# Calculating Lithium ion battery capacity in AH

When we talk about lithium battery, it means it built up using small other blocks called cells. As every battery have some capacity, these lithium too have capacity.

When we say *lithium battery 28ah or 30ah*, we talk about the battery capacity here.

Let’s break into it.

**For example 1 : **

If I am using a ** cell of 3.2V and 2800mAH **and connected 10 of these

*cells in parallel*as shown bellow. Here the capacity of this pack is given by :

Capacity of pack = Number of cells in parallel * Ah of single cell

i.e. = 10 * 2800mAh = 28000mAh

The capacity of the cells is added up or becomes the times of the number of cells in parallel. Whereas the voltage will remain same as 3.2V because voltage remains same in parallel.

**For example 2 : **

If I am using a cell of **3.2V** and **3000mAH** and connected 10 of these * cells in parallel *as shown above. Here the capacity of this pack is given by :

Capacity of pack = Number of cells in parallel * Ah of single cell

i.e. = 10 * 3000mAh = 30000mAh

Hence in this case the capacity of the pack will be greater than in example 1. We can conclude that it is the difference of battery capacity if we consider *lithium battery 28ah 30ah difference.*

## Working hours of a battery :

Let us understand this considering above example only.

**In example 1**, capacity is 28ah.

If we draw 1 ampere of continues current from this battery, calculating as following :

(want to know how to read current of battery using multimeter, click here)

Time = Capacity in ah / current drawn from battery in ampere

= 28ah/1a = 28 h

That means this battery will give you back up of 28 hours of continues use of 1 ampere.

**In example 2**, capacity is 30ah.

If we draw 1 ampere of continues current from this battery, calculating

Time = Capacity in ah / current drawn from battery in ampere

= 30ah/1a = 30 h

That means this battery will give you back up of 30 hours of continues use of 1 ampere.

Yes of course 2 hours more backup than 28ah battery.

Let me know if you want to know more about lithium ion 2wheeler and 3wheeler batteries.