The battery is an important component of the laptop. It gives the laptop the power of mobility. The efficiency and performance of the laptop greatly depends on the battery when the laptop is not connected to a power outlet. The improved power and increased backup time of laptop batteries is one of the main reasons for the growing popularity of laptops. The modern laptop batteries are far more advanced than their early predecessors.
Laptop batteries have come a long way since their inception. Older laptop batteries were quite heavy and did not provide good backup time.
History of Laptop Batteries:
- AA Batteries:
You will be surprised to know that older laptops used to run on AA batteries. Many AA batteries were required to run a laptop, and though there were many AA batteries fitted in the laptop, they did not have a long life. The number of AA cells also increased the weight of the laptop. Running a laptop on AA batteries was quite an expensive proposition, and the batteries needed to be changed frequently. The use of AA batteries was also not good for the environment. The discarded AA batteries contained harmful chemicals and only added to environmental waste.
- Lead-Acid Cell:
In the late 80s, laptops ran on heavy lead acid batteries. These batteries made the laptop very heavy and did not provide any good backup time. The lead-acid cell, however, was the first rechargeable battery to be invented.
Gaston Plante invented the lead -acid cell. It was the first battery that could be recharged by passing a reverse current through it. The lead-acid cell consisted of a lead anode and lead dioxide cathode, and both were immersed in sulphuric acid. Both electrodes of the lead-acid cell reacted with sulphuric acid to produce lead sulfate.
The reaction caused the lead anode to release electrons, while the reaction at the lead dioxide end consumed the electrons, causing a flow of electric current. The chemical reaction within the cell was reversed by passing a reverse current through it, which was equivalent to recharging the lead-acid cell.
Though these batteries were heavy, they had a considerable capacity to hold electrical charge. The Macintosh portable was powered by a sealed lead-acid cell battery. However, lead acid batteries were soon discarded when nickel cadmium batteries were invented.
- Nickel Cadmium battery:
The invention of the NiCad battery was a boon for the development of laptop devices. The sealed NiCad cells could be assembled into battery packs. These batteries had a very low internal resistance and could supply high surge currents. This characteristic of the batteries made them more popular and the preferred battery cells of laptop manufacturers.
However, one of the greatest disadvantages of NiCad batteries was their ‘memory effect’. These batteries needed to be drained completely before recharging. The efficiency of these batteries greatly decreased if the batteries were recharged without completely discharging. The development moved on at a snail’s pace after the invention of Nickel metal hydride batteries.
- Nickel Metal Hydride batteries:
Nickel metal hydride batteries offered superior capacity, but they too suffered from the memory effect. These batteries offered 2-3 times more capacity than NiCad batteries. There was no noticeable development in battery technology after the arrival of Nickel Metal Hydride batteries. The NiCad and the NiMH remained the preferred batteries in laptops manufactured the world over for a long time. These batteries can be even found today in older laptops. The improvement in the fuel cell technology paved the way for the invention of Lithium Ion batteries.
- Lithium Ion batteries:
Invented in the 1970s, Lithium Ion batteries are the preferred batteries in modern laptops. These batteries do not suffer from the memory effect. The arrival of Li-Ion batteries have proved to be a blessing for laptop manufacturers as they can now make more slimmer and lighter machines that work for hours on these batteries. Li-Ion batteries have the highest energy densities among all types of rechargeable batteries. They are also known to have the slowest loss of charge when not in use. However, these batteries lose their efficiency when exposed to high temperatures.
- Lithium Polymer batteries:
The Lithium Polymer battery is considered to be the next-gen laptop battery. These are new types of rechargeable batteries used in laptops. They can be safely stored for around 2-3 months without the risk of losing their charge. Battery manufacturers claim that these batteries have the highest electrical density, which makes them ideal for laptops.
The laptop battery has come a long way since its invention. Today, you can find 6 cell or 9 cell laptop batteries that can run your laptop for hours on a single recharge. Besides, you need not wait to discharge these batteries completely before recharging them. You can keep these batteries 100% charged all the time, which ensures that they are fully loaded when you are ready to go mobile.