SDAA084 April   2026 BQ25856-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2How to Extend the Life of Supercapacitors
    1. 2.1 Effects of Voltage
    2. 2.2 Effects of Current
    3. 2.3 Effects of Temperature
  6. 3Supercapacitor ESR and Capacitance
    1. 3.1 Estimating Capacitor Capacitance and ESR
    2. 3.2 Measuring Supercapacitor Health With The BQ25856-Q1
    3. 3.3 Estimating the Capacitance and ESR in Reverse Mode
  7. 4Summary
  8. 5Appendix - Example MCU Code for the BQ25858-Q1
  9. 6References

4 Summary

Supercapacitors have large benefits over electrolytic capacitors or batteries. Supercapacitors have a much greater power density and much longer lifetime compared to batteries. Also, supercapacitors can store more energy than electrolytic capacitors. However, supercapacitors still age and the usable power and energy decreases over time. The BQ2585X-Q1 and BQ2575X family of ICs can estimate the ESR and capacitance of supercapacitors. This information helps track the health of the supercapacitor and can be used to estimate the end-of-life for the capacitor.