About this replacement
Panasonic Lumix DC-S5 / GH5 / G9 — 7.4V Li-ion Replacement Battery (DMW-BLK22)
This is a 7.4V, 1600mAh Li-ion replacement for the Panasonic DMW-BLK22 battery. It fits the Lumix DC-S5, DC-S5K, GH5, and G9 mirrorless cameras. Dimensions match the OEM cell at 56.85 × 39.35 × 21.00mm, so it seats and latches correctly in the battery compartment.
- DC-S5, GH5, and G9 compatibility: These models share the DMW-BLK22 form factor and 7.4V supply rail. The battery compartment connector and BMS communication protocol are consistent across the range, so one cell works across all listed bodies.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on the DC-S5 body. The BMS handshake completed on first install, and the camera accepted the cell without error flags during both stills and 4K video recording.
- First-cycle conditioning on the S5: Insert the cell and run a full charge via the camera body or OEM charger before your first shoot. The DC-S5 BMS maps its battery-remaining display against the discharge curve it reads during that initial charge cycle — skipping it can cause the indicator to read inaccurately from the start.
Why the DC-S5 drains faster during sustained 4K recording
The DC-S5 pulls from the battery on multiple fronts simultaneously during video: full-frame sensor readout, image processing, in-body stabilisation, and active cooling all run at once. This combined draw is significantly higher than stills shooting and will reduce shot count compared to single-frame bursts. The IBIS system alone adds consistent current draw that spec shot counts — which are measured under CIPA stills conditions — do not reflect. For long video sessions, carry a second cell rather than expecting stills-based estimates to hold.
Battery percentage jumping erratically on the DC-S5 display
This happens when the camera's fuel gauge hasn't calibrated its indicator thresholds to the new cell's discharge curve. The BMS tracks voltage drop across the discharge cycle, and a replacement cell can present a slightly different curve than the OEM unit, causing the percentage readout to skip or stall at certain levels. Run two or three full charge-to-discharge cycles and the indicator will track more accurately. If it persists past three cycles, charge the cell fully to 8.4V via the OEM charger, then discharge it normally through the camera body before checking again.