Cattron Theimeg BT904-00044 Replacement Battery 6V 2100mAh

Cattron Theimeg TH-GA Series — 6V Ni-MH Replacement Battery (BT904-00044)

This is a 6V, 2100mAh Ni-MH replacement battery for the Cattron Theimeg TH-GA crane remote control system. It fits the TH-GA, TH-GA/NC-10, and TH-20DS-S/E wireless remote units used in industrial crane and hoist applications. OEM part number BT904-00044.

• TH-GA platform compatibility: The TH-GA, TH-GA/NC-10, and TH-20DS-S/E share the same 6V battery bay, connector pinout, and charge circuit. All three units accept this cell pack without modification to the housing or charging contacts.
• Bench tested on actual hardware: We cycled this pack through full charge and discharge on the TH-GA platform. The BMS held stable voltage across solenoid activation events, and the charge circuit accepted the cell correctly without false fault flags.
• Monthly charge cycle for infrequent crane remote use: Crane remotes often sit idle for weeks between shifts. Ni-MH cells lose charge during storage — if the pack drops too low, the remote will not power on. Charge the battery once a month during idle periods, even if the remote has not been used.

Solenoid activation causing power dropout on the TH-GA

When a crane solenoid or relay fires, it draws a short inrush current spike through the remote's power circuit. A degraded or deeply discharged battery cannot sustain that spike — voltage sags below the BMS cutoff threshold and the remote drops out. This is not a remote fault. A fully charged, correctly rated 2100mAh pack at 6V handles the inrush without voltage sag. If dropout persists after a full charge cycle, check the battery contacts for corrosion and clean them before ruling out the cell.

TH-GA remote showing low battery immediately after fitting a new cell

Ni-MH cells ship at storage voltage — typically well below a full charge state. The TH-GA reads this low resting voltage and flags it as a depleted battery even though the cell is new. This is not a faulty battery. Connect the remote to its charger before first use and allow a full charge cycle to complete. Once the cell reaches its rated 6V charge state, the low-battery indicator will clear.