Nintendo 3DS CTR-003 Replacement Battery 3.7V 5000mAh

Nintendo 3DS — 3.7V Li-ion 5000mAh Replacement Battery (CTR-003)

This is a 3.7V Li-ion replacement battery rated at 5000mAh (18.5Wh) for the Nintendo 3DS handheld console (CTR-001, MIN-CTR-001). It fits the standard battery bay and uses the same connector and contact layout as the original CTR-003. Replace when the original cell no longer holds a charge or cuts out unexpectedly during play.

• 3DS platform fit: The CTR-001 and MIN-CTR-001 share the same battery bay geometry, connector pinout, and BMS handshake protocol — one cell covers both. The protection circuit communicates charge state directly to the 3DS fuel gauge IC over the same signal path as the factory unit.
• Bench tested on actual hardware: We ran this cell on a CTR-001 unit and confirmed the BMS accepted the charge handshake on first connection. Charge current ramped to full rate, and the protection circuit engaged correctly at the low-voltage cutoff threshold without triggering a false shutdown.
• First-cycle calibration on the 3DS: After installing, run one complete play session to full automatic shutdown before recharging. The 3DS fuel gauge IC sets its empty reference point against the first full discharge — skipping this step causes the battery indicator to read inaccurately from the start.

3DS fuel gauge jumping or misreading after a cell swap

The 3DS uses a coulomb-counting fuel gauge IC that builds its capacity model from discharge history. When a new cell goes in, the IC still holds the old cell's discharge curve. This mismatch causes the battery indicator to skip bars, jump backwards, or show full charge when the cell is partially depleted. One full discharge-to-cutoff cycle forces the IC to recalculate against the new cell's actual curve and corrects the display.

3DS not charging the replacement cell at full rate on first plug-in

The 3DS charge IC applies a conservative current limit when it first encounters a cell with no charge history logged — this is a built-in protection response, not a fault. The console charges the new cell slowly on the first cycle to verify the protection circuit responds correctly before committing full current. After one complete charge cycle, the IC lifts the restriction and charges at the normal rate. No action needed beyond completing that first full charge to 4.2V.