Pantech IM-100 BA-8300E Replacement Battery 3.85V 2900mAh

Pantech IM-100 Series — 3.85V Li-Polymer Replacement Battery (BA-8300E)

This is a 3.85V, 2900mAh lithium-polymer replacement battery for the Pantech IM-100, IM-100K, and IM-100S smartphones. It replaces OEM part number BA-8300E and restores power to phones where the original cell has degraded or failed entirely. Capacity is 11.17Wh at the rated voltage.

• IM-100 series compatibility: The IM-100, IM-100K, and IM-100S share the same battery bay dimensions and connector pinout, so a single BA-8300E cell covers all three variants. The BMS handshake protocol and charge IC voltage thresholds are identical across the series.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on an IM-100 unit. The BMS accepted the standard charge profile without tripping cutoff, and the fuel gauge IC tracked state-of-charge correctly after one full conditioning cycle.
• Fuel gauge recalibration on first install: After fitting this battery, disable fast charging for the first complete discharge-charge cycle. The fuel gauge IC is still calibrated to the old cell's discharge curve — running one full cycle at standard current lets it re-anchor the coulomb counter before high-current charging begins.

Sudden shutdown at 20–30% on the IM-100 after a cell swap

A new lithium-polymer cell has a steeper voltage discharge curve than a worn original. When the modem transmits or the screen peaks in brightness, instantaneous current draw can drag cell voltage below the BMS cutoff threshold — even while the fuel gauge still reads 20–30%. This is not a defective battery. The fuel gauge IC is working from stale data mapped to the old cell. One full discharge down to automatic cutoff, followed by a full charge with fast charging disabled, resets the coulomb counter and eliminates most premature shutdowns.

Phone feels warm near the battery during the first few charges

A fresh high-impedance cell dissipates more energy as heat during the initial charge cycles than a broken-in one. The charge IC on the IM-100 is pushing current into a cell that hasn't yet settled its internal resistance — this is normal for the first two to three cycles. Warmth should reduce noticeably by the third full charge. If the phone remains hot to the touch beyond cycle three, check that the replacement cell is seated flat with no air gap behind the battery cover, as poor contact increases localized resistance.