# Electrical – How to determine lithium battery versus the internal battery cells

batterieslithium

I have a Lithium Ion Polymer battery (EEMB LP963450) and I am trying to determine how many cells are in it, and something is not making sense with my math.

Here's the formula I am using:

Determine the number of cells in a Lithium Battery:

1. Battery Voltage Rating / Nominal Voltage Rating = # of cells in series
2. Battery Capacity / Nominal Capacity = # of cells in parallel
3. number of cells in series X # of cells in parallel = # of cells total

Here are the battery specs (at least what I have found):

• Battery Voltage Rating = 3.7 V (uncertain)
• Nominal Voltage Rating = 3.7 V
• Battery Capacity = 1800 mAh (uncertain)
• Nominal Capacity = 1800 mAh

Based on the numbers above, here's my math:

• 3.7 / 3.7 = 1
• 1800 / 1800 = 1
• 1 X 1 = 1 cell

So here's the problem.

With only one cell, this single-cell battery has 6.67WH ((mAh)*(V)/1000 = (Wh)) which is considerably over the 2.7WH per Lithium Ion cell for unlimited travel allowed on airplanes.

But this is a small battery so I am thinking I have something incorrect.

Maybe the Battery Voltage Rating and Capacity are not correct?

Maybe I'm plugging the numbers in wrong or not converting something I should be?

So my question is,

How do you determine how many cells are in a Lithium battery?

FYI Data

From EEMB:

Dear Phil, Thanks for your inquiry. This is Donna from EEMB, glad to
work with you.

For the model LP963450( 3.7V/1800mAh), it is a single cell, and your
following understanding is correct.

For the battery pack, it is consisting of the cells connected in
series or in parallel. If the battery stacked in series, the voltage
rating will be added multiply. If the battery satcked in parallel, the
capacity will be added in multiply. The following example is for your
ref.

1) model LP963450-2S ( 7.4V/ 1800mAh), 2 cells in series, the voltage

2)model LP963450-3P ( 3.7V/ 5400mAh), 3cells in parallel, the capacity

3)2LP963450-3 (7.4V/5400mAh), the battery stacked with 3 cells in
parallel , and then 2 battery pack in series , totally 6 cells

Hope it is clear. Any problems, please let me know. Have a nice day.

A great article on Lithium-polymer batteries:
The Basics of Lithium-Polymer Batteries

How do you determine how many cells are in a Lithium battery?
My assumption is for customer travel and the present limits are;

• MAX Lithium per cell 20Wh
• MAX Lithium per battery 100Wh

The battery in question. LP635940 Lithium Polymer Battery
3.7V @ 1.8Ah typ. capacity at 0.2C rate
= 6.66 Wh which is less than MAX per cell limit.

How many cells in package? Only 1.
Not because of capacity but because of construction method.

What are cells?
- discrete (separate) manufactured items.

How many items here?
1