What Are Cells in a Laptop Battery?

In summary, the number of cells in a battery determines its voltage, and having more cells can provide a longer battery life. However, this may not be the case for different laptops as the cells may be different. When comparing batteries with the same charge capacity, a 12-cell battery may last longer than a 9-cell battery.
  • #1
swraman
167
0
Hi,

Im looking for a new laptop battery.

Something that's confusing me is the number of cells in a battery; what is a cell? is it a smaller battery that exists in the larger battery?

If so, are the cells connected in series whose voltage sums to the voltage of the total battery?
Or are the "cells" connected in parallel...for reasons I can only guess at?

Also, and more to the point I am trying to figure out: I know laptop batteries are rated in mAh, how much charge it can hold. But would it be better to get a 12 cell battery or a 9 cell battery, both with the same charge capacity?

My intuition would be that fewer cells would be better because the lifetime of the battery will be longer: Since the internal resistance of the battery builds up in each cell, there will be less internal resistance if there are fewer cells (since they are in series).

Here I am assuming that all the cells, whether they are in a 9 or 12 cell battery, develop internal resistance at the same rate; which I don't know if is true.

Thanks for any help
Raman
 
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  • #2
A fully charged lithium bettery cell has a voltage of about 4.2 volts. The bigger the area of the cell, the more amps it can provide. Put 3 cells in series and you have a 12-volt battery. Put 3 cells in parallel, and you have a 4 volt battery that can deliver the same current 3 times longer.
 
  • #3
In other words - if you have a choice of batteries for the same laptop the battery life will be proportional to the number of cells. A 12cell will last 1/3 longer than a 9 cell

This isn't necessarily true between different laptops - the cells might be different.
 
  • #4
mgb_phys said:
In other words - if you have a choice of batteries for the same laptop the battery life will be proportional to the number of cells. A 12cell will last 1/3 longer than a 9 cell

This isn't necessarily true between different laptops - the cells might be different.

Will this be the case even if the 12cell and the 9cell have the same charge capacity? The 2 I am looking at both can hold 7200mAh, but one is 9cell and one is 12cell.
 

Related to What Are Cells in a Laptop Battery?

1. What exactly are cells in a laptop battery?

Cells in a laptop battery are small, cylindrical containers that store electrical energy. They are typically made of lithium-ion or lithium-polymer and contain electrodes, electrolytes, and a separator to prevent short circuits.

2. How do cells work in a laptop battery?

Cells work by converting chemical energy into electrical energy. When the battery is charged, the lithium ions move from the positive electrode (cathode) to the negative electrode (anode) through the electrolyte. When the battery is in use, the ions move back to the cathode, creating a flow of electrons and generating electricity.

3. How many cells are typically in a laptop battery?

The number of cells in a laptop battery varies depending on the size and capacity of the battery. Most laptop batteries have 3-6 cells, but some high-performance laptops may have up to 12 cells. The more cells a battery has, the longer it can hold a charge.

4. What factors affect the lifespan of cells in a laptop battery?

The lifespan of cells in a laptop battery can be affected by various factors, including the number of charge cycles, temperature, and usage patterns. Lithium-ion batteries gradually lose their capacity over time, and extreme temperatures can also decrease their lifespan. Recharging the battery before it is fully drained can also help prolong its lifespan.

5. Can the cells in a laptop battery be replaced?

Yes, the cells in a laptop battery can be replaced. However, it is not recommended to do so unless you have experience working with electronics and the proper tools. It is usually more cost-effective to replace the entire battery rather than just the cells. If your battery is no longer holding a charge, it may be time to replace it with a new one.

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