About this replacement
BCI SpectrO2 Series — 7.4V Li-ion Replacement Battery (DI5070)
This 7.4V 3400mAh Li-ion battery replaces part number DI5070 and WW1090 in BCI SpectrO2 pulse oximeters. It fits the SpectrO2 10, SpectrO2 20, and SpectrO2 30 clinical and home pulse oximetry devices. These monitors measure blood oxygen saturation and heart rate, so battery continuity directly affects patient monitoring capability.
- SpectrO2 10 / 20 / 30 compatibility: All three models run the same 7.4V power rail with an identical connector and BMS handshake protocol, which is why they share one battery SKU across the range.
- Bench tested on actual hardware: We cycled this cell through the SpectrO2 charge-discharge sequence and confirmed the BMS accepted the cell, completed charge termination correctly, and held voltage within spec under oximetry load.
- Power-on self-test after swap: After fitting this battery, let the device complete its full startup self-test without interruption. The BMS runs a verification sequence at boot — cutting power mid-sequence flags a false battery fault that persists until the next clean reboot.
Device not completing boot sequence after battery swap
The SpectrO2 BMS runs a cell-verification routine during power-on that checks voltage stability before the device enters normal operating mode. A new cell that has partially self-discharged during storage may sit just above the BMS recovery threshold, causing the boot to stall or loop. Plug the device into the charger before the first power-on and bring the cell to a full charge. Once fully charged, the boot sequence completes normally and the device enters standard operating mode.
Charge indicator not reaching 100% on the first charge
On the first charge cycle, the SpectrO2 charge IC applies a conservative current limit to a new cell it has not previously profiled. This means the indicator may stall at 95–99% for an extended period before terminating. This is normal charge IC behaviour, not a faulty cell. Run one complete charge-discharge cycle and the charge IC recalibrates its termination threshold to the actual cell capacity.