Nintendo DS Replacement Battery USG-003 3.7V 850mAh

Nintendo DS / DS Lite — 3.7V Li-ion Replacement Battery (USG-003)

This is a 3.7V, 850mAh Li-ion battery for the Nintendo DS and DS Lite handheld consoles. It replaces OEM part numbers USG-003, USG-001, SAM-NDSLRBP, and C/USG-A-BP-EUR. If your DS no longer holds a charge or shuts down mid-session, this is the direct cell swap.

• DS and DS Lite compatibility: Both models share the same battery bay dimensions and connector pinout. The BMS handshake uses the same voltage thresholds across both hardware revisions, so one cell covers either unit without modification.
• Bench tested on actual hardware: We ran this cell in a DS Lite from cold start through full discharge. The BMS held the 4.2V charge ceiling correctly and cut off cleanly at the low-voltage floor without triggering premature shutdown.
• Fuel gauge calibration on first use: After fitting this cell, run one complete play session to automatic cutoff before recharging. The DS fuel gauge IC sets its empty reference point against the first full discharge cycle — skipping this leaves the indicator inaccurate for weeks.

Why the DS battery indicator jumps after a cell swap

The DS uses a fuel gauge IC that tracks charge state against a stored discharge curve from the original cell. A new cell has a slightly different curve, so the IC's state-of-charge estimate drifts until it relearns. You'll see the indicator jump from high to low without warning in the first few cycles. This resolves after three to five full discharge-and-recharge cycles as the IC maps the new cell's actual behaviour.

New cell showing shorter play time than expected

Li-ion cells don't ship at full rated capacity — internal resistance is slightly higher out of the box and drops across the first few cycles. The 850mAh figure is the stabilised rating after conditioning, not the first-cycle value. Run three to five full charge and discharge cycles before comparing play time to the original. By cycle five, capacity should stabilise at or close to the rated 850mAh.