# Why does current continue flowing in a circuit?

Sorry for the amateur question, but I'm having trouble understanding this phenomenon.

In a closed circuit, electron current flows from the negative terminal of a battery to the positive terminal. But why does the current continue flowing? Shouldn't it reach equilibrium once all the electrons have been transferred to the positive side?

• Don't you mean "shouldn't equilibrium be reached when enough electrons have travelled from negative to positive side so they are equal on both sides?" – DKNguyen Mar 16 at 23:57
• – MarkU Mar 17 at 0:04
• Capacitors do decay down to equilibrium. But batteries aren't capacitors. Batteries are electron-pumps. Batteries don't store any charge (pumps don't store the stuff being pumped.) Instead the path for current is right through the middle of the battery, then back out via the second wire. (Remember, battery-electrolyte is a good conductor! Shouldn't it just short the two plates together?) – wbeaty Mar 17 at 2:59

Chemical reactions in the battery move the electrons that arrive at the positive terminal through the battery to the negative terminal to pass through the circuit again.

(For the pedants: I know there are positive ions involved, but I hope this will satisfy Lily.)

• Thanks very much :) . This is a helpful answer. – Lily Morgan Mar 18 at 1:39

A chemical reaction in a battery causes it to produce voltage and deliver current to a load. Remove or disable the chemicals then the reaction and the current stop.

A battery has many electrons to give from the negative side and many holes (where electrons are missing) to receive electrons on the positive side. When the electron flow starts to equalize, the battery is becoming discharged. In order to get electrons to flow again, you have to charge the battery. So the electrons do eventually equalize if you leave the circuit for long enough.

Shouldn't it reach equilibrium once all the electrons have been transferred to the positive side?

Yes. That's called a dead battery.

• this is more like the explanation for a capacitor than a battery – BeB00 Mar 17 at 4:04