"Maintenance free" batteries now in use in place of common batteries have

Options

A. Electrode made of lead-lead oxide
B. Electrodes made of calcium-containing lead alloy
C. Non aqueous solvents as medium
D. Platinum electrodes

Answer

To answer the question regarding "maintenance-free" batteries and their components, we can break down the information into clear steps:

### Step-by-Step Solution:

1. **Understanding Maintenance-Free Batteries**:
Maintenance-free batteries are designed to require minimal upkeep compared to traditional batteries. They are often sealed and do not need regular topping up of electrolyte.

2. **Electrode Composition**:
The electrodes in maintenance-free batteries are typically made from a lead oxide material. This is crucial for the battery's electrochemical reactions.

3. **Use of Alloys**:
In maintenance-free batteries, the electrodes are often constructed from a calcium-containing lead alloy. This alloy enhances the performance and longevity of the battery.

4. **Grid Formation**:
The grid in these batteries is made using a combination of metals such as calcium, tin, and lead. This grid structure is essential for supporting the active material and facilitating the flow of electrons.

5. **Non-Aqueous Solvent**:
Some maintenance-free batteries may use non-aqueous solvents instead of traditional liquid electrolytes. This helps in reducing maintenance needs and preventing leakage.

6. **Alternative Electrode Materials**:
In some advanced maintenance-free batteries, platinum electrodes may be used, which provide excellent conductivity and stability.

### Final Summary:
Maintenance-free batteries utilize lead oxide electrodes, often made from calcium-containing lead alloys, and employ a grid structure of metals like calcium, tin, and lead. They may also use non-aqueous solvents or platinum electrodes to enhance performance and reduce maintenance.

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