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05-30-2017 | 04:28 PM

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Lipos

[QUOTE=Direwolf;2526357]This'd be a good time to dust off a physics text book if you have one handy. But, here's what you need to know...

A battery is a group of cells.
A cell has a capacity, measured in Amp*Hours (pronounced "Amp Hours" ), abbreviated as "Ah".
A cell has a certain amount of potential to do work, measured in Volts, abbreviated as "V".

When you put cells in series, their voltage is added together. For example:

Code:

-----&gt; [- 3.7V +] [- 3.7V +] [- 3.7V +] -----&gt;

This battery has 3 cells in series, so this is called a "3S" battery. The total voltage of this battery is 3*3.7V = 11.1V.

When you put cells in parallel, their capacity is added together. For example:

Code:

.--&gt; [- 1.2Ah +] --.
--- --&gt; [- 1.2Ah +] -- ---&gt;
'--&gt; [- 1.2Ah +] --'

This battery has 3 cells in parallel, so this is called a "3P" battery. The total capacitance of this battery is 3*1.2Ah = 3.6Ah.

You can use combinations of cells in series and in parallel to achieve different levels of Voltage and Capacitance. For example:

Code:

.--&gt; [- 1.2Ah, 3.7V +] [- 1.2Ah, 3.7V +] [- 1.2Ah, 3.7V +] [- 1.2Ah, 3.7V +]--.
--- --&gt; [- 1.2Ah, 3.7V +] [- 1.2Ah, 3.7V +] [- 1.2Ah, 3.7V +] [- 1.2Ah, 3.7V +]-- ---&gt;
'--&gt; [- 1.2Ah, 3.7V +] [- 1.2Ah, 3.7V +] [- 1.2Ah, 3.7V +] [- 1.2Ah, 3.7V +]--'

Direwolf I made a Lipo pack of 6 5s [ 3 in series then parellel with 3 more in series] but it turned out it was to much for my BBSHD/electric bike.
I was told I need a 14s pack so since I already have 5s I'm thinking on using 4 of them + 2 4s to make my 14s pack BUT I would like to know if what I'm planning is possible. I'm thinking on making a pack as fallow- (keep in mind they are all of the same mah & c rating) 2 5s in parallel + 2 5s in parellel + 2 4s in parellel than connect the three parellel packs into series hoping to make a 14s pack of 51.8 v @3.7per cell / 58.8v "hot of the chart". I HOPE THIS MADE SENSE. Please anyone let me know if I can do this????? THX.

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