Batteries on Telephones, Laptops, etc.

Let's get the pedantic bit out of the way first:- a battery is combination of cells. The cell is the basic single unit, a combination of cells either in series, parallel or series/parallel then becomes a battery.

In the case of lead acid (LA) battery charging - a 2v LA (actually 2.2v) may be a single cell or a multiple of cells in parallel, a 12v LA (actually 12.8v) will be a combination of at least 6 x 2v cells in series but is more commonly a group of multiple cells connected in parallel and then in series with five other identical groups to increase the amp hour rating of the whole.

It's easy to charge LA cells in series because they have a self equalising voltage effect where any cell that reaches its full charge voltage before other cells in the group will simply produce gas, thus releasing energy until the other cells have caught up. They also tend to accept less and less charge current as their voltage rises which also limits overcharge possibilities in the short term. Simply increasing the voltage across the battery to enable a sufficient charging current to flow will achieve the same result in the same time frame as would a lower voltage across a single cell

Lithium based cells are different, they do not have the ability to self equalise, they also have a very sharp knee curve at the top end of their charge cycle which can allow them to go very quickly into an over-voltage condition whereupon they can easily self-destruct - often with catastrophic results.

They also have a very much lower internal resistance, so the current limiting effect seen in LA types is not evident in Lithium types, and so thermal runaway is a real danger. Cells charged in series present this concern and these type of batteries require special balancing circuits to prevent over-voltage on individual cells. Many smaller batteries just limit the charging voltage to a more manageable level that limits the danger.

Charging these type of cells in parallel - where the voltage is identical across every cell prevents this problem but the circuitry required to achieve a change from series to parallel, or even series/parallel to series for charging purposes, and then back again for use would be prohibitive.

Remember also that most of these devices remain usable whilst charging - this would not be possible if the cell configuration was changed for charging.

I would say that there are a great many batteries that employ the smaller interconnected battery technique. for example, here is a picture of a 9 volt battery and how it is constructed.

And here is a A23 battery which is a stack of button cell batteries.

From your posts and replies, it seems that you're trying to ummmmm make a battery charge faster?

You can charge any battery faster, however in doing so you're risking fire, explosion electrical shock because you will be applying a higher voltage or current to accomplish the task which is outside of the manufacturers recommended specifications. Also in doing so, you're shortening the rated lifespan of said battery. There are certain charging parameters for every rechargeable battery and the batteries have been tested to be safe at that charging rate.

Maybe if you detailed what you are specifically trying to accomplish, we may be able to assist!?!?

Believe it or not, you can charge batteries in series just as fast as charging them in parallel. Charging 5 batteries in series requires 5 times the voltage but the same current as charging one. Charging 5 batteries in parallel requires 5 times the current but the same voltage as charging one.

When charging a bank of batteries in series, some care needs to be taken that they are all equally charged. Ideally, each cell should get the same charge, but cells age differently.