Difference Between Primary Cell and Secondary Cell (With Table)

Déjà vu of our eighth-grade physics classes, primary and secondary cells refer to different types of batteries or cells. Different types of cells exist, each suited to their purpose vary accordingly. They are electrochemical cells of a parallel combination. Primary cells and secondary cells yield chemical energy utilized to produce a sufficient response. 

Primary Cell vs Secondary Cell

The main difference between primary cell and secondary cell is that while primary cell can only be used a single time, secondary cell, on the other hand, can be used multiple times, depending on its ability and composition. This quality of the cells that say whether the cells could be used once or several times is seen as the major distinction in classifying primary and secondary cells. 

As the name states, primary cells can only be utilized a single time. This quality essentially means that a primary cell cannot be recharged for further use. Its chemical reaction is used up the time it is put to use. Due to this, the chemical reaction in primary cells cannot be reversed.

Secondary cells are yet another type of battery cell that differ due to their ability to be recharged after initial use. They are composed of wet cells and molten lava. Secondary cells are recharged after the initial discharge of energy. This disposition of energy allows their chemical charge to be reversed, unlike that of primary cells.

Comparison Table Between Primary Cell and Secondary Cell

Parameters of Comparison

Primary Cell

Secondary Cell

Energy conversion

The chemical energy in the primary cell is turned into electrical energy.

The chemical energy turns into electrical energy that gets turned into chemical energy again.

Current level

Exclusive to weak currents.

Supplies weak and high levels of current.

Recharge

A primary cell cannot be recharged.

Is capable of being recharged more than once.

Discharge 

Carries a slow discharge, by comparison.

Comparatively higher discharge.

Price

Less pricey

Expensive

What is a Primary Cell?

A primary cell is a battery typically used in situations that require lightweight energy disposition. These cells can be utilized just once. This quality renders them incapable of being recharged again for another use. 

The electrode reaction is complete upon its initial use, and the reaction thus created cannot be reversed.

The primary cells convert chemical energy into electrical energy for a brief period of time. They are praised for their internal resistance, and primary cells are highly tolerant. 

They possess a high density and can only supply weak current links. These cells do not contain fluids in their composition and hence are also known as dry cells.

Primary cells are galvanic cells with a small lifetime and are used in gadgets where the cells have to be frequently changed. Since the primary cells cannot be recharged for another use, they are discarded after achieving their potential.

Despite their limited use, primary cells continue to be a popular part of manufacturing several consumer durables.

They have a slower discharge and can be used easily and effectively. Primary cells are meant for one-time use; they are much cheaper than their counterparts. Therefore, this makes primary cells a popular choice when travelling.

With their simple and efficient design, primary cells are usually used to make smoke detectors, door openers in garages, Daniel cells, etc.

What is a Secondary Cell?

Secondary cell refers to a cell or a battery that can be recharged via electrical means after complete discharge of the energy. This quality makes secondary cells reusable, unlike that of primary cells. 

Secondary cells are recharged by conducting electric current through the opposite direction of the discharge; this renders the battery ready to be used again.

The secondary cell comprises wet cells and molten salt; therefore, they are not dry cells. 

They have a lower resistance internally. This ability makes secondary cells ideal for conducting current with a higher energy level. Secondary cells can also conduct weak energy through their circuit. 

During initial discharge, the chemical energy has to be converted into electrical energy, utilized for various purposes. Secondary cells have to be recharged after use. When recharged, the secondary cell converts the energy back into chemical energy used for further purposes.

The above phenomenon talks about the reversible chemical energy conversion that secondary cells are capable of.

Secondary cells are designed in a much more complex way to withstand the high and regular flow of current that secondary cells are subjected to.

Due to their prolonged lifetime, secondary batteries, also known as rechargeable batteries, are used in applications that demand a high drain.

Secondary cells are expensive when compared to primary cells. 

Main Differences Between Primary Cell and Secondary Cell

  1. Primary cells can be used only once, after which their chemical discharge is used up. Secondary cells have the option of being recharged electrically to enable further use.
  2. Primary cells show a slower discharge and have high-density energy. Secondary cells, in comparison, have a lower energy density. 
  3. Primary cells only support low currents, whereas its counterpart is capable of conducting different current levels.
  4. Primary cells are limited to one use, therefore, have a short lifetime. Secondary cells are used repeatedly and can be utilized for a longer period.
  5. Primary cells have a simple design and are cheap. Secondary cells possess a complicated design and have a higher price.

Conclusion

Used essentially in providing energy to appliances that require electrical energy for functioning, primary and secondary cells form two different types of batteries.

Primary cells are used for short-term use and found in consumer durables predicted to be used just once. Secondary cells have a longer lifetime and are found in high-working electrical appliances.

Primary cells cannot be recharged and have an irreversible chemical change. Secondary cells are made to be recharged and thus, undergo a reversal of chemical change every time it is recharged via electrical conduction.

Consumers can choose between primary or secondary cells depending on the product use.

References

  1. https://internal-journal.frontiersin.org/articles/10.3389/fpls.2012.00204/full
  2. https://link.springer.com/article/10.1007/BF01007699