AirSep FreeStyle Internal Battery

AirSep FreeStyle Internal Battery

Model: BT018-1S, BT021-1S
For Reference Only
Power Option:

AirSep Internal Battery

This is the Internal Battery for the AirSep Freestyle 3 and AirSep Freestyle 5 Oxygen Concentrators. The battery is lightweight, durable, and transportable.

AirSep Freestyle 3

The AirSep Freestyle 3 Portable Oxygen Concentrator is a lightweight device weighing less than five pounds. The Freestyle is perfect for the on-the-go oxygen concentrator. It's an FAA approved device with multiple charging options and three different operational modes.

Note: BT018-1S replaces BT015-1 internal battery.

AirSep Freestyle 5

The Internal Battery also works with the AirSep Freestyle 5 Portable Oxygen Concentrator. That device has five different operational modes, and like the Freestyle 3, offers several charging options in one convenient and travel friendly package.

Key Features

  • Lightweight and Portable
  • Compatible with AirSep's Freestyle 3 and 5 Oxygen Concentrators
  • Will Power Your Concentrator

Reviewers Tip:

When you travel with an oxygen concentrator, be sure to carry it on the plane with you. Packing your equipment leaves it susceptible to unnecessary damage.

How to change internal battery:

Before you begin, use an ESD Mat

1.           Remove Unit from Case

2.           Remove front 3 screws

3.           Remove front cover

4.           Remove 2-pin & 8-pin connections

5.           Remove battery

6.           Install new battery

7.           Reconnect 2-pin & 8-pin connections

8.           Replace front cover


Is this battery compatible with other AirSep devices?

This battery is intended for use with the Freestyle 3 only.

Is this a CPAP product?

It is not. It is intended for use with oxygen concentrators.





Return on warranty issues only.


Technical Data
BT018-1S, BT021-1S
Machine Weight
.76 lbs (344.7 g)
Machine Size Only
.75 H x 2.0 W x 5.38 L inches (1.9 x 5.1 x 13.7 cm)
4.0 Ahr, 59.2 Whr
Lithium Ion, 14.8 volts (nominal)
Battery Warranty
30 days
Item Includes
One selected Internal battery.

AirSep 3 - BT018-1S
     The battery comes in a box with outside labeled with battery transport information: UN3480
      UN3480 Lithium-Ion Batteries - Dangerous Goods 
Image result for un3480
      Battery, assembly, pack, Lithium ion, 4S2P*, 8-cell, internal, FS, service
      Serial Number (SN)
      *  4 cells in a series, 2 cells in parallel
S = in series: add the cell voltages
          YP = in parallel: add the capacity.)

AirSep 5 - BT021-1S

       Battery, Assembly, Pack, Lithium Ion, 4S2P, 8-cell, Internal, F5, Service.
       Serial Number (SN)

Image result for UN3480
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