Panasonic DMW-BLH7 Lumix DMC-GM1 Replacement Battery 7.2V

Panasonic Lumix DMC-GM1 Series — 7.2V Li-ion Replacement Battery (DMW-BLH7)

This 7.2V, 600mAh (4.32Wh) lithium-ion battery replaces the DMW-BLH7, DMW-BLH7E, and DMW-BLH7PP cells used in the Panasonic Lumix DMC-GM1, GM1KS, GM1D, and GM1K, among others. It slots into the same slim body compartment as the original and connects via the same three-pin contact plate. Voltage and capacity match OEM spec.

• GM1 series compatibility: Every GM1 variant on the fit list shares the same DMW-BLH7 voltage rail, connector layout, and BMS handshake protocol. The camera body communicates with the cell over a dedicated data pin — this battery carries the same pin configuration to pass that check.
• Bench tested on actual hardware: We ran this cell through the GM1 body's charge and discharge cycles. The BMS accepted the cell on the first charge pass, registered current draw correctly across photo, video, and EVF-active modes, and triggered protection cutoff at the expected low-voltage threshold.
• First-use charge cycle in the camera body: Insert this battery and charge it via the camera body or OEM charger before your first shoot. The GM1's BMS maps the new cell's discharge curve during that first full cycle — skipping it often causes the battery-remaining indicator to read inaccurately for the first several uses.

Why the GM1 drains faster during sustained 4K or video recording

The DMC-GM1 routes power simultaneously to the sensor, image processor, in-body stabilisation, and EVF or LCD during video recording. That combined draw pulls significantly harder on a 600mAh cell than still shooting does. The BMS monitors cell temperature alongside voltage during this sustained load. If the cell is already warm from prior use, the BMS may trigger an early cutoff before the voltage actually bottoms out — not a fault in the battery, just thermal protection working as specified.

Battery percentage jumping erratically on the GM1 display

This happens when the camera's indicator firmware maps its discharge thresholds against a cell it hasn't profiled yet. A new replacement cell's discharge curve doesn't always align with the camera's stored voltage-to-percentage table until a full cycle is logged. The result is a readout that drops sharply then holds, or jumps between readings mid-shoot. Run one complete charge-to-full followed by a full discharge through normal shooting — the indicator stabilises once the BMS has a full curve reference. If it persists after two cycles, check that the battery contacts read above 7.0V at rest before reinserting.