Preface

Aluminum electrolytic capacitors are core energy storage components in electronic circuits, widely used in consumer electronics, automotive electronics, industrial control, and other fields. They play a central role in critical functions such as power supply filtering, energy buffering, and signal coupling. As fundamental components requiring careful consideration in engineering design, their structural characteristics, process requirements, and lifespan properties directly impact the overall reliability of the equipment.

Follon Electronics will provide an in-depth technical analysis of aluminum electrolytic capacitors and introduce product solutions adapted to different application scenarios.

I. Basic Structure of Aluminum Electrolytic Capacitors

An aluminum electrolytic capacitor is formed by riveting positive and negative aluminum foils to positive and negative terminals, then winding them together with separator paper into a core, impregnating it with electrolyte, and finally sealing it with an aluminum case. The coordinated operation of these components enables the capacitor's charge storage and release functions.

With its unique structural design, aluminum electrolytic capacitors achieve extremely high capacitance density within a limited volume. This advantage makes them key components in power supply circuits and industrial control fields. Continuous advancements in material science and manufacturing processes have led to ongoing breakthroughs in efficiency, reliability, and miniaturization, providing solid technical support for the upgrading of modern electronic devices.

II. Soldering Conditions

In production, soldering of aluminum electrolytic capacitors should use temperature-controlled, uniformly heated infrared radiation (IR) or hot air reflow soldering, and vapor phase reflow soldering should be avoided. This is to prevent damage to the capacitor's internal structure from excessive peak temperatures during vapor phase heating. It is also necessary to strictly limit reflow soldering cycles to no more than two times, ensuring sufficient cooling time for the product between the first and second cycles.

Soldering Key Points

▲ Reflow Soldering Profile

1. Temperature rise: Average maximum of 3°C per second.

2. Temperature drop: Average maximum of 6°C per second.

3. Time from 25°C to peak temperature: Maximum 6 minutes.

   ① Preheating time from 150°C to 180°C should be within 120 seconds.

   ② Soldering time where the capacitor top temperature exceeds 217°C must not exceed tL (seconds).

   ③ The peak temperature at the capacitor top must not exceed Tp (°C), and the actual time within a 5°C range of the peak temperature must not exceed tp (seconds).

   ▲ Temperature and Time Classification (Swipe left to view the complete table)

III. Aluminum Electrolytic Capacitor Lifespan Calculation

The lifespan of an aluminum electrolytic capacitor primarily depends on its applicable environmental conditions (such as ambient temperature, humidity, etc.) and electrical load conditions (such as operating voltage, ripple current, etc.). Generally, the failure mechanism of aluminum electrolytic capacitors is considered to be the gradual evaporation of electrolyte through the rubber seal. Therefore, temperature factors (ambient temperature and internal heat caused by ripple current) have the greatest impact on capacitor lifespan, which can usually be estimated using the following formula:

Le = Lo ⋅ Kt ⋅ Kr

Where:

Le = Expected lifespan at operating temperature Te (h)

Lo = Lifespan at operating temperature To (h)

Kt = Ambient temperature influence factor

Kr = Ripple current influence factor

Kt = Lo ⋅ A^( (To - Te) / 10 )

Where:

To = Maximum rated operating temperature (°C)

Te = Actual ambient operating temperature (°C)

A = Acceleration coefficient (A ≈ 2 for the range from 35°C to the maximum operating temperature)

Kr = 2^( -ΔT / 5 )

Where:

ΔT = Internal core temperature rise due to ripple current (ΔT = Core temperature - Ambient temperature)

ΔT can be estimated using the following formula:

ΔT = (I² ⋅ R) / (β ⋅ S)

Where:

I = Ripple current through the capacitor (A rms)

R = Equivalent Series Resistance (ESR) of the capacitor (Ω)

β = Thermal radiation coefficient of the aluminum case (W/°C⋅cm²)

S = Surface area of the capacitor

When the influence of ripple current is neglected, the expected lifespan of the capacitor at lower temperatures can be referred to in the following chart.

▲ Quick Reference Chart for Expected Lifespan (Swipe left to view the complete table)

Example: For a product rated at 105°C, 2000 hours, if used continuously in a 60°C environment, its expected lifespan is approximately 5 years.

IV. Follon's Main Product Lines

As a professional manufacturer of aluminum electrolytic capacitors achieving full spectrum coverage, Follon Electronics, with its complete product portfolio and continuous technological innovation, has built a product matrix capable of meeting diversified and multi-level application needs.

Surface Mount (SMD) Aluminum Electrolytic Capacitors

SMD Aluminum Electrolytic Capacitors include:

• Standard Type: FVH series;

• High-Reliability Types: FVA (High-Temperature Long Life), FVT (High-Temperature Long Life), FVX (Ultra-High Temperature) series;

• Miniaturized Type: FVM (Reduced Size) series;

• Low-ESR Long-Life Types: FVR (Ultra-Low ESR), FFT (High-Capacitance Ultra-Low ESR), FVL (Long-Life Ultra-Low ESR), FVD (5000-hour High-Voltage Long Life), FVG (Ultra-Long Life), FVW (Ultra-Long Life Ultra-Low ESR), FVK (Ultra-Long Life) series;

• Non-Polarized Types: FVN (Non-Polarized Long Life), FNP (High-Temperature Non-Polarized) series;

• Low Leakage Current Type: FVC (Low Leakage Current).

Solid Aluminum Electrolytic Capacitors

Solid Aluminum Electrolytic Capacitors include:

• SMD Types: FPA (Standard) series, FPS (Reduced Size) series, FPK (Long Life) series, FPU (High Temperature) series;

• Through-Hole Types: PRA (Standard) series, FRS (Reduced Size) series, FRK (Long Life) series, FRU (High Temperature) series.

Hybrid (Solid & Liquid) Aluminum Electrolytic Capacitors

Hybrid Aluminum Electrolytic Capacitors include:

• SMD Types: FBV (Long Life) series, FBW (High Temperature) series;

• Through-Hole Types: FBR (Long Life) series, FBU (High Temperature) series.

▲ Follon Aluminum Electrolytic Capacitors - Product System Diagram (Swipe left to view the complete table)

In the ongoing wave of electronic technology iteration, Follon Electronics consistently adheres to strict process standards and solid technical expertise to provide customers with various aluminum electrolytic capacitor products, ranging from consumer electronics to industrial control, and from general standards to special demanding scenarios. Follon Electronics is willing to collaborate deeply with engineers and numerous industry partners, injecting solid momentum into the high-quality development of China's electronics industry with high-reliability, high-performance aluminum electrolytic capacitor solutions.

Contact Us

Guangdong Follon Electronic Technology Co., Ltd.

Jiangxi Follon Electronic Technology Co., Ltd.

Address: Building 3, South District, Haishan Science Park, Hukou County, Jiujiang City, Jiangxi Province, China

www.follon.com

Professional Manufacturer of High-Quality SMD Electrolytic Capacitors