How Inogen battery rebuilding works, step by step

The rebuild in six steps

1. Diagnostics. We check the cells, the BMS (battery management system), the temperature sensor and all connections to find out exactly what is worn or faulty.
2. Repairs if needed. If the BMS, thermistor or connections need repair, we do it. This is included in the price.
3. New cell pack. The full cell pack is replaced with new 18650 Li-ion cells from Samsung, LG or Sanyo. We replace all cells, not just some of them.
4. Spot welding. The cells are joined by spot welding with 0.2 mm nickel strip and fitted into the original Inogen housing.
5. BMS programming. The cycle counter is reset and the charge indicator is calibrated to the new cells, so the indicator matches the real charge.
6. Final test. Before shipping, every battery is tested for capacity, voltage stability and temperature.

Why all cells are replaced

In general, a Li-ion pack is only as good as its weakest cells. Mixing new cells with old, worn ones would leave the battery limited by the aged cells. That is why we replace the complete cell pack in every rebuild.

Because the original electronics and connectors are kept, the battery fits your concentrator as before and works with your original Inogen charger.

How long does it take?

The rebuild takes 2–5 business days from the day we receive your battery. Add shipping time in both directions. If you depend on the battery, plan ahead.

If you depend on continuous oxygen, keep a backup source (a spare battery, a stationary concentrator or a cylinder) while your battery is away. For any questions about your therapy, ask your doctor or oxygen supplier.

How to order

1. Fill in the order form on our website: choose your battery model and the return shipping method.
2. Pay securely via Stripe.
3. Pack the battery as described below and send it to: Axis Baterie, Strzeszyńska 30B, 60-479 Poznań, Poland.
4. We rebuild, test and return it. Return shipping is by InPost parcel locker in Poland or by courier.

Prices: €60 for a standard 8-cell pack (G2, G3, G4) and €130 for an extended 16-cell pack (G2, G3, G5). See Inogen battery rebuild cost for what is included.

How to pack and ship the battery safely

Lithium-ion batteries need careful packing:

• Protect the terminals against short circuit, for example with tape over the contacts or in a separate bag.
• Use a sturdy box with enough padding so the battery cannot move or be crushed.
• Send only the battery unless we have agreed otherwise. You do not need to send the charger or the concentrator.
• Add a note with your name, order details and a short description of the problem.
• Check your carrier's rules for shipping lithium-ion batteries before sending.

Do not ship a damaged battery. If your battery is swollen, cracked, leaking, smells burnt or gets very hot, stop using it, do not open it and contact us first by e-mail at sklep@axis-baterie.pl.

What if you decide not to proceed?

If after diagnostics you decide not to go ahead with the rebuild, we either return the battery at your cost or dispose of it free of charge, as you prefer.

After the rebuild

You receive your battery with a 12-month written warranty. Charge it fully with your original charger before first use. To keep it in good condition for longer, follow our tips on how to extend Inogen battery life.

Please note: Axis Batteries is an independent service, not affiliated with Inogen, Inc. A rebuilt battery is not an original Inogen product and the manufacturer's battery warranty does not apply to it. If your concentrator is rented or provided by a supplier or insurer, ask them before sending the battery.

Start your Inogen battery rebuild →