About this replacement
Custom Battery Pack 1ICP4/58/70 1S1P — 3.7V Li-ion Replacement Battery
This is a 3.7V Li-ion single-cell replacement pack rated at 2150mAh (7.96Wh), referencing OEM part number 1ICP4/58/70 1S1P. It matches the flat-cell format — 75.83 × 61.18 × 4.25mm — used in compact portable electronics where internal space is tightly constrained. Confirm your original pack carries this part number before ordering.
- Single-cell 1S1P configuration: One cell, no series stacking — the pack delivers a nominal 3.7V with a charge ceiling of 4.2V and a BMS cutoff floor around 2.75–3.0V. Any device expecting multi-cell voltage will reject this pack outright, so verify your original pack's spec label first.
- Bench tested on actual hardware: We cycled this pack through charge and discharge on a cell analyser. The BMS tripped correctly at the low-voltage cutoff and the pack accepted a full charge to 4.2V without thermal event or protection fault.
- First-cycle calibration: If your device shows a fuel gauge or percentage indicator, run one complete charge-to-discharge cycle immediately after fitting. Integrated fuel gauges lose calibration when cells are swapped and will misread capacity until they complete one full reference cycle against the new cells.
Pack not accepted by device after swap
Some devices run a voltage-range check or BMS handshake at power-on. If the pack ships at storage voltage — typically 3.6–3.8V — a device expecting a freshly charged cell at 4.1–4.2V may flag it as failed or incompatible. Charge the pack fully before inserting it for the first time. If the device still rejects it after a full charge, power-cycle the device with the pack seated to force a fresh handshake.
Pack not reaching full charge on the first cycle
On the first charge, the device's charge IC may apply a reduced current while it characterises the new cells — this is normal conditioning behaviour, not a fault. The pack may terminate early or show a lower-than-expected state of charge after the first session. Allow a second full charge cycle; by cycle two, the charge IC typically lifts the current limit and the pack reaches the full 4.2V termination point.