About this replacement
Sonos Roam — 3.7V Li-ion Replacement Battery (111-00005)
This is a 3.7V, 5200mAh Li-ion battery for the Sonos Roam portable speaker. It fits the Roam directly and matches the OEM part numbers 111-00005 and IP-038535-101. When the original cell degrades after hundreds of charge cycles, this replacement restores full wireless and Bluetooth audio functionality without replacing the speaker.
- Sonos Roam fit: The Roam uses a single-cell Li-ion pack at 3.7V nominal. The BMS in the Roam monitors cell voltage and communicates charge state to the firmware. This replacement matches that voltage rail and connector so the fuel gauge reads accurately from the first charge cycle.
- Bench tested on actual hardware: We cycled this cell through charge and discharge on the Roam platform. The BMS accepted the pack without fault codes, charge termination triggered correctly at 4.2V, and low-voltage cutoff engaged at the expected floor — no false low-battery shutdowns during testing.
- Fuel gauge reset after install: After fitting this battery, drain the Roam completely until it powers off, then charge it uninterrupted to 100% before use. This calibrates the fuel gauge to the new cell's actual capacity and prevents the charge indicator from reporting inaccurate levels.
Capacity fade from constant top-off charging on the Roam
The Roam is frequently left on a charging surface or USB-C cable between uses, which means the cell spends long stretches near 100% charge. Li-ion cells degrade faster when held at high state-of-charge — the elevated voltage stresses the cathode chemistry over time. This pattern causes measurable capacity loss within 12–18 months on original packs. Once the new battery is installed, let the speaker discharge below 20% at least once a month before recharging to slow this degradation cycle.
Audio distorting before the battery indicator reaches empty
As the Li-ion cell ages and internal resistance rises, voltage sags sharply when the amplifier draws peak current — particularly at higher volume levels. The amp clips before the fuel gauge shows critical because the voltage drop is transient, not a steady low reading the BMS logs. The result is audible distortion or crackle while the indicator still shows one or two bars. Fitting a fresh cell with lower internal resistance resolves the sag — confirm the speaker plays cleanly at full volume with the battery reading above 3.6V under load.