B41689L8477Q001

The B41689L8477Q001 is an axial-lead aluminum electrolytic capacitor from TDK EPCOS’s high-performance B41689 series, designed specifically for automotive and industrial applications requiring high ripple current handling and robust mechanical performance.

With a rated capacitance of 470µF at 63V DC and a wide operating temperature range of -55°C to +150°C, this capacitor delivers exceptional ripple current capability of 4.1A at 10kHz and 125°C ambient — significantly higher than standard single-ended capacitors of comparable size. The low equivalent series resistance (ESR) of just 132mΩ at 100Hz/20°C minimizes self-heating under high ripple loads, contributing to extended service life.

The B41689 series features advanced design innovations including optimized internal thermal resistance through corrugated winding technology, which reduces hot-spot temperatures and further enhances ripple current capacity. The axial-lead construction with long axial leads provides superior mechanical stability and vibration resistance up to 20g (case-fixed), making it well-suited for under-hood automotive environments and industrial machinery subject to mechanical stress.

Finished with an orange PET insulation sleeve and qualified to AEC-Q200 and IEC 60384-4 standards, the B41689L8477Q001 is supplied in axial pallet packaging (160 pieces per pack, MOQ 3,200 pieces) and is fully RoHS compliant. With a rated useful life exceeding 10,000 hours, this capacitor offers long-term reliability in the most demanding applications.

An aluminum electrolytic capacitor operates through an electrochemical process where an insulating oxide layer (aluminum oxide, Al2O3) formed on the surface of an aluminum foil anode acts as the dielectric. The cathode consists of a second aluminum foil in contact with a liquid or semi-liquid electrolyte that fills the space between the anode and cathode foils.

In the B41689L8477Q001, both the anode and cathode foils are etched to dramatically increase their effective surface area, allowing high capacitance in a relatively compact volume. The anode foil is electrochemically oxidized (formed) to create a uniform aluminum oxide dielectric layer whose thickness is proportional to the rated voltage — in this case, 63V.

The two foils are separated by porous paper spacers saturated with a conductive electrolyte (typically based on organic solvents like GBL or ethylene glycol with dissolved salts). The entire assembly is wound into a cylindrical winding element and inserted into an aluminum can case. An axial lead is attached to each end of the winding — one to the anode tab, one to the cathode tab — enabling through-hole axial mounting.

When a DC voltage is applied with correct polarity (positive to anode), the oxide dielectric layer blocks current flow while the capacitor stores charge electrostatically across the dielectric. The electrolyte provides the electrical connection between the cathode foil and the actual cathode dielectric surface on the anode foil, effectively extending the cathode electrode throughout the winding.

The B41689 series employs advanced low-ESR design techniques including optimized electrolyte formulations, thicker foil conductors, and improved internal connections to minimize equivalent series resistance. This low ESR enables high ripple current handling with lower heat generation, which directly translates to longer useful life and higher reliability in high-current power supply applications.

The capacitor’s useful life follows the Arrhenius relationship: every 10°C reduction in operating temperature roughly doubles the service life. At full rated conditions (63V, 125°C, rated ripple current), the B41689L8477Q001 provides more than 10,000 hours of reliable operation.

Note: This is a polarized capacitor. The positive terminal must be connected to the higher voltage potential. Reverse voltage application may cause catastrophic failure including venting or explosion. The orange PET insulation sleeve covers the aluminum can case and provides electrical isolation.

• Automotive powertrain electronics — engine control units, transmission controllers
• Automotive body electronics and infotainment systems
• DC-DC converter input and output bulk capacitance
• Switch-mode power supplies (SMPS) filtering
• Audio power amplifier power supply decoupling
• Industrial motor drives and inverters
• Energy storage and hold-up capacitor applications
• High-temperature industrial electronics (up to 150°C)
• Heavy equipment, construction machinery, and agricultural vehicles