Teltonika GH3000 BL-5C-H Replacement Battery 3.7V 1200mAh

Teltonika GH3000 Series — 3.7V Li-ion Replacement Battery (BL-5C-H)

This is a 3.7V, 1200mAh Li-ion cell built to the BL-5C-H specification. It fits the Teltonika GH3000, GH4000, and MH2000 mobile devices. Physical dimensions are 53.00 × 33.90 × 5.70mm — confirm against your original before installation.

• GH3000, GH4000, MH2000 compatibility: All three models share the same BL-5C-H form factor, connector pinout, and 3.7V nominal voltage rail. The BMS handshake on each device communicates with the same charge IC, so one cell covers the entire platform without modification.
• Bench tested on actual hardware: We ran this cell through full charge and discharge cycles on a GH3000 unit. The BMS accepted the cell on first connection, charge termination triggered correctly at 4.2V, and the protection circuit tripped as expected under simulated over-discharge conditions.
• Fuel gauge recalibration after swap: On first use, disable fast charging if available and run one complete discharge-to-charge cycle. This lets the fuel gauge IC map the new cell's discharge curve before high-current charging begins on an uncalibrated cell — preventing erratic percentage readings from the first charge.

Sudden shutdown at 20–30% on a fresh BL-5C-H cell

A new cell with an uncalibrated fuel gauge IC will cut out before the display reads zero. The coulomb counter in the GH3000 is still tracking the discharge curve of the old, degraded cell. When the new cell's actual voltage drops under modem or screen load, the device shuts off even though the OS reports charge remaining. One full discharge-charge cycle without interruption resets the reference curve and stops the premature cutoff.

Device not powering on after the BL-5C-H sat in storage

Li-ion cells stored uncharged can drop below 2.5V per cell, triggering a BMS lockout that blocks normal charging. The GH3000 will show no charge indicator and will not boot. Connect the device to a wall charger — not USB from a PC — for at least 20 minutes without pressing the power button. The charge IC on the motherboard will trickle current into the locked-out cell until it recovers to approximately 3.0V, at which point the BMS re-enables the charge path and normal charging resumes.