Swollen LiPo battery

Overview

Swollen LiPo cell — stop using immediately.

DJI Intelligent Battery, LiPo/LiIon FPV packs, ISDT/Q6 charger, XT30/XT60.

Symptoms

Typical "Swollen LiPo battery" signs in flight, app or OSD:

• Pack pillow-shaped
• Hard to insert in drone slot
• Heat during charging
• Log cycle count and cell voltage after each flight.

Common causes

Before replacing parts, rule out software, mechanical and environmental causes:

• Overheating or over-discharge
• Physical impact
• Long storage at full charge
• Manufacturing defect

Tools needed

Prepare before diagnostics — saves time in the field:

• Multimeter
• LiPo storage bag
• Balance charger with cell readout

Step-by-step fix

Work safely: battery off when working on ESC/motors; props removed; after repair — VLOS test flight.

• DO NOT USE — fire and rupture risk.
• Store in LiPo bag; dispose via recycling or LiPo discharge.
• Replace pack; check if ESC drew excessive current.

Additional diagnostics

Log cycle count and cell voltage after each flight.

IR test on aged LiPo — uneven resistance = replace.

Cold battery — slower GPS and voltage sag.

When to contact service

If any of the following apply — do not fly and contact authorised service:

• Battery swollen, smells or smokes — dispose immediately.
• Cell below 2.5 V or short — do not charge.
• DJI BMS error after several attempts — use OEM battery.

Prevention

Prevention reduces failure risk and supports EASA Open / VLOS compliance:

• Storage 3.8 V
• Always use LiPo bag

Frequently asked questions

Is it safe to fly with "Swollen LiPo battery"?

No if the fault affects navigation, power, ESC or link. Fix on the ground first, then conduct a VLOS test flight in open area.

How long does diagnosis take?

Most “Swollen LiPo battery” cases — 15–45 min on the ground. Complex ones (firmware, hardware) may need 1–2 h and service.

How to safely dispose LiPo?

Discharge via resistor/salt water to 0 V, then recycling point. Never puncture or bin in household waste.