About this replacement
Nintendo 3DS / CTR-001 — 3.7V Li-ion Replacement Battery (CTR-003)
This is a 3.7V, 1300mAh Li-ion cell built to fit the Nintendo 3DS handheld console. It slots into the CTR-001, MIN-CTR-001, and 2DS XL chassis using the original OEM part number CTR-003. When your original cell no longer holds a charge through a play session, this is a direct cell swap.
- 3DS family fit: The CTR-001, MIN-CTR-001, and 2DS XL all share the same 3.7V battery bay and connector pinout. The BMS expects the same charge termination voltage across the lineup, so one cell covers all listed models without modification.
- Bench tested on actual hardware: We cycled this cell in a CTR-001 unit and confirmed the charge IC accepted the new cell, BMS handshake completed without error flags, and the console reached full charge termination voltage at 4.2V.
- Fuel gauge reset after installation: Run one full play session to automatic low-battery cutoff before recharging. The 3DS fuel gauge IC calibrates its empty reference point against the first full discharge cycle. Skipping this step causes the battery indicator to read inaccurately from day one.
Why the 3DS fuel gauge jumps or shows wrong levels after a cell swap
The 3DS uses a coulomb-counting fuel gauge IC that tracks capacity against a stored discharge curve from the previous cell. A new cell has a different internal resistance profile, so the IC's stored reference no longer matches what it measures. This causes percentage jumps, sudden drops, or a stuck reading. After two to three full discharge and recharge cycles, the IC re-maps to the new cell's curve and the gauge stabilises.
New cell plays for noticeably less time than the old battery did at full charge
Li-ion cells ship in a partial state of charge and need conditioning cycles before reaching rated capacity. A new CTR-003 cell typically delivers below its 1300mAh rated output for the first three to five charge cycles. The charge IC may also apply a conservative current limit on an unrecognised cell during the first charge. Run three complete charge and discharge cycles, then check whether playtime improves — most cells reach rated capacity by cycle five.