Short answer: on these DSLRs the body does not charge the battery at all, so a dock charger is the whole story.The original MH-24 dock is the least fuss, while a third-party USB dock is cheaper and more universal. Divide the 8.07Wh in the pack by the power that actually reaches it and a 5W-class supply needs about two hours, a 10W-class supply a little over one, with the tail of the charge and cable losses accounting for the rest.
First, check whether your body charges at all
This is where most people go wrong. On the D3100 through D3500 and the D5100 through D5600, the USB port is for data transfer. It cannot charge the battery inside the camera. The box contains an MH-24 dock, and charging means taking the pack out.
The Df follows the same pattern. The Coolpix P7000, P7100, P7700 and P7800 are compact cameras, and some of them do accept USB charging of the internal pack. Check the manual for your specific model rather than assuming the whole family behaves alike.
In other words, for almost every EN-EL14 owner, how do I charge this is really which dock should I use.
Four methods, estimated times
The arithmetic is simple. Take the pack’s 8.07Wh typical rating (7.70Wh nominal) and divide by the power reaching the cell. A charger labelled 5W or 10W is quoting input power, and conversion plus cable losses eat part of it, so the figures below assume about 80 percent efficiency. They are estimates, not manufacturer ratings.
| Method | Rough time (estimate) | Who it suits |
|---|---|---|
| In-body USB charging | Only some Coolpix models; about 2 hours at a 5V/1A level | Travelling with the body only and topping up briefly |
| Original MH-24 dock | About 1 hour at roughly 8W input; realistically 1.5 to 2 hours with the tapering tail | Charging at home or in a hotel, rotating two packs |
| Third-party USB dock (5V/1A) | 8.07 ÷ (5×0.8) ≈ 2 hours | Budget setups and travel spares |
| Third-party USB dock (5V/2A) | 8.07 ÷ (10×0.8) ≈ 1 hour | Faster turnaround when a multi-port charger is already on hand |
| Power bank plus USB dock | Depends on the bank: about 2 hours at 5V/1A, about 1 hour at 5V/2A | Outdoor shoots, travel, venues without mains power |
The numbers are for scale, not stopwatch accuracy. Three things stretch them: current tapering at the end of the cycle, losses in the cable and connector, and a protection board that limits current when the pack is cold.
Choosing between them
At a fixed base, the original dock is the least effort. Put the pack in and walk away. Its contact layout and detection logic match the pack, so compatibility is not a question.
For frequent travel, a 5V/2A third-party USB dock plus a multi-port charger weighs less than the original dock and charges a phone at the same time. Check that the metal pins line up with the EN-EL14 terminals before buying. A misaligned or reversed insertion shows up as a blinking light and no charge.
Outdoors and on long trips, a power bank with a USB dock is the only practical option. The conversion is easy. A 10000mAh bank is roughly 37Wh, so four full charges are theoretically possible, and planning on three is sensible once losses are counted.
What to avoid: unbranded chargers, charging in a car parked in the sun, and leaving a pack on the charger every night. These are general cautions rather than problems unique to this pack, but swollen cells usually trace back to this kind of use.
Small habits that extend pack life
- For the first two or three cycles, charge until the indicator goes out. No need to drain it flat first.
- For long storage, keep roughly half a charge and top it up every three months.
- Charge near room temperature. In winter, let a cold pack sit for a while before putting it on the dock.
- Rotate two packs rather than running one through constant cycles.
If you do not yet have a second pack, the EN-EL14+ compatible battery is rated 1090mAh at 7.4V and 8.07Wh, a little below the roughly 1230mAh of the original EN-EL14a, so plan spare capacity with that gap in mind. The body list is in the Nikon EN-EL14 series category.
FAQ
Can I charge an EN-EL14 with a phone charger?
Yes, as long as a USB dock sits in between. The phone charger only supplies power. Whether charging happens depends on the dock’s pin positions and detection circuit. A 5V/2A charger is faster than 5V/1A, but not twice as fast, because the battery-side management is the bottleneck.
Will an original MH-24 charge a third-party EN-EL14+?
Normally yes. The MH-24 judges charge state from voltage and temperature rather than a complex handshake. If the shell shape and contacts match, it will charge, though the indicator may behave slightly differently from an original pack.
Is a warm battery normal during charging?
Warm is normal, hot is not. Heat concentrated in the middle of the pack that feels merely warm is within normal range. If the shell becomes hot to the touch or starts to deform, stop using it immediately.
Can I leave it charging overnight?
A dock usually drops to a trickle or stops when the pack is full, so an occasional night is not a problem. Doing it every night brings no benefit. Charging during the day and unplugging when done is the safer habit.