🎧 Audio Podcast Overview
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🎬 Video Overview
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🧠 Interactive Mind Map
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📖 What You'll Learn
Key topics covered in this chapter
- Primary cells — the dry cell, its construction and why it must not be recharged
- Secondary (rechargeable) cells — the lead-acid battery, its plates and electrolyte
- Battery ratings — voltage, amp-hour capacity, and cells in series versus parallel
- Battery life and internal resistance — sulphation, cycle life and how IR is measured
- Testing lead-acid batteries — the hydrometer, specific gravity and state of charge
- Charging — constant-voltage versus constant-current methods and gassing safety
- Nickel-cadmium, sealed lead-acid, thermocouples and photo-cells