In the context of electricity, an accumulator refers to a storage battery, specifically a group of rechargeable secondary cells. The term is commonly used to describe batteries that store and release electrical energy, allowing for repeated charging and discharging cycles. One familiar example of an accumulator is the lead–acid car battery.
Here are some key points about accumulators in the context of electricity:
- Storage Battery: An accumulator is a type of storage battery designed for the accumulation and storage of electrical energy. It consists of one or more individual cells, each capable of storing and releasing electrical charge.
- Rechargeable Cells: Accumulators are rechargeable, meaning that they can be charged multiple times by applying an external electrical current. This feature distinguishes them from non-rechargeable batteries.
- Lead–Acid Accumulator: The lead–acid accumulator is a widely used type, especially in automotive applications. A standard car battery typically consists of six lead–acid cells connected in series. The electrodes are made of lead and lead oxide, immersed in a sulphuric acid electrolyte.
- Charging Mechanism: Accumulators are charged by an external power source, such as a car alternator or dynamo in the case of a car battery. During charging, a chemical reaction occurs within the cells, converting lead sulfate back into lead and lead oxide.
- NiFe Cell: Another type of accumulator is the NiFe (Nickel-Iron) cell. It features electrodes made of nickel and iron and uses a potassium hydroxide electrolyte. NiFe cells have been historically used for various applications, including backup power systems.
- Applications: Accumulators find widespread use in various applications, including automotive, uninterruptible power supplies (UPS), renewable energy systems, and portable electronic devices. They provide a reliable and rechargeable source of electrical power.
Accumulators play a crucial role in storing energy from intermittent sources (such as solar or wind) and delivering it when needed, making them integral to modern electrical systems.
The lead–acid car battery is a typical example of an accumulator. The battery has a set of grids immersed in a sulphuric acid electrolyte. One set of grids is made of lead (Pb) and acts as the anode and the other set made of lead oxide (PbO2) acts as the cathode.