HE345 Nokia 6 2nd Replacement Battery 3.85V 3000mAh

Nokia 6 2nd Generation — 3.85V Li-Polymer Replacement Battery (HE345 / HE353)

This 3.85V, 3000mAh (11.55Wh) Li-Polymer cell replaces the original battery in the Nokia 6 2nd generation (2018 model). It fits the TA-1054, TA-1089, and TA-1099 variants sold under the Nokia 6 2018 designation. Use it when the original cell no longer holds enough charge for a full day of calls, messaging, and app use.

• Nokia 6 (2018) platform fit: The Nokia 6 2nd generation uses a shared BMS connector and voltage rail across all regional variants. HE345 and HE353 are both OEM part numbers for this same cell slot — the connector pinout and BMS handshake protocol are identical across both part codes.
• Bench tested on actual hardware: We ran this cell through full charge and load cycles on the Nokia 6 2018 mainboard. The BMS accepted the cell without fault flags, voltage regulation stayed within spec across the charge curve, and the charge IC completed a full cycle without cutoff errors.
• First-cycle fast charge caution: After installation, disable fast charging and complete one full discharge-charge cycle at standard rate. This lets the fuel gauge IC map the new cell's discharge curve before the charge IC pushes higher current into an uncalibrated cell.

Sudden shutdown at 20–30% on the Nokia 6 2nd after a cell swap

This happens because the fuel gauge IC is still reading the discharge curve of the old, degraded cell. A new cell has a steeper voltage cliff at lower state-of-charge than a worn one. When the modem fires a high-draw burst — during a call or mobile data handshake — the new cell's terminal voltage drops briefly below the shutdown threshold the IC has stored. The fix is one complete discharge-charge cycle with fast charging off, which forces the coulomb counter to recalibrate against the actual cell chemistry.

Phone warm near the battery during the first few charges after replacement

A new Li-Polymer cell has higher internal impedance than a broken-in one. The charge IC on the Nokia 6 2018 applies the same current profile it used on the old cell, so more energy converts to heat across the higher-impedance new cell during the constant-current phase. This is normal for the first two to three cycles and reduces as impedance settles. If the phone stays hot past the bulk charge phase or shows above 41°C on a battery stats app, stop charging and check the connector seating — a misaligned connector increases contact resistance and compounds heating.