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Assistance needed? Please contact JiAnGHAi EuroPE GmbH +49 (0)2151 652088-72 or info@jianghai-europe.com

Life Time Estimation

Lifetime Estimation of Aluminum Electrolytic Capacitors from Jianghai

To estimate the Lifetime of a non-solid Aluminum Electrolytic Capacitor from

Jianghai, the following formulas can be utilized. The

Lifetime depends mainly on the ambient temperature, the ripple current and, within certain limits, the operating voltage applied.

Other parameters may also affect the Lifetime. Moreover, L

influence on the numerical result.

Jianghai offers a high transparency by publishing the different typical definitions of Lifetimes in

each datasheet. Lifetime estimations are approximations by nature.

Please let

JiAnGHAi EuroPE confirm any result before using it. The formulas given here do not constitute part of a contract nor

of a specification. The formulas do not cover additional aging effects of certain electrolytic systems or other chemical effects. Please

contact us should you need Lifetime estimates for Solid Electrolyte Polymer Capacitors. Also the dimensions of the components

may have an effect. Forced cooling or other additional cooling-methods have a strong impact on the Lifetime and are not covered

by the formulas.

For the estimation and interpretation of Lifetime, a close collaboration with

JiAnGHAi EuroPE is strongly advised.

Structural formula:

L = L

Where:

L

Total Lifetime

L

0

Lifetime under Rated Ripple Current at Upper

Category Temperature (see catalogue)

K

T

Temperature Factor

K

R

Ripple Current Factor

K

V

Voltage Factor

1. K

Aluminum Electrolytic Capacitors follow roughly the 10 K rule of Arrhenius. It is possible to estimate the

Lifetime by rule of thumb: When the operational temperature is reduced by 10 K, the Lifetime will double.

The formula for K

K

T

10K

Where:

T

0

Rated Temperature

T

A

Ambient Temperature, Upper Category Temperature

2. K

the following formula:

K

∆ T

0

10K

( )

A

A= 1 –

I

A

I

R

2

With:

Where:

I

A

Actual Rated Ripple Current

I

R

Ripple Current at Upper Category Temperature (databook value)

ΔT

0

Core Temperature Rise of the capacitor

(typically 5K for T

K

i

Basis, defined as

T

I

K

I

K

T

85°C

K