10 min read

Constant power technique and Ragone plot – Electrochemistry & Battery – Application Note 6

Latest updated: August 26, 2021


Both primary and secondary batteries are often tested in terms of energy and power density, as well as, the relationship between the two. Ragone plot is a well accepted way to display it. Application note #6 discusses how to use the Constant Power Discharge (CPW) technique available in EC-lab and BT-lab software for Bio-Logic potentiostats-galvanostats-ZRAs and battery cyclers, to obtain this data in a quick and user-friendly manner.



The aim of this document is to describe the Constant Power (CPW) technique. This technique, available with EC-Lab® software (since V8.10), is applied in a Li-ion battery test and is available with all Bio-Logic instruments.

The Constant Power technique has been designed to study the discharge (eventually the charge) of a battery or a cell (made of intercalation compounds) at successive constant power. The constant power control is made by holding the power (i.e. the factor E*I) to a constant value. During the discharge, the cell potential decreases. In order to hold a constant power, the current is adjusted and will increase. This can be shown on the following figure…


To view the entire application note please click the download button below.

Work smarter. Not harder.

Tech-tips, theory, latest functionality, new products & more.

Subscribe to the newsletter

No thanks!