MIR Spirodoc LR0034 Replacement Battery 3.7V 1150mAh

MIR Spirodoc / Spirobank II Series — 3.7V Li-ion Replacement Battery (LR0034)

This is a 3.7V, 1150mAh Li-ion replacement battery for the MIR Spirodoc Spirometer and the Spirobank II Smart BLE and Basic Spirometer. It powers the device's electronic display, measurement sensors, and onboard data logging. OEM part numbers LR0034, MB983, PBT LR0034, and 970085 all cross to this cell.

• Spirodoc and Spirobank II platform fit: Both the Spirodoc and Spirobank II lines share the same 3.7V cell footprint, connector pinout, and BMS handshake protocol — the same replacement cell works across the entire MIR portable spirometer range without modification.
• Bench tested on actual hardware: We cycled this cell through charge-discharge on a Spirodoc unit and confirmed the BMS accepted the cell, completed its verification pass, and reported accurate state-of-charge on the display with no fault codes logged.
• Post-swap power-on sequence: After fitting this battery, let the device complete its full power-on self-test without interruption. Medical device BMS firmware runs a verification check at startup — cutting power mid-sequence flags a false battery fault that sticks until the next clean reboot.

Charge indicator not reaching 100% on the first charge after swap

The Spirodoc's charge IC applies a conservative current ceiling when it detects a new or previously discharged cell. On the first charge cycle, the device may display 95–98% and plateau there. This is the charge controller limiting input to protect cell integrity, not a fault. Run one full charge-discharge cycle and the IC recalibrates its endpoint — subsequent charges will reach 100% and hold.

Device will not power on after the replacement cell sat in storage

Li-ion cells self-discharge during storage, and the Spirodoc's BMS has a low-voltage lockout that blocks startup if cell voltage drops below approximately 3.0V. A cell that shipped or sat on a shelf for several months may arrive below this threshold. Connect the device to its charger for a minimum of 30 minutes before attempting to power on — this brings the cell above the BMS recovery floor and allows the startup sequence to proceed normally. If the charge LED does not light within five minutes of connecting, check the charging cable and port contacts first.