About this replacement
Panasonic Lumix DC-S5 / GH5 / G9 — 7.4V Li-ion Replacement Battery (DMW-BLK22)
This is a 7.4V, 2150mAh Li-ion cell built to the DMW-BLK22 spec. It fits the Lumix DC-S5, DC-S5K, GH5, and G9 — full-frame and Micro Four Thirds mirrorless bodies that share the same battery bay and BMS communication protocol. Swap it in when your original cell no longer holds a charge across a full shoot.
- Cross-body compatibility on the DMW-BLK22 platform: The S5, S5K, GH5, and G9 all draw from the same 7.4V rail and use the same physical connector and BMS handshake. Panasonic standardised this pack across both sensor formats, so one spare covers multiple bodies in a mixed kit.
- Bench tested on actual hardware: We ran this cell through charge and discharge cycles on a GH5 body. The BMS accepted the pack without fault codes, reported capacity within normal variance, and the protection circuit tripped correctly at low-voltage cutoff — no forced shutdowns mid-cycle.
- First-install charge cycle on Panasonic bodies: Charge the new cell to 100% inside the camera body or OEM charger before your first shoot. The S5 and GH5 BMS maps battery-remaining percentages against a charge-curve baseline — skipping this step causes the indicator to jump erratically until the camera has logged one full cycle.
Battery percentage jumping on the S5 display after fitting a new cell
The Lumix DC-S5 uses a voltage-curve map to calculate remaining charge. A new cell has a discharge curve that hasn't been profiled by the camera's BMS yet. Until the body logs a full charge-to-cutoff cycle, the percentage readout can skip — commonly dropping 20–30% at once between shots. Run one complete charge cycle from within the camera body or OEM charger, and the indicator stabilises. After that cycle, the display should track the cell's actual state of charge to within a few percent.
Lumix DC-S5 showing dead battery icon on a cell that was just charged
This is the S5's BMS authentication check firing on a cell it hasn't yet accepted. It does not mean the battery is faulty. Connect the pack to an OEM charger or insert it into the camera body and start a charge from zero — even if the cell reads full. The camera logs the cell during that charge handshake. Once the cycle completes and the body wakes cleanly, the dead battery icon clears and the camera operates normally. If the icon returns after a second full cycle, measure open-circuit voltage — a healthy DMW-BLK22 cell at rest should read between 7.2V and 8.4V.