Samsung SLB-07A Replacement Battery 3.7V 720mAh Li-ion

Samsung ST50 / ST500 / ST550 / TL100 — 3.7V Li-ion Replacement Battery (SLB-07A)

The SLB-07A is a 3.7V, 720mAh Li-ion cell that fits a range of Samsung compact cameras including the ST50, ST500, ST550, and TL100. It slots into the same battery compartment as the original and draws from the same voltage rail. Capacity figure is taken directly from product specifications — 2.66Wh total energy.

• ST50 / ST500 / ST550 / TL100 compatibility: These models share the same 3.7V battery bay, connector pinout, and BMS communication protocol — one cell works across all of them without modification.
• Bench tested on actual hardware: We cycled this cell through a full charge and discharge on the ST50 body. The BMS accepted the cell, reported charge state correctly, and held voltage above 3.5V through the bulk of the discharge curve.
• First-charge protocol on the ST50: Run the initial charge inside the camera body rather than a third-party external charger — the ST50's BMS performs a handshake during in-body charging that calibrates the battery-remaining indicator for accurate shot count display.

Battery percentage jumping erratically on the ST50 display

Samsung's compact camera firmware maps battery percentage against the original cell's discharge curve. A fresh replacement cell — even with identical voltage — can sit slightly outside that curve, especially in the mid-range between 3.6V and 3.8V. The indicator reads the voltage directly and converts it, so any deviation from the expected curve shows up as a jump or sudden drop. Running two full charge-discharge cycles in the camera body allows the BMS to refine its threshold mapping and stabilise the display.

Camera showing a dead battery icon immediately after inserting a charged SLB-07A

This happens when the cell voltage has dipped below the ST50's minimum recognition threshold — typically around 3.2V — during storage or shipping. The camera reads the voltage on insertion and refuses to boot if it falls below that floor. Place the cell in an OEM-compatible charger until the indicator shows at least a partial charge, then reinsert. At 3.4V or above, the camera body will accept the cell and begin normal operation.