Short answer: a TNP-FZ100 takes roughly 5–7 hours on an old 5V/1A charger, 3.5–5 hours on a 5V/2A phone charger, 4–6 hours from a power bank, and 2.5–3.5 hours on an 18W-or-better PD charger. These are ranges rather than fixed figures, because the same pack’s charging time shifts noticeably with input power, cable quality, starting charge and ambient temperature. Below we go through the three supply types, and note when you should expect to fall outside those ranges.
First, the variables: why one pack can differ by a factor of two
The NP-FZ100’s rated energy is 16.4Wh (2280mAh / 7.2V). In theory a 10W input would fill it in two hours, but charging is not a constant-power process: constant current first, constant voltage later, and the final 20% often takes a third of the total time. How much current the charger can supply and how much the battery management chip will accept — the lower of the two is what sets the speed.
Three factors are commonly overlooked. The cable: losses in a poor USB-C cable drop the voltage that actually reaches the pack, and the charging chip reduces current in response. Temperature: below 10°C or above 40°C, most battery management schemes deliberately cut current to protect the cells. And charging while in use: if the pack is simultaneously powering the camera, the charging current is shared, and the time stretches accordingly.
Realistic time ranges for the three supply types
The table assumes charging from near empty to full, an ambient temperature of 20–25°C, and the supplied or a competent cable. The figures reflect the normal behaviour of USB-C direct-charge packs; individual units vary by tens of minutes.
| Supply type | Typical output | Time to full | Good for |
|---|---|---|---|
| Old phone charger | 5V/1A | About 5–7 hours | Plug in overnight, take it in the morning |
| Standard phone fast charger | 5V/2A | About 3.5–5 hours | Office or hotel room overnight |
| Power bank | 5V/2.1A | About 4–6 hours | On location, in transit |
| PD charger | 18W and above | About 2.5–3.5 hours | Fast top-up after a shoot, rotating several packs |
| Laptop USB-C port | Around 5V/1.5A | About 4–6 hours | Charging while you work, without using a socket |
Phone chargers: the tier people underestimate
Many of us still have a five-year-old 5V/1A charger in a drawer. It will charge the pack, but it will eat most of a day. If you need the battery first thing in the morning, plugging in overnight is fine; if you discover an empty pack at three in the afternoon and you are shooting at seven, this tier will not save you.
5V/2A is the value sweet spot
The 5V/2A charger bundled with most phones already brings the time down to around four hours, and the gap to a PD charger is far smaller than the price gap. For anyone with one or two packs and an unhurried schedule, this tier is enough, and there is no need to buy extra gear for fast charging.
Multi-port chargers share the power
Charge two packs and a phone at once from a three-way station and the total output is divided, each pack gets less current, and the times stretch proportionally. If you want speed, plug in separately; if you want to save sockets, accept slower charging. You cannot have both.
Power banks: portable, but count the conversion losses
A power bank is rated at 3.7V cell capacity. Getting that to 5V and then into the battery involves a boost conversion, and usable energy is typically only sixty to seventy percent of the nominal figure. From a 10,000mAh bank, two to three full charges of a 16.4Wh pack is a realistic expectation; do not divide the numbers and assume four.
Cold weather makes this worse. Below freezing the bank’s own output falls and the pack restricts charging current, so both sides are discounted at once and a four-hour charge can become six or more. Our notes on battery behaviour at low temperature have the detail, and are worth reading before a winter shoot.
PD chargers: fastest, but do not expect the full rating
The advantage of PD is that after negotiation it can supply a higher voltage, which reduces line losses and lets more power through. But a charger rated at 65W does not mean the battery will draw 65W — the charging chip on the battery side has a ceiling, and anything above it simply goes unused. In practice the gap between a 65W and a 30W charger on this pack is smaller than the numbers suggest.
The most practical way to find out how fast your combination really runs is to watch the indicator rhythm on the pack or the charging prompt on the camera, then time one charge from empty to full. One measurement beats any datasheet.
Planning top-ups when you rotate several packs
- Back at the hotel, put the empty pack on the PD charger first — do not wait until after your shower to remember.
- Charge the second on the 5V/2A charger at the same time, avoiding a multi-port split that would slow both.
- Leave the third for tomorrow and take it to about 80%; storing at full charge long term is unkind to cycle life.
- Check the power bank’s level before you leave, and in cold weather carry packs in an inside pocket rather than the outer pocket of the camera bag.
- On multi-day shoots, a dual-slot charging case handles two packs overnight in one go.
The point of this routine is not the shortest possible time but making “there is always one pack at full charge” a habit. No charging speed rescues the evening you forgot. For more on matching bodies and batteries, see the TNP-FZ100 section.
FAQ
Why is my TNP-FZ100 still not full after six hours?
Look at the charger first. An old 5V/1A unit takes five to seven hours by nature, which is normal. If you are already on a 2A-or-better supply and it is still slow, check whether the cable supports higher current, whether the plug is fully seated, and whether the ambient temperature is unusually low or high.
Can I use a phone fast charger without damaging the battery?
Yes. USB-C charging negotiates voltage and current first, and the pack only accepts the tiers it can handle, so a powerful charger cannot force current into it. The precondition is that the charger and cable are legitimate products; poor accessories are the real risk.
Does unplugging halfway through harm the battery?
No. Lithium cells have no memory effect, and partial charging is normal use. If anything, routinely running the pack to auto-shutdown before recharging is worse for cycle life.
Does charging while shooting make it slower?
Yes. The pack keeps discharging while the camera records, the charging current is shared, and the time stretches noticeably, with both the body and the pack getting warmer. For long takes it is better to keep a charged pack in rotation than to push on with a cable; the limits are set out in our FZ100 battery section.