This article written by Dennis Zogbi, Paumanok Inc. published by TTI Market Eye provides overview and mapping of Conductive Polymer Capacitors: tantalum capacitors and aluminum capacitors material supply chain and its applications.
This article addresses the global market for conductive polymer capacitors in tantalum and aluminum electrolytic dielectrics, with emphasis upon molded chip, vertical chip and radial leaded component configurations.
These small electrolytic capacitors energy storage devices are known for their high capacitance, broad voltage range and volumetric efficiency, but what really separates conductive polymer capacitors from conventional electrolytic capacitor designs is their low equivalent series resistance (ESR), which is the mechanism that allows these small capacitors to release charge rapidly.
A separate economic push for this next-generation capacitor design is the solid-state nature of the polymer in its anode form, which creates an added layer of protection or a ‘self-healing” mechanism that improves the lifetime of the finished part in circuit – a favorite of electrical high-voltage design engineers.
CONDUCTIVE POLYMER TECHNOLOGY: THE FOCAL POINT OF ELECTROCHEMICAL CAPACITOR RESEARCH AND DEVELOPMENT
Conductive polymer capacitors have been the focal point of next-generation electrochemical capacitor technology for more than 30 years. The application of a conductive polymer in the finished capacitor creates a component with extremely low equivalent series resistance that is also resistant to catastrophic failure. In both its tantalum and aluminum dielectric design, the production process for a conductive polymer capacitor is more advanced than that of its traditional legacy counterpart and both tantalum and aluminum product lines have been growing at rates that exceed that of traditional capacitors.
Background of this Article
This article was produced in 2024 and is the continuation of a research thread at Paumanok Publications, Inc. that is the result of the proliferation of polymer cathode technology through the electrolytic segment of the global capacitor industry since 1993. Polymer technology has successfully displaced traditional cathode technologies in both tantalum and aluminum dielectric capacitors and is therefore considered a successful example of disruptive technology.
The conductive polymer cathode system enables more efficient transmission of energy inside the capacitor, and this results in lower equivalent series resistance and a more advanced capacitor design. This article is the extension of research on conductive polymers and conductive polymer capacitors that Paumanok Publications, Inc. has conducted in 2006, 2010, 2015, 2018 and 2024. It includes separate market study investigations on tantalum and aluminum dielectrics between 1988 and 2024.
2024 SOLID POLYMER CAPACITORS TECHNOLOGY OVERVIEW:
SOLID POLYMER CAPACITOR TECHNOLOGY COMPARISON – ALUMINUM AND TANTALUM
The following chart illustrates the state of the art in electrolytic capacitors. These designs have been deployed in digital electronics where high voltage, high capacitance, small space and challenging environment are key considerations. The similarity between the two is they employ a conductive polymer cathode system instead of legacy materials such as solid manganese or more popularly liquid electrolytes.
Molded Tantalum Chip Capacitors
The molded chip design is manufactured by molding the capacitor pellet in a fixed shape mold after the pellet has been attached to a lead frame. Molded chips are available in standard A through D case sizes, larger E case sizes (a thicker version of the D case that allows more capacitance) and now the smaller P, J and K sizes available from global vendors as well. The molded tantalum chip capacitor is the largest segment of the tantalum capacitor market based upon configuration with 86% of global consumption value for FY 2024.
Molded chips are used in almost every end-use market, especially computers, handsets, automobiles, cameras, game consoles and many additional modern electronic devices. Today, surface mount tantalum capacitors are designed for their automatic insertion and are accordingly packaged in embossed plastic carrier tapes that are specifically designed for use with pick and place insertion equipment.
Solid Polymer Vertical Chip Aluminum Capacitors (V-Chip)
Vertical chip aluminum electrolytic capacitors represent a fast growth portion of the aluminum capacitor industry in FY 2024 and has shown the largest amount of growth over the past five years in terms of both value and volume of consumption. This has been caused by demand from the flat panel display television set market and from various portions of the computer industry. Vertical chip aluminum capacitors continue to fill slots previously held by radial leaded aluminum capacitors designs.
The need for a more volumetrically efficient aluminum electrolytic capacitor solution to satisfy the growing need of the flat panel TV market, the notebook and netbook computer market, and various consumer audio and video imaging market, such as game console, DVR and cable set top box have increased demand for these devices and the emerging growth markets in electric vehicle propulsion, for battery management, charging circuits, inverter and converter components.
Horizontal Polymer Aluminum Chip Capacitors (H-Chip)
The horizontal aluminum electrolytic capacitor market represents a molded chip technology with aluminum anode that matches molded tantalum chip capacitor case sizes. Intended markets match that of tantalum capacitors and, therefore, these devices can be found in computers, automotive electronics, game consoles and related markets. This is where the majority of new polymer cathode aluminum designs can be found.
CONDUCTIVE POLYMER CAPACITOR MATERIALS: TECHNOLOGY OVERVIEW
The Different Types of Conductive Polymers Employed in Capacitor Cathodes
There are three conductive polymers currently in wide use as cathode materials in the capacitor industry. These include polypyrrole, polythiophene and polyaniline and multiple derivations thereof. Polythiophene and polypyrrole are the polymers that have the largest usage across both tantalum and aluminum electrolytic capacitor markets and are the most heavily consumed worldwide.
The Difference Between Polypyrrole, Polythiophene and Polyaniline in the Finished Capacitor
Polypyrrole: Polypyrrole is used in polymer aluminum and tantalum capacitors when the operating temperature of the capacitor on the printed circuit board does not exceed 85° C. These tantalum and aluminum chip applications are limited to consumer audio and video imaging products. Polypyrrole is easy to find, abundant and inexpensive.
Polythiophene: Polythiophene when mixed with a polymer enables the finished capacitor product to operate up to 125° C, where it is most needed. The space above 85° C, with emphasis upon 105° C and 125° C, are needed for telecommunications infrastructure, industrial and automotive applications where larger case sizes are used and where performance is mission critical.
Polyaniline: This conductive polymer is used as a sealer and in conjunction with polythiophene. Polyaniline is not used as of yet as the cathode polymer because its coverage is not as good as polythiophene; however, the thicker polyaniline can be used as a sealer for the anode because polythiophene has a problem covering the ends of the squares of the chip anode.
Production Process for Conductive Polymer Anodes—Methods of Polymer Penetration
The top electrolytic scientists truly engaged in conductive polymer research for solid electrolytic applications consider most profitable system for conductive polymer solid electrolytic capacitors to be a
- Very efficient conductive polymer application process
- Least wasteful process that limits loss of the monomer or polymer
- Greatest penetration and coverage of the polymer into the anode.
For those who dip their anodes, it is key to limit the number of cathodic baths from the current 9 dips to one dip. This would be the best method by which to limit the massive waste in the system. But this only applies to those who dip.
It is generally believed, however, that the electro polymerization method, although costly to install and difficult to master, is a better process for creating conductive polymer anodes than dipping.
Electro-Polymerization Method: The electro-polymerization method is considered the best method for obtaining maximum coverage of the anode with the polymer cathode. This method employs an electro-polymerization process that employs pressure to force the polymer into the nooks and crannies of the tantalum anode.
Dipping Method: The dipping method involves the mechanical manipulation of the capacitor anode into multiple cathodic baths containing the polymer in its various forms. Up to nine dips may be performed. The increasing number of dips ensures complete coverage of anode with the polymer cathode material.
Current Conductive Polymer Pricing and Changes in The Market
PeDOT polymer must be purchased as two separate products and mixed together by the manufacturer. This includes the poly (ethyl) dioxithiopene (PEDOT) monomer and an oxidizer. The monomer is the more expensive of the two process materials, and the oxidizer costs about 10% of the monomer price but four times as much volume is used.
Variations on Construction and Capacitor Configuration
What is interesting in the industry is that conductive polymer technology is replacing traditional cathodes in two separate product configurations currently on the market. Therefore, we find conductive polymer cathodes in molded chip capacitors. These dielectrics form the core of growth for the future foundation of the electrolytic chip capacitor for digital electronics. These dielectrics are also produced in solid format, which tells the consumer that no liquid is contained in the capacitor for safety reasons.
Also, the solid polymer aluminum capacitor is produced in the V-chip, or vertical format. There is also the radial leaded aluminum capacitor market which is consuming liquid and conductive polymer, which is also growing because of safety concerns surrounding radial leaded capacitors with conventional liquid electrolytes. Radial leaded capacitors with liquid and polymer electrolytes operate at a higher frequency range when compared to solid polymer capacitors. (The focus of this report is on polymer aluminum capacitors, but it is important for the reader to understand the keen relationship between tantalum capacitors and aluminum capacitors that contain polymers, not only from a technical perspective but from a perspective of competition between the two dielectrics as well).
END-USE MARKETS
The following section of this article offers the reader a glimpse of the market breakdown for conductive polymer capacitors with respect to consumption by end-use market segment.
Conductive Polymer Capacitors by End-Use Market Segment: FY 2024
Conductive polymer capacitors have made inroads into a variety of end-use markets as is shown in the chart below. It is important to note that consumption of conductive polymer capacitors, regardless of dielectric, differs from consumption of electrolytic capacitors as a whole. Due to the fact that conductive polymer capacitors offer the unique combination of low ESR, higher reliability, high capacitance and a small case size, the end-use market who needs those criteria in a capacitor most of all is the computer industry.
Computers and Business Machines
A detailed analysis of product literature associated with conductive polymer capacitors, regardless of dielectric, shows that the primary end-market for consumption is in the computer and computer peripheral markets, and these markets are concentrated in Greater China. Many of these conductive polymer capacitors are sold to EMS companies that manufacture computers under contract with other brand name companies. Computers require low ESR, high capacitance and higher operating voltages in their capacitors, which lend themselves to polymer designs which are both tantalum and aluminum in design.
DC/DC Converters and SMPS: The DC/DC converter brock and the switchmode power supply products constitute the largest end-use market for conductive polymer capacitors, including both solid and liquid versions in tantalum and aluminum dielectric capacitors. The power supplies are in turn consumed in computers, flat panel displays, TV sets and telecommunications infrastructure equipment. Conductive polymer capacitors are consumed in power supplies and converters because they offer superior signal quality and low distortion in power smoothing and conditioning.
CPU and VGA: Other major circuit applications in computers for conductive polymer capacitors, including both tantalum and aluminum polymer capacitors, are for circuits associated with the central processing unit and for video graphics cards. Conductive polymer capacitors are used for voltage smoothing and noise absorption of CPU, memory and various LSI functions.
Flat Panel Displays: Conductive polymer capacitors in both tantalum and aluminum are consumed in flat panel computer displays for primary stabilization of the LCD driver and timing controller.
USB Memory Sticks: Conductive polymer capacitors in tantalum are consumed in memory sticks (dongles) for smoothing the circuits and for clean data transfer.
Copiers and Printers: Conductive polymer aluminum capacitors, especially liquid polymer versions, are consumed in computer peripheral equipment, especially copiers and printers.
Video Projectors: Some video projectors employ aluminum polymer capacitors are stabilization of audio and video circuits in advanced projectors.
Consumer AV and Home Theatre
This is followed by applications in consumer audio and video imaging equipment, with major emphasis upon applications in video game consoles where we find demand in Japan and the U.S., with actual consumption, once again, largely in greater China. The other market with significant activity regarding the usage of conductive polymer capacitors is in the digital still camera market and the digital video camera market, which needs low ESR electrolytic for rapid power up and switching of functions.
LCD TV Monitors: Conductive polymer capacitors in both tantalum and aluminum are consumed in flat panel computer displays for primary stabilization of the LCD driver and timing controller.
Cable Set Top Box: Solid polymer aluminum capacitors and liquid polymer aluminum capacitors are consumed in the cable set top box market for residential cable and digital TV worldwide.
MP3 Audio Player: Polymer tantalum chips and solid polymer aluminum chips are both consumed in MP3 audio players for advanced audio stabilization circuits, however, this market has largely been cannibalized by smartphones.
Digital Cameras: Solid polymer aluminum and conductive polymer tantalum capacitors are both consumed in digital video and audio circuits in handheld video cameras.
Home Stereo: Polymer aluminum capacitors are consumed in advanced home stereo and home theatre products for audio stabilization.
Game Consoles: Polymer aluminum and polymer tantalum capacitors are both consumed in video graphics cards in game consoles.
Industrial Electronics
Another key market for conductive polymer capacitors is in the power supply market, especially for ultra-small DC/DC converter “bricks” which need the low ESR of the conductive polymer capacitor for quick power up.
Power Supplies and DC/DC Converters: Conductive polymer capacitors are consumed in power supplies and converters because they offer superior signal quality and low signal distortion.
LED Lamps and Backlighting: Conductive polymer capacitors in both solid polymer aluminum and solid polymer tantalum are consumed for the stabilization of the LCD driver circuits in flat panel display backlighting and in some LED lamps.
Energy Harvesting: Energy harvesting services are consumed in wearable electronics for example, for energy is derived from the external source, such as the kinetic movement of clothing. Conductive polymer capacitors in ultra-small, molded chip designs are consumed here for their power smoothing ability.
Test and Measurement Equipment: Because of the precise nature of academic and trade laboratory test and measurement equipment, manufacturers will typically use the best components available, and this includes conductive polymer capacitors- primarily in tantalum dielectric.
Coin Processing Machines: Coin processing machines for arcades and laundromats will also employ large case size conductive polymer capacitors for power smoothing in the power supplies.
Barcode Scanners: Barcode scanners are a low volume, high value business wherein vendors usually employ the highest quality components, including solid polymer tantalum conductive polymer capacitors.
Fingerprint ID: Fingerprint identification devices for homeland security are also devices that consume conductive polymer aluminum and tantalum capacitors for power smoothing.
CCTV: Some CCTV devices, which are in fact digital video cameras, also consume conductive polymer aluminum and tantalum capacitors in their solid format for power smoothing.
Wireless Access Equipment
Almost all wireless device consumption in conductive polymer is tantalum dielectric only and limited primarily to smartphone consumption for battery and display stabilization.
Smart Phones (Polymer Tantalum): Smartphones employ a few (one or two) conductive polymer tantalum capacitors for stabilization of battery voltage, and stabilization for display. Only tantalum is used at this time.
GPS Devices: GPS devices are a favorite end-use market for conductive polymer capacitors. Similar in many respects to an advanced smartphone, handheld GPS employ conductive polymer capacitors for audio and video circuits as well as stabilization of the battery circuit and stabilization of the display.
Automotive Electronics
Another important market where conductive polymer capacitors are making inroads is in the automotive electronic subassemblies markets, primarily for applications in driver information equipment, such as GPS, inertial mapping and diagnostic tools.
Automotive Inertial Mapping/GPS: Like handheld GPS devices, automotive GPS devices also consume conductive polymer capacitors in both aluminum and tantalum dielectric, primarily for stabilization of the display circuits.
Automotive – Battery Electric Vehicle Propulsion: The opportunity for tantalum and V-chip aluminum capacitors that employ polymer in the cathode for fire safety will be consumed in large volumes and with great value for the BEV propulsion system. The demand will redefine the value of polymer capacitor shipments.
The movement toward solid-state batteries that employ polymer cathodes, capacitors will also be sourced in such a way with emphasis upon solid polymer aluminum capacitors for inverter, converter, charger and battery management circuits. Both aluminum and tantalum can be employed to 125° C and tantalum as high as 150 °C in polymer. Aluminum is applicable to 130 °C and moving toward 150 °C. Both products will be in great demand for the BEV market to go to 15 million cars by 2029 as forecasted by manufacturers.
Telecommunications Infrastructure:
Telecom infrastructure applications for conductive polymer capacitors are primarily for smoothing of power supplies.
Base Stations: Base station power supplies employ conductive polymer aluminum and tantalum capacitors for power smoothing.
Routers: Routers used in data communication switches also employ conductive polymer aluminum and tantalum capacitors for power smoothing.
Medical Electronics
Medical electronics employ both aluminum and tantalum polymer capacitors and are used primarily for power smoothing and for display and battery circuit stabilization in handheld and display mounted medical devices.
Portable Medical Meters: Handheld medical diagnostic equipment employs conductive polymer capacitors for stabilization of the battery circuit and stabilization of the display.
Medical Monitors: Medical monitors employ conductive polymer capacitors for stabilization of the display.
Pulse Oximeters: These medical devices check the oxygen levels in blood and are small handheld electronic devices that also employ conductive polymer capacitors for stabilization of the display circuits.
Aerospace Equipment
Polymer tantalum capacitors are used primarily for power smoothing and for power smoothing in navigation equipment and radar circuits.
Navigation Equipment: Aerospace navigation equipment employ conductive polymer capacitors, almost exclusively tantalum.
Radar Circuits: Radar circuits for pulse forming networks also employ conductive polymer capacitors – once again – almost exclusively tantalum.
SUMMARY AND CONCLUSIONS
This article maps out the complex ecosystem for conductive polymer type capacitors, noting that conductive polymer capacitors are manufactured in both tantalum and aluminum dielectrics and are available in specific configurations including molded tantalum chip, molded aluminum horizontal chip, vertical chip and radial leaded designs.
Tantalum polymer capacitors are solid-state constructions, as are horizontal chip aluminum and a large portion of the vertical chip designs. Liquid polymer capacitors are also available on the market and are available in radial leaded polymer aluminum and some of the vertical chip aluminum markets. End-markets that require the low ESR of a polymer capacitor include the computer, consumer, industrial, automotive, medical and aerospace end markets.