Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Internal Battery Resistance Change During Use

Name: Mikus
Status: student
Grade: 9-12
Country: Latvia
Date: Spring 2012


Question:
Does the internal resistance of a battery change if the battery is being discharged?

Replies:
Yes. Batteries play a lot of messy games with their internal resistance. The resistance can depend on temperature, percent-of-charge-remaining, recent history of current drain, and battery aging. Each kind of battery (lithium, alkaline, lead-acid, Ni-Cd, NiMH) has a different set of behaviors. I have seen a lithium battery, when suddenly asked to push a large load, allow its output voltage to drop a lot at first, because its internal resistance was high, because the battery was cold. Then the large current flowing through that internal resistance warmed up the battery, and the voltage delivered actually increased with time, for a little while.

Jim Swenson


Mikus

There are two types of batteries in discussions of electricity, an ideal battery where the voltage remains constant regardless of the current drain, and real batteries. The output voltage of real batteries does vary according to temperature and current load.

So, yes, the internal resistance of a battery does change if the battery is being discharged.

Sincere regards, Mike Stewart


Click here to return to the Physics Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory