Equivalent circuit for a battery.

[Yam]

Homework Statement

An engineer is trying to model a lithium battery with a thevenin equivalent circuit. She first connects a voltmeter across the battery and gets a reading of 3.7V. She then connects 0.5 Ohms resistor across the battery terminals. The reading now drops to 3.2V. Draw the equivalent circuit for the battery and work out the circuit parameters.

Homework Equations

I understand how to derive the equivalent circuit but i do not understand what circuit parameters represent

The Attempt at a Solution

V_OC=3.7V
R=? I do not know how to derive the internal resistance of the battery also

Now, i don't understand what the circuit parameters mean. What are they asking for?[/B]

 

[gneill]

Homework Statement

An engineer is trying to model a lithium battery with a thevenin equivalent circuit. She first connects a voltmeter across the battery and gets a reading of 3.7V. She then connects 0.5 Ohms resistor across the battery terminals. The reading now drops to 3.2V. Draw the equivalent circuit for the battery and work out the circuit parameters.

Homework Equations

I understand how to derive the equivalent circuit but i do not understand what circuit parameters represent

The Attempt at a Solution

V_OC=3.7V
R=? I do not know how to derive this also

In Relevant equations above you stated that you knew how to derive the equivalent circuit.

Now, i don't understand what the circuit parameters mean. What are they asking for?

In this case they are looking for the component values for the Thevenin equivalent circuit (Thevenin voltage and Thevenin resistance).

Show us what you know!

 

[CWatters]

Post the equivalent circuit of the battery and 0.5 Ohm load resistor.

 

[Yam]

Haha! Yes! i solved it after 2 hours haha! thanks guys

 

[CWatters]

What did you get for the internal resistance?