1ICP/8/34/50 1S1P Replacement Battery 3.7V 1500mAh

Custom Battery Pack 1ICP/8/34/50 1S1P — 3.7V Li-ion Replacement Battery

This is a 3.7V 1500mAh (5.55Wh) Li-ion replacement for the OEM pack carrying part number 1ICP/8/34/50 1S1P. The 1S1P configuration means a single cell, no series or parallel stacking. It measures 50.40 × 36.52 × 8.34 mm — check those dimensions against your housing before ordering.

• 1S1P single-cell format: One cell, one voltage rail at 3.7V nominal. Devices spec'd for this pack rely on that single-cell BMS handshake — the protection circuit handles overcharge cutoff, over-discharge cutoff, and short-circuit response without a multi-cell balancing stage.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on the bench, confirming the protection IC trips at the correct cutoff voltages and that the cell holds capacity within spec across the first three cycles.
• First-cycle calibration: If your device has an integrated fuel gauge, run one complete charge-discharge cycle after swapping this pack in. Fuel gauge ICs track coulomb counting against the old cell's baseline — one full cycle resets that reference to the new cell's actual capacity.

Pack running at lower voltage than rated on first use

Li-ion cells ship at storage voltage — typically 3.6V to 3.85V, intentionally below full charge. That's not a defect; it's how cells are stored safely during transit. Your device may read low capacity or behave erratically if it checks cell voltage at boot. Charge the pack fully before first use. A full charge brings the cell to approximately 4.2V, which is where rated capacity and stable BMS behaviour begin.

Pack not reaching full charge on the first cycle

On the first charge cycle, some charge ICs apply a reduced current to new cells — particularly if the cell voltage came in below the IC's pre-charge threshold. This can make the first charge terminate earlier than expected or report a lower fill level. It typically clears on the second full charge cycle once the IC has characterised the cell's internal resistance. If the issue persists past two cycles, verify the charger output voltage matches the pack's 4.2V maximum charge voltage.