About this replacement
JBL Flip 5 Eco / Flip 5 Ocean — 3.7V Li-ion Replacement Battery (SUN-INTE-152)
This 3.7V, 5200mAh Li-ion cell replaces the original battery in the JBL Flip 5 Eco and Flip 5 Ocean portable Bluetooth speakers. Both models use the same cell format, connector pinout, and BMS handshake. Swap it in when the original cell no longer holds a usable charge.
- Flip 5 Eco and Flip 5 Ocean compatibility: Both variants share the same PCB layout, battery bay dimensions, and charge management IC. The cell measures 71.60 × 38.45 × 20.00mm and connects via the same two-pin harness, so one part number covers both.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the Flip 5 platform. The BMS accepted the pack without fault flags, balanced correctly through USB-C PD input, and held stable voltage through high-volume amplifier draw.
- Flip 5 fuel gauge calibration: Let the speaker discharge below 20% at least once a month before recharging. Constant top-off charging — plugging in at 60% or higher every time — causes the onboard fuel gauge to drift. Once the gauge drifts, the speaker shuts off at an indicated 20–30% with charge still in the cell.
Audio distorting before the battery indicator reaches empty
The Flip 5 amplifier draws a sharp current spike at high volume. When the cell ages or a new cell is poorly conditioned, internal resistance rises and pack voltage sags under that spike. The amplifier hits its minimum supply voltage and clips the audio signal before the fuel gauge shows low. On a fresh, conditioned cell, pack voltage should hold above 3.5V under full amplifier load — if it's dropping below that, check the cell's internal resistance or re-condition through a full discharge cycle first.
Speaker won't wake from USB-C when battery is deeply discharged
If the Flip 5 has sat unused for several months, the cell can drop below the minimum voltage threshold the USB-C PD controller will accept — typically around 2.5V. At that point, the charger sees the pack as a fault condition and won't initiate a charge session. Connect the speaker to a 5V USB-A source instead of USB-C PD; the lower-current trickle from a basic 5V port can recover the cell slowly without triggering the PD fault cutoff. Once the cell climbs above 3.0V, standard USB-C charging resumes normally.