A Novel Health Level Estimation of Liquid Aluminum Electrolytic Capacitor for Enterprise SSD Applications

As one of the most common basic electronic components on the circuit board, liquid aluminum electrolytic capacitor is widely used in integrated circuits. In the field of enterprise Solid State Device (eSSD), liquid aluminum electrolytic capacitors are used as energy storage capacitors. At the moment of sudden power failure of eSSD power supply, the capacitor provides power for the system to ensure the data integrity of eSSD. Due to the physical characteristics of electrolyte volatile conductance of liquid aluminum electrolytic capacitor, it will lead to the decrease of capacitance value. It is necessary to study the capacitance attenuation curve of liquid aluminum electrolytic capacitor. This paper introduces several methods for estimating the life of aluminum electrolytic capacitors, but these algorithms are not suitable for SSD application scenario, and the accuracy of the algorithms is not high in SSD application scenario. Based on the demand of eSSD feasibility analysis for the life of liquid aluminum electrolytic capacitor, a new estimation method is proposed to estimate capacitor health level. According to the application scenario of eSSD, a series of DOE (Design of Experiment) tests are made by using partial factor design method, and the capacitance attenuation curve and influence factors of liquid aluminum electrolytic capacitor are obtained. The mixed model is used to fit the attenuation formula of liquid aluminum electrolytic capacitor, and the error is analysed. Compared with other life estimation methods, the proposed life estimation method is more accurate in SSD field, which provides sufficient basis for eSSD engineers to select the liquid aluminum electrolytic capacitor.

I. Introduction

With the development of AI technology, there is an increasing demand for the use of eSSD in various fields. Data integrity and reliability are one of the most important characteristics of eSSD. Power Loss Protection (PLP) is one of the means for eSSD to ensure data integrity. PLP function deals with unexpected situations such as sudden interruption of ESSD power supply through the release of energy storage of liquid aluminum electrolytic capacitor. However, the electrolyte of liquid aluminum electrolytic capacitor will volatilize, which leads to the decrease of the capacitance of aluminum electrolytic capacitor [1], and it will affect the function of PLP. The content of this paper is the capacitance attenuation of liquid aluminum electrolytic capacitor under different temperatures and voltages.