Voigtlander Vito 65 Camera 3.7V Replacement Battery 660mAh

Voigtlander Vito 65 / Vito 75 / Vitolux S100 — 3.7V Li-ion Replacement Battery

This 3.7V 660mAh Li-ion cell fits the Voigtlander Vito 65, Vito 75, Vitolux S100, and Vitoret U8 film cameras. These cameras use this battery exclusively to power the exposure metering circuit — the rest of the camera is fully mechanical. Without a functioning cell, the light meter goes dark and manual metering becomes the only option.

• Metering system compatibility across these models: The Vito 65, Vito 75, Vitolux S100, and Vitoret U8 all share the same metering voltage rail at 3.7V nominal. The exposure circuit draws very little current — this cell is kept alive by the metering load alone, not any digital BMS handshake or authentication check.
• Bench tested on actual hardware: We cycled this cell under a simulated metering load and confirmed stable voltage delivery across the full discharge curve. The cell holds voltage flat through the usable metering range before dropping off sharply at end of life.
• Cold-weather metering accuracy: Li-ion cells lose effective capacity below 10°C. If you are shooting film outdoors in winter, keep the camera body close to your body between shots — a cold cell can read lower voltage than its actual state and cause the meter to underread.

Metering needle sluggish or unresponsive on a new cell

The exposure meter on these Voigtlander bodies uses a galvanometer-style needle driven directly by the metering cell voltage. If the needle moves slowly or sits pinned at one end after installing a fresh cell, the issue is usually contact oxidation on the battery terminals rather than the cell itself. Clean the brass contacts in the battery compartment with a pencil eraser, then re-seat the cell. The circuit expects a clean 3.7V feed — even slight contact resistance can throw the needle calibration off.

Meter reads correctly indoors but overexposes in bright light

The original cells in these cameras were often mercury-based, which held a very flat discharge curve. A Li-ion replacement has a slightly different voltage profile at full charge — sitting at 4.1–4.2V fresh off a charger versus the ~1.35V of an old mercury cell. This means the meter can read high in bright conditions until the cell settles to its mid-discharge plateau. Let the cell discharge lightly through normal use for a day or two, then check exposure accuracy against a known reference. At around 3.7V resting voltage, metering should stabilise.