Short answer: these three are not a new-for-old replacement chain but three parallel tiers matched to body class. The DMW-BLK22 (about 2200mAh / 16Wh) serves the S5 series, GH6, GH5 II and G9 II; the DMW-BLF19 (about 1860mAh / 13.4Wh) is for the GH5, GH5S, original G9 and GH4 generation; and the DMW-BLG10 (about 1025mAh / 7.4Wh) is for small bodies such as the GX85 and GX9. Their latches and contact positions all differ, so none will physically fit another’s slot. The only reliable basis for choosing is the model marking in the camera’s battery compartment — not the mount, and not the release date.
Many people discover their spares are useless only after changing bodies, and the habit of buying by mount is usually the cause. The boundaries between the three are set out below.
1. How the three tiers differ
In the M43 era Panasonic split batteries by body size: small bodies took a thin pack to stay portable, flagships took a thicker one to support cooling and video performance. That logic carried into the L-mount era, with new model names.
| Model | Nominal capacity | Energy | Typical fitment |
|---|---|---|---|
| DMW-BLK22 | About 2200mAh | About 16Wh | S5, S5 II, S5 II X, GH6, GH5 II, G9 II |
| DMW-BLF19 | About 1860mAh | About 13.4Wh | GH3, GH4, GH5, GH5S, G9 (original) |
| DMW-BLG10 | About 1025mAh | About 7.4Wh | GX85 / GX80, GX9, GF9 / GX850 and other small bodies |
On paper the BLK22 holds about 20% more energy than the BLF19 and more than twice the BLG10. But a capacity gap is not a runtime gap: the bodies that take the BLG10 are mostly entry-level or portable designs with restrained features, so 7.4Wh is not especially tight there, while the BLK22 faces high-draw bodies like the S5 II and GH6 where 16Wh counts as merely adequate.
2. Why “L mount means BLK22” is wrong
This is the most common misconception. L-mount bodies do not share one battery: the S1, S1R and S1H use the DMW-BLJ31, which is noticeably larger in both size and capacity than the BLK22, while only the S5 series uses the BLK22. In other words, incompatible battery specs exist within a single mount.
The reverse also happens: compatibility can cross mounts, since the BLK22 serves both the L-mount S5 series and the M43 GH6, GH5 II and G9 II. That shows the split is driven by body platform and power design, not by lens mount. Remove “mount” from your criteria when buying and most mistakes disappear.
3. A four-step method for choosing
If you are unsure which pack your camera needs, work through these in order; it usually takes a minute or two.
- Open the compartment and read the marking: the back of the pack or the inside of the door usually carries a DMW- model number, which is the most authoritative source.
- Match the full body designation: note that the GH5 and GH5 II, and the G9 and G9 II, are separate generations with different batteries. A “II” suffix often signals a battery change.
- Compare contact count and latch shape: the BLK22 and BLF19 are similar in thickness, but the latch notch sits in a different place and the contact layout differs, which is visible to the eye.
- Then confirm charging: newer bodies mostly support USB-C PD in-body charging while older ones rely on a dock, which affects how many packs and chargers you buy.
If you run both L-mount and M43 systems, favour a combination that shares batteries — an S5 II with a G9 II, for instance — so spares and chargers overlap and you carry one battery type instead of two. The real burden is much smaller than the spec sheets suggest.
4. Mixing, adapters and third-party packs
Adapters advertised as “BLF19 to BLK22” turn up occasionally, but most only change the shape and cannot bridge the protocol differences. When the body cannot read battery temperature and cycle data, the mild outcome is a wrong charge reading and the severe one is a refusal to power on or a sudden shutdown mid-recording — a serious risk to footage being written. They are not advisable for paid work.
Third-party selection is more straightforward: keep capacity claims reasonable, require a complete protection circuit and prefer products that name the supported bodies. Brands such as YO list both BLK22 and BLF19 equivalents at modest prices, suitable as a supplement rather than a replacement. Two things are worth watching: buy the same batch, so that mixing old and new packs still gives a linear charge reading; and keep a return channel open, since some batches show compatibility prompts on high-draw bodies such as the GH6.
For a cross-brand reference on capacity and cold behaviour, the test methods in the NP-FZ100 section apply to any brand; if you shoot outdoors in the cold year-round, the operational detail in our minus 10°C battery test is worth reading first. Buying and care advice specific to the BLK22 is collected on the DMW-BLK22 category page.
FAQ
Will a BLF19 fit a GH5 II?
No. The GH5 II moved to the DMW-BLK22, and both compartment dimensions and contact positions differ, so a BLF19 will not seat properly. Only the original GH5 and GH5S take the BLF19, and since the two generations look alike, check the full model designation.
How big is the capacity gap between the BLG10 and BLK22?
By nominal energy, the BLK22’s 16Wh is more than twice the BLG10’s 7.4Wh. But they serve different body classes, so the multiple does not translate into shot counts — small bodies draw less, so each watt-hour goes further.
Are batteries always shared within a mount?
No. The L mount alone spans the BLJ31 and BLK22 among others, and S1-series packs will not fit an S5. Judge by body platform and battery model, not by lens mount.
Can the chargers for the three be mixed?
No. Panasonic docks are shaped around a specific pack and contact layout, so BLK22 and BLF19 chargers are not interchangeable, and forcing a pack in can cause poor contact. If you run several bodies, match chargers to battery models, or favour bodies with USB-C in-body charging to cut down on accessories.