Pentax D-LI106 Optio X90 Replacement Battery 3.7V 1000mAh

Pentax Optio X90 / MX-1 — 3.7V Li-ion Replacement Battery (D-LI106)

This is a 3.7V, 1000mAh Li-ion cell built to the D-LI106 specification. It fits the Pentax Optio X90 and MX-1 compact cameras. The battery slots into the same compartment as the original and draws power through the same contact layout.

• Optio X90 and MX-1 compatibility: Both cameras run off the same D-LI106 footprint — shared voltage rail at 3.7V, identical connector orientation, and the same BMS handshake protocol. One cell covers both bodies without modification.
• Bench tested on actual hardware: We cycled this cell through the Optio X90 body and tracked BMS behaviour across charge and discharge. The protection circuit tripped correctly at low-voltage cutoff and accepted full recharge without fault codes.
• First-install charge cycle: Insert this cell into the camera body or OEM charger and run one complete charge before heavy shooting. Some Pentax BMS builds only begin accurate battery-remaining display after a full charge cycle is completed inside the camera body itself.

Battery percentage jumping on the Optio X90 display after fitting a new cell

The Optio X90 maps its battery indicator to a fixed voltage-threshold table calibrated against the original cell's discharge curve. A new replacement cell — even at the correct capacity — may discharge along a slightly different voltage slope. The camera reads those voltage points and maps them to the wrong percentage segments, producing visible jumps. Running one full charge-discharge cycle inside the camera body allows the BMS to resample the curve and stabilise the indicator. After that cycle, the display should track consistently down to the low-battery cutoff near 3.0V.

Flash not fully recycling between shots on a new D-LI106 cell

The built-in flash on the Optio X90 pulls a short high-current spike to recharge its capacitor between frames. If the cell's internal resistance is slightly elevated — common in a new cell that hasn't been cycled yet — that current draw causes a momentary voltage sag the BMS interprets as marginal charge. The camera then throttles flash recharge to protect the circuit, extending recycle time. Cycle the battery fully once and retest; internal resistance drops after the first complete cycle and recycle time returns to normal.