About this replacement
Divoom Timebox Evo — 3.7V Li-ion Replacement Battery (INR18650)
This is a 3.7V, 2600mAh (9.62Wh) Li-ion INR18650 cell for the Divoom Timebox Evo portable Bluetooth speaker. It powers both the audio amplifier and the LED pixel display simultaneously. Fits the Timebox Evo directly — confirm your unit takes a single 18650 cell before ordering.
- Timebox Evo power rail: The Evo runs its amplifier, Bluetooth radio, and LED matrix from a single 18650 cell at 3.7V nominal. All three loads share that rail simultaneously, so the cell sees combined current draw during high-volume playback with animations active.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles while monitoring the protection circuit. The BMS responded correctly to overdischarge cutoff and resumed charging without manual reset on each test cycle.
- Monthly full-discharge cycle: The Timebox Evo is commonly used as a desk speaker and topped off before it drops below 50%. Discharge the cell below 20% at least once a month before recharging — without it, the fuel gauge drifts and the display reports false charge levels within a few months.
Why the Timebox Evo audio distorts before the battery indicator reaches empty
As the INR18650 cell discharges, internal resistance rises and cell voltage sags under amplifier load. At high volume, the amplifier demands peak current that the weakened cell cannot deliver without dropping voltage below the amplifier's stable operating threshold. The amplifier clips the output signal to compensate — you hear distortion while the display still shows charge remaining. This happens earlier as the cell ages. A new cell with lower internal resistance eliminates the sag and pushes the clipping point back toward actual empty.
Timebox Evo won't wake from USB after sitting unused for weeks
A deeply discharged INR18650 cell can drop below the USB charging controller's minimum acceptance voltage — typically around 2.5V. Below that threshold, the charger circuit sees the cell as absent or faulty and refuses to initiate a charge cycle. Plugging into USB appears to do nothing. To recover, use a dedicated Li-ion cell charger that supports a trickle or recovery mode to bring the cell back above 2.8V, then return it to the Evo for normal USB charging.