Secondary batteries, also known as rechargeable batteries, are recharged by applying a reverse current to them. This process reverses the electrochemical reactions that occur during discharge, effectively restoring the battery's original chemical composition and energy storage capacity.
The Recharging Process Explained
The ability to recharge a secondary battery stems from the reversibility of the electrochemical reactions within the cell. When the battery discharges, chemical compounds at the electrodes change, releasing electrical energy. Recharging reverses this process:
- Applying Reverse Current: An external power source forces electrons to flow in the opposite direction of discharge.
- Reconstituting Active Materials: According to the provided reference, "the original active materials at the two electrodes can be reconstituted chemically and structurally by the application of an electrical potential between the electrodes to 'inject' energy." This means the chemical compounds that were altered during discharge are converted back to their original state.
- Energy Storage Restoration: As the chemical compounds are restored, the battery regains its ability to store electrical energy.
Examples and Practical Insights
Consider a common Lithium-ion battery. During discharge, lithium ions move from the negative electrode to the positive electrode. Recharging forces these lithium ions back to the negative electrode. This movement is facilitated by the reverse current, essentially undoing the discharge process.
Key Takeaways
| Feature | Description |
|---|---|
| Recharge Method | Applying a reverse current. |
| Electrochemical Process | Reversing the chemical reactions that occurred during discharge. |
| Active Material Restoration | Reconstituting the original chemical compounds at the electrodes. |
| Energy Restoration | Restoring the battery's capacity to store electrical energy. |
