Canon NB-4L Digital IXUS Replacement Battery 3.7V 850mAh

Canon Digital IXUS 100 IS / 110 IS / 120 IS — 3.7V Li-ion Replacement Battery (NB-4L)

This is a 3.7V, 850mAh Li-ion replacement cell for the Canon NB-4L battery pack. It fits the Digital IXUS 100 IS, 110 IS, 120 IS, IXUS 30, and over 50 additional Canon compact camera bodies that share the NB-4L form factor. Dimensions are 40.40 × 35.40 × 5.90mm — a direct physical match for the OEM battery bay.

• IXUS 100 IS / 110 IS / 120 IS platform fit: These three IXUS generations share the same NB-4L voltage rail, connector pinout, and battery compartment dimensions. Swapping between models in this group carries no compatibility risk — the BMS handshake is identical across all three.
• Bench tested on actual hardware: We ran this cell through charge and discharge cycles on IXUS-series bodies. The BMS accepted the cell without a rejection flag, held voltage above 3.5V through the working discharge window, and cut off cleanly at the low-voltage threshold before the camera triggered a forced shutdown.
• First charge on a new IXUS body: Some IXUS bodies calibrate the battery-remaining indicator during the first charge cycle performed inside the camera itself — not via an external charger. On first use, insert the cell and charge via the camera body using the supplied USB or AC adapter. This gives the BMS accurate reference points for the discharge curve on subsequent shoots.

Canon BMS rejecting a third-party NB-4L cell on first install

Canon compact cameras run a battery authentication check on power-up. A new third-party cell that hasn't completed a charge cycle inside the camera body can trigger a "Change the battery pack" warning even when the cell is fully charged externally. The BMS reads an unfamiliar charge signature and defaults to a reject state. To clear it, insert the cell, connect the camera to the OEM AC adapter or a USB power source, and run one full charge-to-completion cycle without interrupting it. After that cycle, the warning clears on most IXUS bodies.

Battery percentage jumping erratically on the IXUS display

The IXUS battery indicator maps voltage thresholds — not actual charge state — to the three-bar display. A replacement cell with a slightly different discharge curve can cause the indicator to drop from two bars to zero without warning, then recover after the camera rests. This isn't a faulty cell — it's a threshold mismatch. The cell is still holding charge correctly. Run two full charge and discharge cycles via the camera body and the indicator will stabilise as the BMS learns the new cell's voltage profile at each stage of discharge.