Secondary Batteries
Secondary batteries, unlike primary batteries that can only be used once, are capable of being recharged by reversing the electrochemical reactions that occur during discharge. This feature significantly enhances their utility, especially in applications such as electric vehicles, portable electronics, and backup power systems.
Key Types of Secondary Batteries
The section highlights two notable examples of secondary batteries:
1. Lead Storage Battery: Commonly used in automobiles, consisting of a lead anode and lead dioxide cathode, interspersed with a sulphuric acid electrolyte. During discharge, the following reactions occur:
- Anode Reaction:
$$\text{Pb}(s) + \text{SO}_4^{2-}(aq) \rightarrow \text{PbSO}_4(s) + 2e^-$$
- Cathode Reaction:
$$\text{PbO}_2(s) + \text{SO}_4^{2-}(aq) + 4\text{H}^+(aq) + 2e^- \rightarrow \text{PbSO}_4(s) + 2\text{H}_2O(l)$$
2. Nickel-Cadmium Cell: Known for longevity but high manufacturing costs, it operates similarly by allowing rechargeable processes through suitable electrode reactions.
Understanding the operational principles of secondary batteries is crucial for optimizing their performance and enhancing sustainability in energy consumption. This section ultimately emphasizes the significance of these batteries in modern energy solutions.