What Is a Negative Cathode?

The negative electrode refers to the lower potential (potential) end of the power supply. In the primary battery, it refers to the electrode that acts as an oxidizer. The battery reaction is written on the left. In the electrolytic cell, it refers to the electrode that plays a reducing role, which is different from the primary battery. From a physical point of view, it is the pole where electrons flow out of the circuit.

The negative electrode refers to the lower potential (potential) end of the power supply. In the primary battery, it refers to the electrode that acts as an oxidizer. The battery reaction is written on the left. In the electrolytic cell, it refers to the electrode that plays a reducing role, which is different from the primary battery. From a physical point of view, it is the pole where electrons flow out of the circuit.

Chinese name

negative electrode

Foreign name

negative electrode

Negative electrode overview

Negative electrode: The electrode that loses electrons and undergoes an oxidation reaction.

External circuit: electrons flow from negative to positive; current flows from positive to negative.

Directional movement of anion and cation in the internal circuit: the anion moves to the negative electrode, and the cation moves to the positive electrode. ^[1]

Identification of negative and positive electrodes

Judgment of positive and negative electrodes of negative cell

From the electrode reaction

From the electrode material

2. Current direction of internal and external circuits and moving direction of conductive particles

3.General conditions that constitute a simple primary battery

Two active conductors are used as electrodes. The two electrodes are kept in contact and inserted into the electrolyte solution (loop). The total reaction is a spontaneous (release of energy) redox reaction. ^[2]

Identification of positive and negative electrodes of negative battery

method one:

When the "+" and "-" signs are blurred, the battery poles coated with red represent the positive pole, and the poles coated with blue mark are the negative pole. If the battery is used for a long time, the color may become dark. But generally speaking, a slightly thicker pole is a battery positive electrode, and a slightly thinner pole is a battery negative electrode.

Method Two:

Use the DC voltmeter to determine the positive and negative poles of the battery. Connect the battery to the DC voltmeter. Under the normal condition of the voltmeter needle, the positive terminal of the voltmeter is the positive terminal of the battery, and the negative terminal of the voltmeter is the negative terminal of the battery.

Method three:

Judging the positive and negative poles of batteries of unknown polarity by means of high-frequency dischargers and batteries with polarity marks. Using a high-frequency discharger to test and compare two batteries, the ends with the same response have the same polarity. However, this trick requires a battery of known polarity and a more professional discharger.

Method four:

Judging the positive and negative electrodes of the battery by using salt water. Connect one lead wire to each end of the battery, insert it into the salt water, and check the wire ends. The battery bubble generating end is connected to the battery negative electrode, and the battery bubble generating end is connected to the battery positive electrode. There is one thing to note in this trick. The container holding the saline solution must not be conductive. Generally, a porcelain bowl is better. In addition to common salt water, alkaline water, dilute sulfuric acid, and the like can be used as long as they can form an electrolyte.

Method five:

An electric bulb is indirectly connected to the two poles of the battery to form a loop. Put a small magnetic needle under the wire that forms the circuit. The direction of the magnetic needle should now be perpendicular to the direction of the wire. Judging by the right-hand rule, the direction pointed by the thumb is the direction of current flow. The current flows from the positive battery and back to the negative battery.