What do I need to power my whole rig from one battery?

Three parts: a V-mount cell of 99 Wh or less, a plate that mounts it and provides D-Tap outputs, and a dummy battery that goes in the camera and takes power from D-Tap. That is about $256 together. Missing any one of them leaves either the camera or the accessories on their own cells, which is most of the problem you were trying to solve.

How do I calculate battery runtime?

Divide the watt hours by the total load in watts, then multiply by about 0.85 for conversion losses. A 99 Wh cell driving a camera at 8 W and a monitor at 6 W gives 99 divided by 14, times 0.85, which is around six hours. Add every continuously powered device, including transmitters, which draw whether or not you are recording.

Why are so many camera batteries exactly 99 Wh?

Because airlines allow lithium batteries under 100 Wh in carry-on with no approval and usually no quantity limit for personal equipment. Between 100 and 160 Wh needs approval and is typically limited to two, and above 160 Wh cannot fly. Manufacturers sit deliberately just under the threshold, which is why buying several 99 Wh cells beats buying one large one if you travel.

Can I run a video light from a V-mount battery?

Briefly. A 200 W fixture at full output drains a 99 Wh cell in under half an hour, which surprises almost everyone. The same fixture at 25 percent draws around 50 W and runs about three and a half hours on a 212 Wh cell. Location lighting is a mains job unless you plan for it with large cells and reduced output.

How should I store camera batteries?

At 50 to 60 percent charge, somewhere cool. Lithium cells degrade fastest when stored full and warm, so a battery left at 100 percent for six months loses noticeably more capacity than one stored half charged. Charge to full the night before a shoot rather than keeping everything permanently topped up, and run cells down before they go into long storage.

Is V-mount worth it on a small rig?

Not always. On a very light build going onto a 2 kg gimbal, a cell and plate add roughly 800 g at the back, which is a payload problem rather than a convenience. With only two powered devices, separate batteries are simpler and have no single point of failure. The threshold is about three powered devices, where cable and charger count tips the balance.

Camera Rig Power Guide: One Battery for the Whole Rig

Short answer

A single-battery rig needs three parts: a V-mount cell of 99 Wh or less so it can fly, a plate that mounts it and provides D-Tap outputs, and a dummy battery that feeds the camera from D-Tap. That is roughly $256 together, and it replaces three battery types and three chargers with one runtime number to watch.

An unplanned rig has three battery types, three chargers and three ways for the day to end early. A planned rig has one. The SmallRig VB99 Mini V-Mount, 99Wh plus a ZGCINE V-Mount Plate with Three D-Taps and USB-C plus a SmallRig NP-FZ100 D-Tap Dummy Battery is that system, and it removes the two most common shoot-enders at once while giving you a single number to plan around.

What a power system replaces

Camera batteries run the camera. NP-F cells run the monitor. AA cells run a microphone or a receiver. Each has its own charger, its own indicator, its own spares to keep track of, and its own way of running out at a moment you did not predict. That is the default state of a rig that grew rather than being designed.

A V-mount system replaces all of it with one cell that outputs through D-Tap and USB-C, feeding the camera through a dummy battery and everything else through cables. There is one charge state to check, one charger to remember, and one runtime figure to plan the day around.

It also gives you a number you can predict. A 99 Wh cell driving a 14 W load runs for roughly six hours after conversion losses, which is a plan. A camera battery indicator showing three bars is not a plan.

The three parts, and why all three are required

The cell. A SmallRig VB99 Mini V-Mount, 99Wh at around $160 is 99 Wh, which is the largest capacity airlines allow in carry-on without approval. Buy two rather than one larger one if you fly, because two 99 Wh cells are legal and one 200 Wh cell is not.

The plate. A SmallRig Foldable V-Mount Battery Plate at around $64 folds flat and mounts to a cage or rods. A ZGCINE V-Mount Plate with Three D-Taps and USB-C at $66 is an Arca plate with three D-Taps and USB-C, which is the better choice as soon as there are three things to power. The plate is what converts a battery into a mounting point and a set of outputs.

The dummy battery. A SmallRig NP-FZ100 D-Tap Dummy Battery at around $32 is a fake battery that goes into the camera and carries a D-Tap cable out through the battery door. Without it the camera is still on its own cells, which defeats the whole point. A Kondor Blue D-Tap to NP-FZ100 Cable is the same idea in a more robust cable, and cable robustness matters here because this cable moves constantly.

The complete first power system

Around $258 together. Every part is required; a missing one leaves the camera or the accessories on their own batteries.

Best value $159.99

SMALLRIG

SmallRig VB99 Mini V-Mount, 99Wh

99 Wh sits right under the usual 100 Wh airline ceiling, and PD 100 W out means it charges a laptop between setups too.

Capacity: 99 Wh
USB-C: PD 100 W

The default V-mount for a documentary kit.

Check price

EACHSHOT

ZGCINE V-Mount Plate with Three D-Taps and USB-C

Three D-Taps and a USB-C output on an Arca plate, which is enough to power a camera, a monitor and a transmitter from one battery.

Outputs: 3x D-Tap, USB-C

Check price

Camera power $31.98

SMALLRIG

SmallRig NP-FZ100 D-Tap Dummy Battery

The cable that turns a V-mount into camera power for Sony bodies, which is the whole reason to carry a V-mount at all.

For: Sony NP-FZ100 bodies

Match this to your camera's battery shape.

Check price

Working out runtime

Device	Typical draw	Notes
Mirrorless camera	6 to 9 W	Higher while recording, higher again in 4K 60
Cinema camera	15 to 25 W	Active cooling runs continuously
5 inch monitor, 1000 nits	5 to 7 W	Roughly doubles at full brightness
7 inch monitor, 2000 nits	10 to 14 W	The brightest panels are the biggest draw
External recorder	10 to 20 W	Higher when writing to a drive
Wireless video transmitter	6 to 10 W	Continuous, not only while recording
Wireless focus motor	3 to 6 W	Spikes on each pull
Field recorder	2 to 4 W	Often has its own cells anyway
COB light, 200 W class	50 to 200 W	A different order of magnitude entirely

The arithmetic is watt hours divided by watts, times roughly 0.85 for conversion losses. A 99 Wh cell driving a camera at 8 W and a monitor at 6 W is 99 divided by 14, times 0.85, which is about six hours. That is the calculation the battery runtime calculator runs, and doing it once before a shoot is worth more than any amount of carrying spares.

The 100 watt hour rule

Airlines classify lithium batteries by watt hours. Under 100 Wh they travel in carry-on with no approval and usually no quantity limit for personal equipment. Between 100 and 160 Wh they need airline approval and are typically limited to two. Above 160 Wh they cannot fly at all. In every case they are banned from checked baggage.

This is why so many camera batteries are rated at 98 or 99 Wh. Manufacturers are sitting deliberately just under the line. If your kit travels, buy multiple 99 Wh cells rather than fewer large ones, and keep the printed rating visible on the cell so it can be shown at a checkpoint.

If you never fly, larger cells are better value per watt hour and are the only sensible way to run lighting from a battery. The SmallRig VB212 V-Mount, 212Wh at 212 Wh will run a 50 W light for about three and a half hours, which a 99 Wh cell will not.

Cable discipline

Route every cable so it has slack at both ends and never becomes taut at any point in the rig's range of movement.
Clamp the video cable at the cage. This is what the HDMI clamp on a good cage exists for, and it transfers a snag from a soldered port to the frame.
Keep power cables away from audio cables where possible, since a power cable running alongside an unbalanced audio line can induce noise.
Use the shortest cable that reaches. Coiled excess is a snag point and it is where cables fail first.
Carry a spare of every cable in the rig. Cables are the single most frequent failure in any camera build.
Label both ends of anything that is not obvious, because tracing a cable in the dark is not a good use of a shoot.

The clamp point deserves repeating. On a mirrorless body the HDMI port is a micro connector soldered to a board, and a monitor cable is stiff. Without a clamp, every snag transfers directly into that solder joint, and the repair is a bench job.

Charging and battery care

A SmallRig Dual-Channel V-Mount Charger at around $110 charges two cells at once. That matters more than it sounds: with a single-bay charger a two-cell kit takes a whole evening to turn around, which is how people end up starting a shoot at 70 percent.

Store cells at 50 to 60 percent charge, somewhere cool. Lithium degrades fastest when held at full charge, especially warm, so a battery left at 100 percent on a shelf for six months loses noticeably more capacity than one left half charged. Charge to full the night before a shoot rather than keeping everything topped up permanently.

Expect real capacity loss in cold. Below about 5 degrees Celsius, capacity drops sharply and a cell that reads full in a warm vehicle will not deliver its rating outside. Keep spares inside a jacket rather than in a case, and plan for it rather than treating it as a fault.

When NP-F is still the right answer

On a very light rig where the whole point is minimal mass, a V-mount cell and plate add roughly 800 g at the back. If the rig is going on a 2 kg gimbal, that is a payload problem rather than a convenience, and a NEEWER NP-F970 Two-Battery Kit with Charger at around $48 running the monitor separately is genuinely the better answer.

On a rig with exactly two devices, the complexity of a distribution system is not repaid. A camera on its own batteries and a monitor on NP-F is simple, has no cables between the two, and has no single point of failure.

The threshold is roughly three powered devices. At three, the cable count and charger count of separate systems exceeds the cost of a single system, and the runtime prediction becomes genuinely useful rather than incidental.

Next, from here

Battery runtime calculator
Your actual load, against a real capacity.
Best V-mount batteries
The cells, compared.
V-mount versus NP-F
When the smaller format still wins.
Runtime chart by load
Every common load against every capacity.
How to build a camera rig
Where power sits in the build order.
Run and gun working build
The tier where single-battery power arrives.

Common questions

What do I need to power my whole rig from one battery?: Three parts: a V-mount cell of 99 Wh or less, a plate that mounts it and provides D-Tap outputs, and a dummy battery that goes in the camera and takes power from D-Tap. That is about $256 together. Missing any one of them leaves either the camera or the accessories on their own cells, which is most of the problem you were trying to solve.
How do I calculate battery runtime?: Divide the watt hours by the total load in watts, then multiply by about 0.85 for conversion losses. A 99 Wh cell driving a camera at 8 W and a monitor at 6 W gives 99 divided by 14, times 0.85, which is around six hours. Add every continuously powered device, including transmitters, which draw whether or not you are recording.
Why are so many camera batteries exactly 99 Wh?: Because airlines allow lithium batteries under 100 Wh in carry-on with no approval and usually no quantity limit for personal equipment. Between 100 and 160 Wh needs approval and is typically limited to two, and above 160 Wh cannot fly. Manufacturers sit deliberately just under the threshold, which is why buying several 99 Wh cells beats buying one large one if you travel.
Can I run a video light from a V-mount battery?: Briefly. A 200 W fixture at full output drains a 99 Wh cell in under half an hour, which surprises almost everyone. The same fixture at 25 percent draws around 50 W and runs about three and a half hours on a 212 Wh cell. Location lighting is a mains job unless you plan for it with large cells and reduced output.
How should I store camera batteries?: At 50 to 60 percent charge, somewhere cool. Lithium cells degrade fastest when stored full and warm, so a battery left at 100 percent for six months loses noticeably more capacity than one stored half charged. Charge to full the night before a shoot rather than keeping everything permanently topped up, and run cells down before they go into long storage.
Is V-mount worth it on a small rig?: Not always. On a very light build going onto a 2 kg gimbal, a cell and plate add roughly 800 g at the back, which is a payload problem rather than a convenience. With only two powered devices, separate batteries are simpler and have no single point of failure. The threshold is about three powered devices, where cable and charger count tips the balance.

Totalling your own rig weight against your gimbal payload? The Camera Rig Build Planner is the paid version of these pages: 8 printable worksheets you fill in with your own numbers, plus the full PDF, $29.