Aluminium Capacitors

Aluminium capacitors are a type of electrolytic capacitor. A capacitor is a two-terminal electrical component that can store energy, somewhat like a battery. Aluminium capacitors are polarised, meaning that the energy can only flow in a single direction. This makes them ideal for applications where high capacitance values are required, such as smoothing and filtering in power supplies, computer motherboards and domestic appliances.

High purity grade aluminium is used to create the anode and cathode foils. These then undergo electrolysis to form an extremely thin insulating layer of aluminium oxide, which acts as the dielectric of the capacitor. Capacitors are termed “wet” or “solid” depending on the electrolyte applied during this process. Liquid electrolytes create “wet” capacitors, while solid electrolytes (e.g. polymer or tantalum technologies) are “dry”.

Types of Aluminium Capacitors

Aluminium Electrolytic Capacitors

Aluminium electrolytic capacitors are the most common type of aluminium capacitor. They consist of a liquid or gel electrolyte which provides a high ionic concentration for efficient charge storage. The electric charge that can be stored by the capacitor is measured in farads but are usually in the range from nanofarads to millifarads. Aluminium capacitors offer high capacitance values to provide smoothing and filtering functions in the circuit and are particularly effective in reducing ripple voltage in DC power supplies. They also have reasonable Equivalent Series Resistance (ESR) but have the lowest leakage current from all capacitor types.

Polymer Electrolytic Capacitors

Polymer electrolytic capacitors, also known as polymer capacitors or polymer e-caps, utilise a conductive polymer as the electrolyte material within a layered aluminium design. This polymer electrolyte offers several advantages over traditional liquid electrolytes, including higher conductivity, a wider operating temperature range, and no risk of drying out. These capacitors are known for their very low Equivalent Series Resistance (ESR), which is a measure of the capacitor's internal resistance. Low ESR translates to better performance in high-frequency applications and improved ripple current handling capabilities, offering package options between 2.2 to 470 microfarad.

Hybrid Capacitors

Hybrid capacitors (sometimes termed polymer hybrid aluminium capacitors) combine the benefits of both wet and solid capacitors. They typically use a mixture of a liquid electrolyte and solid polymer, offering a balance of high capacitance, low ESR, and high tolerance for ripple current. The liquid electrolyte keeps the leakage current very low and also allows self-repairing of the aluminium foils which prevent a drop in capacitance. These capacitors are often used in applications where high reliability and endurance are required, such as automotive electronics and industrial equipment.

Conductive Polymer Aluminium Capacitors

Conductive polymer aluminium capacitors are a specific type of solid aluminium capacitor that utilises a conductive polymer as the sole electrolyte material. These capacitors offer exceptional performance characteristics, including very low ESR, high ripple current capability, and extended lifespan. They are often used in demanding applications, such as high frequency switching power supplies, automotive electronics, and industrial automation.

Applications of Aluminium Capacitors

Aluminium capacitors are ubiquitous in the world of electronics, finding applications in various industries in Singapore:

• Consumer Electronics: They are used in smartphones, laptops, televisions, and audio equipment for filtering, smoothing, and energy storage, such as PC power supplies.
• Power Supplies: Aluminium electrolytic capacitors are essential components in DC power supplies for computers, servers, and various electronic devices, ensuring stable and reliable power delivery.
• Automotive: Solid aluminium capacitors and hybrid capacitors are used in automotive electronics, including engine control units, infotainment systems, and electric vehicle powertrains, due to their ability to withstand harsh environments.
• Industrial Automation: They are used in industrial control systems, robotics, and automation equipment for filtering and energy storage.
• Telecommunications: They are employed in telecommunications infrastructure for filtering and smoothing signals.
• Medical Devices: Aluminium capacitors are used in medical equipment for filtering and energy storage, ensuring the reliable operation of critical medical devices.
• Renewable Energy: They are used in solar power systems and wind turbines for energy storage and smoothing.

Buy Aluminium Capacitors from a Trusted Supplier and Manufacturer in Singapore

RS is a trusted supplier, distributor, and manufacturer of aluminium electrolytic capacitors in Singapore. Our catalogue includes a wide range of reputable aluminium capacitor brands including Panasonic, Rubycon, and our own RS PRO line. We also carry ceramic capacitors and other passive components such as fixed resistors to meet any industrial need.

Order aluminium capacitors online from RS today and enjoy fast delivery across Singapore, with next-day delivery and self-collection available. For more details on the ordering process, delivery services, and delivery fees, please refer to our Ordering Page and Delivery Page.