Month: July 2025

Direct answer: a swollen NP-FZ100 is done. Don’t use it, and don’t charge it. Swelling means gas has formed inside the cell and the internal structure is no longer stable. Further charging or discharging risks more expansion, leaking, or thermal runaway. The correct response is to stop using it, insulate the terminals, store it alone, and hand it over to a battery or hazardous waste collection point. The price of one pack is far below the cost of one incident, and this isn’t a place for optimism.

How to tell whether it’s swollen

Mild swelling isn’t always obvious to the eye. These checks will confirm it:

• The spin test. Set the pack on a flat table or a piece of glass and give it a gentle push. If it spins or rocks freely, the underside is no longer flat.
• Look at the seam. Is the case seam opened up, or do the sides bulge so the middle sits higher than the edges?
• How it fits. Noticeably tight going into the compartment, sticking on the way out, or a battery door that won’t close properly.
• How it feels. A hollow or slightly springy feel under light finger pressure, instead of the solid feel of a healthy pack.
• Companion symptoms. Sudden capacity loss, clear heat while charging, or the level jumping — all possible signs of internal trouble.

Any one of these is enough. Treat it as swollen and don’t wait for it to get more obvious.

Why packs swell

Cause	What happens	Preventable
Overcharging or failed charge control	Long overcharge, or a charger that doesn’t match the spec	Yes
Short circuit	Terminals touching metal, or an internal micro-short	Yes
High temperature	A car in summer sun, or long storage beside a radiator	Yes
Stored at full charge	Full charge plus heat accelerates gas formation	Yes
Deep over-discharge	Left unused without top-ups, cells take damage	Yes
Normal aging	Wear sets in after roughly 300–500 cycles	Only slowed
Physical damage	Drops, crushing, puncture	Yes

Almost every cause traces back to use and storage habits. Even a dropped pack that looks fine deserves an observation period before you trust it on paid work.

What to do once you find one

• Step 1: stop using it. No camera, no charging, and don’t try to drain it.
• Step 2: remove it. If it’s stuck in the compartment, don’t pry or force it — rock gently or use tape to pull, without squeezing the cell.
• Step 3: insulate the terminals. Tape over the contacts, or use the original packaging or a cap, so they can’t meet keys or coins.
• Step 4: store it alone. Dry, cool and away from anything flammable. Don’t stack it with other packs.
• Step 5: never puncture, crush or burn it. All of these can start a fire. Don’t put it in general trash either.
• Step 6: take it to a collection point. Hazardous waste facilities, electronics markets and retailer battery drop-offs, following local rules.
• Step 7: check the rest of the batch. Inspect other packs from the same set and the same charger, and retire them together if needed.

If a pack is smoking, clearly hot or smelling, move people and flammables away, keep the area ventilated and follow local emergency guidance.

Preventing the next one

• Use a charger that matches the spec on voltage and interface. Cheap chargers without protection circuitry carry more risk.
• Avoid sitting at full charge. If you’re not shooting for a few days, bring packs down to 40–60% rather than leaving them on the charger.
• Control temperature. Store around 15–25°C. No packs in a sunlit car, none beside a heater.
• Avoid over-discharge. Top up every three months in storage — see charging cycles and storage basics.
• Prevent shorts. Terminal covers or individual slots; no loose packs sharing space with metal objects.
• Don’t drop or crush them. Keep batteries in their own pouch, not under heavy gear at the bottom of a bag.
• Inspect routinely. A glance at each pack before and after a shoot catches problems early.

More on third-party pack safety in are aftermarket camera batteries safe; if the pack also shows recognition errors, the recognition troubleshooting steps applies.

FAQ

Can I keep using a slightly swollen pack for a while?

We wouldn’t. Swelling is irreversible and progresses unpredictably — especially not on a job that matters.

Can I fly with a swollen battery?

No. Lithium cells in an abnormal condition aren’t permitted on aircraft, in the cabin or in checked bags. Dispose of it through a collection point instead.

Can I release the gas and carry on?

No. Puncturing or squeezing to vent gas destroys the internal structure and can cause a short and a fire. It’s a dangerous maneuver — never try it.

How do I tell swelling apart from a normal curved case?

A healthy pack sits flat and doesn’t rock on a tabletop. The spin test answers it in a second; if it rocks, treat it as swollen.

Two charging options, same capacity: standard 2600mAh (dock required) or USB-C 2600mAh (phone charger or power bank). Pick the version on the NP-FZ100 product page; bulk pricing via wholesale.

When a body starts shutting down and a full pack lasts half as long as it used to, the usual cause is an aged battery, with body settings and environment coming second. Work in this order: rule out settings and environment first, run one full cycle to recalibrate the gauge, then swap in a known-good pack to see which side the problem sits on. If several packs all run short in the same body, look at the body. If only one pack runs short, that pack has aged.

Rule Out Three Non-Ageing Causes First

• Cold: capacity drops noticeably below freezing, and around -10°C you may get roughly half of what you would at room temperature. Fast drain in winter usually recovers once the pack warms up; the coping strategy is in winter runtime.
• Power-hungry settings: a bright screen for composing, burst shooting, 4K recording, constant autofocus and playback all raise draw, so the frame count falls accordingly. Drop the screen brightness and cut playback for a day and see whether the numbers come back.
• An inaccurate gauge: a jumping percentage makes it look like runtime collapsed. Do one full charge-and-discharge cycle before you judge anything; the method is in calibrating the charge display.

Six Signs of an Aged Pack

Symptom	Likelihood of ageing	What it means
Drops to one bar after a few dozen frames from full	High	Usable capacity is well below the rating
Jumps from two bars straight to shutdown	High	Discharge curve collapses at the end; resistance is up
Cuts out at power-on or during a burst	High	Voltage sags under load and trips protection
Runs clearly hotter than packs from the same batch	Medium-high	Rising resistance produces more heat
Charges suspiciously fast, then dies just as fast	High	It is accepting less energy in the first place
Swollen or deformed shell	Safety issue	Stop using it and handle it as a safety issue

Note how the first, third and fifth rows combine. A pack that charges fast, empties fast and runs hot is aged, and you can treat that as settled.

How to Locate the Problem With a Swap Test

• Swap the pack: fit a known-good battery into the same body. If runtime returns to normal, the original pack was the problem.
• Swap the body: put the suspect pack into another body of the same model. If it still runs short, it is the pack.
• Change the conditions: test indoors at room temperature with the power-hungry settings off, to remove cold and settings from the equation.
• Count frames: log the shot count for two packs across the same outing. A written comparison beats an impression.

You do not need to-the-frame precision. You only need to see whether one pack is clearly behind the other. Official CIPA figures usually sit in the 500–700 frame range, while real-world use commonly lands closer to 60–80% of the rating, and lower again for video and bursts.

How Much Life Is Left: The Ageing Curve

Lithium cells typically retain around 80% of their capacity after 300–500 cycles, so “shorter after a year” is expected rather than alarming, and by roughly the two-year mark replacement deserves serious thought. Charging two or three times a week puts most people at that point somewhere between a year and a half and two years; heavier users arrive sooner. The full curve is laid out in capacity loss and replacement timing.

Situations Where You Should Just Replace It

• Ahead of a wedding, commercial shoot or trip, when one pack is clearly underperforming.
• Shutdowns during bursts or recording that have already cost you frames.
• Obvious heat while charging, or any swelling in the shell.
• Two-plus years of service, or cycle count approaching 300–500.

Heavy users should keep at least two packs in rotation so no single pack becomes the single point of failure in a shoot.

Habits That Slow Ageing

• Top up opportunistically rather than running to zero. Frequent deep discharge is hard on cells.
• Store long-term at roughly 40–60% charge, cool and dry at about 15–25°C, with a top-up every three months.
• Avoid leaving packs at 100%, especially in a hot place.
• Number your packs and rotate them, so none sits idle long enough to self-discharge into trouble.
• Keep terminals clean and dry. Wipe them down after coastal or wet shoots.

FAQ

It shuts down, then powers back up showing charge. Is the pack dead?

Probably aged. Start-up and burst shooting draw high current; voltage sags under that load and trips protection, then recovers once the pack rests. That rebound is a classic ageing signature.

Can a new pack shut the camera down too?

Yes, under high load in burst or 4K, or in the cold. Warm it up and retest at lower load. If it still cuts out in normal conditions, contact the seller.

Will recalibration bring capacity back?

No. A full cycle improves the accuracy of the display, not the energy the cell holds. If the real frame count is still short afterwards, the cell has genuinely degraded.

Can the body itself cause shutdowns?

It can. Firmware glitches, a heavy lens focus motor, or heat protection in hot weather can all shut a body down. Use the swap test to separate the two.

Only need a spare? The NP-FZ100 2600mAh comes on its own, with a charger, or as a two-battery kit. Both versions hold 2600mAh; the USB-C one costs slightly more and saves you carrying a dock.

A new NP-FZ100 that refuses to go in is rarely a dead battery. In most cases it is one of three things: wrong model, wrong orientation, or a protective film still on the terminals. Start by confirming the body belongs to the FZ100 family. A7 III, A7R III/IV/V, A7 IV, A7S III, the A9 series, A1, A6600, A6700, the A7C series, FX3, FX30 and ZV-E1 all run on this pack. A6400, A6500, A6300, A7 II, A7R II and A7S II take the NP-FW50, which looks broadly similar but physically will not seat. Once the model is right, work through orientation, latch, then contacts. Most cases resolve in a minute or two. Do not press hard.

Step 1: Make Sure You Bought an NP-FZ100

This is the most common cause. Plenty of orders get placed under a generic “Sony mirrorless battery” listing and arrive as an FW50 or a BX1. The three families differ in size, capacity and latch position, and they cannot be swapped. The full cross-reference lives in Sony mirrorless battery comparison chart, and the body-by-body list is in every camera that takes the NP-FZ100.

• NP-FZ100: most full-frame and flagship bodies from the A7 III onward, rated around 2600mAh / 7.4V / 19.24Wh.
• NP-FW50: earlier bodies such as the A6000, A6300, A6400, A6500, A7, A7 II, A7R II and A7S II.
• NP-BX1: compact cameras like the RX100 series.

One more naming trap worth knowing: NP-FZ100 (USB-C) is the 2600mAh variant. Its shell and latch are identical, so it drops into the same bodies — the difference is the cell rating, not the fit.

Step 2: Check Orientation and Latch Position

The NP-FZ100 is directional. The front face usually carries an arrow or a body diagram; the terminal side goes inward, and the side with the latch notch lines up with the spring catch inside the compartment.

• Open the compartment door fully and look at which way the contacts inside face.
• Terminals inward, label outward. Push straight along the rails, not at an angle.
• You should hear a faint click at the end of travel — that is the catch engaging.
• If the tail of the pack sits proud, it is not seated. Take it out and start over rather than closing the door against it.

Reversed, the pack simply will not go in. That is the point to stop pushing: forcing it can bend the spring contact in the compartment or scratch the terminal plating.

Step 3: Check for Terminal Film and Packaging Residue

Some packs ship with a thin transparent film or plastic strip over the terminals for short-circuit protection. It is close in colour to the contacts and easy to miss. Hold the pack up to the light before loading and confirm the metal is fully exposed, with no film and no adhesive residue. Film in place means no power, and the body may report that it cannot read the battery.

Step 4: When the Latch Feels Too Tight

A fresh pack with tight shell and latch tolerances is normal, and it usually loosens up after a few cycles.

• To insert: push the pack all the way in, press with the flat of your finger near the tail by the latch, and release once you hear the click.
• To remove: flick the release lever inside the compartment first. The pack will lift slightly on its own, then pinch and pull it out. Do not dig into the side of the pack and yank.
• Door will not close: the pack is not seated. Take it out, reload it, and check the compartment for debris or a bent spring.
• If the catch is genuinely stiff, a trace of dry lubricant on the plastic edges away from the terminals can help. Work it in with a few insert-and-remove cycles. Keep it off the contacts.

Step 5: Inspect the Pack and the Compartment

Look over the shell for swelling, deformation or flashing on the moulding, and check whether the terminals sit straight. Then look inside the compartment for debris and for a spring contact that is bent or loose. A swollen pack must never be forced in — set it aside and handle it as a safety issue. A visibly deformed spring is a body-side fault and belongs in a service centre, not in a battery replacement.

Three Checks Once It Is In

• Power on and confirm the charge indicator appears normally instead of a “cannot be used” message.
• Fire off a few frames and check that playback is clean.
• Charge it fully before the first outing rather than heading out on shipping charge.

If a full pack drains quickly, or the gauge drops from two bars straight to shutdown, a full charge-and-discharge recalibration usually helps. The procedure is in fixing an inaccurate charge display.

FAQ

The pack goes in but will not latch and pops out when touched

Usually the catch has not engaged, or the compartment catch is worn. Make sure you push to the end and hear the click. If it keeps happening, check the latch notch on the pack for flashing and ask the seller for a replacement if needed.

It is in but the camera does nothing — is it reversed?

Reversed, it would not have gone in. No power at all is more likely film on the terminals, dirty contacts or a flat pack. Charge it, wipe the contacts with a dry cloth, and try again before assuming a fault.

I forced it once. Can that damage the camera?

One light squeeze is unlikely to cause damage, but check the compartment contacts for deformation and the pack shell for cracks. Watch for “not recognised” messages or odd shutdowns over the next few shoots.

I have two packs and one is smooth while the other is tight

Batch tolerances vary and that is normal. The tighter one usually improves with use. As long as it latches and delivers stable power, it is fine.

Only need a spare? The NP-FZ100 2600mAh comes on its own, with a charger, or as a two-battery kit. Both versions hold 2600mAh; the USB-C one costs slightly more and saves you carrying a dock.

The short answer: Canon’s LP-E6NH, Nikon’s EN-EL15 series, and Sony’s NP-FZ100 belong to the same class — roughly 15–17Wh of energy and 2100–2600mAh of capacity — and the differences between them are much smaller than the differences between the cameras they power. None of the three interchange. Shape, contacts, and communication protocols all differ; each pack serves only its own brand’s bodies. What decides how long you can shoot is your camera’s power draw and how you use it, not the handful of milliamp-hours between these three cells. Below is the spec table, what each line actually means, and practical advice if you run more than one system. Sony’s internal split between battery families is covered separately in every Sony mirrorless battery model explained.

Spec comparison

Item	Canon LP-E6NH	Nikon EN-EL15 series	Sony NP-FZ100
Rated capacity	Around 2130mAh class	Around 2100–2600mAh (varies by version)	2280mAh (original) / 2600mAh (our compatible version)
Nominal voltage	Around 7.4V	Around 7.0V	7.2V
Energy (Wh)	Around 15Wh class	Around 15–16Wh class	About 16.4Wh (original) / 18.72–19.24Wh (our compatible version)
Chemistry	Lithium-ion	Lithium-ion	Lithium-ion
Typical bodies	EOS R5, R6 series, 5D series, others	Z-series mirrorless, D850, D500, others	A7 III/IV, A7R III/IV/V, A7S III, A9 series, A1, A6600, A6700, A7C series, FX3, FX30, ZV-E1
In-camera fuel gauge	Supported	Supported	Supported
Interchangeability	None across the three; no adapter exists
Air travel	All far below 100Wh; spares go in carry-on, never checked

Note: the table summarizes published specifications at the order-of-magnitude level; variants and revisions shift individual figures slightly, so treat each maker’s official rating as authoritative. We make no pricing or purchasing recommendation for Canon or Nikon original batteries.

Reading the numbers

Wh is the only fair comparison

You can’t compare mAh across different voltages; energy can. Wh = capacity (Ah) × voltage (V). Run all three through that and they cluster within about ten percent of each other in the 15–17Wh band. Same shooting load, similar theoretical ceiling.

Runtime differences live in the camera

Runtime equals capacity divided by draw. A high-resolution stacked-sensor body, an 8K video body, or something with aggressive stabilization and live view can draw several times more than a simpler camera. Most “brand X lasts longer” conclusions are really comparisons between cameras.

What the voltage gap means

The EN-EL15 line sits at about 7.0V while the LP-E6NH and FZ100 run about 7.2V — the same design class either way. It reflects each company’s internal power design, not superiority in one direction or another.

Communication and the fuel gauge

All three report percentage remaining inside their own bodies. With third-party packs, some Sony cameras show a notice that remaining charge may display inaccurately; you can keep shooting, it’s expected behavior. A harsher “cannot be used” message warrants investigation — start with the contacts and the compatibility list.

Three hard reasons they don’t interchange

• Mechanical fit. Different length, width, depth, and latch design; each physically refuses the other’s bay.
• Contacts and protocol. Even where shapes look similar, pin definitions and handshakes differ, so the body can’t identify the pack.
• Voltage and discharge behavior. Forcing it risks short circuits, over-discharge, and damage. Not worth attempting.

Battery planning if you shoot multiple systems

Scenario	Suggested kit	Notes
Sony body, everyday shooting	Two NP-FZ100 packs	Covers a normal day comfortably
Sony body, weddings or commercial work	Three or four NP-FZ100 packs	Heavy bursts and video
Locked-off long recording	Two packs plus a dummy battery	Cuts downtime for swaps
Running Sony alongside Canon or Nikon	Separate pools per system	Never mix them in one pouch; label by system
Cold environments	1.5–2 times your usual count	At -10°C you may keep only about half

Three things that actually matter when buying

• The model matches your body. Confirm the battery type first, then compare capacity and price.
• The specs are stated plainly. Capacity, voltage, and energy should all be printed. Vague labeling deserves suspicion.
• Warranty and batch are documented. Clear return terms and a visible production or batch code; both should be visible on the pack or its packaging.

On price, Sony’s original NP-FZ100 generally starts at $70 and up through official channels. Compatible cells are a legitimate alternative: YO’s NP-FZ100 is around $17.89, about $22.93 with one battery and a charger, and about $36.74 for two batteries and a charger.

FAQ

Similar energy means any system is the same choice, right?

Batteries, close enough. Cameras, not remotely — power draw varies widely. Pick a system for its bodies and lenses; the battery only determines how many you carry.

Can an adapter or mod make them cross-compatible?

We don’t recommend trying. Voltage, discharge characteristics, and protocols all differ, and improvising risks short circuits and damaged gear.

Why doesn’t Sony push FZ100 capacity higher?

Physical size and weight set the limits, as do shipping and aviation safety rules. The current approach is raising energy density within the same footprint — hence USB-C versions.

Does care differ between the three?

Not meaningfully. Top up often, avoid sitting at 100%, store at 40%–60% in a cool dry place, recharge every three months, and retire anything that swells.

Bottom line and buying notes

Two charging options, same capacity: standard 2600mAh (dock required) or USB-C 2600mAh (phone charger or power bank). Pick the version on the NP-FZ100 product page; bulk pricing via wholesale.