar and the capacitance to shrink significantly (to only 35% of the initial capacity). The engineering consequence of this physical phenomenon is that the power module cannot provide sufficient instantaneous energy at startup, resulting in either delayed startup or complete shutdown.

II. Why is Low Temperature a Natural Bottleneck for High-Voltage Capacitors?

The energy storage of aluminum electrolytic capacitors relies on ion migration in the electrolyte. At room temperature, the electrolyte has good fluidity, and ions can respond quickly to changes in the electric field. However, at low temperatures, the electrolyte viscosity increases, and it may even partially freeze, hindering ion movement. This manifests as:

Capacitance decreases: the usable charge decreases, and the actual capacitance value is far lower than the nominal value;

ESR increases: internal resistance increases, and ripple current generates a higher temperature rise, further deteriorating performance.

This causal chain means that under extremely cold conditions, the actual usable capacitance of the capacitor is the key indicator determining whether the equipment can function properly.

III. YMIN LKC Series: Breaking the -65℃ Low Temperature Limit

Addressing the above pain points, YMIN Electronics launched the low-temperature resistant LKC series 450V 150μF liquid leaded aluminum electrolytic capacitor. Through a unique electrolyte formula and structural optimization, this series extends the operating temperature range from -55℃ to +105℃ to -65℃ to +105℃, and achieves extremely low capacitance decay even under the harsh condition of -65℃.

Note: The above data are from YMIN Laboratory’s actual measurements (average of 2 samples). The average capacitance decay at -55℃ is approximately -8.78, and at -65℃, it is approximately -15.96.

IV. Material and Process Breakthroughs
This low-temperature performance is achieved through two core technologies:
Exclusive Low-Temperature High-Voltage Electrolyte Formula:** Maintains high ionic conductivity even at -65℃, preventing electrolyte freezing and solving the low-temperature capacity decay problem at the material level.
Optimized Internal Structural Design:** Ensures stable contact between the electrode foil and the electrolyte at extreme temperatures, maintaining consistent capacitor performance.

The resulting customer value is: In extremely cold environments like -65℃, the equipment can still achieve near-room-temperature energy storage support, significantly reducing the low-temperature start-up failure rate and improving system reliability (i.e., achieving highly reliable capacitance decay control).

V. Typical Application Scenarios and Recommended Specifications

【Recommended Specifications】

VI. Frequently Asked Questions (Q&A)

Q1: Our equipment needs to operate in an environment of -55℃ (such as military communications and high-altitude rail power supplies). Can commonly available aluminum electrolytic capacitors meet this requirement?

A: Most high-voltage aluminum electrolytic capacitors on the market have a low-temperature limit of -25℃ or -40℃, but at -55℃, their capacitance decays severely (generally exceeding 60%), and their ESR increases significantly, easily leading to cold start failures. YMIN’s previously launched LKC series can stably support operation at -55℃, with a measured capacitance decay of approximately -8.78%, while the industry average is above -50%. The latest upgraded LKC series further extends the operating temperature limit to -65℃, with an average capacitance decay of only -15.96% in actual tests at -65℃, making it an option for you.

Q2: Our next-generation products will challenge extremely cold environments of -65℃ or even -65℃. Are there any readily available high-voltage aluminum electrolytic capacitors on the market that can be used?

A: Currently, there are almost no standard products on the market that can support operation at -65℃. Most brands still operate at the -40℃ level, and their actual capacitance degradation performance at -40℃ varies considerably. YMIN’s LKC series is the first to achieve a wide operating temperature range of -65℃ to +105℃. Through its exclusive low-temperature, high-voltage electrolyte formula, it maintains high ionic conductivity at -65℃, keeping capacitance degradation within an acceptable range. This is currently one of the few proven -65℃-level high-voltage aluminum electrolytic capacitor solutions.

Q3: If my application scenario is an outdoor charging station in northern winters (around -40℃), is it necessary to find a capacitor with a -65℃ rating?

A: From an engineering redundancy perspective, it is absolutely necessary. Capacitors nominally rated for -55℃ are already close to their performance limits at -40℃, with significant capacitance degradation and increased ESR, leading to decreased long-term reliability. YMIN’s LKC series, however, has ample margin at -40℃, with capacitance loss far lower than ordinary capacitors, ensuring stable output from the charging station’s bus capacitors in frigid weather and preventing charging interruptions or efficiency degradation. Covering applications at -40℃ with a -65℃ capacity is an effective strategy for improving system reliability.

Q4: To ensure our power supply products can operate normally at -65℃, we currently use a full thin-film solution, which is bulky and costly. Are there any liquid aluminum electrolytic capacitors that can replace film capacitors?

A: YMIN LKC series capacitors have a capacitance decay rate of only -15% at ultra-low temperatures of -65℃, which meets the requirements. Due to the inherent advantages of liquid capacitors, their capacitance density is much higher than that of film capacitors, achieving a 1-for-4 substitution.

VII. Conclusion and Action Guidelines
For high-voltage power supply equipment that needs to operate stably in extremely cold environments such as -55℃ or even -65℃, YMIN LKC series capacitors provide a verified capacitor selection solution. Their capacitance decay control capability and wide operating temperature range can help engineers solve engineering problems such as low-temperature start-up failures and power instability.

For further information: To request a datasheet or samples, please visit the YMIN Electronics website (www.ymin.com) and obtain detailed test reports (low-temperature test data). For capacitor applications, contact YMIN.

[Abstract]
“Applicable Scenarios”: “Military equipment (field communication/radar), rail power supplies (auxiliary power supplies for high-altitude and cold-weather trains), DC charging piles (bus capacitors for northern winters), power supply products for export to extremely cold regions.”

“Core Advantages”: “Operating temperature -65℃~+105℃; low capacitance decay at -65℃; exclusive low-temperature electrolyte formula for high-reliability capacitance decay control.”

“Recommended Models”: “YMIN LKC 450V 150μF 18×40, LKC 450V 220μF 18×50, LKC 500V 100μF 18*35.”

“Action Guidelines”: “Obtain datasheets, request samples, contact technical support, and obtain -65℃/-65℃ test reports.”