Primary And Secondary Cell
A primary cell also referred to as disposable battery is a battery that is designed to be used once and discarded, and not recharged with electricity and reused like a secondary cell. In general, the electrochemical reaction occurring in the cell is not reversible, rendering the cell unrechargeable. As a primary cell is used, chemical reactions in the battery use up the chemicals that generate the power; when they are gone, the battery stops producing electricity. Primary cells are made in a range of standard sizes to power small household appliances such as flashlights and portable radios.
High specific energy, long storage times and instant readiness give primary batteries a unique advantage over other power sources. They can be carried to remote locations and used instantly, even after long storage; they are also readily available and environmentally friendly when disposed.
A rechargeable battery, storage battery, or secondary cell, is a type of electrical battery which can be charged, discharged into a load, and recharged many times, as opposed to a disposable or primary battery, which is supplied fully charged and discarded after use.
Secondary Cell is composed of one or more electrochemical cells. The term “accumulator” is used as it accumulates and stores energy through a reversible electrochemical reaction. Rechargeable batteries are produced in many different shapes and sizes, ranging from button cells to megawatt systems connected to stabilize an electrical distribution network.
Rechargeable batteries typically initially cost more than disposable batteries, but have a much lower total cost of ownership and environmental impact, as they can be recharged inexpensively many times before they need replacing. Some rechargeable battery types are available in the same sizes and voltages as disposable types, and can be used interchangeably with them.
Rechargeable or disposable batteries are both good battery choices for electronic applications. Disposable batteries are largely used for powering low voltage devices that are not used often — such as flashlights, calculators, clocks and smoke alarms. Many portable electronic devices — such as laptops, smartphones and MP3 players will only accept rechargeable batteries. While other devices, including digital cameras and certain toys can use either rechargeable or traditional disposable batteries.
Primary Cell vs Secondary Cell: Key Differences
| Primary Cell | Secondary Cell |
| Primary cells are not reversible i.e. once they get discharge, they cannot be charged again. | Secondary cells are reversible and can be easily charged by electrical supply. |
| Irreversible reactions occur on it. | Reversible reaction occurs on it. |
| Primary cells can be used once. | Secondary cells can be used more than one time |
| Their internal resistance is very high. | They possess very low internal resistance. |
| There is no fluid in the cells hence it is also termed as dry cells. | They are made up of wet cells (filled and liquid cells) and molten salt (liquid cells with dissimilar composition) |
| It’s design is smaller and lighter | Its design is more complex and heavier. |
| Its initial cost is cheap. | Its initial cost is high. |
| They can be easily used. | In comparison to primary batteries they are difficult to handle. |
| They have relatively short lives. | They Have a long life. |
| They cannot be used as storage devices. | They may be used as energy storage devices. (E.g. solar thermal energy converted to chemical energy ) |
| It Functions only as galvanic cells. | It Function both as galvanic and electrolytic cells |
| Can be used as long as the material is active in their composition | Can be used again and again by recharging the cells. |
| Mostly used for intermediate work with low current rates. | Can be used for condition rating with heavy load currents. |
| Used in portable devices as they produce current immediately. | Needs to be charged before use and used in automobiles. |
| Have lower self discharge rate and can store power. | Have a higher self discharged rate compared to primary cells. |
| Example of primary battery : Daniel cell , Dry cells | Examples of secondary battery: lead-acid cells, Ni-Cd cells etc. |
What are the characteristics of disposable batteries?
The most common disposable battery is the alkaline and it has all of the standard sizes available for typical electronic devices. Standard sizes include AAA, AA, C, D, and the 9 volt as well as lantern batteries in 6 and 12 volt. Disposable batteries provide a great initial charge, which makes them the perfect battery for low voltage applications.
What are the characteristics of rechargeable batteries?
are nickel cadmium, nickel metal hydride, lithium or sealed lead acid. They come in a variety of sizes and voltages. They are often used for electronic devices that demand more power and regular battery replacement. They also guarantee extended battery life, which makes them the perfect battery for high-drain frequent-use applications.
Are there any dangers associated with rechargeable or disposable batteries?
Yes. Both rechargeable and disposable batteries contain toxic metals. Rechargeable batteries are less toxic than disposables, but they do still contain hazardous materials and must be handled with care. Rechargeable batteries are more prone to exploding or starting fires than disposable batteries, especially if they are exposed to dangerous conditions such as extreme temperatures, faulty connections or sparks. Consumers must take extra care to use both rechargeable and disposable batteries responsibly.
Key Takeaways
- Secondary cell last long and can be used over again and again
- A secondary cell is rechargeable meaning that the chemical reactions taking place in the cell are reversible and can be carried out in the opposite direction to charge the cell again.
- Whereas a primary cell cannot be recharged, the chemical reactions in it cannot be reversed.